Fossil of 165 Million-Year-Old Mammalian Squirrel-Sized Creature Discovered
Posted on August 7, 2013
The fossil of 165 million-year-old mammalian squirrel-sized creature has been discovered in Inner Mongolia, China by scientists from the University of Chicago. Megaconus mammaliaformis co-existed with feathered dinosaurs in the Jurassic era, nearly 100 million years before Tyrannosaurus rex roamed the Earth. Megaconus mammaliaformis is only the second known pre-mammalian fossil with fur.
Megaconus was about the size of a large ground squirrel. Scientists believe it probably walked like modern armadillos. Megaconus had spurs that were probably poisonous. It likely fed on plants, insects, worms and possibly other small vertebrates.
Zhe-Xi Luo, professor of organismal biology and anatomy at University of Chicago, said in a release, "We finally have a glimpse of what may be the ancestral condition of all mammals, by looking at what is preserved in Megaconus. It allows us to piece together poorly understood details of the critical transition of modern mammals from pre-mammalian ancestors."
Luo also says, "We cannot say that Megaconus is our direct ancestor, but it certainly looks like a great-great-grand uncle 165 million years removed. These features are evidence of what our mammalian ancestor looked like during the Triassic-Jurassic transition. Megaconus shows that many adaptations found in modern mammals were already tried by our distant, extinct relatives. In a sense, the three big branches of modern mammals are all accidental survivors among many other mammaliaform lineages that perished in extinction."
The research paper about Megaconus was published here in the journal, Nature.