Research Interests
I am a vertebrate paleontologist and paleobiologist studying early mammals and recovery from extinction events.
Early mammalian evolution, especially phylogeny and biogeography of multituberculate mammals
Although the Cenozoic is called “The Age of Mammals,” mammalian history began in the Mesozoic, and early mammals were quite diverse. Multituberculates, sometimes called the “rodents of the Mesozoic,” lived on all the northern continents by the Late Cretaceous. They are the most diverse and most commonly identified terrestrial vertebrates that survive the end-Cretaceous extinction and re-diversify afterward.
Terrestrial recovery from the end-Cretaceous mass extinction
The extinction at the end of the Cretaceous Period, 65 million years ago, is the most recent mass extinction event in Earth's history. The fossil record of this event and of the subsequent biotic recovery is particularly good in marine sediments, where it is documented in geologic sections around the world. Our record of this event in terrestrial sediments is not as complete. The best terrestrial record of this interval is from the Western Interior of North America, where the mammalian fossil record is exceptional, and there are age constraints on many local and regional faunas. I am particularly interested in how biogeographic variation in the Late Cretaceous might have contributed to recovery of terrestrial ecosystems in the earliest Cenozoic.
Evolutionary properties governing biotic response to extinction on large spatiotemporal scales
Is there a general pattern of recovery from extinction events? And if so, does a general set of evolutionary properties govern biotic response to, and recovery from, environmental perturbation? Regardless of the quality of the local data on any individual extinction or recovery period, such events are only interpretable if their variation from more general baselines is known.
Instructional Activities
- Gross and Developmental Anatomy – MS I
- Biomedical Statistics – Graduate
- Evolution and Development of the Mammalian Skull – Graduate
Recent Publications
Williamson, T. E., Nichols, D. J., and Weil, A. 2008. Paleocene palynomorph assemblages from the Nacimiento Formation, San Juan Basin, New Mexico, and their biostratigraphic significance. New Mexico Geology 30(1):3-11.
Drea, C. and Weil, A. 2007, 2008. External genital morphology of the Ringtailed Lemur (Lemur catta): females are naturally ‘masculinized’ Journal of Morphology, online publication Oct. 2007; print publication in April, 2008 269:451-463.
(abstract) Weil, A. and Pignataro, F. M. 2007. Dietary inferences from dental microwear in multituberculate mammals from the Hell Creek and Tullock Formations of Eastern Montana. Journal of Vertebrate Paleontology 27(3): 163-164A.
(abstract) Weil, A. 2007. The role of biogeographic heterogeneity and mammalian faunal exchange in recovery from the Cretaceous-Tertiary extinction event. Bulletin de la Société géologique de France. Abstract volume p. 100.
(abstract) Weil, A. and Pignataro, F. M., 2007. Dental Microwear in Multituberculate Mammals and Dietary change across the K/T boundary in eastern Montana. Journal of Morphology 268(12):1148.
(abstract) Weil, A., and Williamson, T. 2007. Late Cretaceous through earliest Tertiary evolution of multituberculate mammals in the San Juan Basin of New Mexico, and their biogeographic context. Geological Society of America Abstracts with Programs 39(3):15.
