Anthropology - Primates 3304 - Exam 1

What is the intermembral index? What’s the formula? What does the results indicate?

It helps compare limb proportions to understand locomotor adaptations.

The formula is Humerus+Radius/Femur+Tibia X 100

#>100 = arms are longer than legs - brachiation

#<100 = legs longer than arms - leapers

What are primates?

They are an order of mammals that are eutherian

What was one of the first primates?

Eomaia

What is the post cranial features of primates?

• grasping hands and feet (prehensility)

• nails instead of claws

• flexible limb structure

• erect (orthograde)

• Diverse locomotion

  • arboreal quadrupedalism

  • terrestrial quadrupedalism

  • brachiation

  • leaping

  • bipedalism

what are the five locomotion to remember from primates and describe how they walk and where they live in the forest.

• arboreal quadrupedalism

  • walking or running on all fours

  • lives in forest canopy

  • long tail

• terrestrial quadrupedalism

  • walks or running on all fours

  • lives in terrestrial areas

  • short tail

• brachiation

  • very long arms

  • lives in forest canopy

  • swinging between branches with their arms

• leaping

  • leaps between trees

  • lives in forest canopy

  • very long strong legs

• bipedalism

  • walks on two hindlimbs

  • long lower limbs

  • terrestrial areas

what habitats do most primates live in?

Tropical arboreal

What are the craniodental features of primates?

• Reduced olfaction, enhanced vision

  • forward facing eyes

• Heterodonty, 2123 dental formula

• large brains due to being omnivores

• Post orbital bar

• petrosal bulla

What gender invest more in the reproductive process?

females

What do males compete for and what are the five ways they do it?

they compete for females

• physical

• sperm competition

• infanticide

• pecking orders

• females choice

Primates have group living. What are the costs? What are the benefits?

Benefits:

• increased protections from predators

Costs:

• increased competition for resources

What determines the female distribution across a landscape? What are they most concerned with finding?

Access to food

What are the social organizations and which is more primitive?

• monogamous

• polygyny (one male, multiple females)

• Polygynandry (multimale, multifemale)

• Noyau (foraging subgroups)

• Polyandry (multimale, one female

MOST PRIMITIVE: NOYAU

What is heterodonty? what is the formula?

having various different types of teeth

higher primates: 2123

Describe the diets (FLIESMO)

F(ruit)- frugivores

L(eaves)- folivores

I(nsects)- insectivores

E(xudate)- gummivores

S(eeds)- granivore

M(eat)- carnivore

O - omnivore

What diet do most primates have and why?

They have omnivorous diets - the larger the brain the more need for a diverse diet

List the diets and the type of teeth that correlates

F(ruit)- frugivores

• broad incisors, flat molars

L(eaves)- folivores

• small incisors, high shearing crest on molars

I(nsects)- insectivores

• small incisors, high shearing crests on molars

E(xudate)- gummivores

• forward tilted tooth comb

S(eeds)- granivore

• flat strong thick molars

M(eat)- carnivore

• sharp canines for tearing meat, omnivorous molars

O - omnivore

• diverse set of teeth, generalized teeth

What is knuckle walking and why did it evolve?

trees and ground mechanism in which apes can keep their long fingers for trees but can also allow for walking on the ground

• it is energy sufficient

• as walking became more common, they needed a way to walk without damaging their fingers

Diet and brain size - why do folivores have small brains and frugivores have big brains?

folivore - don’t need to map out their food source, it is very abundant

frugivore - needs to map out mentally their foo source, not that abundant

What is the reproductive and life span history of primates?

• longer gestation period

• single offspring = infants are nourished better

• longer time between births

• extended care by the mother, usually until 8 years old

• diverse mating systems

• longer lifespan

What are the lower primates called and what are the three groups? of the three, one group has two other categories, what are they?

The lower primates are called prosimians

• lorisiformes

  • bush babies (galago’s)

  • lorises

• lemurs

• tarsiers

Where do the galagos live verses the lorises?

Galagos - africa ony

lorises - africa and asia

Where do the lemurs live?

only Madagascar

How are prosimians primates?

They have the minimum requirements for being a primate

What are the minimum requirements for being a prosimian?

• retained primitive features

• lack advanced features

• reliance on smell

• jacobson’s organ

• rhinarium

• post orbital bar ONLY

• smaller brains

• laterally facing orbits

• tooth comb

• noyau system

What are the features of galagos?

primitive features

• small bodied

• nocturnal

• olfaction very important

• noyau social system

• high degree insectivory

What are the features of lorises?

• laterally directed orbits

• postorbital bar ONLY

• unfused mandible and frontal bone

• toothcomb

What do the glands and teeth on a loris mimic?

the cobra

What are the five prosimian families?

Lemuridae, Indriidae, Cheirogaleidae, Lepilemuridae, and Daubentonidae

Are there any anthropoids on Madagascar, why?

Madagascar consists almost entirely of prosimians, specifically lemurs

isolation kept anthropoids away from Madagascar

What is an indriid unique feature? Why?

2023 dental formula

VCL

Why is Madagascar falling apart? What happened to the animals?

Human activity/hunting, geological effects like erosion

Features of the aye-aye

related to lemurs

nocturnal

rodent like incisors to dig in wood

long middle claw that rotates 360 degrees to percuss on wood

large eyes

huge bat like ears to hear insects inside wood

What classification splits tarsiers?

Strepsirrhine and haplorrhines

• features that tarsiers and anthropoids share

• features that tarsiers and prosimians share

• features that are unique to the tarsier

tarsiers → anthropoids: no rhinarium, mostly enclosed post orbital plate, fused upper lip, no tapetum lucidum, same pathway with internal carotid

tarsiers → prosimians: grooming claw, unfused mandible, small body size, nocturnal, VCL

tarsiers → unique: eyes bigger than brain, neck rotation, fused tibia and fibula, lowest intermembral index, infant parking, only totally insect eating primate

What are the circulation differences between lorisiforms, lemurs, and tarsiers

Lorisiforms: internal carotid forms into the ascending pharyngeal

Lemur: internal carotid forms into the stapedial branch

Tarsier + Anthropoids: internal carotid forms into the promontory branch

What is the importance of moonlight for tarsiers?

Their hunting and foraging increased when there is a full moon

Who coined the term primates?

Carl Linneus

What primates diverged much from their ancestors?

No, they lack specialization

Primate definition

1. orthograde

2. flexible and generalized limb structure - radius and ulna are infused; tibia and fibula are infused; allowing them to live in the trees

3. prehensility- hand and feet have a high degree of grasping abilities; retention of 5 digits, opposable thumbs, nails not claws, high sensitivity in tactile pads

4. face - reduce snout and rotated eye orbits; less reliable on smell and more on sight
   skulls - post orbital bar

5. brain size - significantly large for their body size

6. heterodonty - dental formula (2-1-2-3)

7. special senses - expanded/sophisticated brain, binocular vision, color vision

How do females compete for men?

intersexual selection: choosing based on features

personality traits: being more personable

What is the bachelor group in primates?

mature, non-dominant males who are not part of a breeding group.

Suspension 1, 2, 3, 4

1) arms winging, hook hands

2) feet are second hands

3) tail is a third hand

4) bipedality

Most likely candidate for primate ancestors

plesiadapoforme

Where are tarsiers found?

SE Asia

What is kays threshold?

primates above 500 grams are too large to get their protein from just insects alone