South Asian river dolphin: Difference between revisions

South Asian river dolphin; Temporal range: 0.012–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓ Quaternary – recent
	Ganges river dolphin breaking the surface
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Infraorder:	Cetacea
Family:	Platanistidae
Genus:	Platanista; Wagler, 1830
Type species
	Delphinus gangeticus; Lebeck, 1801
Species
	Platanista gangetica; Platanista minor
	Current ranges of the Indus river dolphin and Ganges river dolphin

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South Asian river dolphins are toothed whales in the genus Platanista, which inhabit the waterways of the Indian subcontinent. They were historically considered to be one species (P. gangetica) with the Ganges river dolphin and the Indus river dolphin being subspecies (P. g. gangetica and P. g. minor respectively). Genetic and morphological evidence led to their being described as separate species in 2021. The Ganges and Indus river dolphins are estimated to have diverged 550,000 years ago. They are the only living members of the family Platanistidae and the superfamily Platanistoidea. Fossils of ancient relatives date to the late Oligocene.

South Asian river dolphins are small but stocky cetaceans with long snouts or rostra, broad flippers, and small dorsal fins. They have several unusual features. Living in murky river waters, they have eyes that are tiny and lensless; the dolphins rely instead on echolocation for navigation. The skull has large crests over the melon, which help direct their echolocation signals. These dolphins prey mainly on fish and shrimp and hunt them throughout the water column. They are active through the day and are sighted in small groups. Both species are listed as endangered by the IUCN Red List of mammals. Major threats include dams, barrages, fishing nets, and both chemical and acoustic pollution.

Taxonomy

South Asian river dolphins were traditionally considered to be one species, Platanista gangetica, with the Ganges and Indus River populations being subspecies (P. g. gangetica and P. g. minor, respectively). Heinrich Julius Lebeck named the Ganges river dolphin Delphinus gangeticus in 1801, while Johann Georg Wagler coined the genus name Platanista in 1830,^[3] a Latin word derived from the Greek "platanistēs", which may be related to the Greek words platē ("oar") or platē ("flat, broad").^[4] This name was first given to the Ganges dolphin by Pliny the Elder in Naturalis Historia back in 77 CE. In 1853, Richard Owen described a specimen from the Indus and considered it to be the same species as the Ganges river dolphin, but a smaller form.^[3]

Based on differences in skull and vertebrae structure, blood proteins, and lipids, scientists declared them to be separate species in the 1970s.^[5]^[6] The results of these studies were criticized for their small sample sizes and the absence of statistical analyses; by the late 1990s, the two populations were again considered to be two subspecies of a single species.^[7]^[6] A 2014 mitochondrial DNA study found insufficient differences to support their classification as separate species.^[6] However, a 2021 study reanalyzed the two populations and found significant genetic divergence and major differences in skull structure; this led to the conclusion that the two were indeed distinct species.^[3]

Evolution

South Asian river dolphins are the only surviving members of the family Platanistidae and the superfamily Platanistoidea.^[8] They are not closely related to other river dolphins of the families Lipotidae, Pontoporiidae, and Iniidae, which all independently adapted to freshwater habitats.^[9] The following cladogram is based on Gatesy and colleagues (2012) and McGowen and colleagues (2020); and shows the relationship of South Asian river dolphins to other living toothed whale families:^[10]^[11]

Toothed whales

	Sperm whales (Physeteridae)

	Dwarf sperm whales (Kogiidae)

South Asian river dolphins (Platanistidae)

Beaked whales (Ziphiidae)

South American river dolphins

	Pontoporiidae

	Iniidae

Delphinoidea

Oceanic dolphins (Delphinidae)

	Porpoises (Phocoenidae)

	Belugas, narwhals (Monodontidae)

Several fossil species have been classified under Platanistoidea, the earliest of which date back to the late Oligocene (c. 25 million years ago). The number of species peaked around the early Miocene (c. 19 million years ago) and declined afterward. Examples of ancient platanistids include the genera Otekaikea and Waipatia and the species Awamokoa tokarahi of late Oligocene New Zealand, the family Allodelphinidae of early Miocene North Pacific, and Notocetus vanbenedeni and Aondelphis talen of early Miocene Patagonia. Platanistidae fossils have been found in Miocene deposits in Europe and North America. Fossil Platanistoidea showed a diversity of cochlea shapes, though Platanista was unusual in that it developed flatter spirals with larger gaps between them.^[8]

During the middle Miocene, the ancestor of Platanista entered the Indo-Gangetic Plain, then covered by inland seas, and remained there when sea levels dropped in the late Neogene and its environment converted to freshwater.^[9] River dolphins likely traveled from the Ganges River basin to the Indus via stream capture within the last five million years. The split between the two species is estimated to have occurred around 550,000 years ago based on mitochondrial DNA.^[12]

Description

Full body (top) and skull of Indus river dolphin

South Asian river dolphins are stocky with broad, squared-off pectoral fins; elongated, slender rostrums (snouts); and tiny triangular dorsal fins. Their neck joints give them great flexibility.^[3]^[13]^[14] Unusual among cetaceans, the blowhole is slit-shaped.^[14] The finger bones can also be seen through the flippers.^[13] South Asian river dolphins possess some features that are "primitive" for a cetacean, such as a cecum connected to the gut and air sacs near the blowhole. The testes of the males are located closer to the underside than in marine dolphins and descend more.^[15] Their skin ranges from grey to greyish-brown in colour, though the rostrum and surrounding areas may have some pinkish colouration. The Indus species tends to be more brownish.^[3]

In one study sampling 46 Ganges river dolphins, the maximum length and weight recorded were 267 cm (8.76 ft) and 108 kg (238 lb). For the Indus species, the maximum length and weight were 241 cm (7.91 ft) and 120 kg (260 lb) (80 individuals sampled). Female Ganges dolphins are generally longer than Indus dolphins of both sexes, while male Ganges dolphins are shorter than Indus dolphins of both sexes. Indus dolphins tend to be proportionally heavier than Ganges dolphins, independent of sex.^[3]

South Asian river dolphin skulls have unusual features. The maxilla (fixed upper jawbone) has pneumatic extensions or "crests" on each side which curve around the melon and protrude forward over the rostrum. These likely help them focus their echolocation signals in their riverine environment.^[16] The Ganges species also has a protrusion near the frontal suture, which distinguishes it from the Indus species.^[3] The teeth of South Asian river dolphins are curved and longer in the front, where they remain exposed when the jaws are closed.^[14] Indus dolphins have more teeth than Ganges dolphins, averaging 33.2 teeth in the upper jaw and the 32.9 in the lower jaw, as compared to 28.4 in the upper jaw and 29.4 in the lower.^[3]

Living in murky waters, South Asian river dolphins are nearly blind, their tiny eyes having flattened corneas and no lens. The retina—which connects to a reduced optic nerve—does not form images but instead merely discerns light. The animal relies on a sphincter-like muscle around the eye to control access to the retina and prevent light scattering, similar to a pinhole.^[17] The ears are adapted to hearing low frequencies, having a short, flattened cochlea with widely spaced spirals.^[8]

Distribution and habitat

South Asian river dolphins inhabit the northern waterways of the Indian subcontinent. Ganges river dolphins live in the Ganges, Brahmaputra, Meghna, Karnaphuli, and Sangu rivers and their tributaries. Their range extends from the Himalayan foothills to the Ganges Delta, across the countries of Nepal, India and Bangladesh.^[3]^[14] It is unknown if they are present in Bhutan.^[18] Outflows of freshwater into the Bay of Bengal have allowed them to swim along the coast, and there is at least one record of an individual entering the Budhabalanga River, around 300 km (190 mi) southwest of the Ganges Delta.^[19] This species has maintained much of its range since the 19th century but has disappeared from some northern and western rivers and waterways.^[3]

The Indus river dolphin mainly lives in the Indus River of Pakistan, with three subpopulations between the Chashma, Taunsa, Guddu, and Sukkur barrages. Two other populations exist south of Sukkur and in the Beas River of India.^[3]^[20] In the 19th century, this species was reported to have occurred throughout the Indus River system, from the Indus River Delta north to Kalabagh just south of the Himalayas, including all the main tributaries.^[3] The Indus river dolphin is reported to have disappeared between the Jinnah and Chashma barrages after 2001.^[20]

South Asian river dolphins inhabit major river channels during the dry season and travel to smaller tributaries for the monsoon. They are most commonly found in stream pools, meanders, and confluences, and around river islands and shoals, which produce relatively stable waters.^[19] They can be found in pools over 30 m (98 ft) deep, but usually dwell in shallower water.^[14]

Behaviour and life history

South Asian river dolphins appear to be active throughout the day. Living in flowing waters, they swim almost constantly with only brief periods of sleep, which add up to seven hours per day.^[21] They swim on their sides when in shallow water.^[22] River dolphins generally surface with the rostrum, head, and dorsal fin breaking the water and rarely breach or raise the tail fluke, though surface activity can vary based on age, distance from shore and time of day. Diving may last as long as eight minutes among adults and subadults; dives of newborns and juveniles are not as long.^[23]

Two dolphins leaping out of water — Indus river dolphins leaping

River dolphins are typically seen alone or in groups of up to 10 individuals, though enough natural resources may attract up to 30 dolphins. Individuals do not appear to have strong social bonds, outside of mothers and calves.^[14] Living in shallow river environments with acoustic obstacles, these dolphins echolocate using repetitive clicks spaced 10 to 100 milliseconds apart.^[24]^[25] Their clicks are about one octave below those of oceanic toothed whales of comparable size, meaning that they provide less information about the location of an object, but the dolphins' maxillary crests likely compensate by providing greater directional sensitivity.^[16] Vocalisations used for communication include bursts and twitterings.^[26]

River dolphins feed mainly on fish and shrimp. In one meta study, around 46% of prey items were found to be bottom-dwelling species, while 31% were near the surface, and 23% occupied the middle of the column. The most frequently taken prey are bagrid catfish, barbs, glass perches, spiny eels, gobies, and prawns. When hunting at the surface, dolphins listen for the movements of schooling fish which are then herded with spins, side-swimming, and lobtailing. Echolocation signals are not frequently used at the surface, since many fish at this level can hear ultrasound. At the mid-surface level, the dolphins use more echolocation clicks to find prey hidden in clutter and vegetation as far as 20 m (66 ft) away. They flush out bottom-dwelling prey by digging around.^[22]

Little is known about reproduction in these river dolphins.^[14] Courtship and mating behaviour for the Ganges species has been documented from March to May, when the water level is lower, and involves multiple males chasing one female and ends with one of the males earning the right to mate.^[15] Calves are born around a year later.^[27] Births in the Ganges river dolphin appear to be most frequent between December and January and between March and May. For Indus river dolphins, newborns are most commonly seen between April and May.^[14] Indus river dolphins calves are around 70 cm (28 in) long at birth and may nurse for up to a year. They eat their first solid food within a couple months. South Asian river dolphins reach sexual maturity at around ten years, though males may not reach their adult size until 20 years.^[28] Growth layers in the teeth suggest South Asian river dolphins can live up to 30 years.^[29]

