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{{short description|Thick layer of animal body fat}} |
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{{Other uses|Blubber (disambiguation)}} |
{{Other uses|Blubber (disambiguation)}} |
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{{Use dmy dates|date= |
{{Use dmy dates|date=December 2020}} |
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[[File:Whale blubber.jpg|thumb|Whale blubber]] |
[[File:Whale blubber.jpg|300px|thumb|Whale blubber]] |
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'''Blubber''' is a thick layer of [[vascular]]ized [[adipose tissue]] under the skin of all [[cetacea]]ns, [[pinniped]]s and [[sirenia]]ns. |
'''Blubber''' is a thick layer of [[Blood vessel|vascular]]ized [[adipose tissue]] under the skin of all [[cetacea]]ns, [[pinniped]]s, [[penguin]]s, and [[sirenia]]ns. It was present in many [[marine reptile]]s, such as [[Ichthyosauria|ichthyosaurs]] and [[plesiosaur]]s.<ref>{{Cite web |date=2018-12-05 |title=Incredible Jurassic ichthyosaur fossil still has skin and blubber |url=https://www.nationalgeographic.com/science/article/incredible-jurassic-ichthyosaur-fossil-preserves-skin-blubber |access-date=2024-01-12 |website=Science |language=en}}</ref> |
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==Description== |
==Description== |
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[[Lipid]]-rich, [[collagen]] fiber-laced blubber comprises the [[Subcutaneous tissue|hypodermis]]<ref>{{cite journal |doi=10.1002/jmor.10154 |title=Blubber development in bottlenose dolphins (Tursiops truncatus) |year=2004 |last1=Struntz |first1=D.J. |last2=McLellan |first2=W.A. |last3=Dillaman |first3=R.M. |last4=Blum |first4=J.E. |last5=Kucklick |first5=J.R. |last6=Pabst |first6=D.A. |journal=Journal of Morphology |volume=259 |pages=7–20 |pmid=14666521 |issue=1}}</ref> and covers the whole body, except for parts of the appendages. It is strongly attached to the musculature and skeleton by highly organized, fan-shaped networks of [[tendon]]s and [[ligament]]s, can comprise up to 50 |
[[Lipid]]-rich, [[collagen]] fiber-laced blubber comprises the [[Subcutaneous tissue|hypodermis]]<ref>{{cite journal |doi=10.1002/jmor.10154 |title=Blubber development in bottlenose dolphins (Tursiops truncatus) |year=2004 |last1=Struntz |first1=D.J. |last2=McLellan |first2=W.A. |last3=Dillaman |first3=R.M. |last4=Blum |first4=J.E. |last5=Kucklick |first5=J.R. |last6=Pabst |first6=D.A. |journal=Journal of Morphology |volume=259 |pages=7–20 |pmid=14666521 |issue=1|s2cid=24897702 }}</ref> and covers the whole body, except for parts of the appendages. It is strongly attached to the musculature and skeleton by highly organized, fan-shaped networks of [[tendon]]s and [[ligament]]s, can comprise up to 50 per cent of the body mass of some [[marine mammal]]s during some points in their lives, and can range from {{cvt|2|in|cm|order=flip|0}} thick in dolphins and smaller whales, to more than {{cvt|12|in|cm|order=flip}} thick in some bigger whales, such as [[Right whale|right]] and [[bowhead whale]]s. However, this is not indicative of larger whales' ability to retain heat better, as the thickness of a whale's blubber does not significantly affect heat loss. More indicative of a whale's ability to retain heat is the water and lipid concentration in blubber, as water reduces heat-retaining capacities, and lipid increases them.<ref>{{cite journal |doi=10.1016/0306-4565(95)00034-8 |title=Thermal conductivity of minke whale blubber |year=1996 |last1=Kvadsheim |first1=P.H. |last2=Folkow |first2=L.P. |last3=Blix |first3=A.S. |journal=Journal of Thermal Biology |volume=21 |issue=2 |pages=123–8}}</ref> |
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==Function== |
==Function== |
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Blubber is the primary fat storage on some [[mammal]]s, specifically those that live in water. It is particularly important for species that feed and breed in different parts of the ocean. During these periods, the animals [[metabolism|metabolize]] fat. Blubber may save energy for marine mammals, such as dolphins, in that it adds buoyancy while [[Whale#Locomotion|swimming]].<ref>{{cite web |url=http://www.sciencenetlinks.net/sci_update.php?DocID=10 |archive-url=https://web.archive.org/web/20130921054320/http://www.sciencenetlinks.net/sci_update.php?DocID=10 |url-status=dead |archive-date=2013-09-21 |website=Science Update |title=Bouncy Blubber |publisher=AAAS }}</ref> |
