1. Primates

Success Criteria

Your learning has been successful if you can do the following:

I can identify and describe the physical traits that are common to all primates.
I can describe the specific physical characteristics associated with brachiators, knuckle-walkers, and bipeds.
I can explain that quadrupeds use all four limbs for locomotion and bipeds use their two rear limbs / feet for locomotion.

Vocabulary

Learn these so you can communicate this concept well.

Larynx (voice box): Helps to create different sounds when we speak.

Do Now: Wordwall task

Explore Your Inner Animals (HHMI Biointeractive)

Primates

Humans belong to the order ‘Primates’ along with prosimians, monkeys and apes.

Video: Odyssey Earth “Primates - What is a Primate?” Run Time: 5:07

Characteristics of Primates

General characteristics of order Primates

Mammals in the order Primate have the following characteristics:

Structural:

Prehensile (grasping) hands and feet - allows them to grip/manipulate objects.
Sometimes a prehensile trail - used for balance.
Nails instead of claws, sensitive finger pads - helps with manipulating objects.
5 functional digits on each foot
Forward facing eyes/overlapping visual field. Allows them to easily see the world in 3D
Good hand-eye coordination
Bony ridges to protect eyes
Tendency toward having an erect upper body - associated with sitting, standing, leaping, and in some, walking.

Physiological:

Oestrus/reproductive cycle of female, 2 nipples
Gestation (pregnancy period) is longer than most other mammals.
Typically have one young per pregnancy

Behavioural:

Longer periods of infant dependency, and large parental investment. This nurturing increases survival rate and allows cultural development.
Highly sociable, greater dependency on highly flexible learned behaviour.

Modes of Primate Locomotion

Most primates are adapted to an arboreal (tree-living) niche. But some have adapted to move on the ground.

Arboreal (tree-dwelling)

Quadrupedalism (on all fours)
Leaping
Brachiation (arm swinging from tree to tree).

Ground

Quadrupedalism (on all fours)
Knuckle-walking (arms hold the fingers in a partially curled posture that allows body weight to press down on the ground through the knuckles).
Bipedalism - habitual (walking on two legs consistently).

Adaptations for Tree Climbing

Long strong arms meaning that their forelimbs are longer than their hindlimbs. This is because tree climbing relies heavily on forelimbs for climbing and arm-hanging/swinging activities.
Curved long fingers, which enabled the primate to grip.
Flexible ankles that allow the primate to hold its body close to the tree, reducing energy it takes to climb.
Scapulas (shoulder blades) on the side, with long horizontal clavicles which place the humerus facing forward. This forward facing humerus enhances the primate's ability to climb in a posture with its forelimb above its head.

Primate Skull Features

Being able to identify and compare different parts of a primate skull can help to identify the type of primate and various aspects of its biology (e.g. diet).

Knowing the names of major skull bones, as well as the features associated with a modern human skull will help you identify some of the evolutionary 'landmarks' in the development of humans.

For each of the male gorilla and modern human skulls below, you will use the internet to label each feature.