Hypotheses about the evolution of birds and bird flight form two themes:

I. Did birds evolve from coelurosaur, therapod dinosaurs? and

II. Did flight originate as a cooption of gliding behavior or cursorial ("ground-running/jumping") locomotion?

We will discuss the origin of birds first on Tuesday, then on Thursday we will discuss the origin of flight. You will see that these are not totally independent.

Each person has been assigned a "Theropod" or "non-Theropod" hypothesis. You should examine the papers below for a discussion in class. You will be asked to work in teams to identify and critique the basic arguments for each position You will then be asked to compare the quality of arguments and identify the kind of data needed to resolve disagreements. If you were assigned to the “theropod origin” hypothesis, you should focus on the “cursorial origin of flight” hypothesis, while the “non-theropod origin” group should focus on the “gliding origin of flight” hypothesis.

I. Feduccia et al., 2005, Journal of Morphology vs. Xu et al., 2003, Nature.

II. Hedenstrom, 2002, TREE vs. Chatterjee & Templin, 2003, Naturwissenschaften.