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Description
Allosaurus fragilis is one of the best known non-bird theropods - plus, it has the very "classic" appeal of a non-coelurosaur tetanuran, with its deep, narrow hatchet-head, powerful hind limbs, and strongly clawed arms. Known from a multitude of specimens, we see what we would see in probably any dinosaur were it known from a multitude of specimens - a good degree of intraspecific variation.

That is, individual allosaurs were quite a bit different. From the short-snouted AMNH 600 on the right, with its conspicuous lacrimal horns and tall nasal ridges atop its snout, over posterchild specimen UUVP 6000 (middle) to the long-snouted AMNH 666 with rather shallow ridges on its nasal bones, there are several Allosaurus fragilis specimens that span a continuum between these extremes. There have been attempts to consider these different species - a common long-snouted one (exemplified by UUVP 6000) and a rare short-snouted (exemplified by USNM 4734), but this has been more or less refuted, as mass death sites contain animals of both "types", and that the famous triangular, big-horned skull of USNM 4734 was misreconstructed.

I originally wanted to include USNM 4734 as well, but the above reasons ruled that out; "Big Al Two" had to go as well, as Scott Hartman informed me that it rather belongs to the earlier undescribed Allosaurus species from Dan Chure's doctoral thesis. All of the specimens are drawn to scale, with - measured in basal skull length - AMNH 666 the biggest. Oh, and Dracontes did something very similar some time ago.

Expect a digital version of my previous allosaur soon-ish, courtesy of a fellow deviant very dear to me.

//Edit: Oh, here's a WIP of that - do go and check it out!

Description
Allosaurus fragilis is one of the best known non-bird theropods - plus, it has the very "classic" appeal of a non-coelurosaur tetanuran, with its deep, narrow hatchet-head, powerful hind limbs, and strongly clawed arms. Known from a multitude of specimens, we see what we would see in probably any dinosaur were it known from a multitude of specimens - a good degree of intraspecific variation.

That is, individual allosaurs were quite a bit different. From the short-snouted AMNH 600 on the right, with its conspicuous lacrimal horns and tall nasal ridges atop its snout, over posterchild specimen UUVP 6000 (middle) to the long-snouted AMNH 666 with rather shallow ridges on its nasal bones, there are several Allosaurus fragilis specimens that span a continuum between these extremes. There have been attempts to consider these different species - a common long-snouted one (exemplified by UUVP 6000) and a rare short-snouted (exemplified by USNM 4734), but this has been more or less refuted, as mass death sites contain animals of both "types", and that the famous triangular, big-horned skull of USNM 4734 was misreconstructed.

I originally wanted to include USNM 4734 as well, but the above reasons ruled that out; "Big Al Two" had to go as well, as Scott Hartman informed me that it rather belongs to the earlier undescribed Allosaurus species from Dan Chure's doctoral thesis. All of the specimens are drawn to scale, with - measured in basal skull length - AMNH 666 the biggest. Oh, and Dracontes did something very similar some time ago.

Expect a digital version of my previous allosaur soon-ish, courtesy of a fellow deviant very dear to me.

//Edit: Oh, here's a WIP of that - do go and check it out!