Primate Adaptations and Evolution Unit 2

Strepsirrhine Synapomorphic Traits

(shared traits that evolved after a split with other primates)

• grooming claw

  • compressed nail

• lower canine and incisors in a comb for grooming

• sloping fibular facet on talus

• ectotympanic ring

  • lemur floats free in bone, tambourine

  • loris fused to wall of bone

Strepsirrhine Symplesiomorphic Traits

(shared ancestral traits, retained primitive trait)

• post orbital bar

• small brain case

• primitive nasal region

  • well developed, long snout

• wet rhinarium

  • split nose

• multiple nipples

  • 6~

• tapetum lucidum

• bicornuate uterus

• epithelium as main transfer of nutrients?

  • less efficient than higher disk?

Lemuroids only in Madagascar

• broke off 100 million years ago

• lemurs came from loris that somehow made their way to Madagascar

• primate equivalent to Darwin Galapagos islands

  • species spreading out on island where they are isolated and evolve

  • no predators no competition

• huge radiation

• used to be all rainforest, central plateau now grassland, only coast has forest presurved

• only 26% remaining forrest

• 5 families of primates on Madagascar (5/14 primates)

• at least 15 genera

• superfamily lemuroidea

  • cheirogaleidae

  • lepilemuridae

  • lemuridae

  • indriidae

• superfamily daubentoniidae

  • daubentoniidae

Cheirogaleidae

• 30 species

• dwarf lemurs

• typical lemurs

• 2.1.3.3 dental formula

• ectotympanic ring in ear (classic)

• 3 pairs of nipples

• has twins/ triplets

• open 2nd forests

• mostly quadrupedal

• nocturnal

• diets vary insects, fruit, gum

• no real social structure

  • monogamous/ noyau

• cranial blood supply from ascending pharyngeal of external carotid (other lemurs supply come from internal) (same as mainland loris; tells us it is probably most primitive lemur)

fun facts

• smallest living primate

• weighs one ounce?

• sexually receptive 1 day out of the year

• Jacobson organ (smell) defect female reproductive time?

• fat tailed dwarf lemur (tails filled with fat)

Lepilemuridae

‘“sportive lemur”

• 26 species?

• larger than 500 gr - 1 kilo

  • just big enough to digest leaves

• 1 living genus

• noyau

• clingers and leapers

• leaf eaters

• active during day

facts

dental: 0.1.3.3/ 2.1.3.3

don’t kiss them on the lips because they reingest feces

Lemurids

• 22 species

• 2.1.3.3

• ectotympanic ring

• most are diurnal

• most live in large groups

• multi female multi male up to 32 individuals

• 1-4 kilos

• have twins

• most are arboreal quadrupeds

  • spend some time on the ground

• seasonal frugivores

• sexual 1 day of the year

specializations

U lemur: sexually dichromatic (different colors)

Bamboo lemur: eats bamboo, they have to detoxify during digestion

Indriids

• 3 genera

• folivores

• leapers

• reduced dental formula, 4 teeth

  • lost 2nd incisors or canine?

  • 2nd premolars??

• ring in tympanic…

• large stapedial artery

• monogamous

• single births

• up to 10 kilos

Daubentoniidae

• 1 living species

• large brain to body

• insect specialists

• long ever growing incisors (like rodent)

• super long middle finger

  • adaptations for digging out termites

• nail compressed into claw

• course hair like porcupine

• massive ears

• bushy tail

• solitary

• fully arboreal

• make large nests to sleep in at night

• 1 incisor, 3 small flat molar

• 1.0.0.3 dental formula, most bizzare

• folklore about them

• nocturnal? (but he said they sleep at night)

subfossil lemurs

• extinct non fossilized bones

• people on Madagascar were there 2000 years ago, hunted some lemurs to extinction

• people report seeing weird bones from archaeological sites

  • cut marks on bone: evidence for people eating them

• no fossil Cheirogaleidae

  • too small to hunt

subfossil lemurs Archaeolemur and Hadropithecus

“monkey lemurs” look like monkeys

Archaeolemur

• 20 kilos

• look like arboreal quadruped monkey

• used for human evolution, old world monkey convergence

• teeth look like “bilophodont”

  • similar teeth to large, terrestrial, grass eating monkey

Hadropithecus

• up to 30 kilos

  • larger than 50% of living primates

subfossil lemurs Palaeopropithecus

• sloth like

• long curved fingers and toes

• 50 kilos

• folivore

• extra bone in/on teeth, only seen on…? lips?

subfossil lemurs Megaladapis

• related to lepi lemurs

• 200 lbs

subfossil lemurs Archaeoindris

• like extinct giant ground sloth

• like largest living gorilla?

