our primate relatives Flashcards
why are primates studied
because it helps us learn about humans as models for anatomy, behavior, and shared adaptations
what are the four main categories of derived traits for PRIMATES
- post cranium
- cranium
- life history
- ecology & habitat
what does postcranium mean
anything that is not the head
list some post cranium adaptations of primates
-pentadactyly
-prehensile hands
-hallax
-nails
-finger/toe pads
-finger prints
-hind-limb dominated locomotion
-tendency toward vertical postures
-clavicle gives more shoulder motion
what is pentadactyly
having 5 fingers or 5 toes on each hand/foot
what is prehensile hands
adapted for grasping
what is the hallax and why do humans not have it
hallax is the opposable big toe
humans dont have and we have the derived trait of inline big toes
what are some cranium adaptations of primates
-decreased olfaction
-emphasized vision
-post orbital bar
-forward facing eyes
-stereoscopic vision
-increased visual processing
-less prognathic
-encephalization quotient
-function based dentition
what is decreased olfaction
less reliance on scent
what is the post orbital bar
the eye has a bone going around it that is completely closed if there is a post orbital bar, but if not there would be a hole or it wouldnt be present at all
what is stereoscopic vision
depth perception
what is less prognathic mean
less of a snout
what is the encephalization quotient
EQ is the brain:body size ratio
humans have large brain for a smaller body
what are the four types of teeth
what is human dentition formula
incisors, canine, premolars and molars
2 1 2 3
what does life history mean as an adaptation of primates
how the animal spreads growth & reproduction out over its lifetime
what is unique about primates life history vs other animals
primates LIVE SLOW LIVE LONG while most animals LIVE FAST DIE YOUNG
what are some characteristics of the adapted life history of primates
-long lives
-later reproduction
-single offspring at a time
-long interbirth intervals
-long gestation
-lots of investment of offspring
-long infant dependency
what are the ecological adaptations of primates
-tropical distribution
-relatively omnivorous
-diurnal
-social living
-behavior learning & flexibility
what are the names of the two theories for why primates have derived these traits from the last common ancestor
arboreal hypothesis
visual predation hypothesis
what is the arboreal hypothesis
primates have these derived traits because they adapted to living in a 3D arboreal environment (xyz axis)
what is the visual predation hypothesis
primates have the derived traits because it makes them more competitive as predators
convergence of traits with predators who rely on vision and grabbing to catch prey.
what are primates most closest relatives
bats, tree shrews, colugos
what is the typical environment that primates live in
tropical areas or forest bc arboreal
where are fossils of primates found vs where are they living today (exclude humans obv)
found in north america and europe, living in the americas, africa and asia
about how many primate species are there in the world
300
T/F all primate species are equally related to one another
FALSE
taxonomy order go
domain
kingdom
phylum
class
order
family
genus
species
dom the
king
purchased
cats
on
friday
+ genus + species
what are the two major suborders of primates
Strepsirrhine and Haplorrhine
what primate species are strepsirrhines
lemurs and lorises
what primate species are haplorrhines
tarsiers
NW monkeys
OW monkeys
apes
what species are platyrrhines
NW monkeys
what species are catarrhines
OW monkeys & apes
where are strepsirrhines found
africa asia and madagascar
what are some tarsier traits
-huge eyes
-tiny body & small brain
-cling & leap locomotion
-insectivores
where are platyrrhines found
tropical forests of central and south america
what are some common NW monkey species
squirrel monkey, spider monkey, capuchin monkey
what are some NW monkey traits
-arboreal quadrupeds
-smaller than catarrhines
what is the common name of the family cercopithecoidea
OW monkeys
where are OW monkeys found
africa and asia
what are some examples of OW monkey species
colobus monkey, baboons, macaques
what are the names of the two groups within the family apes
lesser apes and greater apes
what are the species within the category lesser apes
gibbons & siamangs
what are the species within the category greater apes
orangutans, gorillas, chimpanzees, bonobos, humans
what is the orangutan genus
pongo
what is the gorilla genus
gorilla
what is the chimpanzee & bonobo genus
pan
what is the human genus
homo
draw the flow chart cladogram of all apes
siamangs & gibbons
orangutans
gorillas
humans
chimps & bonobos
T/F apes have large brains
TRUE relative to their body size & in general
T/F some apes have tails
FALSE apes are tailless
what are some traits of the lesser apes
-arboreal
-very long arms
-brachiators (swing from branches)
-pair bonding
