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Reeve's Bonebed

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A geological formation in Presidio county, Texas, with the coordinates of 29.9° N, 104.2° W. It is placed in the late Eocene and early Oligocene.

Geology

Reeves bonebed lies in the Vieja Formation

Ecology

The University of Texas holds a large collection of fossils from Reeves bonebed. The number of specimins held in their collection from the Reeve's Bonebed are displayed in the abundance column[1]:

Mammals

Order Family Genus Abundance Notes

Cetartiodactyla

Merycoidodontidae

Merycoidodon

91

Bathygenys

709/870

hundreds of endocasts (see below)

Leptomerycidae

Hendryomeryx defordi

2/870

Leptomeryx

10/870

Oromerycidae

Eotylopus reedi

1/870

Agriochoeridae

Agriochoerus

15/870

Protoceratidae

Leptotragulus

1/870

Heteromeryx defordi

2/870

Rodentia

Eutypomyidae

Eutypomys inexpectatus

13/870

Ischyromyidae

Pseudotomus johanniculi

1/870

holotype

Leptotomus

1/870

Cylindrodontidae

Ardynomys

1/870

Cylindrodon fontis

3/870

Perissodactyla

Tapiridae

Colodon

4/870

Equidae

Mesohippus

11/870

Hyracodontidae

Hyracodon primus

1/870

Brontotheriidae

Menodus bakeri

1/870

Carnivora

Miacoidea

Miacis cognitus

1/870

holotype

Creodonta

Hyaenodontidae

Hyaenodon

2/870



For fossils of which an exact genus cannot be assigned, there have been discovered...

gastropods

testudinids

Pholidosteids

Oreodont Braincasts

Reeves bonebed is known for the recovery of casts of the brain cavity of oreodonts called endocasts[2]. When and animal dies and the soft tissues decay, sediments fill the orafices left, including the brain case. If the bone falls apart, the fossil that used to be housed on the inside of the skull can remain. Hunreds of brain casts, mainly from Bathygenys, were recovered from Reeves bonebed and have been used to guage the size of the brain as well as the size of the lobes. Physical arrangement of the brain can lead to clues about the life of the living animal, such as how important smell was to it, as used in CT scans of Tyrannosaurus. Studies involving more than 150 of these endocasts have been preformed from the Reeves bonebed samples.[3]

References

  1. ^ University of Texas, Austin. Bonebed&county=&state=&specid=&geol_form=&epoch=&site_no=&showimage=&geog=&country=&others=&geol=&epoch=&period=&age=&era=&strat=&formation=&group=&horizon=&member=&sorted_by= "Reeves bonebed". {{cite web}}: Check |url= value (help)
  2. ^ "Oreodont braincasts".
  3. ^ Macrini, Thomas E. "Description of a Digital Cranial Endocast of Bathygenys reevesi (Merycoidodontidae; Oreodontoidea) and Implications for Apomorphy-Based Diagnosis of Isolated, Natural Endocasts".