Blubber is the primary fat storage on some [[mammal]]s, specifically those that live in water. It is particularly important for species that feed and breed in different parts of the ocean. During these periods, the animals [[metabolism|metabolize]] fat. Blubber may save energy for marine mammals, such as dolphins, in that it adds [[buoyancy]] while [[Whale#Locomotion|swimming]].<ref>{{cite web |url=http://www.sciencenetlinks.net/sci_update.php?DocID=10 |archive-url=https://web.archive.org/web/20130921054320/http://www.sciencenetlinks.net/sci_update.php?DocID=10 |url-status=dead |archive-date=2013-09-21 |website=Science Update |title=Bouncy Blubber |publisher=AAAS }}</ref> |
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Blubber differs from other forms of [[adipose tissue]] in its extra thickness, which provides an efficient thermal [[Thermal insulation|insulator]], making blubber essential for [[thermoregulation]]. Blubber is more vascularized—rich in [[blood vessel]]s—than other adipose tissue. |
Blubber differs from other forms of [[adipose tissue]] in its extra thickness, which provides an efficient thermal [[Thermal insulation|insulator]], making blubber essential for [[thermoregulation]]. Blubber is more vascularized—rich in [[blood vessel]]s—than other adipose tissue. |
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Blubber has advantages over fur (as in [[sea otter]]s) in that, though fur retains heat by holding pockets of air, the air expels under pressure (i.e., when the animal dives). Blubber, however, does not compress under pressure. It is effective enough that some whales can dwell in temperatures as low as {{convert|40|F}}.<ref>{{cite web | url= https://www.pbs.org/oceanrealm/intheschool/school5.html | title= Secrets of the Ocean Realm | url-status= live | |
Blubber has advantages over fur (as in [[sea otter]]s) in that, though fur retains heat by holding pockets of air, the air expels under pressure (i.e., when the animal dives). Blubber, however, does not compress under pressure. It is effective enough that some whales can dwell in temperatures as low as {{convert|40|F|order=flip}}.<ref>{{cite web | url= https://www.pbs.org/oceanrealm/intheschool/school5.html | title= Secrets of the Ocean Realm | url-status= live | archive-url= https://web.archive.org/web/20170504042247/http://www.pbs.org/oceanrealm/intheschool/school5.html | archive-date= 4 May 2017}}</ref> While diving in cold water, blood vessels covering the blubber constrict and decrease blood flow, thus increasing blubber's efficiency as an insulator.<ref>{{cite book |author= Galbraith, Don|display-authors=et al |title=Biology 11 |location= Canada |publisher= McGraw-Hill Ryerson |page= 12}}</ref> |
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Blubber aids |
Blubber aids buoyancy and streamlines the body, because the organized, complex collagenous network supports the noncircular cross sections characteristic of cetaceans. The buoyancy of blubber could be problematic for bottom-feeding marine mammals such as [[sirenian]]s and the extinct [[Thalassocnus|marine sloths]], both of which do or probably did have limited amounts of it for that reason.<ref name="Horgan2014">{{cite journal|last1= Horgan|first1= P.|last2= Booth|first2= D.|last3= Nichols|first3= C.|last4= Lanyon|first4=J. M.|title= Insulative capacity of the integument of the dugong (''Dugong dugon''): thermal conductivity, conductance and resistance measured by in vitro heat flux|journal= Marine Biology|volume= 161|issue= 6|year= 2014|pages= 1395–1407|doi= 10.1007/s00227-014-2428-4|s2cid= 83824482}}</ref><ref name="Amson2015">{{Cite journal|last1= Amson|first1= E.|last2= Argot|first2= C.|last3= McDonald|first3=H. G.|last4=de Muizon|first4= C.|year= 2015|title= Osteology and functional morphology of the axial postcranium of the marine sloth ''Thalassocnus'' (Mammalia, Tardigrada) with paleobiological implications|journal= Journal of Mammalian Evolution|volume= 22|issue= 4|pages= 473–518|doi= 10.1007/s10914-014-9280-7|s2cid= 16700349}}</ref> |
