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Ground sloth
" The Princeton Field Guide to Prehistoric Mammals " present referee to many charismatic and bizarre mammals from the distant past , offer a coup d’oeil of the peculiar word form that come before mammals active today .
Swimming ground slothThalassoconuslived in what is now Peru and Chile during the late Miocene epoch , from about 12 million to 5 million years ago .
Deinotherium
Deinotheriumlived during the Oligocene era , 34 million to 23 million years ago . It was heavy and had longer stage than the modern elephant it resembles , and had low tusks that curled down and backwards , toward its body .
Sea cow
The extinct giant Steller ’s ocean cow , Hydrodamalis gigas , was described in the mid-18th century , and was as openhanded as some whales — up to 30 substructure ( 9 beat ) in length .
Carpolestes
Tarsier - likeCarpolesteswas a primate relative from the Paleocene era , 66 million to 55 million twelvemonth ago . It had grok hand like a primate , and be in trees , as do many modern primate .
Nuralagus rex
A modern hare is overshadow byNuralagus male monarch . This mammoth rabbit lived during the Pliocene epoch , 5 million to 2.6 million geezerhood ago , on the island of Minorca , in the Mediterranean Sea off the seacoast of Spain .
Chasmoporthetes
A reconstruction ofChasmoporthetes , a hyena with long legs for bunk . It lived in Eurasia and North America during the Pliocene ( 5 million to 2.6 million geezerhood ago ) and Pleistocene ( 2.6 million year ago until 10,000 years ago ) epochs .
Enhydriodon dikikae
East Africa ’s enormous " bear otter,“Enhydriodon dikikae , lived alongside our earliest ancestors in Ethiopia during the Pliocene epoch , 5 million to 2.6 million years ago .
Trogosus
Trogosusbelonged to an order of out mammals sleep together as the tillodonts , which populate North America , Asia and Europe during the Paleocene ( 66 million to 55 million years ago ) and Eocene ( 55 million to 34 million years ago ) date of reference . Tillodonts had powerful jaws and short , pocket-size braincase .
Morgancudon
Shrew - sizeMorganucodonwas one of the first true mammals , emerging during the Late Triassic period ( 201.3 million to 235 million years ago ) . They had large brain and midget teeth for craunch up insects , much like the teeth of living insectivorous mammals .
Volaticotherium
Volaticotheriumhad delicate limbs and a sailplaning membrane similar to those in modern flight squirrels or sugar glider . It lived in Mongolia during the Jurassic period , 199.6 million to 145.5 million twelvemonth ago .
Behemotops
Hippo - likeBehemotopslived during the Late Oligocene , 28.4 million to 23 million year ago , populate marine waters , brackish river lip and lagoons , keeping close to the shoring . It probably spent most of its fourth dimension in the water system and had eye positioned at the top of its head so it could see while its body was full immerse .
