Editing Torvosaurus (section)

== Paleobiology ==
[[File:Torvosaurus gurneyi teeth.png|thumb|Teeth of ''Torvosaurus gurneyi''.]]
The study of fossilized embryos of ''Torvosaurus'' provides researchers with information about the transformation of the embryo over time, the different developmental pathways present in dinosaur lineages, dinosaur reproductive behavior, and dinosaur parental care.<ref>Long, J. A. & McNamara, K. J. Heterochrony: The key to dinosaur evolution. in The Dinofest International (Wolberg, D.L., Stump, E. & Rosenberg, G. D., eds.) 113–123 ( Acad. Nat. Sci. Phil. , 1997).</ref><ref>Balanoff, A. M., Norell, M. A., Grellet-Tinner, G. & Lewin, M. R. Digital preparation of a probable neoceratopsian preserved within an egg, with comments on microstructural anatomy of ornithischian eggshells. Naturwissenschaften 95 , 493–500 (2008).</ref><ref>Varricchio, D. J. ''et al.'', 2008. Avian paternal care had dinosaur origin. Science 322 , 1826– 1828.</ref> In 2013, Araújo ''et al''. announced the discovery of specimen ML1188, a clutch of crushed dinosaur eggs and embryonic material attributed to ''Torvosaurus''.<ref name="Auraújo" /> This discovery further supports the hypothesis that large theropods were oviparous, meaning that they laid eggs and hence that embryonic development occurred outside the body of female dinosaurs. This discovery was made in 2005 by the Dutch amateur fossil-hunter Aart Walen at the [[Lourinhã Formation]] in Western Portugal in fluvial overbank sediments that are considered to be from the Tithonian age of the [[Jurassic]], approximately 152 to 145 million years ago. This discovery is paleontologically significant for a number of reasons: (a) these are the most primitive dinosaur embryos known; (b) these are the only basal theropod embryos known; (c) fossilized eggs and embryos are rarely found together; (d) it represents the first evidence of a one-layered eggshell for theropod dinosaurs; and (e) it allows researchers to link a new eggshell morphology to the osteology of a particular group of theropod dinosaurs.<ref name="Auraújo">{{Cite journal |last1= Arau´jo |first1=Ricardo |first2=Rui |last2=Castanhinha |first3=Rui M. S. |last3=Martins |first4=Octa´vio |last4=Mateus |first5=Christophe |last5=Hendrickx |first6=F. |last6=Beckmann |first7=N. |last7=Schell |first8=L. C. |last8=Alves |date=2013 |title=Filling the gaps of dinosaur eggshell phylogeny: Late Jurassic Theropod clutch with embryos from Portugal |journal=Scientific Reports |volume=1924 |pages=8 |doi=10.1038/srep01924 |pmid=23722524 |pmc=3667465 |bibcode=2013NatSR...3.1924A |s2cid=7766400 }}</ref> The specimen is housed at the [[Museu da Lourinhã]] in Portugal. As the eggs were abandoned due to unknown circumstances, it is not known if ''Torvosaurus'' provided parental care to its eggs and young or abandoned them shortly after laying.<ref>{{Cite web | url=http://www.nbcnews.com/science/rare-find-abandoned-dinosaur-nests-eggshells-6C10843146 | title=A rare find: Abandoned dinosaur nests with eggshells | website=[[NBC News]] | date=August 5, 2013 | access-date=August 7, 2013 | archive-date=August 3, 2021 | archive-url=https://web.archive.org/web/20210803224131/https://www.nbcnews.com/science/rare-find-abandoned-dinosaur-nests-eggshells-6C10843146 | url-status=live }}</ref> However, the eggshells are highly porous, allowing efficient gaseous exchange between the external and internal media, thus indicating the eggs were buried for incubation within substrate in a manner similar to modern seaturtles. This is also corroborated by the undisturbed taphonomic setting and low-energy geological context.<ref name="Auraújo" />

All documented ''Torvosaurus'' specimens from the [[Morrison Formation]] are from similarly sized, likely adult individuals and the lack of immature individuals may be explained by many factors, none of which are mutually exclusive. For one thing, the formation is known to preserve large vertebrates better than smaller ones. Immature individuals may also have occupied a different ecological niche from adults in habitats where their remains were likely to preserve as fossils and they may have been the prey of choice of larger predators as well. ''Torvosaurus'' may also have experienced Type B1 population survivorship, as has been found in other dinosaurs, with mortality increasing after sexual maturity was achieved, leading to an abundance of mature individuals in the fossil record. A final possibility is that immature ''Torvosaurus'' remains could be misidentified due to having different proportions compared to the very large and robust adults.<ref name=":4" />