The earliest mammal ancestors scampered around underneath the feet of giant dinosaurs, surviving as rodent-like creatures. New discoveries in China, however, now indicate that they may have soared overhead as well. Two recently analyzed, 160 million-year-old fossils, have shown evidence of being the first gliding mammals. Or at least the earliest yet discovered. The time period they were dated back to makes them contemporary with the dinosaurs.
First Gliding Mammals – Primitive Flying Squirrels?
The study regarding the fossils was authored by scientists at the University of Chicago and released in the journal Nature. In it, they examined specimens from two different species. These had long finger bones and also presented evidence of wing-like membranes. This means that the volant lifestyle, or life flying between the trees, evolved in ancient mammals almost 100 million years before it was traced in modern mammals.
“These Jurassic mammals are truly the first in glide,” says Zhe-Xi Luo co-author of the two papers. “In a way, they got the first wings among all mammals. With every new mammal fossil from the Age of Dinosaurs, we continue to be surprised by how diverse mammalian forerunners were in both feeding and locomotor adaptations.”
Luo then pointed out that the groundwork for the successful present-day diversification of mammals seems “to have been laid long ago.”
The ability to remain among the trees was an advantage for these creatures both in finding food and avoiding the plethora of predators in times contemporary with the dinosaurs. These first gliding mammals, Maiopatagium furculiferum, and Vilevolodon diplomylos, eventually died out. However, they are considered forerunners to modern mammals.
These animals existed long before flowers evolved. So they must have fed on an entirely different herbivorous diet than most of their modern descendants. The first gliding mammals are also an indication that early mammals were perhaps far more diverse than previously thought, and that they inhabited more potential habitats.
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