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Post Info TOPIC: Ancient mammal
Blobrana


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Juramaia sinensis
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Title: A Jurassic eutherian mammal and divergence of marsupials and placentals
Authors: Zhe-Xi Luo, Chong-Xi Yuan, Qing-Jin Meng & Qiang Ji

Placentals are the most abundant mammals that have diversified into every niche for vertebrates and dominated the world's terrestrial biotas in the Cenozoic. A critical event in mammalian history is the divergence of eutherians, the clade inclusive of all living placentals, from the metatherian-marsupial clade. Here we report the discovery of a new eutherian of 160 Myr from the Jurassic of China, which extends the first appearance of the eutherian-placental clade by about 35 Myr from the previous record, reducing and resolving a discrepancy between the previous fossil record and the molecular estimate for the placental-marsupial divergence. This mammal has scansorial forelimb features, and provides the ancestral condition for dental and other anatomical features of eutherians.
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Blobrana


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RE: Ancient mammal
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Mammals' large brains evolved for smell

A highly developed sense of smell kick-started the development of mammals' big brains.
Scientists used very high-resolution scanning to study the skulls of two of the earliest known mammal species.
Comparing the shape of their brain cases to those of slightly earlier animals, or "pre-mammals", revealed that the first brain areas to over-develop were those associated with the sense of smell.
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Blobrana


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Mammals
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How land mammals evolved to be so massive

Although the today's awe-inspiritng African Bush Elephant (Loxodonta africana) might seem a mighty beast, it's a fraction of the size of ancient mammals that roamed the Earth 37 million to 2.7 million years ago.
The Eocene and Oligocene's Indricotherium measured in at more than five meters tall, and the Miocene and Pleistocene's Deinotherium likely weighted some 17,000 kilograms. But how did these mammals shoot up from their mostly miniature predecessors that lived during the age of the dinosaurs - and what kept them from getting even bigger?
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Blobrana


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Timor's extinct giant rat
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Archaeological research in East Timor has unearthed the bones of the biggest rat that ever lived, with a body weight around 6 kg.
The cave excavations also yielded a total of 13 species of rodents, 11 of which are new to science. Eight of the rats weighed a kilogram or more.
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RE: Ancient mammal
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Dinosaur-Chewing Mammals Leave Behind Oldest Known Tooth Marks

Paleontologists have discovered the oldest mammalian tooth marks yet on the bones of ancient animals, including several large dinosaurs. They report their findings in a paper published online June 16 in the journal Paleontology.
Nicholas Longrich of Yale University and Michael J. Ryan of the Cleveland Museum of Natural History came across several of the bones while studying the collections of the University of Alberta Laboratory for Vertebrate Palaeontology and the Royal Tyrrell Museum of Palaeontology. They also found additional bones displaying tooth marks during fieldwork in Alberta, Canada. The bones are all from the Late Cretaceous epoch and date back about 75 million years.
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Blobrana


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Palaeontologists have discovered two mammal hairs encased in 100 million-year-old amber.
While older 2D fossilised hairs are known, those preserved in the amber are the oldest 3D specimens known.
The hairs, found alongside a fly pupa in amber uncovered in southwest France, are remarkably similar to hair found on modern mammals.
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-- Edited by Blobrana on Monday 14th of June 2010 11:28:15 AM

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Blobrana


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Hispaniolan solenodon
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Conservationists are in the Dominican Republic to save one of the world's strangest and most ancient mammals - the Hispaniolan solenodon.
After days of searching, the team finally tracks down one of the bizarre beasts.
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Conservationists are in the Dominican Republic attempting to save one of the world's most strange and ancient mammals - the Hispaniolan solenodon.
While trying to track down one of these creatures, The Last Survivors team is also trying to find out exactly how this animal has been able to survive for a remarkable 76 million years.
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RE: Ancient mammal
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A newly-published report describes the discovery of two new prehistoric rodents in Utah believed to be about 8 million years old.
The site, in central Utah near Sevier, has since been the site of the discovery of several hundred vertebrate fossils, including those belonging to extinct camels, carnivores and elephants.
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Palaeontologists Discover New Fossil Mammal
Palaeontologists in the U.S. and China have discovered a new species of mammal that lived 123 million years ago in what is now the Liaoning Province in China. The newly discovered chipmunk-sized animal, named Maotherium asiaticus, was found in the famous fossil-rich beds of the Yixian Formation in China.
The fossil mammal, reported in this week's issue of the journal Science, offers an important clue to how the mammalian middle ear evolved. It represents an intermediate stage in the evolutionary process of how modern mammals acquired a middle ear structure.

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