I was excited to read that the largely complete fossil remains of an ancient proto-mammal lineage previously known from scattered dental remains were found in Outer Mongolia.
The fossil of Megaconus, as the critter was named, was characterized by a furry pelt, but it had a primitive middle ear- the three tiny "bones" in the mammalian ear are derived from bones in the original reptilian jaw, and Megaconus retains this primitive condition. The discovery of this mammaliform specimen indicates that furry mammal ancestors are approximately as old as the dinosaurs, both lineages dating to the late Triassic. For those who aren't total paleontology nerds, the iconic Dimetrodon, which dates back to the Permian, is actually more closely related to we humans than it is to dinosaurs.
The discovery of a largely complete proto-mammal of this age is an awesome boon to those who study evolution. It's nice to get a good idea of what your great, great, great, great, great, great (need I go on?) grand-uncle looks like. Hey, how about a nice musical number from They Might Be Giants, relevant to this subject?
Here's Part 1 of a video series on the evolution of the mammals:
Getting to know the family is such a pleasure!