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Spinosaurs show semi-aquatic oxygen isotopes

From: Ben Creisler bh480@scn.org

In case this ref has not been mentioned yet:

Oxygen isotope evidence for semi-aquatic habits among 
spinosaurid theropods. 
Romain Amiot, Eric Buffetaut, Christophe Lécuyer, Xu Wang, 
Larbi Boudad, Zhongli Ding, François Fourel, Steven Hutt, 
François Martineau, Manuel Alfredo Medeiros, Jinyou Mo, 
Laurent Simon, Varavudh Suteethorn, Steven Sweetman, 
Haiyan Tong, Fusong Zhang, and Zhonghe Zhou 
Geology 38: 139-142 (February 2010) 

Spinosaurs were large theropod dinosaurs showing peculiar 
specializations, including somewhat crocodile-like 
elongate jaws and conical teeth. Their biology has been 
much discussed, and a piscivorous diet has been suggested 
on the basis of jaw as well as tooth morphology and 
stomach contents. Although fish eating has been considered 
plausible, an aquatic or semiaquatic lifestyle has seldom 
been suggested because of the apparent lack of 
corresponding adaptations in the postcranial skeleton of 
spinosaurs, which on the whole is reminiscent of that of 
other large terrestrial theropods. On the basis of the 
oxygen isotopic composition of their phosphatic remains 
compared with those of coexisting terrestrial theropod 
dinosaurs and semiaquatic crocodilians and turtles, we 
conclude that spinosaurs had semiaquatic lifestyles, i.e., 
they spent a large part of their daily time in water, like 
extant crocodilians or hippopotamuses. This result sheds 
light on niche partitioning between large predatory 
dinosaurs, since spinosaurs coexisted with other large 
theropods such as carcharodontosaurids or tyrannosaurids. 
The likely ichthyophagy and aquatic habits of spinosaurids 
may have allowed them to coexist with other large 
theropods by reducing competition for food and territory.