-territorial duets
what primate is only found in borneo & sumatra
orangutans
what is the largest arboreal animal
orangutans
what are orangutans eating habits, social habits, and mating habits
-fruit leaves & bark
-solitary
-male to male competition for mates
T/F there is a northern and southern gorilla
FALSE it is western and eastern gorilla
where are gorillas mostly found
central africa
what is the largest ape
gorilla
what are gorillas eating, and social habits
-mixed vegetation & fruit
-one male + multi female
where are bonobos found
congo
T/F bonobos have strong female bonding
TRUE
what are bonobos eating, social and mating/dispersal habits
-fruit, vegetation & some meat
-multi male + multi female
-female dispersal when reproductive age hits
where are chimpanzees found
equatorial africa
T/F chimpanzees have strong female bonding
FALSE they have strong male bonding
what are chimpanzees eating, social, and mating/dispersal habits
-fruit, vegetation & meat
-multi male + multi female
-female dispersal
what percent of the day to primates typically spend eating
80%
what are the four factors that determine how much food a primate needs
- basal metabolic rate
- active metabolism
- growth rate
- reproductive effort
what are traits of insectivores
-eat insects
-small body size
-sharp high crests on molars
-simple digestive system
what are traits of folivores
-eat leaves
-large body size
-sharp shearing crests on molars
-enlarged and developed digestive system
what are traits of frugivores
-eat fruits
-medium body size
-low cusp flat molars
-large but unspecialized digestive system
what are traits of gumnivores
-eat gum/sap
-small body size
-long robust incisors
-claws sometimes
what primates will sometimes eat other monkeys
chimpanzees
what are tubers
roots (potatoes carrots) and some primates eat tubers too
rank the diet types from smallest body size to largest body size
- gumnivore
- insectivore
- frugivore
- folivore
T/F primates eat primarily plant products
TRUE
T/F primates want to gain the most carbs possible
FALSE they will focus on eating one food high in carbs and another food high in protein to stay balanced
T/F diet can affect home ranges
TRUE the accessibility of food can change where the species chooses to live, and some seasons will have more present food than others
T/F primates are nomadic
FALSE they are not wanderers and will typically have a home range
what is a home range vs a territory
home range is the area of land covered by the normal movements and activities of the species
territory is when a home range is being defended
what are some common predators of primates
-snakes
-crocodiles
-raptors
-carnivores
-other primates
-humans
T/F terrestrial primates are most susceptible to predation
TRUE
what traits have terrestrial primates evolved that reduce predation
larger body sizes and bigger group living and vocalizing alarm calls
what are the benefits to a bigger group size
-detection: more individuals to see predator
-deterrence: mob of animals is harder to attack than a lone one
-dilution: less individual chance of getting eaten when more individuals to take from
T/F vervet monkeys have specialized alarm calls for different predators
TRUE
which haplorrhines are NOT social
tarsiers and orangutans are not social
since haplorrhines are social, what kind of trait is solidarity for orangutans
a derived trait
what are benefits of group living
-avoidance of predators (ddd & chance of being eaten)
-inter-group feeding competition (group members will defend feeding sites from other groups)
-more access to mates
-can displace other groups
what are costs of group living
-intra-group feeding competition (other members get there first)
-mating competition
-interbreeding more likely
-disease spreading
what are the names of the 5 types of social living groups
-solitary
-pair bonded
-polyandry
-polygyny one male
-polygyny multi male
what is the solitary social group and what species do it
just mom and kids until they grow up and leave
orangutans
what is the pair bonded social group and what species do it
one male and one female
gibbons & siamangs
what is the polyandrous social group and what species do it
one female with multiple males
NW monkeys
what is the polygynous one male social group and what species do it
one male and multiple females
gorillas
what is the polygynous multi male social group and what species do it
multiple males and multiple females
chimpanzees and bonobos
what does it mean to be philopatric
when the primates disperse and immigrate to new communities
what is female philopatry and what species is it found in
when the MALES disperse to other groups and the female remains in the same place
-gorillas, baboons and monkeys
what is male philopatry and what species is it found in
when the FEMALES disperse to other groups and the male remains in the same place
-chimpanzees and bonobos
what is a mating system
the way that a species finds mates and cares for offspring
