primates Flashcards
(72 cards)
1
Q
homology
A
Close relatives share similar traits due to common ancestry
2
Q
phylogenic contraints
A
Evolutionary history limits the variation observed in current populations/species
3
Q
vestigial traits
A
‘Legacies’ from ancestors that are not functional at present
4
Q
convergence
A
Traits of unrelated or more distantly related groups appear similar due to common selective pressures – rather than common ancestors
5
Q
fossil homindes
A
fossils that no longer are avlive however relate to humans
6
Q
socioecology
A
the relatonship of primate social behaviour and social organisation to the envionment
7
Q
Linnaeus
A
anatomical similarties between monkeys, apes and humans
8
Q
Darwin
A
if man had not been his own classifer he ould never have thought of founding a seperate order for his own reception
9
Q
2 reasons to study primates
A
1- homology: closley related species tend to be similar morphologically becauase they share traits acquired through decent from a common ancestor
2- anaology: natural selection leads to similar organisms in similar environments by assesing the diversity in behaviour and morphology of organisms in relation to their envionment
10
Q
examples of primate evolution
A
1- warfare:
chimps: lethal intergroup aggression
humans: warfare
2- culture and traditions:
humans: chinease eat with chopsticks austrlians use cuttlery
Chip: use stone hammers in africa but not in east africa
3- prosocial behaviour:
humans: act out of self interest but also act on the welfare of others
chimp: spontaneous helping
11
Q
classification
A
hierachy of levels for grouping primates in larger units based on relationship
12
Q
taxonomic groups
A
similar characterstics
13
Q
ancestral traits
A
retained from ancestral groups
14
Q
derived traits
A
newly arising in focal taxon
15
Q
prehensile
A
grasping of hands and feets (opposable big toe)
16
Q
steroscophic vision
A
each eye sends a signal of the visual image to both hemispheres in the brain to create an image with depth
17
Q
binocular vision
A
fields of vision of the 2 eyes overlap so that both eyes perceive the same image
18
Q
colour vision
A
all diurnal primates have it, nocturnal primates don’t
19
Q
Postorbital plate/bar
A
anthropidea: postorbital plate
Prosimii: postorbital bar
20
Q
olfactory apparatus
A
reliance on sense of small
- reduction in sensory areas of brain and in snout
– especially in diurnal primate
21
Q
unspecialised teeth
A
Utility – processing food – weapons in conflicts • Primates have generalized dentition • Teeth tell us something about – dietary preferences – age of individuals and developmental patterns – phylogenetic relationships – social structure
22
Q
dental formulas
A
top jaw/lower jaw
2123
2123
23
Q
primate evloution: large brain
A
Primates generally evolved larger body size • Brain increases with increase in body size • Primate brains increased in size more rapidly than body size
24
Q
themes of evolutionary diversification within order
A
- mode of locomotion
- dentiton and diet
- sociality
- brain development
25
prosimians
```
- Prosimii (‘before monkeys’)
• Earliest primate group 55+ MYA
• More reliance on olfaction
– long snout
– moist, fleshy pad (rhinarium) at
end of nose
– use scent marking
– “split” upper lip
– Dental comb
– Unfused mandible (lower jaw bones)
– Post orbital bar, not plate
– Many nocturnal
• Tapetum lucidum
• reflective layer in eye that
maximizes use of light
• Quadrupedal & mostly arboreal
```
26
prosimii lorisoidea
```
• 2 families
– Lorises (Lorisisdae)
– Galagos (Galagidae)
• Africa and SE Asia
• 2133/2133
• Quadrupedal climbers
• Nocturnal, arboreal,
solitary
• Leave their dependent
offspring in nests
```
27
family lorisidae
```
Nycticebus coucang
(Slow loris):
SE Asia
• 400 grams
• Nocturnal
• Diet: tree gum
Loris tardigradus
