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onehundred thousand euros a page

Recently, a press release
suggested that the German Science Foundation spent 3 Million Euros to
find that sauropods gulped their food instead of chewing. If I apply
this calculation to the summary paper, they spent 100.000 Euro per

Sander, M. et al. (2010): Biology of the sauropod dinosaurs: the
evolution of gigantism. Biology Reviews (online first)


The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous
periods were the largest terrestrial animals ever, surpassing the
largest herbivorous mammals by an order of magnitude in body mass.
Several evolutionary lineages among Sauropoda produced giants with
body masses in excess of 50 metric tonnes by conservative estimates.
With body mass increase driven by the selective advantages of large
body size, animal lineages will increase in body size until they reach
the limit determined by the interplay of bauplan, biology, and
resource availability. There is no evidence, however, that resource
availability and global physicochemical parameters were different
enough in the Mesozoic to have led to sauropod gigantism.
We review the biology of sauropod dinosaurs in detail and posit that
sauropod gigantism was made possible by a specific combination of
plesiomorphic characters (phylogenetic heritage) and evolutionary
innovations at different levels which triggered a remarkable
evolutionary cascade. Of these key innovations, the most important
probably was the very long neck, the most conspicuous feature of the
sauropod bauplan. Compared to other herbivores, the long neck allowed
more efficient food uptake than in other large herbivores by covering
a much larger feeding envelope and making food accessible that was out
of the reach of other herbivores. Sauropods thus must have been able
to take up more energy from their environment than other herbivores.
The long neck, in turn, could only evolve because of the small head
and the extensive pneumatization of the sauropod axial skeleton,
lightening the neck. The small head was possible because food was
ingested without mastication. Both mastication and a gastric mill
would have limited food uptake rate. Scaling relationships between
gastrointestinal tract size and basal metabolic rate (BMR) suggest
that sauropods compensated for the lack of particle reduction with
long retention times, even at high uptake rates.
The extensive pneumatization of the axial skeleton resulted from the
evolution of an avian-style respiratory system, presumably at the base
of Saurischia. An avian-style respiratory system would also have
lowered the cost of breathing, reduced specific gravity, and may have
been important in removing excess body heat. Another crucial
innovation inherited from basal dinosaurs was a high BMR. This is
required for fueling the high growth rate necessary for a multi-tonne
animal to survive to reproductive maturity.
The retention of the plesiomorphic oviparous mode of reproduction
appears to have been critical as well, allowing much faster population
recovery than in megaherbivore mammals. Sauropods produced numerous
but small offspring each season while land mammals show a negative
correlation of reproductive output to body size. This permitted lower
population densities in sauropods than in megaherbivore mammals but
larger individuals.
Our work on sauropod dinosaurs thus informs us about evolutionary
limits to body size in other groups of herbivorous terrestrial
tetrapods. Ectothermic reptiles are strongly limited by their low BMR,
remaining small. Mammals are limited by their extensive mastication
and their vivipary, while ornithsichian dinosaurs were only limited by
their extensive mastication, having greater average body sizes than