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Can’t help but wonder and imagine how apparent the differences would be in life. Who knows what kind of soft tissue was present that could differentiate them? It’s so fun to think about.
Short snout allosaurus is Allosaurus atrox, a morph of Allosaurus fragilis, distinguished by a bit taller but shorter skull
If you don't understand what morph is look at us, we have 3 morphs, Afro,Euro,Asia (actually 2 more morphs but those morphs are extinct as far as i know)
The key difference is in the cheek bone, known as the jugal bone. In Allosaurus fragilis, the jugal has a sharp, downward-pointing projection shaped kinda like a trapezoid. In Allosaurus jimmadseni, the jugal is completely flat and lacks that projection. Its crests are also relatively taller with respect to its skull than Allosaurus fragilis (this is taken from the description paper by Loewen and Chure 2020).
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A. Fragilis is the allosaurus you are used to
A. Jimmadseni in the other hand have different proportions
A. Jimmadseni have proportionally longer neck, proportionally shorter tail and somewhat longer legs, skull is also different
Big Al was a A. Jimmadseni wasn't he?
Yup. She (yup, Al was likely actually female) was thought to be fragilis but was later found to be jimmadseni after that species was established.
Thanks!
What about A. anax, did he look like Gwangi?
We can't say how he looked like, too fragmentary
Currently he is reconstructed after A. Fragilis, with additional details from close relatives
https://preview.redd.it/o4lwmx75e29g1.jpeg?width=250&format=pjpg&auto=webp&s=4f4f7f230567d33fe1d02e081afa2b72155e9654
The skull shapes are the main thing that comes to my mind.
This⬆️as long as uou remember which has which its a very good way to distinguish them
Can’t help but wonder and imagine how apparent the differences would be in life. Who knows what kind of soft tissue was present that could differentiate them? It’s so fun to think about.
So fragilis is the one that looks less fragile, and jimmadseni is the one that looks less Jimmy?
Expertly put
What was the difference between the short snout and long snout Allo morphs? Was there short snout A. Fragilis and long snout, or was it by species?
Short snout allosaurus is Allosaurus atrox, a morph of Allosaurus fragilis, distinguished by a bit taller but shorter skull
If you don't understand what morph is look at us, we have 3 morphs, Afro,Euro,Asia (actually 2 more morphs but those morphs are extinct as far as i know)
Allosaurus atrox is a synonym of allosaurus fraglis
The short snout one was the one less threatening to Ceratosaurus I take it?
? I don't think so, cuz short snouted morph lived in the same areas as ceratosaurus (A. Atrox) , while A. Fragilis lived in different area
Likely differences in the snouts based in different prey, i don't think you'll see stegosaurus in the forests or near bodies of water pretty often
So short snout was actually a cerat competitor to a certain extent? Interesting.... Where did Torvo live, anyway?
The key difference is in the cheek bone, known as the jugal bone. In Allosaurus fragilis, the jugal has a sharp, downward-pointing projection shaped kinda like a trapezoid. In Allosaurus jimmadseni, the jugal is completely flat and lacks that projection. Its crests are also relatively taller with respect to its skull than Allosaurus fragilis (this is taken from the description paper by Loewen and Chure 2020).