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Research<ref>{{cite journal |doi= 10.1242/jeb.01559 |title= The ontogenetic changes in the thermal properties of blubber from Atlantic bottlenose dolphin Tursiops truncatus |year=2005 |last1=Dunkin |first1=R. C. |journal=Journal of Experimental Biology |volume=208 |issue=8 |pages=1469–80 |pmid=15802671}}</ref> into the [[thermal conductivity]] of the common [[bottlenose dolphin]]'s blubber reveals its thickness and lipid content vary greatly amongst individuals and across life history categories. Blubber from emaciated dolphins is a poorer insulator than that from nonpregnant adults, which in turn have a higher heat conductivity than blubber from pregnant females and adolescents. |
Research<ref>{{cite journal |doi= 10.1242/jeb.01559 |title= The ontogenetic changes in the thermal properties of blubber from Atlantic bottlenose dolphin Tursiops truncatus |year=2005 |last1=Dunkin |first1=R. C. |journal=Journal of Experimental Biology |volume=208 |issue=8 |pages=1469–80 |pmid=15802671|doi-access=free }}</ref> into the [[thermal conductivity]] of the common [[bottlenose dolphin]]'s blubber reveals its thickness and lipid content vary greatly amongst individuals and across life history categories. Blubber from emaciated dolphins is a poorer insulator than that from nonpregnant adults, which in turn have a higher heat conductivity than blubber from pregnant females and adolescents. |
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==Human influences== |
==Human influences== |
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[[File:Whaling Trypot (Blubber Pot), Simon's Town SA.jpg|thumb|[[Try pot]] or ''Blubber Pot'' seen in [[Simon's Town]] in [[South Africa]]]] |
[[File:Whaling Trypot (Blubber Pot), Simon's Town SA.jpg|thumb|[[Try pot]] or ''Blubber Pot'' seen in [[Simon's Town]] in [[South Africa]]]] |
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===Uses=== |
===Uses=== |
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''Uqhuq''<ref name=translate>{{cite book|last=Ohokak|first=G.|author2=M. Kadlun|author3=B. Harnum|title=Inuinnaqtun-English Dictionary|publisher=Kitikmeot Heritage Society|url=http://www.nald.ca/library/learning/nac/nac_dictionary/nac_dictionary.pdf| |
''Uqhuq'',<ref name=translate>{{cite book|last=Ohokak|first=G.|author2=M. Kadlun|author3=B. Harnum|title=Inuinnaqtun-English Dictionary|publisher=Kitikmeot Heritage Society|url=http://www.nald.ca/library/learning/nac/nac_dictionary/nac_dictionary.pdf|access-date=6 March 2013|url-status=dead|archive-url=https://web.archive.org/web/20120904191006/http://www.nald.ca/library/learning/nac/nac_dictionary/nac_dictionary.pdf|archive-date=4 September 2012}}</ref> or ''uqsuq'',<ref>{{cite news |url=http://www.livingdictionary.com/term/viewTerm.jsp?term=49165130231 |work=Asuilaak Living Dictionary |title=Blubber |date=November 2016 }}{{dead link|date=July 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> ("blubber" in the [[Inuktitut]] language) is an important part of the [[Inuit diet|traditional diets]] of the [[Inuit]] and of other northern peoples, because of its high energy value and availability. Whale blubber, which tastes like [[arrowroot]] biscuits, has similar properties.<ref> |
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{{cite book |
{{cite book |
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|last1=Stefansson |
|last1=Stefansson |
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|title=Missionärer bland Eskimåer |
|title=Missionärer bland Eskimåer |
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|trans-title=Missionaries Among the Eskimos |
|trans-title=Missionaries Among the Eskimos |
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|language= |
|language=sv |
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|publisher=Himmelriket på Jorden Publikationer |
|publisher=Himmelriket på Jorden Publikationer |
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|location=Göteborg |
|location=Göteborg |
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| Line 37: | Line 38: | ||
|page=138 |
|page=138 |
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}} |
}} |
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</ref> <!--It has been suggested that because the fats of the Inuit's wild-caught game are largely [[monounsaturated fat|monounsaturated]] and rich in [[omega-3 fatty acid]]s, the diet does not pose the same health risks as a typical Western high-fat diet.<ref name="paradox">{{cite web|url=http://discovermagazine.com/2004/oct/inuit-paradox/article_view?b_start:int=1&-C=|title=The Inuit Paradox|last=Gadsby|first=Patricia|date=October 1, 2004|work=Discover Magazine|pages=1–4| |