• 450 lbs

• no tail

• curved fingers and toes

• terrestrial

• ate trees? bush?

• molars support folivorious diet

Madagascar explosive adaptations

• natural selection

• biogeography

• few predators no competitors

  • until people show up

Strepsirhines of Africa and Asia

• in Sub Saharan Desert to Kalahari Desert

• rainforest to desert biomes

• lorisoids in south Asia, Southeast Asia, and indonesia archipelago

• tarsiers indonesia archipelago and Philippines

  narrower radiation than Madagascar

• more predators and humans

• more competitors

  • these narrow niches

Galagonidae

• bush babies

  • make a crying sound in bushes at night

• vary in size

  • 70 grams to 1.2 kilos

• 18+ species

• massive eyes

• big ears

  • can move them around

• longer legs than arms

• leapers

• ankel is elongated

  • helps with leaping

• limited to Sub Sahara Africa

• multiple species in one space

• very quick

contrasts with Lorisidae

Lorisidae

“potto”

• arboreal (dont leap)

• nocturnal

• slower and stealthy

• small ear

• short tail

• 12~ species, 4 genera

• limbs more equal in length

• more robust? not as slender

• 200-1500 grams

• Africa: Potto

• Asia: Loris

Lorisoids

• vary in diet

• vary in canopy height

• solitary foragers

• monophyletic group

Tarsiers

• most primitive of higher primates

• share traits with lower

• intermediate with lorisiformes and anthropoids?

• 12+ species, 3 genera

• all live in Indonesia and Philippines

• environment biomes vary

• nocturnal

• big eyes

• long legs

• derived traits with anthropoids

Tarsius

symplesiomorphic traits shared with strepsirhines

• unfused mandibular symphysis

• grooming claw on 2nd digit (or 3rd?)

• multiple nipples

• bicornuate uterus

synapomorphic traits shared with anthropoids

• retinal fovea

• partial postorbital closure

• no attached upper lip with median fold

• reduced nasal turbinates

• promontory branch of internal carotid artery to brain

• tympanic ring external to bulla? bony tube?

• large upper central incisors, small lower incisors, large canine

• hemochorial placentation, monthly estrus with swelling?

they demonstrate how evolution works

tarsius automorphic traits “unique”

• massive eyes, same size as brain

  • because they dont have tepedium lucida, they lost it

• clinging and leaping ability

  • femur, tibia, ankle bones same length

  • can leap 10 ft

• 50- 150 grams?

• big hands and feet

• diet mostly animals (insects, spiders, small vertebrates)

  • most faunivorous

• nayou/ monogamy with parental care

• territorial

• bicornuate uterus

• single births

  • 1 new born can weigh 30% of mother

Anthropoids

“higher primates” “new world”

haplorhine derived traits

• fused frontal bone

• postorbital closure

• lower brain

• lower incisors

  • trend to have larger central incisors upper, opposite for lower)

• most have nails, uncompressed

• most diurnal

• loss of stapedial artery

• blood supply to brain from promentory artery

• orbits face forward

• no tapetum lucidum

• have retinol fovea

• have colored vision

• tympanic ring (or 2) fused to bone

• tend to have larger more equal in length limbs

• no grooming claw

• platerhines retain both tympanic ring and tube

• primitive formula 2.1.3.3

• tambourine like?

Platyrrhine

• “flat” nose, flaring nose, broad

• 2.1.3.3.

