Editing Hummingbird (section)

===Morphology===
Across the estimated 366 species, hummingbird weights range from as small as {{convert|2.0|g}} to as large as {{convert|20|g}}.<ref name="eb-h">{{cite web |title=Hummingbird |url=https://www.britannica.com/animal/hummingbird |publisher=Encyclopaedia Britannica |access-date=7 March 2023 |date=2023}}</ref><ref name="smithsonian">{{cite web |title=What is a hummingbird? |url=https://nationalzoo.si.edu/migratory-birds/hummingbirds |publisher=Smithsonian’s National Zoo and Conservation Biology Institute |access-date=7 March 2023 |date=2023}}</ref> They have characteristic long, narrow beaks (bills) which may be straight (of varying lengths) or highly curved.<ref name=eb-h/><ref name=smithsonian/> The bee hummingbird {{ndash}} only {{convert|6|cm}} long and weighing about {{convert|2|g|oz}} {{ndash}} is the world's smallest bird and smallest [[warm-blooded]] [[vertebrate]].<ref name=eb-h/><ref name=ADW>{{cite web|publisher=Animal Diversity Web|title= ''Mellisuga helenae''|last1= Glick|first1=Adrienne|url= http://animaldiversity.org/accounts/Mellisuga_helenae/|date=2002 |access-date=14 April 2023}}</ref>

Hummingbirds have compact bodies with relatively long, bladelike wings having anatomical structure enabling [[helicopter]]-like flight in any direction, including the ability to hover.<ref name=eb-h/><ref name=smithsonian/> Particularly while hovering, the wing beats produce the humming sounds, which function to alert other birds.<ref name=eb-h/> In some species, the tail feathers produce sounds used by males during courtship flying.<ref name=eb-h/><ref name=smithsonian/> One species of hummingbird &ndash; the [[little woodstar]] (''Chaetocercus bombus'') &ndash; has a wing-beat frequency of 99 per second during hovering.<ref name="wilcox2022">{{Cite journal |last1=Wilcox |first1=Sean |last2=Clark |first2=Christopher |year=2022 |title=Sexual selection for flight performance in hummingbirds |url=https://academic.oup.com/beheco/article/33/6/1093/6686581 |journal=Behavioral Ecology |volume=33 |issue=6 |pages=1093–1106|doi=10.1093/beheco/arac075 |url-access=subscription }}</ref> Such extreme flight demands are supported by a high metabolic rate dependent on foraging for sugars from flower nectar.<ref name=Hargrove/><ref name=smithsonian/>

[[File:Ruby Throated Hummingbird, F, leg, 430 ESt. NW, 8.22.12 2013-04-12-14.49.36 ZS PMax (8644622066).jpg|thumb|Close-up of toe arrangement in a [[ruby-throated hummingbird]] foot, showing three claw-like toes forward and one backward.]]
Hummingbird legs are short with [[Dactyly#Anisodactyly|feet]] having [[Bird feet and legs#Tarsometatarsus|three toes pointing forward and one backward]] {{ndash}} the [[hallux]].<ref name="b&b">{{cite web |first1=Emily |last1=Hannemann |title=Hummingbird feet: Can hummingbirds walk? |url=https://www.birdsandblooms.com/birding/attracting-hummingbirds/hummingbird-feet/ |publisher=Birds&Blooms |access-date=4 April 2023 |date=12 May 2022}}</ref><ref name="scoop">{{cite web |title=Do hummingbirds have feet? |url=https://www.wildbirdscoop.com/do-hummingbirds-have-feet.html |publisher=Wild Bird Scoop |access-date=4 April 2023 |date=2023}}</ref> The toes of hummingbirds are formed as [[claw]]s with ridged inner surfaces to aid gripping onto flower stems or petals.<ref name=scoop/> Hummingbirds do not walk on the ground or hop like most birds, but rather shuffle laterally and use their feet to grip while perching, [[preening]] feathers, or nest-building (by females), and during fights to grab feathers of opponents.<ref name=b&b/><ref name=scoop/>

Hummingbirds apply their legs as [[piston]]s for generating [[thrust]] upon taking flight, although the shortness of their legs provides about 20% less propulsion than assessed in other birds.<ref name="reiser">{{cite journal |last1=Tobalske|first1=Bret W. |last2=Altshuler|first2=Douglas L.|last3=Powers|first3=Donald R.|title=Take-off mechanics in hummingbirds (Trochilidae) |journal=The Journal of Experimental Biology |volume=207 |issue=Pt 8 |pages=1345–52 |date=March 2004 |pmid=15010485 |doi=10.1242/jeb.00889 |s2cid=12323960 |doi-access=free |bibcode=2004JExpB.207.1345T }}</ref> During flight, hummingbird feet are tucked up under the body, enabling optimal [[aerodynamics]] and maneuverability.<ref name=scoop/>

Of those species that have been measured during flight, the top flight speeds of hummingbirds exceed {{Convert|15|m/s|km/h mph|abbr=on}}.<ref name=ADW/> During [[Courtship display|courtship]], some male species dive from {{Convert|30|m|ft|sigfig=1}} of height above a female at speeds around {{Convert|23|m/s|km/h mph|abbr=on}}.<ref>{{Cite journal |last1=Clark |first1=C.J. |last2=Dudley |first2=R. |year=2009 |title=Flight costs of long, sexually selected tails in hummingbirds |journal=Proceedings of the Royal Society B: Biological Sciences |volume=276 |issue=1664 |pages=2109–115 |doi=10.1098/rspb.2009.0090 |pmc=2677254 |pmid=19324747}}</ref><ref>{{Cite book |title=The Birds of Ecuador, Field Guide |last1=Ridgely |first1=R.S.|last2=Greenfield|first2= P.G.|publisher=Cornell University Press |year=2001 |isbn=978-0-8014-8721-7 |edition=1}}</ref>

The sexes differ in feather coloration, with males having distinct brilliance and ornamentation of head, neck, wing, and breast feathers.<ref name=eb-h/><ref name=smithsonian/> The most typical feather ornament in males is the [[gorget (bird)|gorget]] {{ndash}} a bib-like iridescent neck-feather patch that changes brilliance with the viewing angle to attract females and warn male competitors away from territory.<ref name=eb-h/>