Conservation

Man standing in water while holding dolphin — Man holding Ganges river dolphin in Bhagalpur

As of 2022, the IUCN Red List of mammals lists both South Asian river dolphins as endangered.^[18]^[30] Two assessments in 2014 and 2015 estimated populations of 3,500 for the Ganges river dolphin and 1,500 for the Indus river dolphin.^[19]^[31] The Ganges species appears to be decreasing, while the Indus species may be increasing.^[18]^[30] The habitat of these river dolphins intersects with some of the most densely populated areas, leading to intense competition for water and resources.^[19]^[31]^[32]

The creation of dams and barrages in the Indus River system have heavily fragmented the range of the Indus river dolphin, leading to a population decline of 80% since the 19th century.^[31] Around 50 such structures have been built in the historical range of the Ganges species.^[19] Fragmentation of populations makes these dolphins more vulnerable to inbreeding.^[32] The heavy extraction of water in these dense populations also puts the dolphins at risk.^[19]

River dolphins accumulate high amounts of persistent organic pollutants, pesticides, and heavy metals in their system due to being at the top of their riverine food web.^[19]^[31] Hence, they are seen as bioindicators for the health of river systems.^[19] Fishermen compete with these animals for fish of certain sizes.^[32] Dolphins captured in fishing nets are usually accidental, but dolphin oil is sought after as a fish lure, and thus fishermen may be motivated to kill caught dolphins.^[19] Being nearly blind and relying on echolocation for navigation, river dolphins are also negatively affected by noise pollution from boats.^[33]

South Asian river dolphins are protected by law in all the states they inhabit. They can be found in numerous protected areas,^[18]^[30] including ones established specifically for them, such as the Indus Dolphin Reserve in Pakistan and the Vikramshila Gangetic Dolphin Sanctuary in India.^[19]^[31] International trade is prohibited by the listing of the South Asian river dolphins on Appendix I of the Convention on International Trade in Endangered Species.^[34] The Ganges and Indus river dolphins are considered to be the national aquatic animals of India and Pakistan respectively.^[35]^[36]

References

^ "Platanista Wagler 1830 (toothed whale)". Paleobiology Database. Archived from the original on 12 December 2021. Retrieved 26 March 2018.
^ Wilson, D. E.; Reeder, D. M., eds. (2005). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. ISBN 978-0-8018-8221-0. OCLC 62265494.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l Braulik, G. T.; Archer, F. I.; Khan, U.; Imran, M.; Sinha, R. K.; Jefferson, T. A.; Donovan, C.; Graves, J. A. (2021). "Taxonomic revision of the South Asian River dolphins (Platanista): Indus and Ganges river dolphins are separate species". Marine Mammal Science. 37 (3): 1022–1059. Bibcode:2021MMamS..37.1022B. doi:10.1111/mms.12801. hdl:10023/21691.
^ "Platanista". Merriam-Webster.com Dictionary. Archived from the original on 22 September 2022. Retrieved 22 September 2022.
^ Pilleri, G.; Marcuzzi, G.; Pilleri, O. (1982). "Speciation in the Platanistoidea, systematic, zoogeographical and ecological observations on recent species". Investigations on Cetacea. 14: 15–46.
^ ^a ^b ^c Braulik, G. T.; Barnett, R.; Odon, V.; Islas-Villanueva, V.; Hoelzel, A. R.; Graves, J. A. (2014). "One Species or Two? Vicariance, lineage divergence and low mtDNA diversity in geographically isolated populations of South Asian River Dolphin". Journal of Mammalian Evolution. 22 (1): 111–120. doi:10.1007/s10914-014-9265-6. S2CID 14113756.
^ Rice, D. (1998). Marine Mammals of the World: Systematics and Distribution. Society for Marine Mammalogy. p. 92. ISBN 9781891276033.
^ ^a ^b ^c Viglino, M.; Gaetán, M.; Buono, M. R.; Fordyce, R. E.; Park, T. (2021). "Hearing from the ocean and into the river: the evolution of the inner ear of Platanistoidea (Cetacea: Odontoceti)". Paleobiology. 47 (4): 591–611. Bibcode:2021Pbio...47..591V. doi:10.1017/pab.2021.11. S2CID 233517623. Archived from the original on 5 April 2023. Retrieved 31 October 2022.
^ ^a ^b Hamilton, H.; Caballero, S.; Collins, A. G.; Brownell, R. L. Jr. (2001). "Evolution of river dolphins". Proceedings: Biological Sciences. 268 (1466): 549–556. doi:10.1098/rspb.2000.1385. JSTOR 3068225. PMC 1088639. PMID 11296868.
^ Gatesy, John; Geisler, Jonathan H.; Chang, Joseph; Buell, Carl; Berta, Annalisa; Meredith, Robert W.; Springer, Mark S.; McGowen, Michael R. (2012). "A phylogenetic blueprint for a modern whale" (PDF). Molecular Phylogenetics and Evolution. 66 (2): 479–506. doi:10.1016/j.ympev.2012.10.012. PMID 23103570. Archived (PDF) from the original on 9 June 2015. Retrieved 4 September 2015.
^ McGowen, M. R.; Tsagkogeorga, G.; Álvarez-Carretero, S.; et al. (2020). "Phylogenomic resolution of the cetacean tree of life using target sequence capture". Systematic Biology. 69 (3): 479–501. doi:10.1093/sysbio/syz068. PMC 7164366. PMID 31633766.
^ Braulik, G.; Barnett, R.; Odon, V.; Islas-Villanueva, V.; Hoelzel, R.; Graves, J. A. (2015). "One species or two? Vicariance, lineage divergence and low mtDNA diversity in geographically isolated populations of South Asian river dolphin". Journal of Mammalian Evolution. 22 (1): 111–120. doi:10.1007/s10914-014-9265-6. S2CID 14113756.
^ ^a ^b Cassens, I.; Vicario, S.; Waddell, V. G.; Milinkovitch, M. C.; et al. (2000). "Independent adaptation to riverine habitats allowed survival of ancient cetacean lineages". PNAS. 97 (21): 11343–11347. Bibcode:2000PNAS...9711343C. doi:10.1073/pnas.97.21.11343. PMC 17202. PMID 11027333.
^ ^a ^b ^c ^d ^e ^f ^g ^h Jefferson, Thomas A.; Webber, Marc A.; Pitman, Robert L. (2015). Marine Mammals of the World: A Comprehensive Guide to Their Identification (2nd ed.). Academic Press. pp. 346–349. ISBN 978-0-12-409542-7.
^ ^a ^b Sinha, R. K.; Kannan, K. (2014). "Ganges river dolphin: an overview of biology, ecology, and conservation status in India (Supplementary material 1)". Ambio. 43 (8): 1029–1046. Bibcode:2014Ambio..43.1029S. doi:10.1007/s13280-014-0534-7. PMC 4235892. PMID 24924188.
^ ^a ^b Jensen, F. H.; Rocco, A.; Mansur, R. M.; Smith, B. D.; Janik, V. M.; Madsen, P. T. (2013). "Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges river dolphins in a shallow, acoustically complex habitat". PLOS ONE. 8 (4): e59284. Bibcode:2013PLoSO...859284J. doi:10.1371/journal.pone.0059284. PMC 3616034. PMID 23573197.
^ Herald, Earl S.; Brownell, Robert L.; Frye, Fredric L.; Morris, Elkan J.; Evans, William E.; Scott, Alan B. (1969). "Blind river dolphin: first side-swimming cetacean". Science. 166 (3911): 1408–1410. Bibcode:1969Sci...166.1408H. doi:10.1126/science.166.3911.1408. JSTOR 1727285. PMID 5350341. S2CID 5670792. Archived from the original on 2 August 2023. Retrieved 1 December 2019.
^ ^a ^b ^c ^d Kelkar, N.; Smith, B. D.; Alom, M. Z.; Dey, S.; Paudel, S.; Braulik, G. T. (2022). "Platanista gangetica". IUCN Red List of Threatened Species. 2022: e.T41756A50383346. doi:10.2305/IUCN.UK.2022-1.RLTS.T41756A50383346.en. Retrieved 17 October 2022.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j Sinha, R. K.; Kannan, K. (2014). "Ganges river dolphin: an overview of biology, ecology, and conservation status in India". Ambio. 43 (8): 1029–1046. Bibcode:2014Ambio..43.1029S. doi:10.1007/s13280-014-0534-7. PMC 4235892. PMID 24924188.
^ ^a ^b Aisha, H.; Khan, U. (April 2021). Abundance survey for Indus river dolphin, Final Report (Report). IWC Small Cetacean Fund. doi:10.13140/RG.2.2.24280.83207.
^ Pilleri, G. (1979). "The blind Indus dolphin, Platanista indi". Endeavour. 3 (2): 48–56. doi:10.1016/0160-9327(79)90066-8.
^ ^a ^b Kelhar, N.; Dey, S.; Deshpande, K.; Choudhary, S. K.; Dey, S.; Morisaka, T. (2018). "Foraging and feeding ecology of Platanista: an integrative review". Mammal Review. 48 (3): 194–208. doi:10.1111/mam.12124. S2CID 89753459.
^ Sinha, R. K.; Sinha, S.; Sharma, G.; Kedia, D. K. (2010). "Surfacing and diving behaviour of free-ranging Ganges river dolphin, Platanista gangetica gangetica". Current Science. 98 (2): 230–236. JSTOR 24111514.
^ Jensen, F. H.; Rocco, A.; Mansur, R. M.; Smith, B. D.; Janik, V. M.; Madsen, P. T. (2013). "Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges river dolphins in a shallow, acoustically complex habitat". PLOS ONE. 8 (4): e59284. Bibcode:2013PLoSO...859284J. doi:10.1371/journal.pone.0059284. PMC 3616034. PMID 23573197.
^ Sugimatsu, H.; Ura, T.; Mizuno, K.; Asada, A. (2012). "Study of acoustic characteristics of Ganges river dolphin calf using ehcolocation clicks recorded during long-term in-situ observation". 2012 Oceans. Oceans 2012 Conference. pp. 1–7. doi:10.1109/OCEANS.2012.6405029. ISBN 978-1-4673-0829-8. S2CID 22758375.
^ Mizue, K.; Masaharu, N.; Akira, T. (1971). "The underwater sounds of Ganges River dolphin (Platanista gangetica)". The Scientific Reports of the Whales Research Institute. 23: 123–128.
^ Smith, B. D.; Braulik, G. T. (2015). "Susu and Bhulan". In Perrin, William F.; Wursig, Bernd; Thewissen, J. G. M. (eds.). Encyclopedia of Marine Mammals. Academic Press. pp. 1135–1139. ISBN 978-0-12-804327-1.
^ Kasuya, T. (1972). "Some information on the growth of the Ganges dolphin with a comment on the Indus dolphin". The Scientific Reports of the Whales Research Institute. 24: 87–108.
^ Lockyer, C. H.; Braulik, G. T. (2014). "An evaluation of age estimation using teeth from South Asian River dolphins (Platanistidae)". NAMMCO Scientific Publications. 10. doi:10.7557/3.3268. hdl:10023/20641.
^ ^a ^b ^c Braulik, G. T.; Khan, U.; Malik, M.; Aisha, H. (2022). "Platanista minor". IUCN Red List of Threatened Species. 2022: e.T41757A50383490. doi:10.2305/IUCN.UK.2022-1.RLTS.T41757A50383490.en. Retrieved 14 October 2022.
^ ^a ^b ^c ^d ^e Braulik, Gill T.; Noureen, Uzma; Arshad, Masood; Reeves, Randall R. (2015). "Review of status, threats, and conservation management options for the endangered Indus River blind dolphin". Biological Conservation. 192: 30–41. Bibcode:2015BCons.192...30B. doi:10.1016/j.biocon.2015.09.008. ISSN 0006-3207. Archived from the original on 22 September 2022. Retrieved 27 August 2021.
^ ^a ^b ^c Paudel, S.; Koprowski, J. L. (2020). "Factors affecting the persistence of endangered Ganges River dolphins (Platanista gangetica gangetica)". Ecology and Evolution. 10 (6): 3138–3148. Bibcode:2020EcoEv..10.3138P. doi:10.1002/ece3.6102. PMC 7083702. PMID 32211183.
^ Dey, M.; Krishnaswamy, J.; Morisaka, T.; Kelkar, N. (2019). "Interacting effects of vessel noise and shallow river depth elevate metabolic stress in Ganges river dolphins". Scientific Reports. 9 (15426): 15426. Bibcode:2019NatSR...915426D. doi:10.1038/s41598-019-51664-1. PMC 6817857. PMID 31659202. S2CID 204918073.
^ "Appendix I". Convention on International Trade in Endangered Species of Wild Fauna and Flora. 22 June 2022. Archived from the original on 5 October 2011. Retrieved 6 January 2023.
^ "National Aquatic Animal – National Symbols – Know India: National Portal of India". National Portal of India. Archived from the original on 22 January 2013. Retrieved 23 March 2012.
^ "National Symbols of Pakistan". Government of Pakistan. Archived from the original on 28 November 2016. Retrieved 23 October 2016.

