Bio Anth Midterm 2

Primates as mammals

traits uniting / unique to primates | survey of primate taxonomy & diversity

Apes as primates

traits uniting apes | relationships among the apes | ape distribution and diversity

3 major groups of mammals

(phylogeny clear – shared reproductive mechanisms)

how many orders of placental mammals

20 orders of placental mammals

Primate diversity

Body size | Habitat | Social structure and mating systems | Diet | Activity cycle

Diet

Frugivorous | Folivorous | Faunivorous | Gumnivorous | Specialized | Omnivorous

Activity cycle

Nocturnal | Diurnal | Cathemeral

Unique primate traits

Some shared, derived primate traits: | binocular vision | color vision (red-green) | shortened snout | grasping hands & feet w/ rotating forearm! | Nails instead of claws | large brains relative to body size | extended juvenile period

Suborder Stepsirhini

Ancestral mammalian traits: Sense of smell is comparatively well developed (for a primate) | Eye has a tapetum lucidum (eye shine) | Most are nocturnal |

Derived traits: Grooming claw on 2nd digit of hind limb | Tooth comb | Postorbital bar

Strepsirhines

bony ring (“bar”) around the eye

Haplorhines

complete closure around the eye

Most non-primates

no bony protection around the eye

Lemurs (a kind of strepsirhini)

restricted to Madagascar

| Extremely diverse: nocturnal, diurnal, cathemeral | Varied diets: fruits, flowers, leaves, insects |

Also have varied social systems: large groups, solitary, monogamous pairs

Lorises and Galagos (strepsirhini)

Asia and Africa | All nocturnal | Varied diets - fruits, flowers, leaves, gums, insects, small mammals & birds | Social system: many are solitary or in pairs | Difference is how they move around:

Galagos (africa)

Known for their leaping abilities | Vertical clinging and leaping

Loris, potto (asia, africa)

Slow quadrupedal locomotion; | Strong, wide grasp

Haplorhines: Tarsiers, Monkeys, Apes

Derived traits: Almost all are diurnal | All lack the tapetum lucidum | Reduced olfaction, enhanced vision | Full postorbital closure (eye is fully encased in bone on the sides within the skull) | Larger relative brain size | Longer developmental periods

Tarsiers (haplorphines)

SE Asia |

Strepsirhine-like traits: | Grooming claw | Nocturnal | Small social groups |

Haplorrhine traits: | No tapetum lucidum | No tooth comb | More similar to monkeys and apes than to lemurs and lorises |

Derived traits | Adaptations for vertical clinging & leaping | Nocturnal predators of small vertebrates –faunivorous | very large eyes relative to body size

“Monkeys:”

Platyrrhines (aka new world monkeys / monkeys of the americas) |

Cercopithecoids (aka old world monkeys / monkeys of africa & asia) |

All monkeys: quadrupedal | Hind limbs and forelimbs of near equal length | Arboreal species have long tails to aid in balance on top of branches | Shoulder blade positioned to the side of the ribcage |

Note: monkeys of africa & asia are more closely related to humans / apes than to Monkeys of the Americas!

Monkeys of the Americas (New World Monkeys), Platyrrhines

South and central america | All are arboreal | Some have prehensile tails (tails that can grab on trees and kinda act like a fifth limb) | All are diurnal except Aotus

Small bodied (< 1kg) | Omnivorous, insects & plant exudates (gums) |

Variety of social grouping patterns: | Usually only one breeding female | But one or more breeding males (monogamy, polyandry) | Twinning is common | Males are principal caregivers

Aotus - the Owl Monkey

the only nocturnal monkey!

Capuchins, platyrrhines (New World Monkeys)

tool use, large brains, easy to train

Golden Faced Saki (New World Monkeys)

dental specializations for eating hard nuts and seeds

Spider Monkey (New World Monkeys)

prehensile tails; highly suspensory

Monkeys of Africa & Asia (Old World Monkeys)

Colobines vs. Cercopithecines

Colobines (Old World Monkeys)

specialized diet - mostly leaves! | Teeth and stomach specialized for this leave-heavy diet

Cercopithecines (Old World Monkeys)

dietary omnivores, so less specialized teeth, stomach
Cheek Pouches: cheek skin can expand to hold a lot of food

• Sexual swelling: female’s reproductive organs swell and get red roughly coincides with ovulation

Cheek Pouches

cheek skin can expand to hold a lot of food

Sexual swelling

female’s reproductive organs swell and get red roughly coincides with ovulation

Apes

five different groups of apes

Apes have no tail | Relatively large brains and enhanced cognition | Prolonged development | Postcranial adaptations for suspensory posture and locomotion | Short hindlimbs, elongated forelimbs | Mobile shoulder joint | Long and curved fingers for grasping branches |

Gibbons and siamangs | Orangutans

African Apes

• Gorillas (genus name: Gorilla) 

• Chimpanzees and bonobos (genus name: Pan)

  • Knuckle-walking: form of quadrupedalism practiced by gorillas, chimps, and bonobos

    • Wrist joints are stabilized

  • Chimps and bonobos are more closely related to humans than they are to gorillas

• Humans (genus name: Homo)