</ref> <!--It has been suggested that because the fats of the Inuit's wild-caught game are largely [[monounsaturated fat|monounsaturated]] and rich in [[omega-3 fatty acid]]s, the diet does not pose the same health risks as a typical Western high-fat diet.<ref name="paradox">{{cite web|url=http://discovermagazine.com/2004/oct/inuit-paradox/article_view?b_start:int=1&-C=|title=The Inuit Paradox|last=Gadsby|first=Patricia|date=October 1, 2004|work=Discover Magazine|pages=1–4|access-date=24 December 2009}}</ref> However, actual evidence has shown that Inuit have a similar prevalence of [[coronary artery disease]] as non-Inuit populations and they have excessive mortality due to [[stroke|cerebrovascular strokes]], with twice the risk to that of the North American population.<ref name="FodorHelis2014">{{cite journal|last1=Fodor|first1=George J.|last2=Helis|first2=Eftyhia|last3=Yazdekhasti|first3=Narges|last4=Vohnout|first4=Branislav|title="Fishing" for the origins of the "Eskimos and heart disease" story. Facts or wishful thinking? A review|journal=Canadian Journal of Cardiology|year=2014|issn=0828-282X|doi=10.1016/j.cjca.2014.04.007|doi=10.1016/j.cjca.2014.04.007|volume=30|pages=864–868|pmid=25064579}}</ref><ref name="Slate082014">{{cite news |last=Preston |first=Elizabeth |url=http://www.slate.com/articles/health_and_science/medical_examiner/2014/08/does_fish_oil_prevent_heart_disease_original_danish_eskimo_diet_study_was.html |title=The Fishy Origins of the Fish Oil Craze |work=Slate |publisher=The Slate Group |date=2014-08-01 |access-date=2014-08-05 |quote=In the 1970s, a pair of Danish researchers ventured north of the Arctic Circle and into medical lore. Studying a scattered Inuit population, they concluded that eating plenty of fish and other marine animals protected this group from heart disease. The researchers would eventually suggest that everyone else's hearts and arteries might also benefit from the "Eskimo diet," promoting a health food trend that continues to this day. The only trouble is, the two Danes never proved that the Inuit had low rates of heart disease. They never tested it at all. But today the market for fish oil pills is booming, even as scientists conduct trial after trial to hunt for a link to heart health that has never quite solidified. }}</ref> Indeed, the cardiovascular risk of this diet is so severe that the addition of a more [[Western pattern diet|standard American diet]] has reduced the incidence of mortality in the Inuit population.<ref>{{Cite journal|title = Low incidence of cardiovascular disease among the Inuit--what is the evidence?|journal = Atherosclerosis|date = 2003-02-01|issn = 0021-9150|pmid = 12535749|pages = 351–357|volume = 166|issue = 2|first = Peter|last = Bjerregaard|first2 = T. Kue|last2 = Young|first3 = Robert A.|last3 = Hegele|doi=10.1016/s0021-9150(02)00364-7}}</ref> Furthermore, [[Fish oil|fish oil supplement]] studies have failed to support claims of preventing [[Myocardial infarction|heart attacks]] or [[stroke]]s.<ref name="NYT-20150917-cz">{{cite news |last=Zimmer |first=Carl |author-link=Carl Zimmer |title=Inuit Study Adds Twist to Omega-3 Fatty Acids' Health Story |url=https://www.nytimes.com/2015/09/22/science/inuit-study-adds-twist-to-omega-3-fatty-acids-health-story.html |date=September 17, 2015 |work=[[The New York Times]]|access-date=October 11, 2015 }}</ref><ref name="NYT-20150330">{{cite news |last=O'Connor |first=Anahad |title=Fish Oil Claims Not Supported by Research |url=http://well.blogs.nytimes.com/2015/03/30/fish-oil-claims-not-supported-by-research/ |date=March 30, 2015 |work=[[The New York Times]]|access-date=October 11, 2015 }}</ref><ref name="JAMA-201403">{{cite journal |last1=Grey |first1=Andrew |last2=Bolland |first2=Mark |title=Clinical Trial Evidence and Use of Fish Oil Supplements |url=http://archinte.jamanetwork.com/article.aspx?articleid=1787690 |date=March 2014 |journal=[[JAMA Internal Medicine]] |volume=174 |issue=3 |pages=460–462 |doi=10.1001/jamainternmed.2013.12765 |access-date=October 11, 2015 |pmid=24352849}}</ref>--> |
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[[Whaling]] largely targeted the collection of blubber: whalers [[Rendering (food processing)|rendered]] it into [[whale oil|oil]] in [[try pot]]s, or later, in vats on [[factory ship]]s. The oil could serve in the manufacture of soap, leather, and cosmetics.<ref name="donovan">{{cite encyclopedia | last = Donovan | first = Greg | title = Whaling | encyclopedia = Microsoft Encarta | year = 2008}}</ref> |
