the cursorial horse

Question 1

what is the meaning of the word cursorial

Answer 1

• the horse is designed to run fast
• in a straight line
• over relatively flat terrain
• for a distance to sufficiently outrun a predator

Question 2

what causes cursorial success

Answer 2

• maximize speed
• minimize energy expenditure of motion

Question 3

what is the different between carnivores and herbivores

Answer 3

• carnivores attain high speed by using their flaxible spines to maximize stride length; however, this is costly in terms of energy required to attained speed
• the herbivore have rigid spines with minimal lateral or verticle flexibility. the limbs of the horse are also completely deveoted to motion

Question 4

what is speed

Answer 4

• a function of stride rate and stride length
• however they are antagonistic = increasing one means decreasing the other so you have to find optimal balance

Question 5

what is stide length determined by

Answer 5

• limb length = increasing the length of the digits has increase the limb length of the horse
• length of suspension phase

Question 6

how has stride length has been enhanced

Answer 6

• adoption of the unguligrade stance
• increasing the length of distal bones (metacarples, metatarsals, carpals, tarsals, phalanges)
• the absence of the calvical

Question 7

how is stride rate optimized

Answer 7

• reducing the ratio of the length to the body (chest to rump) length
• decreasing distal limb weight (minimize movement of inertia, reduces energy expenditure related to motion
• accomplish by digit reduction and elongation
• concentration of muscle mass proximal to the body
• movement is assisted by a passie mechanism entailing stoarage and release of elastic energy through the tendond
• relatively high proportion of fast-twitch muscle fibres
• increase in stride rate is also related to reducing the energy necessary to move the limbs

Question 8

what features minimize the energy cost of locomotion

Answer 8

• devotion of limbs to locomotion
• reduction in the number of digits
• elongation of the distal limb bones
• reduction of distal limb mass
• reducing teh size of the ulna and fibula ( increase limb stability, decrease rotational and lateral flexion of the limbs, facilitates unidirectional actions of the limbs)
• increasing flexion during protraction( increases elastic energy potential of the tendons)
• long lightweight tendons connect carpus and tarsus to distal limbs ( provide elastic energy to facilitate movement of the limbs)

Question 9

horse movement

Answer 9

decreasing lateral flexibility means that all of the energy transmitted from the caus=dal limbs is translated into forward motion
- the horse minimal ability to move its outside limbs the saggital plane and minimal lateral flexibility of the spine and limbs

Question 10

limb usage for movement

Answer 10

• the mass of the horses limbs it=s optimized by balancing the necessary to keep them light enough the minimize energy required for motion and large enough to provide the strength needed to deliver that motion and to withstand the forces created by running
• fore and hind limb specialization means that the front limbs withstand most of the forces of movement while the back limbs generate the thrust to propel the horse forward