We’ve noted many times over the years how inconsistent pneumatic features are in sauropod vertebra. Fossae and formamina vary between individuals of the same species, and along the spinal column, and even between the sides of individual vertebrae.

If you followed along with the last post in this series, you now have some bird vertebrae to play with. Here are some things to do with them. 1. Learn the parts of the vertebrae, and compare them with those of other animals Why are we so excited about bird vertebrae around here?

In a recent post I showed photos of the trachea in a rhea, running not along the ventral surface of the neck but along the right side. I promised to show that this is not uncommon, that the trachea and esophagus of birds are usually free to slide around under the skin and are not constrained to like along the ventral midline of the neck, as they usually are in mammals. Here goes.