[[Whaling]] largely targeted the collection of blubber: whalers [[Rendering (food processing)|rendered]] it into [[whale oil|oil]] in [[try pot]]s, or later, in vats on [[factory ship]]s. The oil could serve in the manufacture of soap, leather, and cosmetics.<ref name="donovan">{{cite encyclopedia | last = Donovan | first = Greg | title = Whaling | encyclopedia = Microsoft Encarta | year = 2008}}</ref> Whale oil was used in candles as wax, and in [[oil lamp]]s as fuel. A single [[blue whale]] can yield a blubber harvest of up to 50 tons.<ref name="Cetacean">{{cite encyclopedia | title = Cetacean | encyclopedia = Encyclopædia Britannica. Ultimate Reference Suite | year = 2008}}</ref> |
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===Health=== |
===Health=== |
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Blubber from whales and seals contains [[omega-3 fatty acids]] and [[vitamin D]].<ref>{{cite journal |
Blubber from whales and seals contains [[omega-3 fatty acids]] and [[vitamin D]].<ref>{{cite journal |last1=Kuhnlein |first1=H.V. |author-link=Harriet V. Kuhnlein |last2=Barthet |first2=V. |last3=Farren |first3=A. |last4=Falahi |first4=E. |last5=Leggee |first5=D. |last6=Receveur |first6=O. |last7=Berti |first7=P. |year=2006 |title=Vitamins A, D, and E in Canadian Arctic traditional food and adult diets |journal=Journal of Food Composition and Analysis |volume=19 |issue=6–7 |pages=495–506 |doi=10.1016/j.jfca.2005.02.007}}</ref> Without the vitamin D, for example, the Inuit and other natives of the Arctic would likely suffer from [[rickets]]. There is evidence blubber and other fats in the arctic diet also provide the calories needed to replace the lack of carbohydrates which are found in the diets of cultures in the rest of the world.<ref>{{cite web|url=http://courses.washington.edu/bioa101/articles/article41.pdf|title=The Inuit Paradox|website=Washington.edu|url-status=live|archive-url=https://web.archive.org/web/20110608052245/http://courses.washington.edu/bioa101/articles/article41.pdf|archive-date=8 June 2011}}</ref> |
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===Toxicity=== |
===Toxicity=== |
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In the 21st century, blubber contains man-made [[polychlorinated biphenyl]] (PCBs), carcinogens that damage human nervous, immune, and reproductive systems.<ref>{{cite journal |doi=10.1126/science.1106882 |
In the 21st century, blubber contains man-made [[polychlorinated biphenyl]] (PCBs), carcinogens that damage human nervous, immune, and reproductive systems.<ref>{{cite journal |doi=10.1126/science.1106882 |title=Two Abundant Bioaccumulated Halogenated Compounds Are Natural Products |year=2005 |last1=Teuten |first1=E. L. |journal=Science |volume=307 |issue=5711 |pages=917–20 |pmid=15705850 |last2=Xu |first2=L |last3=Reddy |first3=CM|bibcode=2005Sci...307..917T |s2cid=9377016 }} |
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* {{cite press release |date=18 February 2005 |title=Chemical Compounds Found In Whale Blubber Are From Natural Sources, Not Industrial Contamination |website=ScienceDaily |url=https://www.sciencedaily.com/releases/2005/02/050213132247.htm}}</ref><ref>{{cite web | url=http://news.bbc.co.uk/2/hi/science/nature/1132889.stm | title=Japan warned on 'contaminated' blubber | work=BBC News | date=2001-01-24 | access-date=2009-12-31 | url-status=live | archive-url=https://web.archive.org/web/20090223093530/http://news.bbc.co.uk/2/hi/science/nature/1132889.stm | archive-date=23 February 2009}}</ref> The source of PCB concentrations is unknown. Since toothed whales are high on the [[food chain]], they likely consume large amounts of industrial pollutants ([[biomagnification|bioaccumulation]]); even [[baleen whale]]s, by merit of the huge amount of food they consume, are bound to have toxic chemicals stored in their bodies. Additionally, there are high levels of [[Mercury (element)|mercury]] in the blubber of seals of the [[Northern Canada|Canadian arctic]].<ref>{{cite journal|last1=Braune|first1=B|title=Persistent organic pollutants and mercury in marine biota of the Canadian Arctic: An overview of spatial and temporal trends|journal=Science of the Total Environment|date=16 August 2005|volume=351–352|pages=32|url=http://web4.uwindsor.ca/users/f/fisk/main.nsf/0/48abbaa50ed52cc08525724a006839ac/$FILE/STOTEN%202005%20Braune%20spatial%20temporal%20cont%20Arctic.pdf|bibcode=2005ScTEn.351....4B|doi=10.1016/j.scitotenv.2004.10.034|pmid=16109439|access-date=26 February 2018|archive-date=10 August 2017|archive-url=https://web.archive.org/web/20170810004605/http://web4.uwindsor.ca/users/f/fisk/main.nsf/0/48abbaa50ed52cc08525724a006839ac/%24FILE/STOTEN%202005%20Braune%20spatial%20temporal%20cont%20Arctic.pdf|url-status=dead}}</ref> |
