Mammals of the Mammals of the BadlandsBadlands

By Christina HurleyBy Christina Hurley

Badlands:Badlands:Geologic HistoryGeologic History

Started forming about 75 million years ago Started forming about 75 million years ago

Are composed of 6 different formationsAre composed of 6 different formations Pierre ShalePierre Shale Yellow MoundsYellow Mounds Chadron FormationChadron Formation Brule FormationBrule Formation Rockyford AshRockyford Ash Sharps FormationSharps Formation

Pierre ShalePierre Shale

Deposited 69-75 mya by shallow inland Deposited 69-75 mya by shallow inland seasea

Black mud hardened to shaleBlack mud hardened to shale

Fossil clams, ammonites, and sea reptiles Fossil clams, ammonites, and sea reptiles have been foundhave been found

Yellow MoundsYellow Mounds

Weathered black ocean mudWeathered black ocean mud Had been exposed from formation of the Had been exposed from formation of the

Black HillsBlack Hills

Example of fossil soil (paleosol)Example of fossil soil (paleosol)

Chadron FormationChadron Formation

Deposited 34-37 myaDeposited 34-37 mya

River flood plainRiver flood plain New floods would make each depositNew floods would make each deposit

Known for titanotheres fossils (large, Known for titanotheres fossils (large, rhinoceros-like mammals)rhinoceros-like mammals)

Brule FormationBrule Formation

Deposited 30-34 myaDeposited 30-34 mya

Open savannahOpen savannah

Bands of sandstone show riversBands of sandstone show rivers

Red bands paleosolRed bands paleosol

Oreodonts (sheep-like animals) dominatedOreodonts (sheep-like animals) dominated

Rockyford AshRockyford Ash

Volcanic AshVolcanic Ash

Bottom layer of Sharps FormationBottom layer of Sharps Formation

Serves as a boundary between Sharps Serves as a boundary between Sharps and Brule Formationsand Brule Formations

Sharps FormationSharps Formation

28-30 million years old28-30 million years old

Deposited by wind and waterDeposited by wind and water

Volcanic eruptions from the west provided Volcanic eruptions from the west provided ashash

PaleontologyPaleontology

HyracodonHyracodon

SubhyracodonSubhyracodon

MetamynodonMetamynodon

Tapiroids ColodonTapiroids Colodon

ProtapirusProtapirus

MesohippusMesohippus

MiohippusMiohippus

ArchaeotheriumArchaeotherium

ProtocerasProtoceras

HyaenodonHyaenodon

PoebrotheriumPoebrotherium

OreodontOreodont

NimravidNimravid

HesperocyonHesperocyon

HesperocyonHesperocyon

HesperocyonHesperocyon

““Mongoose-like mammal”Mongoose-like mammal”

One of the earliest Canidae family One of the earliest Canidae family membersmembers

Spent little time in the trees and hunted Spent little time in the trees and hunted mostly on the groundmostly on the ground

Had retractable claws to allow ground Had retractable claws to allow ground walking and climbing trees walking and climbing trees

“There once was a goose named Mon. He was a mongoose.” – Allison Moon

Mesohippus celerMesohippus celer

Mesohippus celerMesohippus celer

Means “middle horse”Means “middle horse”

Appeared suddenly Appeared suddenly (geologically (geologically speaking)speaking)

Preceding horses had Preceding horses had 4 toes, Mesohippus 4 toes, Mesohippus only had 3only had 3

Cerebral hemispheres Cerebral hemispheres notably largernotably larger Brain more distinctly Brain more distinctly

equineequine

Last 3 premolars are Last 3 premolars are like the 3 molarslike the 3 molars Like today’s horses Like today’s horses

have 6 grinding cheek have 6 grinding cheek teethteeth

Leptauchenia nitidaLeptauchenia nitida (Oreodont) (Oreodont)

Leptauchenia nitidaLeptauchenia nitida (Oreodont) (Oreodont)

Called “ruminants hogs”Called “ruminants hogs”

Have distinctive canine teethHave distinctive canine teeth

High set eyes and nostrils suggest aquatic High set eyes and nostrils suggest aquatic life-stylelife-style

Clawed toes indicate terrestrial habitatClawed toes indicate terrestrial habitat

Debated whether it is related to pigs or Debated whether it is related to pigs or sheepsheep It’s a SHIG!It’s a SHIG!

NimravidsNimravids

NimravidsNimravids

Are not saber-toothed cats, not even true Are not saber-toothed cats, not even true catscats

Illustrates parallel evolutionIllustrates parallel evolution

Differences are:Differences are: Paths of various nerve and blood vessels in Paths of various nerve and blood vessels in

skull are more primitiveskull are more primitive Lack a two-chambered auditory bullaLack a two-chambered auditory bulla Teeth are more coned shapedTeeth are more coned shaped

No modern relatives – truly extinctNo modern relatives – truly extinct

B - nimravid; A, C - felids; D - marsupial

Illustration of different evolution theories. Third being the most current.

ConclusionConclusion

Hesperocyon – brought dogs down from Hesperocyon – brought dogs down from the treesthe trees

Mesohippus celerMesohippus celer – 4 toes down to 3, – 4 toes down to 3, more equine like brainmore equine like brain

Oreodont – importance still unknownOreodont – importance still unknown

Nimravids – shows parallel evolutionNimravids – shows parallel evolution

ReferencesReferences

http://fossilmuseum.net/Fossil_Sites/badlands.htmlhttp://fossilmuseum.net/Fossil_Sites/badlands.htmlhttp://fossilmuseum.net/Fossil_Galleries/Mammalia/http://fossilmuseum.net/Fossil_Galleries/Mammalia/Oreodont/Oreodont.htmOreodont/Oreodont.htmhttp://talkorigins.org/faqs/horses/horse_evol.htmlhttp://talkorigins.org/faqs/horses/horse_evol.htmlhttp://laelaps.wordpress.com/2007/06/28/just-what-is-a-http://laelaps.wordpress.com/2007/06/28/just-what-is-a-nimravid-anyway/nimravid-anyway/http://www.nps.gov/badl/upload/07Newspaper.pdfhttp://www.nps.gov/badl/upload/07Newspaper.pdfWarren, Dean M.. Warren, Dean M.. Small Animal Care and ManagementSmall Animal Care and Management. . 2. Thomson Delmar Learning, 2002. 2. Thomson Delmar Learning, 2002.