External links

Media related to Platanista at Wikimedia Commons

[fossilworks-1] "Platanista Wagler 1830 (toothed whale)". Paleobiology Database. Archived from the original on 12 December 2021. Retrieved 26 March 2018.

[2] Wilson, D. E.; Reeder, D. M., eds. (2005). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. ISBN 978-0-8018-8221-0. OCLC 62265494.

[Braulik_al20212-3] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l Braulik, G. T.; Archer, F. I.; Khan, U.; Imran, M.; Sinha, R. K.; Jefferson, T. A.; Donovan, C.; Graves, J. A. (2021). "Taxonomic revision of the South Asian River dolphins (Platanista): Indus and Ganges river dolphins are separate species". Marine Mammal Science. 37 (3): 1022–1059. Bibcode:2021MMamS..37.1022B. doi:10.1111/mms.12801. hdl:10023/21691.

[4] "Platanista". Merriam-Webster.com Dictionary. Archived from the original on 22 September 2022. Retrieved 22 September 2022.

[Pilleri-5] Pilleri, G.; Marcuzzi, G.; Pilleri, O. (1982). "Speciation in the Platanistoidea, systematic, zoogeographical and ecological observations on recent species". Investigations on Cetacea. 14: 15–46.

[Braulik_al2014-6] Braulik, G. T.; Barnett, R.; Odon, V.; Islas-Villanueva, V.; Hoelzel, A. R.; Graves, J. A. (2014). "One Species or Two? Vicariance, lineage divergence and low mtDNA diversity in geographically isolated populations of South Asian River Dolphin". Journal of Mammalian Evolution. 22 (1): 111–120. doi:10.1007/s10914-014-9265-6. S2CID 14113756.

[7] Rice, D. (1998). Marine Mammals of the World: Systematics and Distribution. Society for Marine Mammalogy. p. 92. ISBN 9781891276033.

[Viglino-8] Viglino, M.; Gaetán, M.; Buono, M. R.; Fordyce, R. E.; Park, T. (2021). "Hearing from the ocean and into the river: the evolution of the inner ear of Platanistoidea (Cetacea: Odontoceti)". Paleobiology. 47 (4): 591–611. Bibcode:2021Pbio...47..591V. doi:10.1017/pab.2021.11. S2CID 233517623. Archived from the original on 5 April 2023. Retrieved 31 October 2022.

[Hamilton-9] Hamilton, H.; Caballero, S.; Collins, A. G.; Brownell, R. L. Jr. (2001). "Evolution of river dolphins". Proceedings: Biological Sciences. 268 (1466): 549–556. doi:10.1098/rspb.2000.1385. JSTOR 3068225. PMC 1088639. PMID 11296868.

[10] Gatesy, John; Geisler, Jonathan H.; Chang, Joseph; Buell, Carl; Berta, Annalisa; Meredith, Robert W.; Springer, Mark S.; McGowen, Michael R. (2012). "A phylogenetic blueprint for a modern whale" (PDF). Molecular Phylogenetics and Evolution. 66 (2): 479–506. doi:10.1016/j.ympev.2012.10.012. PMID 23103570. Archived (PDF) from the original on 9 June 2015. Retrieved 4 September 2015.

[11] McGowen, M. R.; Tsagkogeorga, G.; Álvarez-Carretero, S.; et al. (2020). "Phylogenomic resolution of the cetacean tree of life using target sequence capture". Systematic Biology. 69 (3): 479–501. doi:10.1093/sysbio/syz068. PMC 7164366. PMID 31633766.

[12] Braulik, G.; Barnett, R.; Odon, V.; Islas-Villanueva, V.; Hoelzel, R.; Graves, J. A. (2015). "One species or two? Vicariance, lineage divergence and low mtDNA diversity in geographically isolated populations of South Asian river dolphin". Journal of Mammalian Evolution. 22 (1): 111–120. doi:10.1007/s10914-014-9265-6. S2CID 14113756.

[Cassens2000-13] Cassens, I.; Vicario, S.; Waddell, V. G.; Milinkovitch, M. C.; et al. (2000). "Independent adaptation to riverine habitats allowed survival of ancient cetacean lineages". PNAS. 97 (21): 11343–11347. Bibcode:2000PNAS...9711343C. doi:10.1073/pnas.97.21.11343. PMC 17202. PMID 11027333.

[Jefferson-14] ^ ^a ^b ^c ^d ^e ^f ^g ^h Jefferson, Thomas A.; Webber, Marc A.; Pitman, Robert L. (2015). Marine Mammals of the World: A Comprehensive Guide to Their Identification (2nd ed.). Academic Press. pp. 346–349. ISBN 978-0-12-409542-7.

[supplemantary-15] Sinha, R. K.; Kannan, K. (2014). "Ganges river dolphin: an overview of biology, ecology, and conservation status in India (Supplementary material 1)". Ambio. 43 (8): 1029–1046. Bibcode:2014Ambio..43.1029S. doi:10.1007/s13280-014-0534-7. PMC 4235892. PMID 24924188.

[Jensen-16] Jensen, F. H.; Rocco, A.; Mansur, R. M.; Smith, B. D.; Janik, V. M.; Madsen, P. T. (2013). "Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges river dolphins in a shallow, acoustically complex habitat". PLOS ONE. 8 (4): e59284. Bibcode:2013PLoSO...859284J. doi:10.1371/journal.pone.0059284. PMC 3616034. PMID 23573197.

[:0-17] Herald, Earl S.; Brownell, Robert L.; Frye, Fredric L.; Morris, Elkan J.; Evans, William E.; Scott, Alan B. (1969). "Blind river dolphin: first side-swimming cetacean". Science. 166 (3911): 1408–1410. Bibcode:1969Sci...166.1408H. doi:10.1126/science.166.3911.1408. JSTOR 1727285. PMID 5350341. S2CID 5670792. Archived from the original on 2 August 2023. Retrieved 1 December 2019.

[iucn_status_2022-18] Kelkar, N.; Smith, B. D.; Alom, M. Z.; Dey, S.; Paudel, S.; Braulik, G. T. (2022). "Platanista gangetica". IUCN Red List of Threatened Species. 2022: e.T41756A50383346. doi:10.2305/IUCN.UK.2022-1.RLTS.T41756A50383346.en. Retrieved 17 October 2022.

[Sinha2014-19] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j Sinha, R. K.; Kannan, K. (2014). "Ganges river dolphin: an overview of biology, ecology, and conservation status in India". Ambio. 43 (8): 1029–1046. Bibcode:2014Ambio..43.1029S. doi:10.1007/s13280-014-0534-7. PMC 4235892. PMID 24924188.

[IWC-20] Aisha, H.; Khan, U. (April 2021). Abundance survey for Indus river dolphin, Final Report (Report). IWC Small Cetacean Fund. doi:10.13140/RG.2.2.24280.83207.

[21] Pilleri, G. (1979). "The blind Indus dolphin, Platanista indi". Endeavour. 3 (2): 48–56. doi:10.1016/0160-9327(79)90066-8.

[feeding-22] Kelhar, N.; Dey, S.; Deshpande, K.; Choudhary, S. K.; Dey, S.; Morisaka, T. (2018). "Foraging and feeding ecology of Platanista: an integrative review". Mammal Review. 48 (3): 194–208. doi:10.1111/mam.12124. S2CID 89753459.

[23] Sinha, R. K.; Sinha, S.; Sharma, G.; Kedia, D. K. (2010). "Surfacing and diving behaviour of free-ranging Ganges river dolphin, Platanista gangetica gangetica". Current Science. 98 (2): 230–236. JSTOR 24111514.

[Jensen22-24] Jensen, F. H.; Rocco, A.; Mansur, R. M.; Smith, B. D.; Janik, V. M.; Madsen, P. T. (2013). "Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges river dolphins in a shallow, acoustically complex habitat". PLOS ONE. 8 (4): e59284. Bibcode:2013PLoSO...859284J. doi:10.1371/journal.pone.0059284. PMC 3616034. PMID 23573197.

[25] Sugimatsu, H.; Ura, T.; Mizuno, K.; Asada, A. (2012). "Study of acoustic characteristics of Ganges river dolphin calf using ehcolocation clicks recorded during long-term in-situ observation". 2012 Oceans. Oceans 2012 Conference. pp. 1–7. doi:10.1109/OCEANS.2012.6405029. ISBN 978-1-4673-0829-8. S2CID 22758375.

[26] Mizue, K.; Masaharu, N.; Akira, T. (1971). "The underwater sounds of Ganges River dolphin (Platanista gangetica)". The Scientific Reports of the Whales Research Institute. 23: 123–128.

[Perrin2015-27] Smith, B. D.; Braulik, G. T. (2015). "Susu and Bhulan". In Perrin, William F.; Wursig, Bernd; Thewissen, J. G. M. (eds.). Encyclopedia of Marine Mammals. Academic Press. pp. 1135–1139. ISBN 978-0-12-804327-1.

[28] Kasuya, T. (1972). "Some information on the growth of the Ganges dolphin with a comment on the Indus dolphin". The Scientific Reports of the Whales Research Institute. 24: 87–108.

[29] Lockyer, C. H.; Braulik, G. T. (2014). "An evaluation of age estimation using teeth from South Asian River dolphins (Platanistidae)". NAMMCO Scientific Publications. 10. doi:10.7557/3.3268. hdl:10023/20641.

[IUCN-30] Braulik, G. T.; Khan, U.; Malik, M.; Aisha, H. (2022). "Platanista minor". IUCN Red List of Threatened Species. 2022: e.T41757A50383490. doi:10.2305/IUCN.UK.2022-1.RLTS.T41757A50383490.en. Retrieved 14 October 2022.

[Braulik2015-31] Braulik, Gill T.; Noureen, Uzma; Arshad, Masood; Reeves, Randall R. (2015). "Review of status, threats, and conservation management options for the endangered Indus River blind dolphin". Biological Conservation. 192: 30–41. Bibcode:2015BCons.192...30B. doi:10.1016/j.biocon.2015.09.008. ISSN 0006-3207. Archived from the original on 22 September 2022. Retrieved 27 August 2021.

[Paudel2020-32] Paudel, S.; Koprowski, J. L. (2020). "Factors affecting the persistence of endangered Ganges River dolphins (Platanista gangetica gangetica)". Ecology and Evolution. 10 (6): 3138–3148. Bibcode:2020EcoEv..10.3138P. doi:10.1002/ece3.6102. PMC 7083702. PMID 32211183.

[33] Dey, M.; Krishnaswamy, J.; Morisaka, T.; Kelkar, N. (2019). "Interacting effects of vessel noise and shallow river depth elevate metabolic stress in Ganges river dolphins". Scientific Reports. 9 (15426): 15426. Bibcode:2019NatSR...915426D. doi:10.1038/s41598-019-51664-1. PMC 6817857. PMID 31659202. S2CID 204918073.

[Appendices_{{!}}_CITES-34] "Appendix I". Convention on International Trade in Endangered Species of Wild Fauna and Flora. 22 June 2022. Archived from the original on 5 October 2011. Retrieved 6 January 2023.

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@@ Line 3: / Line 3: @@
 {{Use dmy dates|date=June 2020}}
 {{Automatic taxobox
-| fossil_range = {{Fossil range|0.012|0}} [[Quaternary]] – recent<ref name=fossilworks>{{cite web|title=Platanista Wagler 1830 (toothed whale)|url=http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=63564|website=Paleobiology Database|accessdate=26 March 2018}}</ref>
+| fossil_range = {{Fossil range|0.012|0}} [[Quaternary]] – recent<ref name=fossilworks>{{cite web|title=Platanista Wagler 1830 (toothed whale)|url=https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=63564|website=Paleobiology Database|access-date=26 March 2018|archive-date=12 December 2021|archive-url=https://web.archive.org/web/20211212182152/http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=63564|url-status=live}}</ref>
-| image = The magnificent Ganges River Dolphin.jpg
+| image =Ganges River Dolphin cropped.jpg
 | image_caption = [[Ganges river dolphin]] breaking the surface
 | taxon = Platanista
@@ Line 17: / Line 17: @@
 }}
-'''South Asian river dolphins''' are [[toothed whale]]s in the genus '''''Platanista''''', which inhabit [[fresh water]] habitats in the northern [[Indian subcontinent]]. They were historically considered to be one species (''P. gangetica'') with the [[Ganges river dolphin]] and the [[Indus river dolphin]] being subspecies (''P. g. gangetica'' and ''P. g. minor'' respectively).  Genetic and morphological evidence led to their being described as separate species in 2021. The Ganges and Indus river dolphins are estimated to have [[Split (phylogenetics)|diverged]] 550,000 years ago. They are the only living members of the family [[Platanistidae]] and the superfamily Platanistoidea. Fossils of ancient relatives date to the [[late Oligocene]].
+'''South Asian river dolphins''' are [[toothed whale]]s in the genus '''''Platanista''''', which inhabit the waterways of the [[Indian subcontinent]]. They were historically considered to be one species (''P. gangetica'') with the [[Ganges river dolphin]] and the [[Indus river dolphin]] being subspecies (''P. g. gangetica'' and ''P. g. minor'' respectively).  Genetic and morphological evidence led to their being described as separate species in 2021. The Ganges and Indus river dolphins are estimated to have [[Split (phylogenetics)|diverged]] 550,000 years ago. They are the only living members of the family [[Platanistidae]] and the superfamily Platanistoidea. Fossils of ancient relatives date to the [[late Oligocene]].
-South Asian river dolphins are small but stocky [[cetacean]]s with long snouts or [[Rostrum (anatomy)|rostra]], broad flippers, and small dorsal fins. They have several unusual features. Living in murky river waters, their eyes are tiny and lensless. The dolphins rely instead on [[Animal echolocation|echolocation]] for navigation. The skull has large crests over the [[Melon (cetacean)|melon]], which help direct their echolocation signals. These dolphins prey mainly on fish and shrimp and hunt them throughout the [[water column]]. They are active through the day and are sighted in small groups. Both species are listed as [[Endangered species|endangered]] by the [[IUCN Red List]] of mammals. Major threats include dams, [[Barrage (dam)|barrages]], fishing nets, and both chemical and [[noise pollution|acoustic]] pollution.
+South Asian river dolphins are small but stocky [[cetacean]]s with long snouts or [[Rostrum (anatomy)|rostra]], broad flippers, and small dorsal fins. They have several unusual features. Living in murky river waters, they have eyes that are tiny and lensless; the dolphins rely instead on [[Animal echolocation|echolocation]] for navigation. The skull has large crests over the [[Melon (cetacean)|melon]], which help direct their echolocation signals. These dolphins prey mainly on fish and shrimp and hunt them throughout the [[water column]]. They are active through the day and are sighted in small groups. Both species are listed as [[Endangered species|endangered]] by the [[IUCN Red List]] of mammals. Major threats include dams, [[Barrage (dam)|barrages]], fishing nets, and both chemical and [[noise pollution|acoustic]] pollution.
 ==Taxonomy==
-South Asian river dolphins were traditionally considered to be one species, ''Platanista gangetica'', with the Ganges and Indus River populations being subspecies (''P. g. gangetica'' and ''P. g. minor'', respectively). [[Heinrich Julius Lebeck]] named the Ganges river dolphin ''Delphinus gangeticus'' in 1801, while [[Johann Georg Wagler]] coined the genus name ''Platanista'' in 1830,<ref name="Braulik_al20212">{{Cite journal|last1=Braulik|first1=G. T.|last2=Archer|first2=F. I.|last3=Khan|first3=U.|last4=Imran|first4=M.|last5=Sinha|first5=R. K.|last6=Jefferson|first6=T. A.|last7=Donovan|first7=C.|last8=Graves|first8=J. A.|year=2021|title=Taxonomic revision of the South Asian River dolphins (''Platanista''): Indus and Ganges river dolphins are separate species|journal=Marine Mammal Science|volume=37|issue=3|pages=1022–1059|doi=10.1111/mms.12801|doi-access=free}}</ref> a [[Latin]] word derived from the [[Ancient Greek|Greek]] "platanistēs", which may be related to the Greek words platē ("oar") or platē ("flat, broad").<ref>{{cite web|title=''Platanista''|website=Merriam-Webster.com Dictionary|url=https://www.merriam-webster.com/dictionary/Platanista|accessdate=22 September 2022}}</ref> This name was first given to the Ganges dolphin by [[Pliny the Elder]] in ''[[Naturalis Historia]]'' back in 77 [[Common Era|CE]]. In 1853, [[Richard Owen]] described a specimen from the Indus and considered it to be the same species as the Ganges river dolphin, but a smaller form.<ref name="Braulik_al20212"/>
+South Asian river dolphins were traditionally considered to be one species, ''Platanista gangetica'', with the Ganges and Indus River populations being subspecies (''P. g. gangetica'' and ''P. g. minor'', respectively). [[Heinrich Julius Lebeck]] named the Ganges river dolphin ''Delphinus gangeticus'' in 1801, while [[Johann Georg Wagler]] coined the genus name ''Platanista'' in 1830,<ref name="Braulik_al20212">{{Cite journal|last1=Braulik|first1=G. T.|last2=Archer|first2=F. I.|last3=Khan|first3=U.|last4=Imran|first4=M.|last5=Sinha|first5=R. K.|last6=Jefferson|first6=T. A.|last7=Donovan|first7=C.|last8=Graves|first8=J. A.|year=2021|title=Taxonomic revision of the South Asian River dolphins (''Platanista''): Indus and Ganges river dolphins are separate species|journal=Marine Mammal Science|volume=37|issue=3|pages=1022–1059|doi=10.1111/mms.12801|doi-access=free|bibcode=2021MMamS..37.1022B |hdl=10023/21691|hdl-access=free}}</ref> a [[Latin]] word derived from the [[Ancient Greek|Greek]] "platanistēs", which may be related to the Greek words platē ("oar") or platē ("flat, broad").<ref>{{cite web|title=''Platanista''|website=Merriam-Webster.com Dictionary|url=https://www.merriam-webster.com/dictionary/Platanista|accessdate=22 September 2022|archive-date=22 September 2022|archive-url=https://web.archive.org/web/20220922190833/https://www.merriam-webster.com/dictionary/Platanista|url-status=live}}</ref> This name was first given to the Ganges dolphin by [[Pliny the Elder]] in ''[[Naturalis Historia]]'' back in 77 [[Common Era|CE]]. In 1853, [[Richard Owen]] described a specimen from the Indus and considered it to be the same species as the Ganges river dolphin, but a smaller form.<ref name="Braulik_al20212"/>
 Based on differences in skull and vertebrae structure, blood proteins, and [[lipid]]s, scientists declared them to be separate species in the 1970s.<ref name=Pilleri>{{cite journal |author=Pilleri, G. |author2=Marcuzzi, G. |author3=Pilleri, O. |year=1982 |title=Speciation in the Platanistoidea, systematic, zoogeographical and ecological observations on recent species |journal=Investigations on Cetacea |volume=14 |pages=15–46}}</ref><ref name="Braulik_al2014"/> The results of these studies were criticized for their small sample sizes and the absence of statistical analyses; by the late 1990s, the two populations were again considered to be two subspecies of a single species.<ref>{{cite book|author=Rice, D.|year=1998|title=Marine Mammals of the World: Systematics and Distribution|publisher=Society for Marine Mammalogy|page=92|isbn=9781891276033}}</ref><ref name="Braulik_al2014"/> A 2014 [[mitochondrial DNA]] study found insufficient differences to support their classification as separate species.<ref name="Braulik_al2014">{{Cite journal|year=2014 |title=One Species or Two? Vicariance, lineage divergence and low mtDNA diversity in geographically isolated populations of South Asian River Dolphin |journal=Journal of Mammalian Evolution |volume=22 |issue=1 |pages=111–120 |doi=10.1007/s10914-014-9265-6 |last1=Braulik |first1=G. T. |last2=Barnett |first2=R. |last3=Odon|first3=V.|last4=Islas-Villanueva|first4=V.|last5=Hoelzel|first5=A. R. |last6=Graves|first6=J. A. |s2cid=14113756 |url=https://www.researchgate.net/publication/262524058}}</ref> However, a 2021 study reanalyzed the two populations and found significant genetic divergence and major differences in skull structure; this led to the conclusion that the two were indeed distinct species.<ref name="Braulik_al20212"/>
 ===Evolution===
-South Asian river dolphins are the only surviving members of the family [[Platanistidae]] and the superfamily Platanistoidea.<ref name=Viglino/> They are not closely related to other [[river dolphin]]s of the families [[Lipotidae]], [[Pontoporiidae]], and [[Iniidae]], which all [[convergent evolution|independently adapted]] to freshwater habitats.<ref name=Hamilton/> The following [[cladogram]] is based on Gatesy and colleagues (2012) and McGowen and colleagues (2020); and shows the relationship of South Asian river dolphins to other living toothed whale families:<ref>{{cite journal|author1= Gatesy, John|author2= Geisler, Jonathan H.|author3= Chang, Joseph|author4= Buell, Carl|author5= Berta, Annalisa|author6=Meredith, Robert W. |author7= Springer, Mark S.|author8= McGowen, Michael R.|url=https://www.montclair.edu/profilepages/media/5008/user/Gatesy_et_al._2012_A_phylogenetic_blueprint_for_a_modern_whale.pdf|title=A phylogenetic blueprint for a modern whale|journal=Molecular Phylogenetics and Evolution|year=2012|access-date=4 September 2015|volume=66|issue=2|pages=479–506|doi=10.1016/j.ympev.2012.10.012|pmid=23103570}}</ref><ref>{{cite journal|last1=McGowen|first1=M. R.|last2=Tsagkogeorga|first2=G.|last3=Álvarez-Carretero|first3=S.|display-authors=etal|year=2020|title=Phylogenomic resolution of the cetacean tree of life using target sequence capture|journal=Systematic Biology|volume=69|issue=3|pages=479–501|doi=10.1093/sysbio/syz068|pmid=31633766 |pmc=7164366 }}</ref>
+South Asian river dolphins are the only surviving members of the family [[Platanistidae]] and the superfamily Platanistoidea.<ref name=Viglino/> They are not closely related to other [[river dolphin]]s of the families [[Lipotidae]], [[Pontoporiidae]], and [[Iniidae]], which all [[convergent evolution|independently adapted]] to freshwater habitats.<ref name=Hamilton/> The following [[cladogram]] is based on Gatesy and colleagues (2012) and McGowen and colleagues (2020); and shows the relationship of South Asian river dolphins to other living toothed whale families:<ref>{{cite journal|author1=Gatesy, John|author2=Geisler, Jonathan H.|author3=Chang, Joseph|author4=Buell, Carl|author5=Berta, Annalisa|author6=Meredith, Robert W.|author7=Springer, Mark S.|author8=McGowen, Michael R.|url=https://www.montclair.edu/profilepages/media/5008/user/Gatesy_et_al._2012_A_phylogenetic_blueprint_for_a_modern_whale.pdf|title=A phylogenetic blueprint for a modern whale|journal=Molecular Phylogenetics and Evolution|year=2012|access-date=4 September 2015|volume=66|issue=2|pages=479–506|doi=10.1016/j.ympev.2012.10.012|pmid=23103570|archive-date=9 June 2015|archive-url=https://web.archive.org/web/20150609233831/https://www.montclair.edu/profilepages/media/5008/user/Gatesy_et_al._2012_A_phylogenetic_blueprint_for_a_modern_whale.pdf|url-status=live}}</ref><ref>{{cite journal|last1=McGowen|first1=M. R.|last2=Tsagkogeorga|first2=G.|last3=Álvarez-Carretero|first3=S.|display-authors=etal|year=2020|title=Phylogenomic resolution of the cetacean tree of life using target sequence capture|journal=Systematic Biology|volume=69|issue=3|pages=479–501|doi=10.1093/sysbio/syz068|pmid=31633766 |pmc=7164366 }}</ref>
