Theropoda

[[File:Longest theropods.svg|alt=Graph showing relative sizes of five types of dinosaur compared with small human figure, each represented by silhouettes in different colours|thumb|upright=2.0|Size comparison of selected giant theropod [[dinosaur]]s – the longest (left) is ''[[Spinosaurus|Spinosaurus aegyptiacus]]'', shortest (right) is ''[[Carcharodontosaurus|Carcharodontosaurus saharicus]]''.]]

[[File:Longest theropods.svg|alt=Graph showing relative sizes of five types of dinosaur compared with small human figure, each represented by silhouettes in different colours|thumb|upright=2.0|Size comparison of selected giant theropod [[dinosaur]]s – the longest (left) is ''[[Spinosaurus|Spinosaurus aegyptiacus]]'', shortest (right) is ''[[Carcharodontosaurus|Carcharodontosaurus saharicus]]''.]]

[[File:Bee hummingbird (Mellisuga helenae) adult male in flight-cropped.jpg|thumb|An adult male [[bee hummingbird]], the smallest known theropod and the smallest [[Neontology|living]] dinosaur]]

[[File:Bee hummingbird (Mellisuga helenae) adult male in flight-cropped.jpg|thumb|An adult male [[bee hummingbird]], the smallest known theropod and the smallest [[Neontology|living]] dinosaur]]

''[[Tyrannosaurus]]'' was for many decades the largest and best-known theropod to the general public. Since its discovery, however, a number of other, comparably-sized giant carnivorous dinosaurs have been described, including ''[[Spinosaurus]]'', ''[[Carcharodontosaurus]]'', and ''[[Giganotosaurus]]''.{{cite journal |last1=Therrien |first1=F. |last2=Henderson |first2=D. M. |year=2007 |title=My theropod is bigger than yours...or not: estimating body size from skull length in theropods |journal=Journal of Vertebrate Paleontology |volume=27 |issue=1 |pages=108–115 |doi=10.1671/0272-4634(2007)27[108:MTIBTY]2.0.CO;2|s2cid=86025320 }} These large theropod dinosaurs are estimated exceed ''Tyrannosaurus'' in length, though more recent studies and reconstructions show that ''Tyrannosaurus'', although shorter, was more heavily built and thus still comparable to them in mass and overall size. The largest known ''Tyrannosaurus'' specimens such as [[Sue (dinosaur)|Sue]] and [[Scotty (dinosaur)|Scotty]] are currently [[estimated]] to be the most massive individual theropod specimens known to science, though by only a narrow margin; a considerable bias in sample size resulting the much greater number of adult specimens in ''Tyrannosaurus'' compared to all other theropods of similar mass, combined with the majority of individual adult giant theropods (even with ''Tyrannosaurus'') never having entered the fossil record, mean it is difficult to judge which, if any, of these theropods was the largest by mass in reality.{{Cite journal |last1=Mallon |first1=Jordan C. |last2=Hone |first2=David W. E. |date=July 24, 2024 |title=Estimation of maximum body size in fossil species: A case study using ''Tyrannosaurus rex'' |journal=[[Ecology and Evolution]] |language=en |volume=14 |issue=7 |article-number=11658 |doi=10.1002/ece3.11658 |issn=2045-7758 |pmc=11267449 |pmid=39050661|bibcode=2024EcoEv..1411658M }} There is still no clear explanation for exactly why giant theropods grew to be so massive compared to any land predators that came before and after them.

