Download - Stuart S. Sumida / Kathleen Devlin Biology 342

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Page 1: Stuart S.  Sumida / Kathleen Devlin Biology 342

Stuart S. Sumida / Kathleen DevlinBiology 342

Locomotion: High Speed Gaits in Mammalian Herbivores

Page 2: Stuart S.  Sumida / Kathleen Devlin Biology 342

RUNNING GAITS•In four-legged mammals, a running gait is one where some part of the step cycle is spent in suspension – with all for limbs out of contact with the ground

•The most standard high-speed gait in dogs is the rotary gallop.

•The canter is an asymmetrical and infrequently used gait in dogs. When used it is often as a transition from the gallop as the animal is slowing down. It is also sometimes used when playing and the impression of speed is combined with interaction with other animals.

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CANTER•The canter is a 3 beat gait. The beat sequence begins with a rear leg, moves to the paired diagonals and then finally the front leg diagonal to the hind leg in the first beat. The animal is then briefly suspended before the sequence is repeated.

•If the right hind leg strikes the ground it is referred to as a left lead will if the left hind leg strikes the ground first it is a right lead.

•The canter is an infrequently used gait in dogs. When used it is often as a transition from the gallop as the animal is slowing down. It is also sometimes used when playing and the impression of speed is combined with interaction with other animals.

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CANTER (in a horse)

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CANTER - The canter is a 3 beat gait. The beat sequence begins with a rear leg, moves to the paired diagonals and then finally the front leg diagonal to the hind leg in the first beat. The animal is then briefly suspended before the sequence is repeated.

Body tilts forward

Only one diagonal couplet

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Slow “Speed” Sequence: left hind; right hind & left front; right front.(Technically, not really a gallop or a trot.)

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GALLOP

•In four-legged mammals, the highest speed gait is the gallop. It is a four-beat gait, with each limb contacting independant of the other three.

•In horses, the gallop usually has only a single suspension, or floating phase, with the limbs gathered underneath only, and not when extended forward and back.

•The footfall sequence tends to be: right hind, left hind, right, front, left front. (Or left hind, right hind, left front, right front.)

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LH LF RFRH

LH LH

RH RH

LF LF

RF RF

LH

Equine Transverse Gallop with GATHERED floating phase.

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1878 – Eadweard Muybridge, hired by railroad baron Leland Stanford to understand horse locomotion and gait, simultaneously invents gait analysis and the technological basis of motion pictures.

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Bactrian camel in transverse gallop

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Small to medium size herbivores (such as deer) sometimes engage in a rotary gallop.

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Young deer demonstrating rotary gallop and leaping ability

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Deer – transverse gallop