 {{Clade|style=font-size:85%;line-height:100%;width:580px;
                      |label1=&nbsp;'''[[Toothed whales]]'''&nbsp;
                      |1={{Clade
-                        |2={{Clade
+                        |1={{Clade
-                              |2=&nbsp;[[Sperm whale]]s (Physeteridae) [[File:Physeter macrocephalus NOAA.jpg|50 px]]
+                              |1=&nbsp;[[Sperm whale]]s (Physeteridae) [[File:Physeter macrocephalus NOAA.jpg|50 px]]
-                              |1=&nbsp;[[Dwarf sperm whale]]s (Kogiidae)
+                              |2=&nbsp;[[Dwarf sperm whale]]s (Kogiidae) [[File:Kogia sima (transparent background).png|50 px]]
                               }}
-                           |1={{Clade
+                           |2={{Clade
-                              |2=&nbsp;'''South Asian river dolphins''' (Platanistidae)
+                              |1=&nbsp;'''South Asian river dolphins''' (Platanistidae) [[File:Ganges.png|50 px]]
-                              |1={{Clade
+                              |2={{Clade
-                                 |2=&nbsp;[[Beaked whale]]s (Ziphiidae) [[File:Ziphius cavirostris NOAA.jpg|50 px]]
+                                 |1=&nbsp;[[Beaked whale]]s (Ziphiidae) [[File:Ziphius cavirostris NOAA.jpg|50 px]]
-                                 |1={{Clade
+                                 |2={{Clade
-                                    |label2=&nbsp;South American river dolphins&nbsp;
+                                    |label1=&nbsp;South American river dolphins&nbsp;
-                                    |2={{Clade
-                                       |2=&nbsp;[[Pontoporiidae]] [[File:Pontoporia blainvillei.jpg|50 px]]
-                                       |1=&nbsp; [[Iniidae]]
-                                       }}
-                                    |label1=&nbsp;[[Delphinoidea]]&nbsp;
                                     |1={{Clade
-                                       |2=&nbsp;[[Oceanic dolphins]] (Delphinidae) [[File:Orcinus orca NOAA 2.jpg|50 px]]
+                                       |1=&nbsp;[[Pontoporiidae]] [[File:Pontoporia blainvillei.jpg|50 px]]
-                                       |1={{Clade
+                                       |2=&nbsp; [[Iniidae]] [[File:Inia geoffrensis.jpg|50 px]]
-                                          |2=&nbsp;[[Porpoise]]s&nbsp;(Phocoenidae)
+                                       }}
-                                          |1=&nbsp;[[beluga whale|Belugas]], [[narwhal]]s (Monodontidae) [[File:Delphinapterus leucas NOAA.jpg|50 px]]
+                                    |label2=&nbsp;[[Delphinoidea]]&nbsp;
+                                    |2={{Clade
+                                       |1=&nbsp;[[Oceanic dolphins]] (Delphinidae) [[File:Orcinus orca NOAA 2.jpg|50 px]]
+                                       |2={{Clade
+                                          |1=&nbsp;[[Porpoise]]s&nbsp;(Phocoenidae) [[File:Vaquita swimming through the void. (Phocoena Sinus).png|50 px]]
+                                          |2=&nbsp;[[beluga whale|Belugas]], [[narwhal]]s (Monodontidae) [[File:Delphinapterus leucas NOAA.jpg|50 px]]
 }} }} }} }} }} }} }}
-Several fossil species have been classified under Platanistoidea, the earliest of which date back to the [[late Oligocene]] ({{circa|25}} million years ago). The number of species peaked around the [[early Miocene]] ({{circa|19}} million years ago) and declined afterward. Examples of ancient platanistids include the genera ''[[Otekaikea]]'' and ''[[Waipatia]]'' and the species ''[[Awamokoa tokarahi]]'' of late Oligocene New Zealand, the family [[Allodelphinidae]] of early Miocene North Pacific, and ''[[Notocetus vanbenedeni]]'' and ''[[Aondelphis talen]]'' of early Miocene Patagonia. Platanistidae fossils have been found in Miocene deposits in Europe and North America. Fossil Platanistoidea showed a diversity of [[cochlea]] shapes, though ''Platanista'' was unusual in that it developed flatter spirals with larger gaps between them.<ref name=Viglino>{{cite journal|last1=Viglino|first1=M.|last2=Gaetán|first2=M.|last3=Buono|first3=M. R.|last4=Fordyce|first4=R. E.|last5=Park|first5=T.|year=2021|title=Hearing from the ocean and into the river: the evolution of the inner ear of Platanistoidea (Cetacea: Odontoceti)|journal=Paleobiology|volume=47|issue=4|pages=591–611|doi=10.1017/pab.2021.11|bibcode=2021Pbio...47..591V |s2cid=233517623|url=https://zenodo.org/record/4480277}}</ref>
+Several fossil species have been classified under Platanistoidea, the earliest of which date back to the [[late Oligocene]] ({{circa|25}} million years ago). The number of species peaked around the [[early Miocene]] ({{circa|19}} million years ago) and declined afterward. Examples of ancient platanistids include the genera ''[[Otekaikea]]'' and ''[[Waipatia]]'' and the species ''[[Awamokoa tokarahi]]'' of late Oligocene New Zealand, the family [[Allodelphinidae]] of early Miocene North Pacific, and ''[[Notocetus vanbenedeni]]'' and ''[[Aondelphis talen]]'' of early Miocene Patagonia. Platanistidae fossils have been found in Miocene deposits in Europe and North America. Fossil Platanistoidea showed a diversity of [[cochlea]] shapes, though ''Platanista'' was unusual in that it developed flatter spirals with larger gaps between them.<ref name=Viglino>{{cite journal|last1=Viglino|first1=M.|last2=Gaetán|first2=M.|last3=Buono|first3=M. R.|last4=Fordyce|first4=R. E.|last5=Park|first5=T.|year=2021|title=Hearing from the ocean and into the river: the evolution of the inner ear of Platanistoidea (Cetacea: Odontoceti)|journal=Paleobiology|volume=47|issue=4|pages=591–611|doi=10.1017/pab.2021.11|bibcode=2021Pbio...47..591V|s2cid=233517623|url=https://zenodo.org/record/4480277|access-date=31 October 2022|archive-date=5 April 2023|archive-url=https://web.archive.org/web/20230405215841/https://zenodo.org/record/4480277|url-status=live}}</ref>
 During the middle Miocene, the ancestor of ''Platanista'' entered the [[Indo-Gangetic Plain]], then covered by [[Inland sea (geology)|inland sea]]s, and remained there when sea levels dropped in the late [[Neogene]] and its environment converted to freshwater.<ref name=Hamilton>{{cite journal|last1=Hamilton|first1=H.|last2=Caballero|first2=S.|last3=Collins|first3=A. G.|last4=Brownell |first4=R. L. Jr.|year=2001|title=Evolution of river dolphins|journal=Proceedings: Biological Sciences|volume=268|issue=1466|pages=549–556|doi=10.1098/rspb.2000.1385|jstor=3068225|pmid=11296868|pmc=1088639}}</ref> River dolphins likely traveled from the [[Ganges River]] basin to the [[Indus River|Indus]] via [[stream capture]] within the last five million years. The [[Split (phylogenetics)|split]] between the two species is estimated to have occurred around 550,000 years ago based on mitochondrial DNA.<ref>{{cite journal|last1=Braulik|first1=G.|last2=Barnett|first2=R.|last3=Odon|first3=V.|last4=Islas-Villanueva|first4=V.|last5=Hoelzel|first5=R.|last6=Graves|first6=J. A.|year=2015|title=One species or two? Vicariance, lineage divergence and low mtDNA diversity in geographically isolated populations of South Asian river dolphin|journal=Journal of Mammalian Evolution|volume=22|issue=1|pages=111–120|doi=10.1007/s10914-014-9265-6|s2cid=14113756}}</ref>
@@ Line 69: / Line 69: @@
 South Asian river dolphin skulls have unusual features. The [[maxilla]] (fixed upper jawbone) has [[Skeletal pneumaticity|pneumatic]] extensions or "crests" on each side which curve around the [[Melon (cetacean)|melon]] and protrude forward over the rostrum. These likely help them focus their echolocation signals in their riverine environment.<ref name="Jensen">{{cite journal|last1=Jensen|first1=F. H.|last2=Rocco|first2=A.|last3=Mansur|first3=R. M.|last4=Smith|first4=B. D.|last5=Janik|first5=V. M.|last6=Madsen|first6=P. T.|year=2013|title=Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges river dolphins in a shallow, acoustically complex habitat|journal=PLOS ONE|volume=8|issue=4|page=e59284|doi=10.1371/journal.pone.0059284|pmid=23573197 |pmc=3616034 |bibcode=2013PLoSO...859284J |doi-access=free }}</ref> The Ganges species also has a protrusion near the [[frontal suture]], which distinguishes it from the Indus species.<ref name="Braulik_al20212"/> The teeth of South Asian river dolphins are curved and longer in the front, where they remain exposed when the jaws are closed.<ref name=Jefferson>{{cite book|last1=Jefferson|first1=Thomas A.|last2=Webber|first2=Marc A.|last3=Pitman|first3=Robert L.|year=2015|title=Marine Mammals of the World: A Comprehensive Guide to Their Identification|publisher=Academic Press|edition=2nd|pages=346–349|isbn=978-0-12-409542-7}}</ref> Indus dolphins have more teeth than Ganges dolphins, averaging 33.2 teeth in the upper jaw and the 32.9 in the lower jaw, as compared to 28.4 in the upper jaw and 29.4 in the lower.<ref name="Braulik_al20212"/>
-Living in murky waters, South Asian river dolphins are nearly blind, their tiny eyes having flattened [[cornea]]s and no [[Lens (anatomy)|lens]]. The [[retina]]—which connects to a reduced [[optic nerve]]—does not form images but instead merely discerns light. The animal relies on a [[sphincter]]-like muscle around the eye to control access to the retina and prevent [[light scattering]], similar to a [[Pinhole (optics)|pinhole]].<ref name=":0">{{Cite journal|last1=Herald|first1=Earl S.|last2=Brownell|first2=Robert L.|last3=Frye|first3=Fredric L.|last4=Morris|first4=Elkan J.|last5=Evans|first5=William E.|last6=Scott|first6=Alan B.|year=1969|title=Blind river dolphin: first side-swimming cetacean|journal=Science|volume=166|issue=3911|pages=1408–1410|jstor=1727285|doi=10.1126/science.166.3911.1408|pmid=5350341|bibcode=1969Sci...166.1408H|s2cid=5670792|url=https://digitalcommons.unl.edu/usdeptcommercepub/138}}</ref> The ears are adapted to hearing low frequencies, having a short, flattened cochlea with widely spaced spirals.<ref name=Viglino/>
+Living in murky waters, South Asian river dolphins are nearly blind, their tiny eyes having flattened [[cornea]]s and no [[Lens (anatomy)|lens]]. The [[retina]]—which connects to a reduced [[optic nerve]]—does not form images but instead merely discerns light. The animal relies on a [[sphincter]]-like muscle around the eye to control access to the retina and prevent [[light scattering]], similar to a [[Pinhole (optics)|pinhole]].<ref name=":0">{{Cite journal|last1=Herald|first1=Earl S.|last2=Brownell|first2=Robert L.|last3=Frye|first3=Fredric L.|last4=Morris|first4=Elkan J.|last5=Evans|first5=William E.|last6=Scott|first6=Alan B.|year=1969|title=Blind river dolphin: first side-swimming cetacean|journal=Science|volume=166|issue=3911|pages=1408–1410|jstor=1727285|doi=10.1126/science.166.3911.1408|pmid=5350341|bibcode=1969Sci...166.1408H|s2cid=5670792|url=https://digitalcommons.unl.edu/usdeptcommercepub/138|access-date=1 December 2019|archive-date=2 August 2023|archive-url=https://web.archive.org/web/20230802073543/https://digitalcommons.unl.edu/usdeptcommercepub/138/|url-status=live}}</ref> The ears are adapted to hearing low frequencies, having a short, flattened cochlea with widely spaced spirals.<ref name=Viglino/>
 ==Distribution and habitat==
@@ Line 78: / Line 78: @@
 The Indus river dolphin mainly lives in the Indus River of [[Pakistan]], with three subpopulations between the [[Chashma Barrage|Chashma]], [[Taunsa Barrage|Taunsa]], [[Guddu Barrage|Guddu]], and [[Sukkur Barrage|Sukkur]] [[Barrage (dam)|barrages]]. Two other populations exist south of Sukkur and in the [[Beas River]] of India.<ref name="Braulik_al20212"/><ref name="IWC">{{cite report|last1=Aisha|first1=H.|last2=Khan|first2=U.|date=April 2021|title=Abundance survey for Indus river dolphin, Final Report|publisher=IWC Small Cetacean Fund|doi=10.13140/RG.2.2.24280.83207}}</ref> In the 19th century, this species was reported to have occurred throughout the Indus River system, from the [[Indus River Delta]] north to [[Kalabagh]] just south of the Himalayas, including all the main tributaries.<ref name="Braulik_al20212"/> The Indus river dolphin is reported to have disappeared between the [[Jinnah Barrage|Jinnah]] and Chashma barrages after 2001.<ref name="IWC"/>
