"Alligator eggs are an ideal self-contained unit for studying the effects of oxygen on development they have a limited food source in the yolk and they are incubated in their nesting material at a constant temperature of 89F and 100 percent relative humidity," said John Vanden Brooks, a graduate student in the Department of Geology and Geophysics at Yale University. He noted that large-scale changes in atmospheric partial oxygen pressure would have had wide-ranging effects on vertebrate evolution and development throughout geologic time.
Understanding the environment's effect on vertebrate evolution and development is essential to the study of ecology, paleontology and evolutionary theory. Oxygen is the most important component in the atmosphere for all vertebrate animals, and while the rise in oxygen level during the Precambrian era has been widely studied, little attention has previously been paid to continued fluctuations throughout the Phanerozoic. His mentor, Robert A. Berner, the Alan M. Bateman Professor of Geology and Geophysics at Yale, characterized the range of atmospheric oxygen levels over multimillion year times scales, and established an upper value of about 31 percent oxygen, and a sharp decline near the Permo-Triassic boundary to about 12 percent. Earth's current atmosphere is about 21 percent oxygen.
"Each clutch contains 30 50 eggs that are laid together, so easy comparison can be made between sibling eggs raised under differe
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Contact: Janet Rettig Emanuel
janet.emanuel@yale.edu
203-432-2157
Yale University
3-Aug-2005