• “I” shaped suture in skull

• prehensile tail

• North, Central, South America

• limited to Americas

• Yucatan down to tip of Argentina

• mostly tropical

• Only fossils in Norther

• arrived? in S. America 30 million years ago

traits of Plat as a whole

• small to medium size

  • 100 grams - 10 kg

• 3 premolars

• ectotympanic ring: tambourine like, floating

• parietal and zygomatic touch

• hole for nerves on humerus “entepicondylar foramen"“

  • ulnar nerve goes through hole, lack of funny bone nerve

secondary derived traits

“not present in their ancestors, but look more primative

Catarrhine

• “old world”

• nose points down, narrow

• all have butt pads (covered in keratin)

  • shared with tarsiers unique derived

• 2.1.2.3

• “H” shaped suture in skull

• cheek patches

• tubular ectotympanic?

Callitrichines

• smallest new world monkey

• 2nd derived?

• nails compresses side to side, look like claw

• most simplified molars with only 3 cusps

  • lost hypocone

• most lost 3rd molar

• 2.1.3.2

Callimico (genus)

• most primitive

• retains small, hypocone

• 3rd molar retained, small

• short snout and brain case

• short limbs

• claw like nail

  • except big toe ‘tegulae’, allows for better clinging

• does not have twins

• 600g

• fruit eating

• lives in 2ndary forests

• monogamous with paternal care

Marmoset

• has twins

• less than 1kg, small as 100g and up to 750g

• paternal care for young

• monogamous/ polyandry

  • 1 female 2 male

• 50 species

• include smallest of higher primates

• large incisors, thin enamel

• gum specialists

  • also eat insects and fruit

• South America

• lives in the understory

• woodland to rainforests

• sleep in tree holes

Tamarins

“cotton top” “golden lion””emperor tamarins”

• long arms webbed hands

• larger than 350g-800g

• long trunk, tail, legs

• quadrupeds

• has twins

• paternal care

• South and Central America, up to Panama

• not gum specialist

• eats mostly insects, little fruit

• sleeps in tree holes

• monogamous

  • 1 male multi female sometimes

• 24 species

Aotinae

“owl monkey” “night monkey” “douacou”

• 1 genus, 11 species

• only nocturnal anthropoids

• 1 kg

• long legs, long tail

• pads on digits, slightly opposable thumbs

• compressed nail on 4th digit

• large eyes: rod and cone fovea

  • evolved from diurnal platyrrhines

• throughout S America

• quadruped with some leaping

• frugivores with insect and leaf supplementation

• monogamous

• they howl

• annual single births

• paternal care

Cebines

‘capuchins’ ‘squirrel monkey’

• 3 genera, 7 species

• Saimiri- squirrel monkey <1 kg

• long occipital and foramen magnum

• sharp crested molars

• frugivore and insectivorous

• long tail, prehensile tail in infants

• short fingers, not opposable thumbs

• prefer riverine and secondary forests

• leaping arboreal quadrupeds

• groups 12-100

• female hierarchy

• no infant care from males

Cebus/ Sapajus

‘capuchin/ organ- grinders?

• 22 species

• 2-4 kg

• groups of 15

• thick molar for crushing nuts

• S and Central America

• some eat fruit and insect supplementation

• prefer main canopy levels, will come to ground

• arboreal quadrupeds

• prehensile tail

Allouatine

‘howler monkey’

• 1 geneus, Alouatta, 12 species

• broadest distribution of S American primates

• Southern Mexico to N Argentina

• 4-12 kg

• sexually dimorphic

• prehensile tail

• small incisors, cresty molars

• small brain

• large deep mandible

• folivorous with some fruit

• arboreal quadrupeds, slow

• tropical rainforest to open woodland

• prefer main canopy when possible, goes on ground to pass through tree patches

• 1 male multi female

• 12-30 in a group

Atelinae subfamily

‘wooly’ ‘spider monkey’

• 14 species, 3 genera

Ateles

• spider monkey, 7 species

• from Yucatan through Amazonia

• montane and tropical forest

• prefer upper canopy

• 7.3- 9.4 kg

• long limbs, slender, for suspension

• prehensile tail

• long hands and feet, no external thumb

• brachiation and arboreal quadruped

• no sexual dimorphism

• mostly frugivores, some leaf supplementation

• fission fusion

Brachyteles- muriqui

• 2 species

• 8-9.6 kg, sometimes larger?

