primates Flashcards
General primate features
1) 250 species
2) restricted to tropical regions , mostly arboreal
3) mostly general omnivores, some specialised leaf eaters ( cellulose fermentation)
4) Earliest know true primate = 55 million years ago
What are the promisians
lemurs , bush babies etc .
- basic primates
- formerly combined with tree shrews
New world monkeys (ceboidea)
Marmosets, tamarins, spider monkeys
Old world monkeys (Cercopithecoidea)
Macaques, baboons, langurs
Apes, hominids, humans (Hominoidea)
1) lesser apes (Hylobatidae) - gibbons + siamang
2) great apes (pongidaes) - gorilla, orangutan, chimp, bonobos + humans
Primate characteristics
1) retention of clavicle (collar bone)
2) shoulder joints permitting limb movement in all directions + elbow joints
3) 5 digits on fore + hind limb
4) reduced snout
5) claws modified into flattened nails
6) large brain
7) most features present are attributed to arboreal lifestyle
Example of a “missing link” between promisians and simians
E.g. Darwinus Massilae -47 million years old
Strepsirrhini (wet nose) characteristics
- Tarsiers + promisians
1) usually small , nocturnal +long snouted
2) distributed across Africa and SE Asia
3) lemurs native to Madagascar , more diverse with large species
Characteristics of old world monkeys (catarrhine “narrow nosed”)
1) old world monkeys are more specialised + species rich than apes
2) two premolars
3) Colobines= Africa + Asia, folivores with complex fore-stomach (arboreal)
4) cercopithecinae= Africa ,omnivorous , increasingly terrestrial (baboons etc.)
Characteristics of new world monkeys, Platyrrhini and Cebidae “broad nosed”
1) 3 premolars (more primitive)
2) colonised S.America - across the atlantic
3) no radiation into terrestrial forms
- Cebines = squirrel monkey
- callitnchines = marmosets
- atelines = spider monkeys (prehensile tails)
Characteristics of Hominoidea
1) critically endangered
2) broad thorax and dorsal position of scapula (assists balance in bipedal pose)
3) caudal vertebrae reduced (usually no tail)
4) front skull characterised by sinuses
5) 5 cusps on molars (olw world = 4)
Go over social system in primates table
look at notes
Primate vision, what are the 3 types of colour vision
1) Dichromy (red/green colour blind)
2) Routine Trichromacy (new world)
- individuals of same sex + species can differ
- frequency dependant advantage
Colour vision in mammals
1) range from red -> violet
2) most mammals are colour blind
3) Colour vision is the ability of an organism to distinguish objects based on the wavelengths of the light they reflect , emit or transmit
How do cone cells help see colour
-cone cells in retina contain photopigments called opsins that “see” colour
