sentences:  Young "Albertosaurus" are relatively large for juvenile animals, but their remains are still rare in the fossil record compared with adults.It has been suggested that this phenomenon is a consequence of life history, rather than bias, and that fossils of juvenile "Albertosaurus" are rare because they simply did not die as often as adults did.A hypothesis of "Albertosaurus" life history postulates that hatchlings died in large numbers, but have not been preserved in the fossil record due to their small size and fragile construction.