• Brazilian rainforest, high in tall trees

• long limbs, no thumbs

• arboreal quadruped qith suspensory

• cresty molars

• frugivorous and folivores

• multi male multi female

  • lots of promiscuity

Lagothrix- wooly monkey

• 5 species

• amazon tropical rainforest, all canopy levels

• sexually dimophisms

• 4.5-7.3 kg

• prehensile tail

• non opposable thumb

• mostly frugivore with some leaf

• multi male multi female

• restricted to high rainforests

• arboreal quadrupeds

Callicebinae

titi monkey

• 0.8-1.3 kg

• 1 genus Callicebus 30 species

• primitive cebids, short faces, fluffy tails, long legs, short canines

• S America

• canopy levels vary

• river lined forests

• quadruped and leaping

• frugivores with leaf and insect supplementation

• single births young carried by male

• monogamous

Subfamily Pitheciidae

• 3 genera, 13 species

• 1.5-4.5 kg

• dental specialization large procumbent incisors, robust canines, low cusp molars, prognathic snout, enlarged nasal bone

• quadruped with some leaping

• fission fusion group, small group forage sometimes multi male groups single births, no paternal care

pithecia

• 5 species

• 2 kg

• gracile skull and jaw

• long trunk and long legs

• mostly from Amazon also Guianas

• lower canopy, forest preference varies

• fruit seed predators? crush hard fruit seeds

• monogamous fission fusion

Chiropotes- bearded sakis

• 3 kg, more robust skull and jaw

• Prefer high rainforest, middle/upper canopy

• Arboreal quadrupeds, hindlimb suspension

• Feed on hard, unripe fruits and seeds

  • Some insects

• Large multimale multifemale fission-fusion

Cacajao- Uakaris

• 3-4.5 kg, short tails, northern South America

• Quadrupedal walkers and runners

• Prefer flooded rainforest

  • All levels of rainforest except ground

• Large social groups up to 50 animals

• Mostly frugivorous

  • Procumbent lower Is & big canines

• Grotesque in appearance

radiation

• arrived on island continent long ago, 30 million ya

• no competition with other primates

• no extent radiation: up tp 13 sympatric primates at a time

  • manu great differentiation

• good variability within the infraorder

• small to medium sized animals, 100 g- 10 + kg

• all are diurnal, except Aotus

• locomotion/ positional behaviors specializations

• generally subequal limb lengths

• mostly arboreal quadruped

• very few come to ground often, none fully terrestrial

• some are good leapers and other suspensory

• some cling well with claw-like nails

• some have evolved the bizarre prehensile tail

• gambut including leaves, fruit, unsects, gum, nectar?

some organization variable

• some monogamous, others large multi male multi female groups

• some chimp like fission fusion, some polyandry/ polygamy

• some single births, others twins

• some paternal care

• phylogenetic relationships

Molecular studies 

• 3 clades, pitheciidae, atelids, cebidae

• pitheciidae are the sister taxon to two other groups

• within pitheciidae, callicebus are sister to pithecine

• among the atelids, alouttines are sister to atelines

• bizarre fallouts of new molecular phylogenies

• Aotus linked with cebines and callitrichines rather than cellicebus

• night and titi similar in anatomy

• maybe shows share traits are primitive

• placement of Callimico within Callitrine clade suggests loss of 3rd molar with twin births evolved independently

Infraorder Catarrhine

• Superfamily Cercopithecoidea

• only one family Cercopithecidae

  • Cercopithecinae

  • Colobinae

• prehensile tail

• cheek pouches

• Craniodental

  • Cercopithecidae: have narrow elongated snout

  • Hominoids: wide snout

• Hominoids have larger brains relatively larger for skull size

• teeth:

  • cer: look bi thelodont “bread like”, separated by waisting, dagger like canines

  • hom: upper has 4 cusps not waited, lower has five cusps, fisher pattern forms Y, stubby thicker canines

• tail:

