Light, Toothless beak Large “keeled” sternum Gizzard instead of teeth Tail bones lost/fused Into pygostyle Center of gravity.

Light,Toothlessbeak

Large “keeled”sternum

Gizzard instead of teeth

Tail bones lost/fusedInto pygostyle

Center of gravity

Powering flight

Static soaring

Light or dark meat?

It’s all about flight physiology!

Powering flight muscles

So unidirectional flowWhat’s the advantage??

Cerebellum

Bird Brain

Coordinating flight

Primary cavity nesters

Secondary cavity nesters

AltricialPrecocial

Sex determined by sex chromosomes, not temperature

Attracting a mate

Song from Syrinx“double flute”

MigrationShearwater 40,000 miles/year

If they were burning gasoline instead of fat, they'd be getting about 720,000 miles to the gallon

Blackpoll Warbler15 g ----2 for one stamp 80-90 hours nonstop

Migrate Canada to South AmericaNeotropical migrant Red + yellow =12000 miles