Primate Evolution

Question 1

What are primates?

Answer 1

Members of the order primates, all share common characteristics but there are differences between them e.g. New world monkeys, old world monkeys, great apes

Question 2

What are the sources of evidence for primate evolution?

Answer 2

1. Comparative anatomy of the primates
2. Comparative biochemistry
3. Behaviour of living primates
4. Fossils of primates

Question 3

What are Hominids?

Answer 3

• Classified under ‘Family’
• Hominidae’
• Includes all modern and distinct orang utans, gorillas, chimpanzees, all great apes and humans

Question 4

What are Homines?

Answer 4

• Classified under ‘Sub Family’
• Include all modern and extinct chimpanzees and humans
• ‘Hominae’

Question 5

What are Hominins?

Answer 5

• Classified under ‘ Tribe’
• ‘Homini’
• Include all extinct ancestors of humans and modern humans

Question 6

What are Homo’s?

Answer 6

• Classified under ‘Genus’
• ‘Homo’
• Include some extinct ancestors of humans and modern humans

Question 7

What are Homo Sapiens?

Answer 7

• Classified under ‘Species’
• ‘Homo Sapiens’
• Modern Humans

Question 8

What are the types of Primates?

Answer 8

• Lower Primates (Non Tarsier Prosimians)
• Tarsiers
• Higher Primates

Question 9

What are Lower Primates?

Answer 9

• Non Tarsier Prosimians
• Include: Loris, Aye Aye, Indri, Lemurs
• All have large tails

Question 10

What are Tarsiers?

Answer 10

Big eyed, nocturnal

Question 11

What are Higher Primates?

Answer 11

• New World Monkeys (Tamarins, Marmosets, Capuchins, squirrel monkey, spider monkey)
• Old World Monkeys (Rhesus monkey, Baboon, Langur)
• Lesser Apes (siamang, gibbon)
• Greater Apes (orang utan, gorilla, chimpanzee)

Question 12

What are primate evolutionary trends?

Answer 12

-Digits, cerebral cortex, dentation & prognathism

Question 13

What are the differences between Great Apes and Humans in regards to Digits?

Answer 13

• Limbs in humans are unspecialised
• Are pentadacytl (5 digits) on hands and feet
• Highly mobile digits (due to ancient arboreal way of living)
• Grasping/ prehensile (digits are usually for climbing and wrapping around trees)
• Opposable thumb (can touch all 4 other digits) - due to increased length of first digit, opposable big toe was lost in humans when the human foot became a weight bearing appendage rather than a grasping one
• Humans have nails rather than claws e.g. Aye Aye
• Sense receptors on end of digits for grip and manipulating objects
• Friction ridges (finger prints) increase grip
• Short broader hands, short straight fingers, strong thumb, opposable thumb allows for grasping of objects
• PRECISION GRIP: used for holding pen, needle, pencil - movement between thumb and index finger allows for effective handling of small or delicate objects

Question 14

What are the differences between Great Apes and Humans in regards to the cerebral cortex?

Answer 14

• Cerebral cortex has increased in size
• Involved in higher order functions such as thinking, memory
• Being arboreal lead to accurate vision, tactile perception and better coordination between sensory organs and muscle response