Walking gaits in Cervidae: all species of deer semi cross-walk, as opposed to ambling
INTRODUCTION
All ruminants walk with subtle gaits, rather awkward to describe.
In an amble, the hind foot is lifted only after the opposite fore is placed.
By contrast, in a semi cross-walk, the hind foot is lifted before the opposite fore is placed.
The footfall-sequence, in reality, varies along a continuum, rather than dichotomously.
However the distinction between amble and semi cross-walk is significant because it potentially affects the balance/stability of the locomotion, as follows:
- in an amble, there is a moment in which two feet are off the ground on the same side (left or right) - which is relatively unstable because it is conducive to tipping to one side. whereas
- in a cross-walk (including a semi cross-walk), the two feet off the ground are on different sides, viz. left fore with right hind, or right fore with left hind - which is relatively stable because it maintains diagonal propping.
CERVUS
Cervus elaphus
semi cross-walking:
cross-walking:
https://www.dreamstime.com/red-deer-hind-crossing-stream-water-close-up-winter-image138050863
Cervus elaphus and Cervus canadensis walking gait in masculine display is cross-walk, not amble
https://www.shutterstock.com/image-photo/red-deer-rutting-season-737170840
https://www.shutterstock.com/video/clip-1017907225-wild-red-deer-stag-walking-bright-morning
Cervus canadensis
Something approaching an amble in Cervus canadensis:
DAMA
RUCERVUS
Rucervus duvaucelii branderi
a particularly clear illustration of semi cross-walking: https://www.youtube.com/watch?v=EBigKO906QY
RUSA
AXIS
ODOCOILEUS
ALCES
Alces alces
https://www.youtube.com/watch?v=VUVBr_jDBcQ
DISCUSSION
I have found that - in contrast to bovids (Bovidae) - there is a surprising consistency in the walking gaits of deer (Cervidae).
In bovids, the tendency is that cover-dependent species semi cross-walk, whereas 'plains game' amble.
For example:
-cover-dependent bovid: https://www.istockphoto.com/video/kudu-walking-gm472607841-9062520
- 'plains game' bovid:
This is behaviourally and ecologically correlated, as follows:
- Cover-dependent bovids tend to be nocturnal, solitary, and camouflage-coloured, with eyes facing somewhat forward.
- By contrast, 'plains game' are adapted to living in the open, with diurnal habits, gregariousness, conspicuous colouration, and eyes so far on the sides of the head that they can scan behind and in front at the same time.
The pronghorn (Antilocapra americana) belongs to a different family, viz. Antilocapridae. It conforms to the 'plains game' category, and ambles accordingly (https://es.123rf.com/photo_30436381_pronghorn-antelope-p%C3%A9rez.html).
Impalas (Aepycerotini) are a particularly interesting tribe of bovids, combining a superficially deer-like appearance with multifaceted peculiarities (https://www.inaturalist.org/posts/89229-an-index-to-my-posts-about-the-impala-aepyceros-melampus#). They seem cover-dependent, but actually conform in various ways to the 'plains game'.
Accordingly, impalas consistently amble:
- Aepyceros melampus (https://www.africaimagelibrary.com/media/e65dbf22-af1f-4b33-aea2-6e62423423c9-impala-ram-aepyceros-melampus-gondwana-game-reserve-south-af)
- Aepyceros petersi (https://www.alamy.com/black-faced-impala-aepyceros-melampus-petersi-male-walking-on-savanna-etosha-national-park-namibia-image396537387.html?imageid=130B7753-D07F-4AAF-B8A8-6326847D55ED&p=157727&pn=1&searchId=2cfc4de9b1aacee4e55653a80467551f&searchtype=0 and https://www.alamy.com/male-black-faced-impala-aepyceros-melampus-petersi-by-a-waterhole-etosha-national-park-namibia-with-a-marabou-stork-in-the-background-image214783551.html?imageid=C85EC920-7966-4CB3-97DA-59AF08E61176&p=564807&pn=1&searchId=2cfc4de9b1aacee4e55653a80467551f&searchtype=0 and https://www.alamy.com/stock-photo-black-faced-impala-103307129.html?imageid=59C58C12-F2FE-449E-B7D9-860AD06CF8CC&p=310217&pn=1&searchId=2cfc4de9b1aacee4e55653a80467551f&searchtype=0).
The bovid Kobus defassa is comparable in body size and shape to the cervid Cervus canadensis. However, the former sometimes ambles (https://front.motionarray.com/stock-video/common-waterbuck-walking-between-trees-1179445/), whereas the latter barely achieves an amble under any circumstances: