Editing Walking (section)

==Animals==
{{main|Terrestrial locomotion}}
{{See also|Gait}}

===Horses===
{{main|Horse gait}}
[[File:Muybridge horse walking animated.gif|thumb|The walk, a four-beat gait]]
The walk is a four-beat gait that averages about {{convert|4|mph|km/h}}. When walking, a horse's legs follow this sequence: left hind leg, left front leg, right hind leg, right front leg, in a regular 1-2-3-4 beat. At the walk, the horse will always have one foot raised and the other three feet on the ground, save for a brief moment when weight is being transferred from one foot to another. A horse moves its head and neck in a slight up and down motion that helps maintain balance.<ref name=Harris33>Harris, Susan E. ''Horse Gaits, Balance and Movement'' New York: Howell Book House 1993 {{ISBN|0-87605-955-8}} pp. 32–33</ref>

Ideally, the advancing rear hoof oversteps the spot where the previously advancing front hoof touched the ground. The more the rear hoof oversteps, the smoother and more comfortable the walk becomes. Individual horses and different [[List of horse breeds|breeds]] vary in the smoothness of their walk. However, a rider will almost always feel some degree of gentle side-to-side motion in the horse's hips as each hind leg reaches forward.{{citation needed|date=July 2018}}

The fastest "walks" with a four-beat footfall pattern are actually the lateral forms of [[ambling]] gaits such as the running walk, singlefoot, and similar rapid but smooth intermediate speed gaits. If a horse begins to speed up and lose a regular four-beat cadence to its gait, the horse is no longer walking but is beginning to either [[Horse gait#Trot|trot]] or pace.{{citation needed|date=July 2018}}

===Elephants===
[[File:Elephant Walking animated.gif|thumb|right|An Asian elephant walking]]
[[Elephants]] can move both forwards and backwards, but cannot [[trot]], [[jumping|jump]], or [[Horse gait|gallop]]. They use only two gaits when moving on land, the walk and a faster gait similar to running.<ref>{{cite journal | last1 = Shoshani | first1 = J. | last2 = Walter | first2 = R. C. | last3 = Abraha | first3 = M. | last4 = Berhe | first4 = S. | last5 = Tassy | first5 = P. | last6 = Sanders | first6 = W. J. | last7 = Marchant | first7 = G. H. | last8 = Libsekal | first8 = Y. | last9 = Ghirmai | first9 = T. | last10 = Zinner | first10 = D. | year = 2006 | title = A proboscidean from the late Oligocene of Eritrea, a "missing link" between early Elephantiformes and Elephantimorpha, and biogeographic implications | journal = Proceedings of the National Academy of Sciences | volume = 103 | issue = 46| pages = 17296–301 | doi=10.1073/pnas.0603689103 | pmid=17085582 | pmc=1859925| bibcode = 2006PNAS..10317296S | doi-access = free }}</ref> In walking, the legs act as pendulums, with the hips and shoulders rising and falling while the foot is planted on the ground. With no "aerial phase", the fast gait does not meet all the criteria of running, although the elephant uses its legs much like other running animals, with the hips and shoulders falling and then rising while the feet are on the ground.<ref name="kinetics">{{cite journal |author = Hutchinson, J. R. |author2=Schwerda, D. |author3=Famini, D. J. |author4=Dale, R. H. |author5=Fischer, M. S. |author6=Kram, R. |name-list-style=amp |year=2006|title=The locomotor kinematics of Asian and African elephants: changes with speed and size|journal=Journal of Experimental Biology|volume=209|issue=19|pages=3812–27|pmid=16985198 |doi = 10.1242/jeb.02443|doi-access=free |bibcode=2006JExpB.209.3812H }}</ref> Fast-moving elephants appear to 'run' with their front legs, but 'walk' with their hind legs and can reach a top speed of {{convert|18|km/h|abbr=on}}.<ref>{{cite journal|author=Genin, J. J.|author2= Willems, P. A. |author3=Cavagna, G. A. |author4=Lair, R. |author5=Heglund, N. C. |name-list-style=amp |year=2010|title=Biomechanics of locomotion in Asian elephants|journal=Journal of Experimental Biology|volume=213|pages=694–706|doi=10.1242/jeb.035436|issue=5|pmid=20154184|doi-access=|bibcode= 2010JExpB.213..694G }}</ref> At this speed, most other [[Quadrupedalism|quadrupeds]] are well into a gallop, even accounting for leg length.

