1-1 Thursday, Jan. 5 08:30 - 08:45 Is high complexity unbearable? MOUSTAKAS-VERHO, JE*; STENBERG, OE; ANTTILA, J; JERNVALL, J; Institute of Biotechnology, University of Helsinki; Institute of Biotechnology, University of Helsinki; Integrative Ecology Unit, University of Helsinki; Institute of Biotechnology, University of Helsinki Jacqueline.Moustakas@helsinki.fi http://www.biocenter.helsinki.fi/bi/evodevo/group_jackie.shtml
Bears are an ecomorphologically diverse clade and their dentition reflect the wide range of dietary habits, from the hypercarnivorous polar bear, omnivorous sloth, sun, black, and brown bears to the herbivorous panda bear. The shape of the mammalian dentition is determined prior to eruption and modified only by wear. The complexity of the dentition has been shown to correlate with diet, and we have used this metric to reconstruct the diet of the European cave bear, Ursus spelaeus, a member of the Pleistocene megafauna that went extinct during the Last Glacial Maximum. The teeth of the cave bear exhibit the greatest complexity of all bear species, even higher than panda bears, which are specialized bamboo feeders. This suggests that the dentition of cave bears was highly specialized for a vegetation diet, and may not have been sustainable with changing climates and landscapes. An alternative hypothesis that we investigate is that the cave bear became developmentally unstable and ended up in a complexity trap, unable to further produce adaptive change. We contrast this with the simpler dentition of the polar bear, a population currently experiencing habitat fragmentation.