New Jurassic shuotheriid fossils provide insights into the origin and evolution of pseudotribosphenic teeth, challenging the conventional understanding and revealing the earliest diversification of mammaliaform dental structures.
Fossils of two Jurassic mammaliaforms document the gradual loss of load-bearing function in the articular-quadrate jaw joint, a key prerequisite for the detachment of post-dentary bones and the eventual formation of the mammalian middle ear.