===Walking fish===
{{Main|Walking fish}}
[[File:Periophthalmus gracilis.jpg|thumb|right|A [[mudskipper]], a type of walking fish, perched on land]]
[[Walking fish]] (or ambulatory fish) are [[fish]] that are able to travel over [[Terrestrial ecoregion|land]] for extended periods of time. The term may also be used for some other cases of nonstandard [[fish locomotion]], e.g., when describing fish "walking" along the [[seabed|sea floor]], as the [[handfish]] or [[frogfish]].

=== Insects ===
Insects must carefully coordinate their six legs during walking to produce gaits that allow for efficient navigation of their environment. Interleg coordination patterns have been studied in a variety of insects, including locusts (''Schistocerca gregaria''), cockroaches (''Periplaneta americana''), stick insects (''[[Carausius morosus]]''), and fruit flies (''[[Drosophila melanogaster]]'').<ref name=stick-insect-walking>{{cite journal | vauthors = Graham, DA | title = A behavioural analysis of the temporal organisation of walking movements in the 1st instar and adult stick insect (Carausius morosus) | journal = Journal of Comparative Physiology| volume = 81 | pages = 23–52 | date = 1972 | doi = 10.1007/BF00693548| s2cid = 38878595 }}</ref><ref name=static-stability>{{cite journal | vauthors = Szczecinski NS, Bockemühl T, Chockley AS, Büschges A | title = Static stability predicts the continuum of interleg coordination patterns in Drosophila | journal = The Journal of Experimental Biology | volume = 221 | issue = Pt 22 | pages = jeb189142 | date = November 2018 | pmid = 30274987 | doi = 10.1242/jeb.189142 | doi-access = free }}</ref><ref name=cockroach-walking>{{cite journal | vauthors = Spirito CP, Mushrush DL | title = Interlimb Coordination During Slow Walking in the Cockroach: I. Effects of Substrate Alterations| journal = Journal of Experimental Biology | volume = 78 | pages = 233–243| date = 1979 | doi = 10.1242/jeb.78.1.233| url = https://jeb.biologists.org/content/78/1/233}}</ref> Different walking gaits have been observed to exist on a speed dependent continuum of phase relationships.<ref name=stick-insect-walking /><ref name=cockroach-walking /> Even though their walking gaits are not discrete, they can often be broadly categorized as either a metachronal wave gait, tetrapod gait, or tripod gait.<ref name=insect-walking>{{cite journal | vauthors = Wilson, Donald M | title = Insect Walking | journal = Annual Review of Entomology| volume = 11 | issue = 1 | pages = 103–122 | date = 1966 | pmid = 5321575 | doi = 10.1146/annurev.en.11.010166.000535 | doi-access =  }}</ref>

In a metachronal wave gait, only one leg leaves contact with the ground at a time. This gait starts at one of the hind legs, then propagates forward to the mid and front legs on the same side before starting at the hind leg of the contralateral side.<ref name=insect-walking /> The wave gait is often used at slow walking speeds and is the most stable, since five legs are always in contact with the ground at a time.<ref name=hughes1957>{{cite journal | vauthors = Hughes, GM | title = The Co-Ordination of Insect Movements | journal = Journal of Experimental Biology | volume = 34 | pages = 306–333| date = 1957 | issue = 3 | doi = 10.1242/jeb.34.3.306 | bibcode = 1957JExpB..34..306H | url =https://jeb.biologists.org/content/34/3/306}}</ref>

In a tetrapod gait, two legs swing at a time while the other four legs remain in contact with the ground. There are multiple configurations for tetrapod gaits, but the legs that swing together must be on contralateral sides of the body.<ref name=insect-walking /> Tetrapod gaits are typically used at medium speeds and are also very stable.<ref name=static-stability />

A walking gait is considered tripod if three of the legs enter the swing phase simultaneously, while the other three legs make contact with the ground.<ref name=insect-walking /> The middle leg of one side swings with the hind and front legs on the contralateral side.<ref name=insect-walking /> Tripod gaits are most commonly used at high speeds, though it can be used at lower speeds.<ref name=hughes1957 /> The tripod gait is less stable than wave-like and tetrapod gaits, but it is theorized to be the most robust.<ref name=static-stability /> This means that it is easier for an insect to recover from an offset in step timing when walking in a tripod gait. The ability to respond robustly is important for insects when traversing uneven terrain.<ref name=static-stability />