Primates Flashcards
Who are the primates?
- 350+ species
- 11 genera are extinct
- Origin approx 65mya
Diversity
- Body size
- Locomotion
- Feeding
- Reproduction
Grasping hands and feet
• Five digits on each hand and foot
• Flat nails and sensitive areas on the
ends of their digits
• The first digits are opposable
Types of Primate
Haplorhines : - New World Monkeys - Old World Monkeys - Asian Apes - African Apes - Hominids and Strepsirrhines
Less reliance on smell, more on vision
binocular vision -> stereoscopic 3D
some of us have colour vision, why?
• Fruit vs sexual swellings
Encephalization quotient
Large brain relative to body size
Complex social organization
Living in permanent groups – approx. 70% primate genera – approx. 20% other mammals 1. single female and her offspring 2. one-male-several-female group 3. monogamous family group 4. multimale-multifemale group 5. polyandrous family group 6. fission-fusion society
Strepsirhini
• “wet-nosed” • Characteristics – Large eyes & ears – Only primates to primarily rely on smell for hunting and social interaction • Examples – Lemurs – Aye-ayes – Lorises
Haplorhini
• “dry-nosed”
• Larger and more diverse category, broken up into 3 main groups
– Anthropoids
• catarrhines (Old World monkeys and apes)
• platyrrhines (New World monkeys)
– Tarsiers?
– (extinct) Omomyids
Primate life histories
- Long gestation periods
- Small lipers
- Large neonates
- Slow post-natal growth
- Late age at first reproduction
- Long lives as compared to other mammals of similar body weight.
Why slow life histories?
- Learning to acquire skills, knowledge
- Big brains and long lives- interconnected features of primates
- Brain expensive organ, slower physical growth as a trade-off
Why larger brains in primates?
- Social intelligence hypothesis-benefits of group living -> requires computational power
- Due to feeding niche, or fruit in scarce and patchy areas? Need memory and planning!
- Or methods for extracting foods? Nuts, digging, insects through tool use..
Theory of mind
The ability to atribute mental states (intentions, emotions) to others (e.g. what someone might be thinking about what you think).
• Essential to form strong, lasting social bonds
• In human children theory of mind (ToM) typically develops around age -3-5 years.
• Children with Down’s syndrome, but many with autism not seen ToM at this stage
• Disputed what species have exhibited