Today – 4/05Today – 4/05

• Critter in the News

• Theropod tree

• theropod metabolism

• Little Das’ Hunt

Last time

Troodon nesting behavior

Evolution of flight

Early gliders

Oviraptor, Gallimimus, and T. rex

Volaticotherium – gliding mammal

About 2.5 oz, 5 inches long, older than 125 Ma, large furry gliding membrane!

Gliding is thought to have arisen 7 times in mammals (more to come!)

Teeth highly specialized for insectivory

Previous oldest flying mammal – 51 Ma bat

Predator / prey ratios

Cold-blooded predators need less food, and so ecosystems can support more of them

1% of biomass is predators in mammals

25% in modern ecosystems with cold-blooded predators

Bones say 3-5% in dinosaurs

Footprints say 15%