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 You are here: Social Behaviour > Herding

Herding is a common behaviour in both herbivorous mammals and birds. It gives individuals added protection from predators for themselves and their offspring and makes finding food a much easier prospect. There are two major lines of fossil evidence which show that herbivorous dinosaurs also roamed in herds during the Mesozoic.

Fossil trackways
Dinosaur fossil trackways have been found for several different groups including sauropods, hadrosaurs and coelurosaurs. Fossil trackways of hadrosaurs and sauropods have been found consisting of the footprints of several individuals of different sizes within a same bedding plane. The footprints in such a trackway frequently go in the same direction and in some cases change direction together, this has been observed in the trackways of hadrosaurs in Peace River Canyon, Canada.

This provides excellent evidence that dinosaurs often travelled in herds consisting of adults and juveniles. In addition to this a sauropod trackway from Oxfordshire, UK shows two distinct types of sauropod footprint which appear to come from two very distinct species. This suggests that these dinosaurs may have formed mixed herds in the same way as some African herbivores do today.

Mass mortality
Body remains of dinosaurs have been food in massive aggregations where a single catastrophic event has overwhelmed and buried groups of individuals. One example of this is a bone bed of the ceratopsian, Centosaurus in the Dinosaur Park Formation, Canada. Here massive and rapid flooding engulfed and buried the remains of a large number of individuals including juveniles, the remains however are fragmented. A smaller scale but excellently preserved example is of the basal ceratopsian, Psittacosaurus in Liaoning, China. Here six individuals of mixed ages were preserved after being killed in a Lahar event. Such assemblages of hadrosaurs also provide evidence for mixed herding as often two or more species can be found adjacent to one another other.

Together with fossil trackways these fossil assemblages show that herbivorous dinosaurs did live in herds containing individuals of different ages, probably for mutual protection from predators. There is also evidence that mixed herds also formed possibly as different species followed similar migration roots.


W.A.S. Sarjeant, Fossil Vertebrate Footprints, Geology Today (July-August 1988) 125-130.
J.J. Day, D.B. Norman, A.S. Gale, P. Upchurch and H.P. Powell. A Middle Jurassic Dinosaur Trackway Site From Oxfordshire, UK, Palaeontology, Vol. 47 (2004) 319–348.
Q. Zhou, P.M. Barrett, D.A. Eberth, Social Behaviour and Mass Mortality in the Basal Ceratopsian Dinosaur Psittacosaurus (Early Cretaceous, People’s Republic of China), Palaeontology, Vol. 50, (2007) 1023–1029.
M.J. Ryan, A.P. Russell, D.A. Eberth, P.J. Currie, The Taphonomy of a Centrosaurus (Ornithischia: Certopsidae) Bone Bed from the Dinosaur Park Formation (Upper Campanian), Alberta, Canada, with Comments on Cranial Ontogeny, PALAIOS, Vol. 16, (2001), 482-506.
M.J. Benton, Vertebrate Palaeontology 3ed. Blackwell Publishing, (2005) pg 209.


© 2008 Earth Sciences, University of Bristol