what is mammalian asymmetry and give some examples
mammal traits that constrain evolution
(mammals will all inevitably have these things, so evolution must work around them and cannot change them)
-sexual reproduction
-female gestation
-female lactation
-variation in reproductive success (# offspring)
what is optimization
maximizing benefits and minimizing costs
T/F reproductive effort is referring to the mating effort of the individuals
FALSE it refers to the mating effort and the parenting effort of the individuals
what is the general reproductive effort for a male-female relationship and what is it called
males invest more in mating, females invest more in parenting
called reproductive asymmetry: different investment strategies based on sex
what are male reproductive strategies
- focus on finding new mates
- focus on helping offspring survive
since chimps are a solitary species, what changes about their reproductive strategies
there is not paternal care, so the father might not even recognize their own offspring, only the mother touches the baby for the first few months
what are the ways that females are biologically required to invest in their offspring
growing the baby during gestation is energetically demanding and there are long lactation periods that require energy
T/F limited resources equates to a higher age of maturation and a longer interbirth period
TRUE because they are unable to have the resources to sustain their gestation periods or raise the offspring without starving
T/F humans are weird bc they live a long time after they last give birth
TRUE most other primates give birth until they die
what is lactational amenorrhea
this is the thing that determines the interbirth period
this means that the breastfeeding is temporarily preventing pregnancy because they will be infertile and without a period by changing the hormones when the baby is sucking the nipple
-helps with not over making babies for the mother to have to take care of
-quantity vs quality
what is weaning
when the infant becomes more independent and breastfeeding is stopped so the mother has enough energy to conceive again
how does rank increase reproductive success
because it makes resources more available bc they can take from lower ranked individuals
what is the monogamy mating system
mating system that mates with only one other individual during a specific mating period
DOES NOT NECESSARILY MEAN PAIR BONDED
what is serial monogamy
where they switch partners every mating season
lifelong monogamy is not common but serial monogamy is
what is extra pair copulations and why might it happen
copulation outside of the partnership for this mating period
-females want this to happen to ensure they get pregnant and may have multiple males providing for her and offspring
-males want this to have as many offspring as possible because they can and why not
what are the two types of polygamy mating systems and what does polygamy mean
polyandry and polygyny
-means mating with more than one individual during a specific mating season
what is the polyandry mating system
one female mating with multiple males
what is the polygyny mating system
one male mating with multiple females
why would females like polygamy
because they would have multiple males who have a chance of the offspring being theres, so they can bring more resources to her
what is mate guarding and what mating system is it common in
common in polygyny mating system where the males will physically prevent the female from mating with other males
what is the polygyny threshold model
predicts that females will choose to have a polygynous mate when it is most beneficial to their offspring instead of some other choice
-if monogamy and polygyny would both produce reproductive success, then the female would rather choose monogamy
what is the biggest limiting factor for female reproductive success
resources
what is the biggest limiting factor for male reproductive success
access to females
what is sexual dimorphism
male and female have different traits/sizes
T/F increased male aggression shows decreased sexual dimorphism
FALSE they would both be increased
what is sexual selection
a form of natural selection that comes from one sex preferentially picking their mates based on their features
what is intrasexual selection
males compete against each other to get a female
what is intersexual selection
females choose the most attractive traits for her mate
T/F increased male to male competition will increase sexual dimorphism
TRUE pair bonds have low dimorphism
one male multi female has super high
multi male multi female has middle
what is estrus
the portion of the female reproductive cycle when fertilization of the egg is possible
how is teste size affected by competition
more competition between the males means that the testes are smaller because once they win the competition, their sperm dont necessarily need to perform better bc the female is solely theirs (gorillas)