-South Asian river dolphins inhabit major river channels during the [[dry season]] and travel to smaller tributaries for the [[monsoon]]. They are most commonly found in [[stream pool]]s, [[meander]]s, and [[confluence]]s, and around [[river island]]s and [[shoal]]s, which produce relatively stable waters.<ref name="Sinha2014">{{Cite journal |last1=Sinha|first1=R. K.|last2=Kannan|first2=K. |year=2014 |title=Ganges river dolphin: an overview of biology, ecology, and conservation status in India |journal=Ambio |volume=43|issue=8|pages=1029–1046 |doi=10.1007/s13280-014-0534-7 |pmc=4235892 |pmid=24924188}}</ref> They can be found in pools over {{convert|30|m|abbr=on}} deep, but usually dwell in shallower water.<ref name=Jefferson/>
+South Asian river dolphins inhabit major river channels during the [[dry season]] and travel to smaller tributaries for the [[monsoon]]. They are most commonly found in [[stream pool]]s, [[meander]]s, and [[confluence]]s, and around [[river island]]s and [[shoal]]s, which produce relatively stable waters.<ref name="Sinha2014">{{Cite journal |last1=Sinha|first1=R. K.|last2=Kannan|first2=K. |year=2014 |title=Ganges river dolphin: an overview of biology, ecology, and conservation status in India |journal=Ambio |volume=43|issue=8|pages=1029–1046 |doi=10.1007/s13280-014-0534-7 |pmc=4235892 |pmid=24924188|bibcode=2014Ambio..43.1029S }}</ref> They can be found in pools over {{convert|30|m|abbr=on}} deep, but usually dwell in shallower water.<ref name=Jefferson/>
 ==Behaviour and life history==
 South Asian river dolphins appear to be active throughout the day. Living in flowing waters, they swim almost constantly with only brief periods of sleep, which add up to seven hours per day.<ref>{{cite journal|last=Pilleri|first=G.|year=1979|title=The blind Indus dolphin, ''Platanista indi''|journal=Endeavour|volume=3|issue=2|pages=48–56|doi=10.1016/0160-9327(79)90066-8}}</ref> They swim on their sides when in shallow water.<ref name=feeding/> River dolphins generally surface with the rostrum, head, and dorsal fin breaking the water and rarely [[Cetacean surfacing behaviour#Breaching and lunging|breach]] or raise the tail fluke, though surface activity can vary based on age, distance from shore and time of day. Diving may last as long as eight minutes among adults and subadults; dives of newborns and juveniles are not as long.<ref>{{cite journal|last1=Sinha|first1=R. K.|last2=Sinha|first2=S.|last3=Sharma|first3=G.|last4=Kedia|first4=D. K.|year=2010|title=Surfacing and diving behaviour of free-ranging Ganges river dolphin, ''Platanista gangetica gangetica''|journal=Current Science|volume=98|issue=2|pages=230–236|jstor=24111514}}</ref>
 [[File:B-Platanista-gangetica-in-natural-habitat.png|thumb|right|Indus river dolphins leaping|alt=Two dolphins leaping out of water]]
-River dolphins are typically seen alone or in groups of up to 10 individuals, though enough natural resources may attract up to 30 dolphins. Individuals do not appear to have strong social bonds, outside of mothers and calves.<ref name=Jefferson/> Living in shallow river environments with acoustic obstacles, these dolphins echolocate using repetitive clicks spaced 10 to 100 [[millisecond]]s apart.<ref name="Jensen22">{{cite journal |last1=Jensen |first1=F. H. |last2=Rocco |first2=A. |last3=Mansur |first3=R. M. |last4=Smith |first4=B. D. |last5=Janik |first5=V. M. |last6=Madsen |first6=P. T. |year=2013 |title=Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges river dolphins in a shallow, acoustically complex habitat |journal=PLOS ONE |volume=8 |issue=4 |page=e59284 |doi=10.1371/journal.pone.0059284 |pmc=3616034 |pmid=23573197 |bibcode=2013PLoSO...859284J |doi-access=free}}</ref><ref>{{cite book |last1=Sugimatsu |first1=H. |last2=Ura |first2=T. |last3=Mizuno |first3=K. |last4=Asada |first4=A. |title=2012 Oceans |chapter=Study of acoustic characteristics of Ganges river dolphin calf using ehcolocation clicks recorded during long-term in-situ observation |publisher=Oceans 2012 Conference |year=2012 |isbn=978-1-4673-0829-8 |pages=1–7 |doi=10.1109/OCEANS.2012.6405029 |s2cid=22758375}}</ref> Their clicks are about one [[octave]] below those of oceanic toothed whales of comparable size, meaning that they provide less information about the location of an object, but the dolphins' maxillary crests likely compensate by providing greater directional sensitivity.<ref name="Jensen"/> Vocalizations used for communication include bursts and twitterings.<ref>{{cite journal|last1=Mizue|first1=K.|last2=Masaharu|first2=N.|last3=Akira|first3=T.|year=1971|title=The underwater sounds of Ganges River dolphin (Platanista gangetica)|journal= The Scientific Reports of the Whales Research Institute|volume=23|pages=123–128}}</ref>
+River dolphins are typically seen alone or in groups of up to 10 individuals, though enough natural resources may attract up to 30 dolphins. Individuals do not appear to have strong social bonds, outside of mothers and calves.<ref name=Jefferson/> Living in shallow river environments with acoustic obstacles, these dolphins echolocate using repetitive clicks spaced 10 to 100 [[millisecond]]s apart.<ref name="Jensen22">{{cite journal |last1=Jensen |first1=F. H. |last2=Rocco |first2=A. |last3=Mansur |first3=R. M. |last4=Smith |first4=B. D. |last5=Janik |first5=V. M. |last6=Madsen |first6=P. T. |year=2013 |title=Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges river dolphins in a shallow, acoustically complex habitat |journal=PLOS ONE |volume=8 |issue=4 |page=e59284 |doi=10.1371/journal.pone.0059284 |pmc=3616034 |pmid=23573197 |bibcode=2013PLoSO...859284J |doi-access=free}}</ref><ref>{{cite book |last1=Sugimatsu |first1=H. |last2=Ura |first2=T. |last3=Mizuno |first3=K. |last4=Asada |first4=A. |title=2012 Oceans |chapter=Study of acoustic characteristics of Ganges river dolphin calf using ehcolocation clicks recorded during long-term in-situ observation |publisher=Oceans 2012 Conference |year=2012 |isbn=978-1-4673-0829-8 |pages=1–7 |doi=10.1109/OCEANS.2012.6405029 |s2cid=22758375}}</ref> Their clicks are about one [[octave]] below those of oceanic toothed whales of comparable size, meaning that they provide less information about the location of an object, but the dolphins' maxillary crests likely compensate by providing greater directional sensitivity.<ref name="Jensen"/> Vocalisations used for communication include bursts and twitterings.<ref>{{cite journal|last1=Mizue|first1=K.|last2=Masaharu|first2=N.|last3=Akira|first3=T.|year=1971|title=The underwater sounds of Ganges River dolphin (Platanista gangetica)|journal= The Scientific Reports of the Whales Research Institute|volume=23|pages=123–128}}</ref>
-River dolphins feed mainly on fish and shrimp. In one study, around 46% of prey items were found to be [[Benthic zone|bottom-dwelling]] species, while 31% were near the surface, and 23% occupied the middle of the column. The most frequently taken prey are [[Bagridae|bagrid catfish]], [[Barb (fish)|barbs]], [[Ambassidae|glass perches]], [[Mastacembelidae|spiny eels]], [[Gobiidae|gobies]], and [[Palaemonidae|prawns]]. When hunting at the surface, dolphins listen for the movements of schooling fish which are then herded with spins, side-swimming, and [[Cetacean surfacing behavior #Lobtailing and slapping|lobtailing]]. Echolocation signals are not frequently used at the surface, since many fish at this level can hear ultrasound. At the mid-surface level, the dolphins use more echolocation clicks to find prey hidden in clutter and vegetation as far as {{convert|20|m|abbr=on}} away. They flush out bottom-dwelling prey by digging around.<ref name=feeding>{{cite journal|last1=Kelhar|first1=N.|last2=Dey|first2=S.|last3=Deshpande|first3=K.|last4=Choudhary|first4=S. K.|last5=Dey|first5=S.|last6=Morisaka|first6=T.|year=2018|title=Foraging and feeding ecology of ''Platanista'': an integrative review|journal=Mammal Review|volume=48|issue=3|pages=194–208|doi=10.1111/mam.12124|s2cid=89753459}}</ref>
+River dolphins feed mainly on fish and shrimp. In one [[meta study]], around 46% of prey items were found to be [[Benthic zone|bottom-dwelling]] species, while 31% were near the surface, and 23% occupied the middle of the column. The most frequently taken prey are [[Bagridae|bagrid catfish]], [[Barb (fish)|barbs]], [[Ambassidae|glass perches]], [[Mastacembelidae|spiny eels]], [[Gobiidae|gobies]], and [[Palaemonidae|prawns]]. When hunting at the surface, dolphins listen for the movements of schooling fish which are then herded with spins, side-swimming, and [[Cetacean surfacing behavior #Lobtailing and slapping|lobtailing]]. Echolocation signals are not frequently used at the surface, since many fish at this level can hear ultrasound. At the mid-surface level, the dolphins use more echolocation clicks to find prey hidden in clutter and vegetation as far as {{convert|20|m|abbr=on}} away. They flush out bottom-dwelling prey by digging around.<ref name=feeding>{{cite journal|last1=Kelhar|first1=N.|last2=Dey|first2=S.|last3=Deshpande|first3=K.|last4=Choudhary|first4=S. K.|last5=Dey|first5=S.|last6=Morisaka|first6=T.|year=2018|title=Foraging and feeding ecology of ''Platanista'': an integrative review|journal=Mammal Review|volume=48|issue=3|pages=194–208|doi=10.1111/mam.12124|s2cid=89753459}}</ref>
-Little is known about reproduction in these river dolphins.<ref name=Jefferson/> Courtship and mating behaviour for the Ganges species has been documented from March to May, when the water level is lower, and involves multiple males chasing one female and ends with one of the males earning the right to mate.<ref name=supplemantary>{{Cite journal |last1=Sinha|first1=R. K.|last2=Kannan|first2=K. |year=2014 |title=Ganges river dolphin: an overview of biology, ecology, and conservation status in India (Supplementary material 1) |journal=Ambio |volume=43|issue=8|pages=1029–1046 |doi=10.1007/s13280-014-0534-7 |pmc=4235892 |pmid=24924188}}</ref> Calves are born around a year later.<ref name=Perrin2015>{{cite book|editor-first1=William F.|editor-last1=Perrin|editor-first2=Bernd |editor-last2= Wursig|editor-first3=J. G. M. |editor-last3=Thewissen|title=Encyclopedia of Marine Mammals|publisher=Academic Press|isbn= 978-0-12-804327-1|year=2015|last1=Smith|first1=B. D. |last2=Braulik|first2=G. T.|contribution=Susu and Bhulan|pages=1135–1139}}</ref> Births in the Ganges river dolphin appear to be most frequent between December and January and between March and May. For Indus river dolphins, newborns are most commonly seen between April and May.<ref name=Jefferson/> Indus river dolphins calves are around {{convert|70|cm|abbr=on}} long at birth and may nurse for up to a year. They eat their first solid food within a couple months. South Asian river dolphins reach sexual maturity at around ten years, though males may not reach their adult size until 20 years.<ref>{{cite journal|last=Kasuya|first=T.|year=1972|title=Some information on the growth of the Ganges dolphin with a comment on the Indus dolphin|journal= The Scientific Reports of the Whales Research Institute|volume=24|pages=87–108}}</ref> Growth layers in the teeth suggest South Asian river dolphins can live up to 30 years.<ref>{{cite journal|last1=Lockyer|first1=C. H.|last2=Braulik|first2=G. T.|year=2014|title=An evaluation of age estimation using teeth from South Asian River dolphins (Platanistidae)|journal=NAMMCO Scientific Publications|volume=10|doi=10.7557/3.3268}}</ref>