''[[Tyrannosaurus]]'' was for many decades the largest and best-known theropod to the general public. Since its discovery, however, a number of other, comparably-sized giant carnivorous dinosaurs have been described, including ''[[Spinosaurus]]'', ''[[Carcharodontosaurus]]'', and ''[[Giganotosaurus]]''.{{cite journal |last1=Therrien |first1=F. |last2=Henderson |first2=D. M. |year=2007 |title=My theropod is bigger than yours...or not: estimating body size from skull length in theropods |journal=Journal of Vertebrate Paleontology |volume=27 |issue=1 |pages=108–115 |doi=10.1671/0272-4634(2007)27[108:MTIBTY]2.0.CO;2|s2cid=86025320 }} These large theropod dinosaurs are estimated to exceed ''Tyrannosaurus'' in length, especially in the case of ''Spinosaurus'', though more recent studies and reconstructions show that ''Tyrannosaurus'', although shorter, was more heavily built and thus still comparable to them in mass and overall size. The largest known ''Tyrannosaurus'' specimens such as [[Sue (dinosaur)|Sue]] and [[Scotty (dinosaur)|Scotty]] are currently [[estimated]] to be the most massive individual theropod specimens known to science, though by only a narrow margin; a considerable bias in sample size resulting the much greater number of adult specimens in ''Tyrannosaurus'' compared to all other theropods of similar mass, combined with the majority of individual adult giant theropods (even with ''Tyrannosaurus'') never having entered the fossil record, mean it is difficult to judge which, if any, of these theropods was the largest by mass in reality.{{Cite journal |last1=Mallon |first1=Jordan C. |last2=Hone |first2=David W. E. |date=July 24, 2024 |title=Estimation of maximum body size in fossil species: A case study using ''Tyrannosaurus rex'' |journal=[[Ecology and Evolution]] |language=en |volume=14 |issue=7 |article-number=11658 |doi=10.1002/ece3.11658 |issn=2045-7758 |pmc=11267449 |pmid=39050661|bibcode=2024EcoEv..1411658M }} There is still no clear explanation for exactly why giant theropods grew to be so massive compared to any land predators that came before and after them.

The largest extant theropod is the [[common ostrich]], up to 2.74 m (9 ft) tall and weighing between 90 and 130 kg (200 – 290 lb).{{cite web|url = http://www.awf.org/wildlife-conservation/ostrich|title = Ostrich|website = African Wildlife Foundation|access-date = 28 October 2020}} The smallest non-avian theropod known from adult specimens is the [[Troodontidae|troodontid]] ''[[Anchiornis|Anchiornis huxleyi]]'', at 110 grams in weight and 34 centimeters (1 ft) in length. When modern birds are included, the [[bee hummingbird]] (''Mellisuga helenae'') is smallest at 1.9 g and 5.5 cm (2.2 in) long.{{cite journal |last1=Brusatte |first1=Stephen L. |last2=O'Connor |first2=Jingmai K. |last3=Jarvis |first3=Erich D. |title=The Origin and Diversification of Birds |journal=Current Biology |date=October 2015 |volume=25 |issue=19 |pages=R888–R898 |doi=10.1016/j.cub.2015.08.003 |pmid=26439352 |doi-access=free |bibcode=2015CBio...25.R888B |hdl=10161/11144 |hdl-access=free }}{{cite web |last1=Hendry|first1=Lisa |title=Are birds the only surviving dinosaurs? |url=https://www.nhm.ac.uk/discover/why-are-birds-the-only-surviving-dinosaurs.html |publisher=The Trustees of The Natural History Museum, London |access-date=14 April 2023 |date=2023}}

The largest extant theropod is the [[common ostrich]], up to 2.74 m (9 ft) tall and weighing between 90 and 130 kg (200 – 290 lb).{{cite web|url = http://www.awf.org/wildlife-conservation/ostrich|title = Ostrich|website = African Wildlife Foundation|access-date = 28 October 2020}} The smallest non-avian theropod known from adult specimens is the [[Troodontidae|troodontid]] ''[[Anchiornis|Anchiornis huxleyi]]'', at 110 grams in weight and 34 centimeters (1 ft) in length. When modern birds are included, the [[bee hummingbird]] (''Mellisuga helenae'') is smallest at 1.9 g and 5.5 cm (2.2 in) long.{{cite journal |last1=Brusatte |first1=Stephen L. |last2=O'Connor |first2=Jingmai K. |last3=Jarvis |first3=Erich D. |title=The Origin and Diversification of Birds |journal=Current Biology |date=October 2015 |volume=25 |issue=19 |pages=R888–R898 |doi=10.1016/j.cub.2015.08.003 |pmid=26439352 |doi-access=free |bibcode=2015CBio...25.R888B |hdl=10161/11144 |hdl-access=free }}{{cite web |last1=Hendry|first1=Lisa |title=Are birds the only surviving dinosaurs? |url=https://www.nhm.ac.uk/discover/why-are-birds-the-only-surviving-dinosaurs.html |publisher=The Trustees of The Natural History Museum, London |access-date=14 April 2023 |date=2023}}