Herrerasaurus: Difference between revisions

| fossil_range = [[Upper Triassic]] <br/> 231.4 mya

[[File:Herrerasaurusskeleton.jpg|thumb|right|24opx240px|Skeleton of ''Herrerasaurus'' and ''[[Eoraptor]]'']]

''Herrerasaurus'' was a lightly built [[bipedal]] carnivore with a long tail and a relatively small head. Its length is estimated at 3 to 6&nbsp;meters (10 to 20&nbsp;ft),<ref name =Sereno1992>Sereno P.C. and Novas F.E. 1992. The complete skull and skeleton of an early dinosaur. ''Science'' '''258''' (5085): 1137–1140.</ref> and its hip height at more than 1.1&nbsp;meters (3.3&nbsp;ft).<ref name=GSP88>{{cite book|last=Paul G.S. 1988 ''Predatory dinosaurs of the world'' |title=Predatory Dinosaurs of the World: A Complete Illustrated Guide |url=https://archive.org/details/predatorydinosau0000paul |year=1989 |location=New York |publisher=Simon and Schuster |pages=248–250[https://archive.org/details/predatorydinosau0000paul/page/248 248]–250 |isbn=0-671-68733-6}}</ref> It may have weighed around 210–350&nbsp;kilograms (463–772&nbsp;lb).<ref name=GSP88/>

The [[natural environment|paleoenvironment]] of the Ischigualasto Formation (where it was found) was a [[volcanic]]ally active [[floodplain]] covered by [[forests]] with strong seasonal rainfall. The climate was moist and warm,<ref name="TuckerBenton1982">{{citeCite journal| last last1= Tucker, |first1=Maurice E. & |last2=Benton, |first2=Michael J. |date=1982. |title=Triassic environments, climates, and reptile evolution| url=https://linkinghub.elsevier.com/retrieve/pii/0031018282900347|journal = Palaeogeography, Palaeoclimatology, Palaeoecology| language=en|volume = 40| issue = 4| pages = 361–379| url = http://palaeo.gly.bris.ac.uk/benton/reprints/1982triassic.pdf| doi = 10.1016/0031-0182(82)90034-7| access-date = 2009-07-23| title = Archived copy| archive-date = 2009-01-26| archive-url = https://web.archive.org/web/20090126214339/http://palaeo.gly.bris.ac.uk/benton/reprints/1982triassic.pdf| url-status = dead}}</ref> with seasonal variations.<ref name="Columbi2008">{{cite conference| last = Columbi, Carina E. 2008.| title = Stable isotope analysis of fossil plants from the Upper Triassic Ischigualasto Formation in the northwest of Argentina| publisher = The Geological Society of America| location = Houston, Texas| url = http://gsa.confex.com/gsa/2008AM/finalprogram/abstract_151184.htm}}| conference = {{Webarchive| access-date = 2014-01-01| archive-date = 2012-01-11| archive-url = https://web.archive.org/web/20120111145256/http://gsa.confex.com/gsa/2008AM/finalprogram/abstract_151184.htm| |date=2012url-01-11status = dead}}</ref> VegetationThe consistedvegetation ofwas [[fern]]s (''[[Cladophlebis]]''), [[horsetail]]s, and giant [[conifer]]s (''Protojuniperoxylon''). These plants formed lowland forests along the banks of rivers.<ref name="Sereno1992"/> ''Herrerasaurus'' remains appear to have beenwas the most common amongof the carnivores of the Ischigualasto Formation.

''Herrerasaurus'' lived in these jungles alongside a smaller dinosaur, the one metre long ''[[Eoraptor]]'', as well as. ''[[Saurosuchus]]'',<ref>{{citeCite journal|last last1= Sill|first1=W D|last2=Sill|first2=W. D. |date=1974 |title=The anatomy of ''Saurosuchus galilei'' and the relationships of the rauisuchid thecodonts |url=https://www.biodiversitylibrary.org/part/22965|journal=Bulletin of the Museum of Comparative Zoology at Harvard College.|volume=146 |pages=317–362 |issn=0027-4100}}</ref> a huge quadrupedal [[Archosaur]] was the biggest land predator at the time. There were also a number of [[therapsid]] and reptilian herbivores. The dinosaurs had not yet taken control of the land environments as they did later.