Modern mammals evolved from within a larger group of animals called cynodonts. Their early forms had a jaw joint that was made of two completely different bones–the quadrate of the skull and the ...

The arrangement of the bones that form the joint (the articulation) between the lower jaw and the skull is a key hallmark of vertebrates. Their configuration has long been used to draw a line in the ...

Breakthroughs, discoveries, and DIY tips sent six days a week. Terms of Service and Privacy Policy. Mammals are defined by how and what we eat every single day of our ...