+Little is known about reproduction in these river dolphins.<ref name=Jefferson/> Courtship and mating behaviour for the Ganges species has been documented from March to May, when the water level is lower, and involves multiple males chasing one female and ends with one of the males earning the right to mate.<ref name=supplemantary>{{Cite journal |last1=Sinha|first1=R. K.|last2=Kannan|first2=K. |year=2014 |title=Ganges river dolphin: an overview of biology, ecology, and conservation status in India (Supplementary material 1) |journal=Ambio |volume=43|issue=8|pages=1029–1046 |doi=10.1007/s13280-014-0534-7 |pmc=4235892 |pmid=24924188|bibcode=2014Ambio..43.1029S }}</ref> Calves are born around a year later.<ref name=Perrin2015>{{cite book|editor-first1=William F.|editor-last1=Perrin|editor-first2=Bernd |editor-last2= Wursig|editor-first3=J. G. M. |editor-last3=Thewissen|title=Encyclopedia of Marine Mammals|publisher=Academic Press|isbn= 978-0-12-804327-1|year=2015|last1=Smith|first1=B. D. |last2=Braulik|first2=G. T.|contribution=Susu and Bhulan|pages=1135–1139}}</ref> Births in the Ganges river dolphin appear to be most frequent between December and January and between March and May. For Indus river dolphins, newborns are most commonly seen between April and May.<ref name=Jefferson/> Indus river dolphins calves are around {{convert|70|cm|abbr=on}} long at birth and may nurse for up to a year. They eat their first solid food within a couple months. South Asian river dolphins reach sexual maturity at around ten years, though males may not reach their adult size until 20 years.<ref>{{cite journal|last=Kasuya|first=T.|year=1972|title=Some information on the growth of the Ganges dolphin with a comment on the Indus dolphin|journal= The Scientific Reports of the Whales Research Institute|volume=24|pages=87–108}}</ref> Growth layers in the teeth suggest South Asian river dolphins can live up to 30 years.<ref>{{cite journal|last1=Lockyer|first1=C. H.|last2=Braulik|first2=G. T.|year=2014|title=An evaluation of age estimation using teeth from South Asian River dolphins (Platanistidae)|journal=NAMMCO Scientific Publications|volume=10|doi=10.7557/3.3268|doi-access=free|hdl=10023/20641|hdl-access=free}}</ref>
 ==Conservation==
 [[File:Ganges-river-dolphins.jpg|thumb|right|Man holding Ganges river dolphin in [[Bhagalpur]]|alt=Man standing in water while holding dolphin]]
-As of 2022, the [[IUCN Red List]] of mammals lists both South Asian river dolphins as [[Endangered species|endangered]].<ref name="iucn status 2022">{{cite iucn |author1=Kelkar, N.|author2=Smith, B. D.|author3=Alom, M. Z.|author4=Dey, S.|author5=Paudel, S.|author6=Braulik, G. T.|date=2022 |title=''Platanista gangetica'' |volume=2022 |page=e.T41756A50383346 |doi=10.2305/IUCN.UK.2022-1.RLTS.T41756A50383346.en |access-date=17 October 2022}}</ref><ref name=IUCN>{{cite iucn |title=''Platanista minor''  |author=Braulik, G. T.|author2=Khan, U. |author3=Malik, M. |author4=Aisha, H.|year=2022 |page= e.T41757A50383490 |doi=10.2305/IUCN.UK.2022-1.RLTS.T41757A50383490.en|access-date=14 October 2022}}</ref> Two assessments in 2014 and 2015 estimated populations of 3,500 for the Ganges river dolphin and 1,500 for the Indus river dolphin.<ref name="Sinha2014"/><ref name="Braulik2015">{{Cite journal|year=2015|title=Review of status, threats, and conservation management options for the endangered Indus River blind dolphin|url=https://www.sciencedirect.com/science/article/abs/pii/S0006320715300999|journal=Biological Conservation|language=en|volume=192|pages=30–41|doi=10.1016/j.biocon.2015.09.008|issn=0006-3207|last1=Braulik|first1=Gill T.|last2=Noureen|first2=Uzma|last3=Arshad|first3=Masood|last4=Reeves|first4=Randall R.}}</ref> The Ganges species appears to be decreasing, while the Indus species may be increasing.<ref name="iucn status 2022"/><ref name=IUCN/> The habitat of these river dolphins intersects with some of the most densely populated areas, leading to intense competition for water and resources.<ref name="Sinha2014"/><ref name="Braulik2015"/><ref name=Paudel2020/>
+As of 2022, the [[IUCN Red List]] of mammals lists both South Asian river dolphins as [[Endangered species|endangered]].<ref name="iucn status 2022">{{cite iucn |author1=Kelkar, N.|author2=Smith, B. D.|author3=Alom, M. Z.|author4=Dey, S.|author5=Paudel, S.|author6=Braulik, G. T.|date=2022 |title=''Platanista gangetica'' |volume=2022 |page=e.T41756A50383346 |doi=10.2305/IUCN.UK.2022-1.RLTS.T41756A50383346.en |access-date=17 October 2022}}</ref><ref name=IUCN>{{cite iucn |title=''Platanista minor''  |author=Braulik, G. T.|author2=Khan, U. |author3=Malik, M. |author4=Aisha, H.|year=2022 |page= e.T41757A50383490 |doi=10.2305/IUCN.UK.2022-1.RLTS.T41757A50383490.en|access-date=14 October 2022}}</ref> Two assessments in 2014 and 2015 estimated populations of 3,500 for the Ganges river dolphin and 1,500 for the Indus river dolphin.<ref name="Sinha2014"/><ref name="Braulik2015">{{Cite journal|year=2015|title=Review of status, threats, and conservation management options for the endangered Indus River blind dolphin|url=https://www.sciencedirect.com/science/article/abs/pii/S0006320715300999|journal=Biological Conservation|language=en|volume=192|pages=30–41|doi=10.1016/j.biocon.2015.09.008|issn=0006-3207|last1=Braulik|first1=Gill T.|last2=Noureen|first2=Uzma|last3=Arshad|first3=Masood|last4=Reeves|first4=Randall R.|bibcode=2015BCons.192...30B |access-date=27 August 2021|archive-date=22 September 2022|archive-url=https://web.archive.org/web/20220922070257/https://www.sciencedirect.com/science/article/abs/pii/S0006320715300999|url-status=live}}</ref> The Ganges species appears to be decreasing, while the Indus species may be increasing.<ref name="iucn status 2022"/><ref name=IUCN/> The habitat of these river dolphins intersects with some of the most densely populated areas, leading to intense competition for water and resources.<ref name="Sinha2014"/><ref name="Braulik2015"/><ref name=Paudel2020/>
 The creation of dams and barrages in the Indus River system have heavily [[habitat fragmentation|fragmented]] the range of the Indus river dolphin, leading to a population decline of 80% since the 19th century.<ref name="Braulik2015"/> Around 50 such structures have been built in the historical range of the Ganges species.<ref name="Sinha2014"/> Fragmentation of populations makes these dolphins more vulnerable to inbreeding.<ref name=Paudel2020/> The heavy extraction of water in these dense populations also puts the dolphins at risk.<ref name="Sinha2014"/>
-River dolphins [[Bioaccumulation|accumulate]] high amounts of [[persistent organic pollutant]]s, [[pesticides]], and [[heavy metals]] in their system due to being at the top of their riverine [[food web]].<ref name="Sinha2014"/><ref name="Braulik2015"/> Hence, they are seen as [[bioindicator]]s for the health of river systems.<ref name="Sinha2014"/> Fisherman compete with these animals for fish of certain sizes.<ref name=Paudel2020>{{cite journal|last1=Paudel|first1=S.|last2=Koprowski|first2=J. L.|year=2020|title=Factors affecting the persistence of endangered Ganges River dolphins (''Platanista gangetica gangetica'')|journal=Ecology and Evolution|volume=10|issue=6|pages=3138–3148|doi=10.1002/ece3.6102|pmid=32211183 |pmc=7083702 }}</ref> Dolphins captured in fishing nets are usually [[Bycatch|accidental]], but dolphin oil is sought after as a fish lure, and thus fishermen may be motivated to kill caught dolphins.<ref name="Sinha2014"/> Being nearly blind and relying on echolocation for navigation, river dolphins are also negatively affected by [[noise pollution]] from boats.<ref>{{cite journal|last1=Dey|first1=M.|last2=Krishnaswamy|first2=J.|last3=Morisaka|first3=T.|last4=Kelkar|first4=N.|year=2019|title=Interacting effects of vessel noise and shallow river depth elevate metabolic stress in Ganges river dolphins|journal=Scientific Reports|volume=9|issue=15426|page=15426 |doi=10.1038/s41598-019-51664-1|pmid=31659202|pmc=6817857|bibcode=2019NatSR...915426D |s2cid=204918073}}</ref>
+River dolphins [[Bioaccumulation|accumulate]] high amounts of [[persistent organic pollutant]]s, [[pesticides]], and [[heavy metals]] in their system due to being at the top of their riverine [[food web]].<ref name="Sinha2014"/><ref name="Braulik2015"/> Hence, they are seen as [[bioindicator]]s for the health of river systems.<ref name="Sinha2014"/> Fishermen compete with these animals for fish of certain sizes.<ref name=Paudel2020>{{cite journal|last1=Paudel|first1=S.|last2=Koprowski|first2=J. L.|year=2020|title=Factors affecting the persistence of endangered Ganges River dolphins (''Platanista gangetica gangetica'')|journal=Ecology and Evolution|volume=10|issue=6|pages=3138–3148|doi=10.1002/ece3.6102|pmid=32211183 |pmc=7083702 |bibcode=2020EcoEv..10.3138P }}</ref> Dolphins captured in fishing nets are usually [[Bycatch|accidental]], but dolphin oil is sought after as a fish lure, and thus fishermen may be motivated to kill caught dolphins.<ref name="Sinha2014"/> Being nearly blind and relying on echolocation for navigation, river dolphins are also negatively affected by [[noise pollution]] from boats.<ref>{{cite journal|last1=Dey|first1=M.|last2=Krishnaswamy|first2=J.|last3=Morisaka|first3=T.|last4=Kelkar|first4=N.|year=2019|title=Interacting effects of vessel noise and shallow river depth elevate metabolic stress in Ganges river dolphins|journal=Scientific Reports|volume=9|issue=15426|page=15426 |doi=10.1038/s41598-019-51664-1|pmid=31659202|pmc=6817857|bibcode=2019NatSR...915426D |s2cid=204918073}}</ref>
-South Asian river dolphins are protected by law in all the states they inhabit. They can be found in numerous protected areas,<ref name="iucn status 2022"/><ref name=IUCN/> including ones established specifically for them, such as the [[Indus Dolphin Reserve]] in Pakistan and the [[Vikramshila Gangetic Dolphin Sanctuary]] in India.<ref name="Sinha2014"/><ref name="Braulik2015"/> International trade is prohibited by the listing of the South Asian river dolphins on Appendix I of the [[Convention on International Trade in Endangered Species]].<ref name="Appendices {{!}} CITES">{{Cite web|title=Appendix I|url=https://cites.org/eng/app/appendices.php|access-date=2023-01-06|date=2022-06-22|work=Convention on International Trade in Endangered Species of Wild Fauna and Flora}}</ref> The Ganges and Indus river dolphins are considered to be the [[List of national animals|national aquatic animals]] of India and Pakistan respectively.<ref name="National Portal of India">{{cite web|url=http://knowindia.gov.in/knowindia/national_symbols.php?id=8|title=National Aquatic Animal – National Symbols – Know India: National Portal of India|publisher=National Portal of India|access-date=23 March 2012|url-status=dead|archive-url=https://web.archive.org/web/20130122081831/http://www.knowindia.gov.in/knowindia/national_symbols.php?id=8|archive-date=22 January 2013}}</ref><ref name="National Symbols of Pakistan">{{cite web|url=http://www.pakistan.gov.pk/national_symbols.html|title=National Symbols of Pakistan|publisher=Government of Pakistan|access-date=23 October 2016|url-status=dead|archive-url=https://web.archive.org/web/20161128073024/http://www.pakistan.gov.pk/national_symbols.html|archive-date=28 November 2016}}</ref>
+South Asian river dolphins are protected by law in all the states they inhabit. They can be found in numerous protected areas,<ref name="iucn status 2022"/><ref name=IUCN/> including ones established specifically for them, such as the [[Indus Dolphin Reserve]] in Pakistan and the [[Vikramshila Gangetic Dolphin Sanctuary]] in India.<ref name="Sinha2014"/><ref name="Braulik2015"/> International trade is prohibited by the listing of the South Asian river dolphins on Appendix I of the [[Convention on International Trade in Endangered Species]].<ref name="Appendices {{!}} CITES">{{Cite web|title=Appendix I|url=https://cites.org/eng/app/appendices.php|access-date=2023-01-06|date=2022-06-22|work=Convention on International Trade in Endangered Species of Wild Fauna and Flora|archive-date=5 October 2011|archive-url=https://web.archive.org/web/20111005165017/http://www.cites.org/eng/app/appendices.shtml|url-status=live}}</ref> The Ganges and Indus river dolphins are considered to be the [[List of national animals|national aquatic animals]] of India and Pakistan respectively.<ref name="National Portal of India">{{cite web|url=http://knowindia.gov.in/knowindia/national_symbols.php?id=8|title=National Aquatic Animal – National Symbols – Know India: National Portal of India|publisher=National Portal of India|access-date=23 March 2012|url-status=dead|archive-url=https://web.archive.org/web/20130122081831/http://www.knowindia.gov.in/knowindia/national_symbols.php?id=8|archive-date=22 January 2013}}</ref><ref name="National Symbols of Pakistan">{{cite web|url=http://www.pakistan.gov.pk/national_symbols.html|title=National Symbols of Pakistan|publisher=Government of Pakistan|access-date=23 October 2016|url-status=dead|archive-url=https://web.archive.org/web/20161128073024/http://www.pakistan.gov.pk/national_symbols.html|archive-date=28 November 2016}}</ref>
 == See also ==
@@ Line 119: / Line 119: @@
 {{Authority Control}}
+[[Category:South Asian river dolphin| ]]
 [[Category:Apex predators]]
 [[Category:Cetacean genera]]
 [[Category:Mammals of South Asia]]
-[[Category:River dolphins]]
+[[Category:Platanistidae]]
 [[Category:Taxa named by Johann Georg Wagler]]
+[[Category:Extant Quaternary first appearances]]