  • cer: has tail, mostly arboreal all quadruped with long trunk

  • hom: all suspensory, with long arms and short trunk

• ulna:

  • cer: elongated olecranon process

  • hom: hook shaped

Cercopithecidae

-Cercopithecidae

-Colobinae

• teeth:

  • Cercopithecidae: narrow incisors

  • Colobinae: broad incisors, hucking fruit, elongated

• Jaw:

  • Cercopithecidae: narrower jaw: soft foods

  • Colobinae: deeper jaw: strength against vertical forces, tough foods

• har food requires large muscles, hard is difficult to initiated crack in tooth but brittle

• tough food is fibrous, needs repetitive loading and cumulative forces, each chew is not as forceful, tough food makes it difficult to spread a crack

• teeth shape:

  • Cer: high sharp cusps

  • Colo: flat blunt

• stomach:

  • Colo: complex multi chamber stomach that digests cellulose (microorganism bacteria) break down into glucose, but this limits diet, too much sugar causes bacteria to produce

• cheek pouches

  • cer: storages food

• Hands:

  • cer: shorter thumbs

  • colo: longer thumbs: manipulate food

cer: longer forelimbs

colo: longer tails and hindlimbs to leap

• location:

  • cer: mainly Africa, 1 genus outside in Asia

  • colo: Mainly Asia, fewer in Africa

• body mass:

  • cer: larger range 1kg-50kg

  • colo: narrower 4-20kg

Macaques

• 22 species, lots of variation

• widest distribution of nonhuman primates

• weed tactic, survive and thrive everywhere

• in 1 place in Europe, mostly in Middle East, India, SE Asia up to Japan (seasonal mountains snow)

• desert to tropical rainforest and to snow mountain

• opportunistic omnivore ‘more levels of food pyramid’

• eats mostly fruit

• 3-15kg middle size

• short fingers and opposable fingers and toes

• long snout

• low crowned molar cusps

• thin limbs

• arboreal quadrupeds

• spends time on groun

• in large groups 50+

• long tail

• lowland 2nd ary forest near river

• elaborate male/female hierarchy

• multi male multi females

• protects any kids, some genetic investment

• male exogamy

  • males leave group to avoid incest

Mangabeys

• 5-10 kg

• 2 forms

  • lophocebus and cercocebus

  • both adapted for hard object

  • thick molar, flat teeth, heavy jaw, big mastication muscles

• lophocebus:

  • consume hard object when there are no soft object

  • kabali forest, Uganda

  • look and act like wimpy, red tail monkey

  • prefer soft foods but adapted for hard object

• one species usually out competes other species

  • during drought they switches to nuts/ pits, survived; hard food as ‘fallback adaptation’

Liem’s Paradox

animals with anatomical specializations can behave as generalists “extreme generalists with fallback”

Cercocebus

• West and Central Africa

• mostly terrestrial?

• prefer hard foods, nuts

• black to gray color

• 5-10 kg

• 10-20 individuals in a group

• coexist without competition

• 1 male multi female

• primary forest

Guenons

• tamarins of Old World Monkeys

• 3 dozen species

• 1kg-10kg

Cercopithecus/ Allochrocebus

• 2 dozen species

• colors differ

• arboreal quadruped, some leaping

• different heights in canopy

• frugivores

• social organization differs

• 1/ multi male 1 female

Vervet

• 3-6 kg

• spends time on ground

• forest outside savanas

• supplement diet with insects or seeds

Patas

• 5-10kg

• massive home ranges

• fastest primates

  • 35 kmph

• grass seed, insects, lizard

  • vary open diet

• 1 male multi female

• male displacement

Swamp Monkey

• prefers closed swamp

• frugivore

• arboreal quadruped

Talapoins

• 1 kg, smallest catharines

• up to 150 in a group

• forests

• West Central Africa

• most insectivores of primates

• also east fruit

Baboon

• 10-30 kg

  • 25-100 lbs

• extreme sexually dimorphic

• females almost half size

• violent

• males protect group

• massive canines

• Savanas, Sub Sahara desert to down?

