A pintail duck egg, partially developed embryo, and recently hatched chick lined up to illustrate the progression of development.

A black tern nest with three eggs.

Close view of a pelican chick just emerging from its shell. William L. Finley visible in the background.

A black tern nest with three eggs.

A black tern nest with three eggs. Image note: large.

Herbert Brown standing beside a cholla cactus looking at a Palmer thrasher nest.

Pyrrhuloxia sitting in nest with open mouth. Image note: small size.

Pyrrhuloxia sitting in nest with open mouth. Image note: small size.

Pyrrhuloxia on nest with mouth open. Image note: side view, small size.

Pyrrhuloxia on nest with mouth open. Image note: small size, not very good.