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Description
Two skeletals in under a week? Reminds me of the good old times. You all know Allosaurus, the ultra-common generalist Morrison predator that spans millions of years and multiple different ecosystems across thousands of square kilometers. This is the other of the two specimens that has a detailed osteology, DINO 2560 (formerly UUVP 6000), the holotype of the now defunct Creosaurus/Allosaurus atrox. Ever since the publication of Chure & Loewen (2020)'s official splitting of Allosaurus jimmadseni, it has been difficult to tell for sure which specimens do and do not belong to A.fragilis, which diminishes the famously large size variation of the taxon a little bit. Still, the large AMNH individuals, 290 and 680, probably belong to A.fragilis, representing the upper end of the species's size range (if you discount the undiagnostic "Epanterias"). DINO 2560 itself is more or less an average-sized adult, with the small end of the population being represented by USNM 4734 (www.deviantart.com/randomdinos… ).

References:
-Gilmore, Charles W. (1920). "Osteology of the carnivorous dinosauria in the United States National Museum, with special reference to the genera Antrodemus (Allosaurus) andCeratosaurus" (PDF). Bulletin of the United States National Museum. 110 (110): 1–159. doi :10.5479/si.03629236.110.i .
-Madsen, James H. Jr. (1976). Allosaurus fragilis: A Revised Osteology. Utah Geological Survey Bulletin 109 (2nd ed.).
-Chure, Daniel J. (2000). "Observations on the morphology and pathology of the gastral basket of Allosaurus, based on a new specimen from Dinosaur National Monument". Oryctos. 3: 29–37.
-Chure, D., 2000, A new species of Allosaurus from the Morrison Formation of Dinosaur National Monument (Utah-Colorado) and a revision of the theropod family Allosauridae. Ph.D. dissertation, Columbia University, pp. 1–964
-Campione, N. E.; Evans, D. C.; Brown, C. M.; Carrano, M. T. (2014). "Body mass estimation in non‐avian bipeds using a theoretical conversion to quadruped stylopodial proportions" . Methods in Ecology and Evolution. 5 (9): 913−923.
-Botelho JF, Ossa-Fuentes L, Soto-Acuña S, Smith-Paredes D, Nuñez-León D, Salinas-Saavedra M, et al. New developmental evidence clariﬁes the evolution of wrist bones in the dinosaur–bird transition. PLoS Biol. 2014;12:e1001958.
-Chure, D.J.; Loewen, M.A. (2020). "Cranial anatomy of Allosaurus jimmadseni, a new species from the lower part of the Morrison Formation (Upper Jurassic) of Western North America". PeerJ. 8: e7803.

Description
Two skeletals in under a week? Reminds me of the good old times. You all know Allosaurus, the ultra-common generalist Morrison predator that spans millions of years and multiple different ecosystems across thousands of square kilometers. This is the other of the two specimens that has a detailed osteology, DINO 2560 (formerly UUVP 6000), the holotype of the now defunct Creosaurus/Allosaurus atrox. Ever since the publication of Chure & Loewen (2020)'s official splitting of Allosaurus jimmadseni, it has been difficult to tell for sure which specimens do and do not belong to A.fragilis, which diminishes the famously large size variation of the taxon a little bit. Still, the large AMNH individuals, 290 and 680, probably belong to A.fragilis, representing the upper end of the species's size range (if you discount the undiagnostic "Epanterias"). DINO 2560 itself is more or less an average-sized adult, with the small end of the population being represented by USNM 4734 (www.deviantart.com/randomdinos… ).

References:
-Gilmore, Charles W. (1920). "Osteology of the carnivorous dinosauria in the United States National Museum, with special reference to the genera Antrodemus (Allosaurus) andCeratosaurus" (PDF). Bulletin of the United States National Museum. 110 (110): 1–159. doi :10.5479/si.03629236.110.i .
-Madsen, James H. Jr. (1976). Allosaurus fragilis: A Revised Osteology. Utah Geological Survey Bulletin 109 (2nd ed.).
-Chure, Daniel J. (2000). "Observations on the morphology and pathology of the gastral basket of Allosaurus, based on a new specimen from Dinosaur National Monument". Oryctos. 3: 29–37.
-Chure, D., 2000, A new species of Allosaurus from the Morrison Formation of Dinosaur National Monument (Utah-Colorado) and a revision of the theropod family Allosauridae. Ph.D. dissertation, Columbia University, pp. 1–964
-Campione, N. E.; Evans, D. C.; Brown, C. M.; Carrano, M. T. (2014). "Body mass estimation in non‐avian bipeds using a theoretical conversion to quadruped stylopodial proportions" . Methods in Ecology and Evolution. 5 (9): 913−923.
-Botelho JF, Ossa-Fuentes L, Soto-Acuña S, Smith-Paredes D, Nuñez-León D, Salinas-Saavedra M, et al. New developmental evidence clariﬁes the evolution of wrist bones in the dinosaur–bird transition. PLoS Biol. 2014;12:e1001958.
-Chure, D.J.; Loewen, M.A. (2020). "Cranial anatomy of Allosaurus jimmadseni, a new species from the lower part of the Morrison Formation (Upper Jurassic) of Western North America". PeerJ. 8: e7803.