• terrestrial quadruped

• sleeps in trees

• move around a lot

• frugivores, leaves, grass seed

• will hunt when there are droughts or hungry

• used as model for human evolution

  • leaving trees for food

• multi male multi female

  • some 1 male multi female

• up to 150 in group

Geladas

• highlands of Ethiopia

  • rocky and poor vegetation

• red patterns on chest

• not as large canines

• most terrestrial non human primates?

• males larger than females

• 10-20 kg

• do not sleep in trees

• specialize eat grass seeds and blade?

• 1 male multi female and fission fusion

• can form herds of up to 3/400

• they bark

Drills and Mandrills

Mandrills: red, white, blue snout

• forest grounds

• males 30 kg

• females 10 kg

• females spend more time in trees

• eat fruit that has fallen on ground

• 1 male multi female

• will get into hers up to 150 when lots of resources are available, safety in numbers

• Western Central Africa

Colobinae

• narrow incisors, thick jaw, sharp crusty teeth

• complex multi chambered stomach

• shorter arms than legs

• shorter thumbs

• long tails

African Colobus Monkey

• 2 groups: black and white, red olive \largest of African Colobines

• 7-10 kg

• forests Sub Sahara

• arboreal quadruped with leaping ability

• various heights in canopy

• black and white come to ground less compared to red olive

• b&w prefer mature leaves: extreme folivores

• RO prefer immature leaves

• RO multi male multi female

• b&w 1 male multi female

Langurs/ leaf monkeys

• 3 types

  • spectacles, banded, sacred

• all prefer forest

• all infanticide

• sacred:

  • tropical to desert

  • South Asia

  • India, Nepal, Sri Lanka

  • 1 to multi male, varies

  • immature leaves

  • also flowers

• banded SE Asia

  • 6 kg smaller

  • arboreal quadruped with some leaping

  • immature leaves

  • 1 male multi female

  • females protect group

• spectacles eats more mature leaves, specialization

  • 12 kg

Odd Nose Monkey

Proboscis ‘trunk’

• monogamous

• lots of leaping

• swmaps… Indonesia

• immature leaves

• males 20 kg

• females 10 kg

Snub Nosed

• SE Asia, up to China?

Golden

• immature leaves and flowers

• 1 male multi female but also multi male?

Adaptive radiation of the Old World Monkeys

• competition and predation halt radiation

• 1-50 kg

• all diurnal

• all quadrupeds, some arboreal some terrestrial

• diets vary

  • no insectivores, some supplement

  • no gum

  • some hard object

  • some folivores

  • most soft fruita

• 1 male 1+ female, multi male

superfamily Hominoidea (cladistic tax)

family Hylobatidae

family Hominidae

-subfamily Ponginae (orangutan) (Asia)

-subfamily Homininae (african ape)

—tribe Gorillni (gorilla)

—tibe Hominini

—-subtribe Pinina (chimps, bonobos)

—- subtribe Hominina (humans)

Flegel’s tax

lesser hylobatidae (gibbon)

ponginae (grate apes)

-orangutan

-chimp

-gorilla

hominidae (human)

---

cant use this

not monophyletic

meansnot all …

halphy… all descents are included

Hominids vs Cercopithecoids

share:?

• 2.1.2.3

• excto tympanic tube

• skull suture pattern

Hominids:

• larger brain

• small legs and long arms

• short trunk

• 5 cusps, separate hypoconulid

• stubby canines

• suspensory

Cercopithecoids:

• broader skull

• 4 cusps

• long and think canines

• olecranon process larger

• long tails

• Arboreal quadruped, on group a lot

ape distribution

gibbons: broad, SE Asia mainland and islands

orangutan: islands of Sumatra, Indonesia, Malaysia

chimps: Sierra Leone, Tanzania… Congo Basin, more borad rainforest

bonobos:

gorilla: W Africa lowlands, Cen. African mountain?