(Slender loris):
S India
• 200 grams
• “Banana on stilts”
• Slow and cryptic
• Powerful grasp
• Nocturnal
• Diet: fruit and
insects
```
28
family Galagidae
```
Continental Africa
• Long bushy tails
• Large ear pinna
• Nocturnal
• Leapers
• Diet: fruit, gum, animal
```
29
Prosimii: lemuroidea
```
Madagascar
• Diverse taxon
• Most nocturnal
• Most arboreal
• Some torpor
– state of decreased
physiological activity
• Females dominant
```
30
lemuridae:
```
Madagascar
• 3 kg
• Monomorphic
– males & females alike
• Diurnal, partly terrestrial
• Diet: fruit, leaves
• Social
• Females dominant
• Scent mark vegetation
• Males display waving
‘scented’ tails (‘stink fight’)
```
31
Lemuroidea: Indridae
```
Madagascar
• Diurnal, arboreal
• Ca 7 kg
• Vertical clinging &
leaping
• Diet: leaves, fruit
• Monogamous
```
32
Tarsioidea
```
• East Asia
• Nocturnal and arboreal
• 110 grams
• Dental formula 2133/1133
• Diet: 100% animal prey
• Incomplete post orbital plate
• Grooming claws (2)
• Eye larger than brain
• Rotate head almost 180
degrees
• Clinging and leaping
• Solitary (except females +
young)
```
33
anthropoidea
```
• Single clade (all from one
ancestor)
• No grooming claw (all
nails)
• No tapetum lucidum
(only 1 nocturnal genus)
• Largely diurnal
• Fused lower jaw
• Short snout / reduced
olfactory reliance
• Continuous hairy dry upper
lip
• Postorbital plate
• Larger relative brain size
than prosimians
```
34
Platyrrhini (‘flat noses’):
Ceboidea (New World
Monkeys)
```
• Only Ceboidea (but not all) have
prehensile (grasping) tails
• Dental usually 2133/2133
• Sideways-facing nares (nostrils)
• Completely arboreal
• Diurnal (except 1 genus)
• Two large families
– Cebidae
– Callitrichidae
```
35
Cebidae
```
Diverse family
• 5 subfamilies
• Dental 2133/2133
• >3-8 kg
• All nails
• Many with
prehensile tail
• Diurnal
• Leaves, fruit,
animal matter
```
36
Callitrichidae
```
All < 1 kg
• Dental = 2132/2132
(molar reduction!)
• Claw-like nails
(reversal) except 1
st
toe
• Quadrupedal
• Diurnal
• Diet: fruit, gum,
animal
• Family groups of 5-
10
• Most twin
```
37
Catarrhini (‘narrow noses’):
| Cercopithecoidea
```
• 1 family (Cercopithecidae) = Old
World monkeys
• Dental: 2123/2123
• Bilophodont molars
• Ischial callosities near tail
• Some with sexual swellings
• Tail never prehensile
• Wide variety of habitats
• 2 subfamilies
• Cercopithicinae
– largely fruit eating
• Colobinae
– largely leaf eating
```
38
Colobinae
```
Africa, Asia
• Arboreal (most)
• Leaf and seed eaters,
lichen (some)
• Have complex stomachs
• Often found in ‘harems’
```
39
Cercopithecinae
```
Africa & Asia
• Variable in size
• Typically live in medium or
large bisexual groups
(multimale-multifemale)
```
40
Examples of Cercopithecinae
- Patas (Erythrocebus)
- Mandrill (Mandrillus)
- Japanese macaque
41
Catarrhini: Hominoidea (apes and humans)
```
Larger body (usually)
• No tails
• Limb arrangement reflecting
brachiation
– rotation of shoulder & scapula
– ventral-dorsal flattening of trunk
(shallow chest)
– wrist joint flexibility
• Longer forelimb than hindlimb
– human reversal
• Y-5 molars on mandible
• Relatively even larger brains
• Prolonged dependency of young
```
42
Hominoidea: Hylobatidae
```
SE Asia
• Diurnal, arboreal
• 6-8 kg
• Brachiators
• Ischial callosities
• Monomorphic body size
(but some dichromatism)
• Mostly fruit
• Monogamous
• Territorial
• Vocal duets
```
43
Hominoidea: Pongidae
```
Orangutan (Pongo)
– 2 species
• Borneo & Sumatra
• Ca 37-77 kg
• Males 2x female body weight
• No ischial callosities
• Quadrumanous
• Cheek flanges in dominant males
• Diurnal, arboreal
• Fruit, leaves, animal
• Most solitary
• Slowest life history of all primates
– age at first reproduction: 15 yrs
– inter-birth interval: 9 yrs
```
44
Hominoidea: Hominidae
```
Gorilla (Gorilla)
• 70-170 kg; males = 2x
