ANN ARBOR, Mich.---A new investigation of a fossilized tracksite in southern Africa shows how early dinosaurs made on-the-fly adjustments to their movements to cope with slippery and sloping terrain. Differences in how early dinosaurs made these adjustments provide insight into the later evolution of the group.
The research, conducted by researchers at the University of Michigan, Argentina's Universidad de Buenos Aires, and the Iziko South African Museum in Cape Town, South Africa, will be published online Oct. 6 in the open-access journal PLoS ONE.
The Moyeni tracksite in Lesotho contains more than 250 footprints made by a variety of four-legged animals near the beginning of the Jurassic Period (about 200 million years ago), when the Earth's landmasses were united as Pangea. The site was first discovered and described in the 1960s and 1970s by French paleontologist Paul Ellenberger but has not since been examined in detail. In their re-analysis of the fossil tracksite, the researchers created a high-resolution map of trackway surface using a combination of traditional mapping techniques and a 3D surface scanner, which recorded millimeter-scale detail. The digital record of the site will serve as an archive and will be the source of future research, said U-M's Jeffrey Wilson, an assistant professor in the Department of Geological Sciences and an assistant curator in the Museum of Paleontology.
The researchers' re-interpretation of the geology of the tracksite indicated that the dinosaurs were walking across an ancient point bar that presented the animals with varying surface conditions. Based on the map, scans, and first-hand observations at the site, Wilson and coworkers Claudia Marsicano and Roger Smith interpreted the tracks to understand how dinosaurs adjusted to changes in terrain as they moved between a wet riverbed, a sloping bank, and a flat, upper surface of the point bar.
"Tracks and trackways bring anima
|Contact: Nancy Ross-Flanigan|
University of Michigan