Hylobatids: gibbons and siamangs

• 4 genera, 20 species

• most diverse

• SE Asia, India-China

• all highly endangered

• smallest of the apes

• 5-12 kg

• 3 groups of gibbons

  • lar group: smallest

  • concolor: middle

  • siamangs: largest

• often live together

• no sexual dimorphisms

• monogamous

• prefer small high energy fruit

  • siamangs eat more leaves over fruit, allows to live in the same patches of trees bc of different diets

• most primitive dentally

• long arms

• sully suspensory, brachiation: like Tarzan

  • highly specialized

• also leap 15 kmph

• massive home ranges bc they eat berries, terminal branch feeders

• go to bed at 3, high energy, cant maintain energy till sunset

• primary forests

• 2-3 km home ranges

• siamangs smaller ranges, don’t need to move as fast and stay up later

• don’t build nests

Orangutan

“people of the forest”

• Sumatra, Indonesia

• Asia great ape

• 2/3 species

• endangered

• used to be in mainland SE Asia now limited

• primary forests

• teeth have bumps ‘crenulations’ thick enamel and grind?

• suspensory

• make trees lean to swing to next tree

• males spend more time on ground

• long calls to defend, identify, and call mates

• large home ranges\males 10 sq km

• diet 60% fruit, some hard foods like bark and nuts, some leaves (males) insects (females), rarley hunt

• manufacture tools for getting into fruits and hitting wasps

• nayou traditionally thought?

• males on their own, babies stay with females

• exploded polygamy

  • alpha males, subordinate males, females and offspring

• sexual maturity 6-8 years

• males stay with moms longer than females do

• live 50-60 years

• subordinate males don’t grow cheek phanges, hormone triggers it in alpha males

Gorilla

• 3 species

• some in W Africa subforest and SE Asia mountains

• largest of living primates

• males 200 kg

• females 70-90 kg

• come to ground more frequently than other apes

• females and young spend more time in trees

• high crested teeth

• complex gut to digest leaves, terrestrial herbaceous vegetation ‘wild celery’?

• lower altitudes eat more fruit?

• will travel for fruit

• prefer fruits even though teeth…

• terrestrial quadruped, knuckle walk on ground

• will swing

• 12 in a group usually

• 1 alpha male, silver back

• female exogamy

• smaller day ranges: ½ km

• ones that live in lowlands are more skittish

• 1 male multi female

Chimps

• 4 subspecies

• troglodytes (common)

• paniscus (bonobo)

• Senegal to Tanzania

• savana woodland to tropical rainforest

• 30-60 kg

• moderate sexual dimorphism

• quadruped knuckle walk on ground

• high in canopy

• suspensory, semi brachiation in trees

• flexible opportunistic feeders

• insects: termites, will make stick tools to eat them

• tools also for opening fruit

• prefer fruits, supplement with leaves, vertebrates

• hunting done by males when female in estrus

  • maybe to have more access to females

• fission fusion

• female exogamy

• lots of inter male violence

• ‘chimp wars’

• common ape more aggressive

• can live 50-60 years

Bonobo

• 30-45 kg

• darker faces from youth into adult

• more hair on hed

• only Central Africa

• tropical closed canopy rainforest

• spend time on two legs

• mostly eat fruit

  • less vertebrate meat than chimps

• fission fusion

• female hierarchy, group dynamics run by females

• group tension solved with orgasms

• more peaceful and relaxed

Humans

• most broadly distributed, most distinctive

• heads out of proportion to body

• 14 cubic cm? huge brain

• external chin

• arms similar to chimp ?

• legs out of proportion, long, bu pedal, knock knee

• toes in feet aligned

• patchy hair distribution

• diet extremely adaptable

• geographic distribution linked to large diet ranges

• only primates to cook and have meals

• sweat and oil glands on skin

• bizarre distribution of fat between males and females

• usually monogamous

Adaptive radiation of apes

• adaptable opportunistic eaters

• prefer fruits but will have supplementation

• female exogamy

• social structure varies

• mostly suspensory, quadruped terrestrial, humans bipedal, knuckle walk, swing

• all diurnal

• 7- 200 kg

comparative approach to reconstruct diet in fossil record

diet most important to social organization

if there is a clear link between anatomy and behavior it probably stayed the same, if it worked, parsimony

uniformitarianism: forces at work in the past are the same today

body size allometry:

• study how body size impacts behavior and anatomy

• metabolism and energy burn

• smaller body needs more energy to keep itself warm

thermal inertia: something thats bigger will retain heat better

endotherms: we create our own body heat (mammals)

ratio of surface area to volume

inertia: force or energy to change states

Rich Kay’s Threshold

in under 1 kg you cant eat leaves

if over 1 kg you cant eat eat insects

-has to do with capture rates

smaller cant extract energy from leaves bc gut is too short (leaves cellulose takes time to break down)

size vs crests and diet

larger with high crests: leaves and fruit

larger with lower crests: fruit

smaller with high crests: insects and fruit

smaller with lower crests: fruit

common lines of evidence

evidence of adaptation

(what you inherent)

1. tooth size

2. tooth shape

3. tooth structure

evidence of function (food prints)

(what you eat in daily basis)

1. tooth wear

2. tooth chemistry

tooth size

assume bigger teeth the more it was used

bigger incisors for processing fruit

bigger molars for processing leaves

tooth shape and diet

colobines have cresty teeth

gorilla steep crests

orangutans middle

chimps lowest crests

tooth structure

how thick enamel is

thick: hard object eater

thin: fruit and leaf eater

prism structure of tooth

tooth wear

pits: ate hard objects

scratches: ate leaves

hard objects hit teeth

leaves sheer

Dental Topographic Analysis: dental microwear texture

anisotropy: highly aligned, scratches

complexity: surfaces from lots of different shapes, pits

tooth chemistry

isotopes

chemical traces in tooth from food you eat

C13 grasses

C12 tree and bush

these come from different ways of photosynthesis

uncommon lines of evidence

fossilized gut content

fossilized poo

bone composition: disease

-hyperuitamosis A

phytoliths embedded in tartar/ calculus

Locomotion

Smaller primates more likely arboreal

Cut off around 10kg~

Suspensory arms need to be long enough to reach between trees

All locomotion balance between flexibility and stability

• Arboreal quadruped

• Terrestrial quadruped

• Leaper

• Suspensory

• Biped

Arboreal quadruped

• Intermembral index: ratio of arm to leg length 

• 1:1 arms same length as legs

• Short limb lowers center of gravity, makes balancing easier

• Straight back

• Grasping hands and feet

• Shoulder and hips face downward, gives maximum stability 

• Enlarged epicondylar (on humerus) for grasping 

• Olecranon enlarged and steeper ankle for lower center of gravity 

• Long tail for balance

• Narrow thorax

Terrestrial quadruped

• Olecranon process rotated backward

• 1:1 ratio

• Long limbs to move quicker

• Short fingers and toes

• Restricted shoulder joint: stability

• Narrow thorax

Leapers

• Long legs to jump

  • Elongated femur, tibia, tarsal (i think)

• Long and curved fingers and toes

• Soda can shaped femoral head limits range of mobility to one way

• Long and bow chapped vertebrae, acts like a spring

Suspensory

• Long arms to reach further

• Short trunk: moves center of gravity

• Often no tail

• Mobile hip joint

• Long and curved fingers and toes

• Big medial epicondyle 

• Rotary wrist joint

• Short olecranon process, crescent shaped: flexibility 

• Board thorax

• Dorsally placed scapula

Biped

• Low intermembral index, long legs, long stride length

• S-shaped spine, transfers force

• Adducted knee: valgus, balances weight when switched weight between legs

• Adducted big toe: stability?

Other signals

• Wolff’s Law: bones respond to forces that are placed on it

• Osteoblasts create new bone where tension is, osteoclasts destroy bone where there is compression

• Teeth: life history

• Permanent molars develop/erupt at ages 6,12,18

• Can see evidence of development and stress on teeth

• …

Social structure

• Can see based on sexual selection

• Male: want to produce as many offspring as possible (more stress for males)

• Female: want to find who would produce strongest offspring

• Monomogus: less sexual dimorphism because no competition, everyone finds someone

• Polygynous: males bigger, show off more to win females over

• Wrangham’s Model: if all descendants share a common social organization, their ancestor probably had the same structure

  • Diet, locomotion, social

Activity Pattern:

• Eyes to skull size

• Diurnal 1:2

• Nocturnal 2:1