less competition means that the sperm needs to be more and work better so the testes would be bigger to try to win against the other sperm in reaching the egg (chimpanzees)
humans have some competition but are mostly just based on other traits, so they have relatively middle body:teste ratio
what is a copulatory plug (sperm plug)
something that is ejaculated into the female that clogs the pathway so that other males sperm cannot reach the egg and their sperm can have a better chance of staying in to reach the egg (found in chimps)
what is infanticide
a male reproductive tactic where they kill the infants so the female can reproduce faster by ending lactational amenorrhea
what are female counterstrategies to infanticide
-extend their swelling periods so they can copulate with more males, so that they all could think that the infant is theirs and so will be less likely to kill it (paternity confusion)
-they can cause an abortion to happen by stress to avoid all together
why should they not be called monkey bars
because the apes are the ones that would actual swing like this, the monkeys probably wouldve just crawled on top not swung
what is the thought of how chimps and bonobos separated into different species
allopatric speciation from the congo river couldve put some chimps in the other size and they evolved into bonobos
what is fission-fusion dynamics in the chimps & bonobo populations
where they sleep all together at night, but then during the day they will separate into smaller groups but then come back together at night again
T/F chimps & bonobos have sexual swelling
TRUE
T/F chimps are thought to be “peaceful” and bonobos are thought to be “aggressive”
FALSE chimps = aggressive
bonobos = peaceful
although we see this might not actually be the case
T/F bonobos have longer sexual swelling periods that chimps
TRUE
T/F chimpanzees have more female to male aggression
FALSE bonobos have more (think about pulling branch video with the females attacking males because they were dragging it)
T/F in chimps and bonobos, more aggressive males = more copulations with females
TRUE
are chimps or bonobos better to study for humans
both have similarities and differences, so a mix of both is probably best
(used to only study chimps but that isnt beneficial bc both have similarities and differences that could help)
what is the chimpanzees coalition strategy
working together to fight against other chimps
what is the bonobo individualistic strategy
working alone to fight other bonobos
T/F studies show that bonobos are more aggressive than their “peaceful” description previously thought
TRUE
what kind of teeth do primates have
heterodont teeth
what is the pattern in ape teeth and the name
Y pattern into 5 sections
BUNODONT
what is the pattern in OW monkey teeth and the name
t pattern into 4 sections
BILOPHODONT
what are some examples of cooperative living
grooming, alarm calls, alliances, and predator defense
why would cooperative living be beneficial
-if the food is hard to find but would feed a lot of individuals once found
-predator awareness and deterrance
what is the prisoners dilemma and how does it relate to cooperative living
where depending on who confesses the amount of time spent in jail would change
-relates because they have to weigh the potential benefits and costs that would could from doing a specific action or not
what is altruism and what is it in terms of evolution
taking a cost to benefit another individual (aka cooperation)
-in terms of evolution, it is doing something that would be beneficial for your genes to survive in the long run
what is the kin selection and inclusive fitness theories of altruism
and what is direct vs indirect reproduction
kin selection: there’s more altruism when the individuals are related
inclusive fitness theory: the combined fitness will benefit from direct and indirect reproduction
-direct means that you are benefitting your (or your family’s) direct gene reproduction
-indirect means that you are benefitting individuals with a portion of your genes (other more distant relatives like a niece/cousin)
what is hamiltons rule
rb > c for the action to be beneficial
rb < c for the action to not be beneficial
r = coefficient of relatedness
b = benefits in fitness units
c = costs in fitness units
what are the coefficients of relatedness for siblings/ parents
and for half siblings/ grandparents/ aunts/ uncles
and for cousins/ half aunt/ half uncle
and for identical twins
0.5
0.25
0.125
1.0
what is reciprocal altruism
you will do something for someone now, with the intention that they will do something for you in the future
like an IOU of benefits/costs
-creates a net benefit from the interaction usually
what are some things that are needed to have reciprocal altruism present
-recognition of individual identities
-memories of past actions
-cannot be solitary primates bc prob wont see again (needs regular interaction btwn individuals)
