Question

1) What does the IMI of an animal tell us about their mode of locomotion?

2) (True or False) The glenoid fossa is a landmark on the scapula/ shoulder bone and helps when determining locomotion of an animal

3) Dentition characterized by half moon shaped cusps is called

A. selenodont

B. hypsodont

C. bunodont

D. Carnassial

4. ​Relative to quadrupeds, the foramen magnum of bipeds is more

A. Anterior

B. Posterior

C. Ventral

D. The foramen magnum would be in the same place on a biped and a quadruped

5. (True or False) Natural selection and genetic drift are the same thing

Answer 1

1.Intermembral index are calculated by the ratio of forelimb length and hind limb length. It tells about the primary mode of locomotion in primates such as Swinging/clinging activity ,quadrupedalism,brachiation and bipedalism.

2.True

3.A selenodont

Selenodont is the characteristic of ruminants teeth having crescent shaped(half moon) ridges on the molar teeth. Hypsodont is the characteristic of teeth of cow and horses which has high crowned teetha and enamel extending to the gum .Bunodont type of dentition is refer to mammals where tubercules on the crown of molar teeth can be found.Carnassial type of dentition can be found in carnivores refers to pair of large upper premolar and lower molar teeth have enlarged ,self -sharped edeges for shearing.

4.Anterior

Anterior position of the foramen magnum is the adaptation for maintaining the balance of head realtive to the cervical vertebral column causes orthograde trunk postures during bipedalism.

5. False

In genetic drift ,allele frequencies varies by chance but in natural selection it changes by differential reproductive success.