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==See also== |
==See also== |
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| Line 52: | Line 54: | ||
* [[Muktuk]] (whale blubber and skin as consumed in the North American and East Siberian Arctic) |
* [[Muktuk]] (whale blubber and skin as consumed in the North American and East Siberian Arctic) |
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* [[Whale meat]] |
* [[Whale meat]] |
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* [[Whale oil]] |
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==References== |
==References== |
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| Line 62: | Line 63: | ||
| title= Education Resources for Teachers--Blubber Experiment |
| title= Education Resources for Teachers--Blubber Experiment |
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| url-status= dead |
| url-status= dead |
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| archive-url= https://web.archive.org/web/20080417170650/http://www.marinemammalcenter.org/learning/education/teacher_resources/blubber.asp |
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| archive-date= 17 April 2008 }} |
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| df= dmy-all |
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}} |
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* {{cite web |
* {{cite web |
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| url= http://www.athropolis.com/arctic-facts/fact-blubber-whale.htm |
| url= http://www.athropolis.com/arctic-facts/fact-blubber-whale.htm |
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| Line 77: | Line 76: | ||
[[Category:Marine mammals]] |
[[Category:Marine mammals]] |
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[[Category:Inuit cuisine]] |
[[Category:Inuit cuisine]] |
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[[Category: |
[[Category:Animal fats]] |
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[[Category:American cuisine]] |
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[[Category:Canadian cuisine]] |
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Latest revision as of 20:13, 5 December 2024
Blubber is a thick layer of vascularized adipose tissue under the skin of all cetaceans, pinnipeds, penguins, and sirenians. It was present in many marine reptiles, such as ichthyosaurs and plesiosaurs.[1]
Description
[edit]Lipid-rich, collagen fiber-laced blubber comprises the hypodermis[2] and covers the whole body, except for parts of the appendages. It is strongly attached to the musculature and skeleton by highly organized, fan-shaped networks of tendons and ligaments, can comprise up to 50 per cent of the body mass of some marine mammals during some points in their lives, and can range from 5 cm (2 in) thick in dolphins and smaller whales, to more than 30 cm (12 in) thick in some bigger whales, such as right and bowhead whales. However, this is not indicative of larger whales' ability to retain heat better, as the thickness of a whale's blubber does not significantly affect heat loss. More indicative of a whale's ability to retain heat is the water and lipid concentration in blubber, as water reduces heat-retaining capacities, and lipid increases them.[3]
Function
[edit]Blubber is the primary fat storage on some mammals, specifically those that live in water. It is particularly important for species that feed and breed in different parts of the ocean. During these periods, the animals metabolize fat. Blubber may save energy for marine mammals, such as dolphins, in that it adds buoyancy while swimming.[4]
Blubber differs from other forms of adipose tissue in its extra thickness, which provides an efficient thermal insulator, making blubber essential for thermoregulation. Blubber is more vascularized—rich in blood vessels—than other adipose tissue.
