Primate Behavior Exam 1

Primate Family Lorisidae (consists of?)

These primates are the Lorises (Asia), the Pottos (Africa) and the Galagos (bushbabies). They are Strepsirrhine primates

Asian Loris (range)

South and Southeast Asia - India, Indonesia, Vietnam

Asian Loris (Traits)

Large eyes and reflective tapetum (adapted for nocturnality)
Wet rhinarium
Do not have tails - move quadrupedally through the forests on the branches
Derived feet and hands for searching around the small branch niche for insects and small reptiles - expert insect hunters
They catch their prey by moving very slowing and stealthily through the branches at night, and then quickly grab the prey with two hands

African Pottos (range)

Western and Central Africa

African Pottos (traits)

Large eyes and reflective tapetum (nocturnal)
Wet rhinarium
Vestigial index fingers for moving stealthily through the small branch niche
Have anti-predation adaptations: heavy neck muscles, and toxic tasting saliva (makes the predator spit them out initially so they can escape)

Galagos (range)

Most of continental Africa - from Morocco and Egypt all the way down to the top of South Africa

Galagos (traits)

Fast and agile compared to the Lorises and Pottos
Locomotion: vertical clinging and leaping
Sociality maintained by calls and olfaction "urine washing"

Urine washing

A type of territory marking in which a primate urinates on their hands and feet and marks their territory.

Similarities and differences between Pottos/Lorises and Galagos

Locomotion styles are very different (galagos vertical cling and leap; whereas pottos/lorises are stealthy and slow)
All have nocturnal forward facing eyes with reflective tapetums and a wet rhinarium

Strepsirrhine primates of Madagascar

This is the group of lemurs that have radiated since getting to Madagascar
They evolved in isolation for about 55 million years

Lemurs (general facts)

Evolved on Madagascar for the last 55 million years - adaptive radiation
2000-4000 years ago humans colonized Madagascar - the giant lemurs (like megladapis) have gone extinct in part due to human actions and in part due to climate change
Thought to have gotten to Madagascar by rafting

Differences between lemurs and lorisidae primates

Have a wider range of body sizes
Nocturnal AND diurnal species
Diurnal lemurs have complex social organizations

General Lemur Traits

Little sexual dimorphism in body size
Female dominance in some species
Usually only have one infant at a time

Nocturnal Lemurs: Family Leplimuridae (lepilemur)

Looks similar to a galago - dull coloration to blend in with the environment
Large eyes and ears
Uses vertical clinging and leaping for locomotion
Highly folivorous (primarily feeds on leaves)

Nocturnal Lemurs: Family Cheirogaleidae (pygmy mouse lemur)

Very small body size
Quadrupedal
Also look very similar to the galago
Some hibernate using fat stores in their tails when it gets cold in the parts of Madagascar where they live

Nocturnal Lemurs: Family Daubentoniidae (The Aye-aye)

Extremely primitive primate (but also has a lot of derived characteristics)
One species left
Anti-predation adaptations: camouflage on their face that reflects the moonlight
Highly adapted to a wood-pecker niche - hands are highly derived to take grub out of small holes in trees

Convergent evolution

non-related species that develop similar traits and behaviors in adapting to similar environments

Diurnal Lemurs: Family Lemuridae

Lots of diversity in this family
Comprised of genus lemur, hapelemur, varecia, and eulemur

Adaptive radiation

The formation of a lot of species in a short amount of time because of the availability of new environments

Family: Lemuridae Genus: Hapeleumr

Common name: Bamboo lemur
Found in bamboo forests of Madagascar
Smallest of the diurnal lemurs
Locomotion: vertical clinging and leaping
Highly specialized to bamboo - can eve eat poisonous bamboo

Family: Lemuridae Genus: Varacia

Common name: Ruffed Lemur
Only found in the tops of the trees (despite it's large body size - 9 lbs.)
Quadrupedal locomotion through the trees
Always have either twins (twinning) or triplets
The babies are left in the nests - only lemur to do this
Male care of infants
Main food source is fruit; They use suspensory behavior to get the fruit; and while they feed they pollinate the plants

Family: Lemuridae Genus: Lemur catta

Common name: Ring-tailed lemur
Live in large social groups
Semi-terrestrial locomotion - can walk on the ground
Live in very dry, seasonal habitats
Female dominance - very territorial which results in fights between different groups (the babies hold onto the mothers back when the fight is happening - very dangerous for the babies)

Diurnal Lemurs: Family Indriidae (general traits)

Comprised of propithecus and the indri
They are pretty large in body size (7 lbs.)
Highly specialized for life in the trees (arboreal)
Locomotion: vertical clinging and leaping
Folivorous

Family: Indriidae Genus: Propithecus

Common name: Sifaka
Found in dry forests and rainforests
When they are on the ground they cannot walk - they have to leap because they are so specialized for vertical clinging and leaping in the trees

Family: Indriidae Genus: Indri

Largest of the living lemurs
Found only in rainforest habitat - very derived to arboreality
Has a very short tail - very unusual
Monogamous - uses territorial calls

What makes an animal a mammal?

