The most definitive evidence that dinosaurs traveled in groups comes from sequences of fossilized footprints called trackways. Several track sites have now been found that suggest herding behavior in some groups of dinosaurs. At the Davenport Ranch site outside San Antonio, Texas, R. T. Bird of AMNH discovered an amazing set of sauropods tracks in 1940. Detailed analyses of these trackways reveal a herd of 23 sauropods rambling over muddy ground at a pace of about 2 meters per second. The pattern of overlapping tracks indicates that the largest adult sauropods led the herd, followed by smaller individuals.