[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Size of *Neoceratodus africanus* and/or *N. tuberculatus*



I admit that the elongate and delicate snout, conical teeth and gape
increase are features common in piscivorous birds, and think there is
no problem for small spinosaurs to be piscivore. However, for the
large adult Spinosaurus, it seems certain that it will have problems
due to its size, in the muddy sides of the rivers, to which it would
have to approach in order to fish. For this reason I would think the
large adult would have to depart and enter less into the river, which
does not imply it can not live near the water bodies. Unless the soil
was not so muddy and even the largest Spinosaurus may have reached the
side of the water body.

Some birds whose elongated bills seem to have originated in relation
with piscivory found their long bills equally useful on land, such as
some egrets, marabou and kingfishers. Because of this, I do not see
much problem in that the large Spinosaurus searched for other ways of
survival if its size prohibited him from appraching the river.

I do not know much of the mechanic arguments regarding spinosaurs, but
think elongation of the snout does not seem to be much comparable in,
on one side, herons and storks, and on the other, choristoderes and
gharials. The first two lunge a fast frontal strike by stretching the
neck and have a basally wide and distally pointing bill, while the two
latter have a snout resembling a cylindrical rod full of small teeth,
and do not suddendly extend their neck to catch fishes, they seem to
better catch the fish with transverse movements (somebody said it was
easier to move a rod under water than a table).

Although I do not deny the piscivory, spinosaurs do not seem to
resemble any of these specialized options in snout morphology.