Blubber has advantages over fur (as in sea otters) in that, though fur retains heat by holding pockets of air, the air expels under pressure (i.e., when the animal dives). Blubber, however, does not compress under pressure. It is effective enough that some whales can dwell in temperatures as low as 4 °C (40 °F).[5] While diving in cold water, blood vessels covering the blubber constrict and decrease blood flow, thus increasing blubber's efficiency as an insulator.[6]
Blubber aids buoyancy and streamlines the body, because the organized, complex collagenous network supports the noncircular cross sections characteristic of cetaceans. The buoyancy of blubber could be problematic for bottom-feeding marine mammals such as sirenians and the extinct marine sloths, both of which do or probably did have limited amounts of it for that reason.[7][8]
Research[9] into the thermal conductivity of the common bottlenose dolphin's blubber reveals its thickness and lipid content vary greatly amongst individuals and across life history categories. Blubber from emaciated dolphins is a poorer insulator than that from nonpregnant adults, which in turn have a higher heat conductivity than blubber from pregnant females and adolescents.
Human influences
[edit],_Simon%27s_Town_SA.jpg)
Uses
[edit]Uqhuq,[10] or uqsuq,[11] ("blubber" in the Inuktitut language) is an important part of the traditional diets of the Inuit and of other northern peoples, because of its high energy value and availability. Whale blubber, which tastes like arrowroot biscuits, has similar properties.[12]
Whaling largely targeted the collection of blubber: whalers rendered it into oil in try pots, or later, in vats on factory ships. The oil could serve in the manufacture of soap, leather, and cosmetics.[13] Whale oil was used in candles as wax, and in oil lamps as fuel. A single blue whale can yield a blubber harvest of up to 50 tons.[14]
Health
[edit]Blubber from whales and seals contains omega-3 fatty acids and vitamin D.[15] Without the vitamin D, for example, the Inuit and other natives of the Arctic would likely suffer from rickets. There is evidence blubber and other fats in the arctic diet also provide the calories needed to replace the lack of carbohydrates which are found in the diets of cultures in the rest of the world.[16]
Toxicity
[edit]In the 21st century, blubber contains man-made polychlorinated biphenyl (PCBs), carcinogens that damage human nervous, immune, and reproductive systems.[17][18] The source of PCB concentrations is unknown. Since toothed whales are high on the food chain, they likely consume large amounts of industrial pollutants (bioaccumulation); even baleen whales, by merit of the huge amount of food they consume, are bound to have toxic chemicals stored in their bodies. Additionally, there are high levels of mercury in the blubber of seals of the Canadian arctic.[19]
See also
[edit]- Globster
- Greenlandic cuisine
- Muktuk (whale blubber and skin as consumed in the North American and East Siberian Arctic)
- Whale meat
References
[edit]- ^ "Incredible Jurassic ichthyosaur fossil still has skin and blubber". Science. 5 December 2018. Retrieved 12 January 2024.
- ^ Struntz, D.J.; McLellan, W.A.; Dillaman, R.M.; Blum, J.E.; Kucklick, J.R.; Pabst, D.A. (2004). "Blubber development in bottlenose dolphins (Tursiops truncatus)". Journal of Morphology. 259 (1): 7–20. doi:10.1002/jmor.10154. PMID 14666521. S2CID 24897702.
- ^ Kvadsheim, P.H.; Folkow, L.P.; Blix, A.S. (1996). "Thermal conductivity of minke whale blubber". Journal of Thermal Biology. 21 (2): 123–8. doi:10.1016/0306-4565(95)00034-8.
- ^ "Bouncy Blubber". Science Update. AAAS. Archived from the original on 21 September 2013.
- ^ "Secrets of the Ocean Realm". Archived from the original on 4 May 2017.
- ^ Galbraith, Don; et al. Biology 11. Canada: McGraw-Hill Ryerson. p. 12.
- ^ Horgan, P.; Booth, D.; Nichols, C.; Lanyon, J. M. (2014). "Insulative capacity of the integument of the dugong (Dugong dugon): thermal conductivity, conductance and resistance measured by in vitro heat flux". Marine Biology. 161 (6): 1395–1407. doi:10.1007/s00227-014-2428-4. S2CID 83824482.
- ^ Amson, E.; Argot, C.; McDonald, H. G.; de Muizon, C. (2015). "Osteology and functional morphology of the axial postcranium of the marine sloth Thalassocnus (Mammalia, Tardigrada) with paleobiological implications". Journal of Mammalian Evolution. 22 (4): 473–518. doi:10.1007/s10914-014-9280-7. S2CID 16700349.
- ^ Dunkin, R. C. (2005). "The ontogenetic changes in the thermal properties of blubber from Atlantic bottlenose dolphin Tursiops truncatus". Journal of Experimental Biology. 208 (8): 1469–80. doi:10.1242/jeb.01559. PMID 15802671.
- ^ Ohokak, G.; M. Kadlun; B. Harnum. Inuinnaqtun-English Dictionary (PDF). Kitikmeot Heritage Society. Archived from the original (PDF) on 4 September 2012. Retrieved 6 March 2013.
- ^ "Blubber". Asuilaak Living Dictionary. November 2016.[permanent dead link]
- ^ Stefansson, Eero; Adriaensen, Arxontis (1893). Missionärer bland Eskimåer [Missionaries Among the Eskimos]. Uppdrag i Världen (in Swedish). Göteborg: Himmelriket på Jorden Publikationer. p. 138.
- ^ Donovan, Greg (2008). "Whaling". Microsoft Encarta.
- ^ "Cetacean". Encyclopædia Britannica. Ultimate Reference Suite. 2008.
- ^ Kuhnlein, H.V.; Barthet, V.; Farren, A.; Falahi, E.; Leggee, D.; Receveur, O.; Berti, P. (2006). "Vitamins A, D, and E in Canadian Arctic traditional food and adult diets". Journal of Food Composition and Analysis. 19 (6–7): 495–506. doi:10.1016/j.jfca.2005.02.007.
- ^ "The Inuit Paradox" (PDF). Washington.edu. Archived (PDF) from the original on 8 June 2011.
- ^ Teuten, E. L.; Xu, L; Reddy, CM (2005). "Two Abundant Bioaccumulated Halogenated Compounds Are Natural Products". Science. 307 (5711): 917–20. Bibcode:2005Sci...307..917T. doi:10.1126/science.1106882. PMID 15705850. S2CID 9377016.
- "Chemical Compounds Found In Whale Blubber Are From Natural Sources, Not Industrial Contamination". ScienceDaily (Press release). 18 February 2005.
- ^ "Japan warned on 'contaminated' blubber". BBC News. 24 January 2001. Archived from the original on 23 February 2009. Retrieved 31 December 2009.
- ^ Braune, B (16 August 2005). "Persistent organic pollutants and mercury in marine biota of the Canadian Arctic: An overview of spatial and temporal trends" (PDF). Science of the Total Environment. 351–352: 32. Bibcode:2005ScTEn.351....4B. doi:10.1016/j.scitotenv.2004.10.034. PMID 16109439. Archived from the original (PDF) on 10 August 2017. Retrieved 26 February 2018.
External links
[edit]- "Education Resources for Teachers--Blubber Experiment". Archived from the original on 17 April 2008.
- "Arctic Facts-Blubber".