Mammary glands
Live birth

What makes an animal a primate

Opposable thumbs
Stereoscopic vision
Nails instead of claws

What makes a primate a strepsirrhine?

Wet rhinarium
Grooming claw
Tooth comb
Vestigial index finger - Aye aye derived trait

Why are mainland African and Asian Strepsirrhine primates nocturnal?

Because of the fact that the mainland has many other organisms living on it, so the primates are using the nocturnal niche because they have more competition during the day with the other primates and all the other animals that are diurnal - they have less competition at night and they can use this niche well

Haplorrhine primates (consists of?)

Tarsiiformes, Platyrrhini, and Catarrhini

Haplorrhine primate Family: Tarsiiformes

The tarsiers
Look very primitive
Range: Indonesia and Philippines

Tarsiers (general traits)

Small body size
Locomotion: Vertical clinging and leaping - have extended tarsal bone in the foot that helps them with this movement style
Nocturnal with very large eyes but no reflective tapetum - one of their eyes is bigger than their brain
Faunivorous - only eats animal resources (small reptiles, insects)

Why do the tarsiers have such large eyes and no reflective tapetum?

These primates were once diurnal and then switched to a nocturnal niche to reduce competition - so they adapted huge eyes because they do not have a reflective tapetum

Ecological convergence and Tarsiers

Tree frogs: hind limb anatomy (really large tarsier foot bone)
Owl: "beak-like" incisors that are very sharp (helps them hunt reptiles and insects; flexible neck that can turn almost 360 deg.

Why are Tarsiers not considered Strepsirrhine primates?

Strepsirrhine features: emphasis on olfaction; urine marking; grooming claw
Haplorrhine features: No tapetum, no rhinarium (major difference); no toothcomb

Tarsier life history

Their body mass compares with many strepsirrhine primates, however, their gestation period is around 6 months (closer to haplorrhine primates) - suggests they have a daytime living ancestor and they are more closely related to haplorrhine primates

How have primates entered into the diurnal niche, where most mammals are not active?

Large body size, which allows them to focus on foods not eaten by birds (leaves), and can access and eat larger fruits that birds cannot consume.

Haplorrhine traits compared to strepsirrhine traits

Larger brain
Complete stereoscopic vision
No rhinarium (reduced emphasis on olfaction)
Complete color vision (trichromaticism)
Trends towards larger body sizes

Haplorrhine primates: Platyrrhini

New world monkeys
Central and South America - arrived from Africa about 30 million years ago via rafting
Most are arboreal, forest living species
Larger species have either a prehensile tail or a semi-prehensile tail

Prehensile tail

There is a naked pad on the end of the tail that can support the full weight of the primate

Semi-prehensile tail

A tail that can be wrapped around a branch and can provide some support

Platyrrhini: Family Callitrichidae

Comprised of marmosets and tamarins
Have derived characteristics to feeding on insects and gum - precumbant incisors, claw-like nails
Use scent marking
Twinning (always have twins)
Food sharing and communal care-taking
Live in extended family groups (due to the fact that they do communal care-taking)
Small body size
Male care of infants in many species (very rare)
Social organization: monogamy or polyandry (one female and many males) - both of these are super rare

Marmoset and tamarin phyletic dwarfing

Reduction in body size over evolutionary time - partly due to their life history (long gestation)

General features of a strepsirrhine primate?

Many have a tooth comb
Wet rhinarium
Reflective tapetum
Some have vestigial fingers
Most have grooming claws

General features of a haplorrhine primate?

No wet rhinarium
No reflective tapetum
No tooth comb
No grooming claw
Larger brain to body ratio

General features of tarsiiforme primates?

Derived incisors - "owl like"
No rhinarium
Long gestation
No reflective tapetum
Small body size
Long tarsal bone - "frog like"

General features of a catarrhini primate?

Arboreal and terrestrial
Many have large body size
Some have considerable sexual dimorphism
Some have special adaptations to folivory

General features of a platyrrhini primate?

Primarily arboreal
Many adaptations to a larger body size in arboreal environments: prehensile/semi-prehensile tails
Variety of social systems (some even have communal and male care of infants)

Haplorrhine primate: Family Aotidae

Genus Aotus (night monkey)
Really large eyes - no reflective tapetum
These and the Tarsiers are the only nocturnal haplorrhines - do it to reduce competition with feeding (fruit)
Medium body size
Frugivores and insectivores
Monogamous
Male care of infants
Either have single infant or twins

Why would a haplorrhine primate become nocturnal?

Reduce competition from other primates on the popular foods - fruits especially

Haplorrhine primate: Family: Cebidae

Comprised of genus: Saimiri (squirrel monkey) and genus: Cebus (capuchin monkey)

Family: Cebidae Genus: Saimiri (squirrel monkey)

Small body size
Variable social groups - multi-male/multi-female groups
Large brain weight to body weight
Omnivorous - eat a combination of fruit and insects/small animals (birds)
Unusual habit of smearing food on their tails
Males undergo hormonal based "fattening" prior to mating season

Family: Cebidae Genus: Cebus (Capuchin monkey)

Have true prehensile tails
Largest brain to body weight ratio out of neotropical monkeys
The only neotropical monkeys that know how to use tools - use tools to break open food resources (nuts)
Omnivorous - will eat almost anything (birds, insects, leaves, fruit)
Social organization: multi-male/multi-female groups

Haplorrhine primates: Pithiciidae

Comprised of the Saki and Uakari
Extreme variation in appearance
Dental adaptations allow: extensive seed and nut eating, feeding on unripe fruit

Differences between Saki and Uakari

Fur color is different (S are black with whitish faces; whereas U are red or white with red faces)
U have short, bushy tail; S have long busy tails

Haplorrhine primates: Family: Atelidae

Consists of genus: Alouatta (Howler monkey); genus: Ateles (spider monkey); and genus Brachyteles (wooly spider monkey)
All of these monkeys are highly adapted to life in the trees - they use suspensory locomotion
All have prehensile tails

Family: Atelidae Genus: Alouatta (Howler monkeys)

Folivorous - feed on leaves
Have an enlarged hyoid bone for increased calling (howling)
Sexual dimorphism that includes both body size and fur coloration

Family: Atelidae Genus: Ateles (Spider monkey)

Highly specialized for ripe fruit feeding
Fully prehensile tail
Locomotion: brachiation
Have lost their opposable thumb almost completely - use 4 long digits to swing through the trees
Social organization: multi-male/multi-female groups - based on fission-fusion organization

Brachiation

Arm over arm locomotion through tree environments

Fission-fusion social organization

A type of organization in which groups divide into smaller groups (fission) or come together to make bigger groups (fusion) depending on the availability of food

Family: Atelidae Genus: Brachyteles (Wooly Spider Monkey)

Long arms and short hind limbs
Largest new world monkey
Faculative folivory - can subside on just leaves during lean times, but have adaptations for feeding on fruit during ample times
Locomotion: brachiation
Fluid social organization, including fission-fusion
No sexual dimorphism
Use sperm competition

Sperm competition

Female has sex with multiple males, so instead of the males fighting over the female, their sperm fight to fertilize the egg
Associated with huge testes

Differences between new world monkeys and old world monekys

All species are primarily arboreal
Lots of color schemes in their fur
All diurnal monkeys
Prehensile tails to facilitate large body size
Monogamy and polyandry
Male care and communal care (in Tamarins/Marmosets)
Food sharing (Tamarins/Marmosets)

African/Asian old world monkeys compared to new world monkeys

Most widely distributed non-human primate
Larger body sizes than platyrrhini
Less specialized behavior and locomotion
No prehensile tails
Both arboreal and terrestrial species
No brachiation
Greater hand dexterity

Haplorrhine primates: Family Cercopithicidae

These are catarrhini primates. This family consists of two subfamilies: cercopithecinae and colobinae

Family: Cercopithecidae Subfamily: Cercopithecinae

Consists of both arboreal and terrestrial species
All of these primates have a cheek pouch, a skin layer in which they store high quality food for later

Cercopithecinae: Genus arboreal guenons

Many species are sympatric - live in the same forest
They have differences in color in order to avoid breeding with the wrong species
Social organization: Live in one male/ multi-female groups - some males without groups for bachelor groups of all males
Little sexual dimorphism

Sympatric

Many species in the same genus live in the same forest and share/compete for the same resources

Cercopithecinae: Genus: Macaques

One of the most successful primate groups
Live in many niches - arboreal, terrestrial, and can even live around human made structures (buildings, etc.)

Japanese Macaques

Most northerly primate in the world
Able to survive winter temperatures of 5 deg. F and snow cover up to 1m
They use hot springs to stay warm during the cold days
Eat pine cones and bark in the cold months

"Pre-culture" behavior in macaques

Some macaques have used really interesting behaviors
Imo a Japanese macaque washed the sand off her potatoes in the water before she ate them - this behavior was copied by the younger macaques and then it started to make its way up the hierarchy - however, the alpha males were never observed doing this behavior
Young macaques in the winter have been observed building snowballs for entertainment - this was another behavior that was done by the younger monkeys and then made its way up the hierarchy

Cercopithecinae Genus: Patas monkeys

Range: Along the equator in Africa - in savannah habitats
Fastest primates - can run up to 35 mph
Built like cheetahs - long hind and fore limbs
One male, multi-females groups - most of the time
Highly sexually dimorphic

Cercopithecinae Genus: Drills/Mandrills

Range: Western Africa
Sexually dimorphic in body size and color - male coloration attributed to hormone levels
Sexual swelling
Variable social organization: sometimes all female groups, but sometimes form large hordes of 200 individuals

Sexual swelling

reddening and swelling of skin around the anus and sexual organs, which is tied into the female reproductive cycle

Cercopithecinae Genus: Baboons

Highly adapted to terrestrial environment - foot that is very similar to human foot
Have large canines that they can sharpen on their molars - use the teeth in displays against other males
Live in large multi-male/multi-female groups
Sexual swelling
Omnivorous - eat a variety of plants, as well as animals (insects to baby gazelles)

Cercopithecinae Genus: Galeda Baboons

Live in Ethiopian highlands
Highly sexually dimorphic
Males and females go through puberty to become sexually mature adults
Sexual selection by females - so males have traits that make them stand out (red heart pattern on their fur)
Male on male fighting for females as well - use "lip-flips" and "eyelash" flashes to intimidate other males

Family: Cercopithecidae Subfamily: Colobinae

These are the leaf eating monkeys
Can understand these monkeys in their adaptations to leaf eating
Comprised of B/W colobus monkey, red colobus monkey, and the asian colobine monkey

Advantages and disadvantages of leaf eating

A: super abundant in their environments; easily obtained; plant cell wall is high in fiber and energy
D:Very hard to digest in mammal; need bacteria to assist in digestion

Sacculated stomachs

Stomachs with many chambers that store bacteria to help leaf eating monkeys digest the plant material and nutrients and to reduce toxins in their food

African Colobinae: Black/White colobus monkey

Babies are born a different color - maybe to let the whole group know that they are not a threat since they are a baby monkey
Have reduced thumbs - adapted for arboreality

African Colobinae: Red colobus monkey

They do self-medication - eat charcoal from destructed habitats to facilitate digestion of toxic food sources

Asian Colobinae: Nasalis larvatus (Proboscis monkey)

Easily recognizable with their large nose - females do not have large noses like males (could be sexual selection by females)
Live in mangrove habitats

Asian Colobinae: Rhinopithecus roxellana (Golden-snub nose monkey)

Live in temperate climates
Live in small social groups - one-male/multi-female groups
Significant sexual dimorphism in body size

General features of Cercopithecinae

Cheek pouches (like squirrels); generalized locomotion; dramatic sexual dimorphism; sexual swelling in some genera; large terrestrial forms

General features of Colobinae

Highly specialized to leaf eating - sacculated stomachs; primarily arboreal

Differences between old world monkeys and apes/humans

A/H: anatomy reflects a climbing ancestor (broad chest and pelvic); bigger brains compared to body size; some specialized locomotion styles (knuckle walking/brachiation/bipedalism/quadrumanous); slower gestation and sexual maturity
OWM: Long, flexible spinal column, narrow chest and pelvic

Cercopithecinae overview

Large terrestrial forms
Sexual swelling
Sexual dimorphism between terrestrial forms
Cheek pouches

Colobinae overview

Sacculated stomachs to digest leaves)
Primarily arboreal