amnhnyc: One of the first jawed vertebrates and one of the largest of the armored fishes called placoderms, Dunkleosteous was an aggressive predator. Serrated jawbones regenerated as they were worn down, and stayed razor-sharp by rubbing against the

amnhnyc: One of the first jawed vertebrates and one of the largest of the armored fishes called placoderms, Dunkleosteous was an aggressive predator. Serrated jawbones regenerated as they were worn down, and stayed razor-sharp by rubbing against the

tags: Command Center,

from: https://terranghost.tumblr.com/post/150203081508