females
• No ischial callosities
• Knuckle walk
• More terrestrial
• Mainly folivorous
• Typically in one-male
groups
```
45
Hominoidea: Hominidae
```
2 species
– chimpanzee
– bonobo
• 31-60 kg; sex
dimorph varies
• Knuckle walk
• Quadruped;
climbing
• Fruit, leaves,
animals
```
46
Behavioural peculiarities of chimps and bonobos
- large mixed sec communities
- chimps modify natural objects for use as tool in the wild
- chimps co-operativley hunt other primates
- bonobos: 'make love not war' ape
47
evolution of primate traits
• Natural selection → increased efficiency of behaviours in particular environments
- Some individuals better able to produce more offspring →left
more copies of their genes
48
behavioural ecology
- the study of behaviour from an evolutionary and ecological perspective
- Behaviour is a product of
natural selection on ancestral populations resulting in increased adaptation to particular habitat
• Anatomical traits and
behaviour linked
49
socioecology
```
• Social system evolves in
response to ecological
conditions
• Availability and distribution of resources →
– competition
– grouping
– social behaviour
– mating patterns
• Social behaviour is a suite
of adaptations to the
ecological and social
environment
```
50
social organization
group compositon and spatiotemproal cohesion
51
social structure
social interactions and relationships
52
mating system
whos mates with whom and what are the genetic consequences
53
what is needed to survive
```
Find food
– Find and co-ordinate with mate
– Have offspring & rear offspring
– Avoid parasites
– Avoid predators
```
54
pros of living in a group
defense of territory/food
resources & mates from
competitors
– lower risk of predation
55
cons of living in a group
```
Costs
– increased competition for
resources (food, mates)
– increased likelihood of
disease and parasite
transmission
– increased consp
```
56
benefits of sociality
```
lower risk of predation
Detection
• more eyes to detect predators
Deterrence
• more individuals to mob or chase
predators away
Dilution
• smaller chance that any one individual
is the prey of the day when group is
larger-
```
57
what is the optimal group size
```
The size and
composition of groups
reflects a compromise
between the costs and
benefits of sociality
for individuals
```
58
what is reproductive success limited by?
females: access to resources
males: access to females
ecological pressures: influnce the distrabution of females, and males distribute themselves to maximize their access to females
59
explain/define the food that is needed
```
• Supplies energy
requirements for survival,
growth & reproduction
• Dietary specializations
drive numerous
specializations
– body size
– teeth form and number
– gut length
– hand (shape, function)
– locomotor and suspensory
systems
– brain size
• Different kinds of foods in
different kinds of habitats
are distributed differently
in space and time
```
60
what are the major adaptations to the digestive tract in primates and colobines
Primates unable to digest cellulose → microorganism for cellulose digestion
Colobines: complex multi-chambered stomach with cellulose-digesting bacteria
61
effect of resource distrabution
High-quality food such as fruits have patchier distributions than low quality foods such as leaves
62
what are the types of competition and how does this affect resources
- scramble: “first come first serve”
- Food is evenly distributed
- Amount of food available per individual decreases with increasing group size
- contest: Food is found in defensible clumps
– Individuals compete
aggressively over access to
resources
63
why do animals disperse
```
Avoid inbreeding
– reason in many cases for
natal dispersal but does not
explain secondary dispersal
• Seeking better resources
– plays important role
secondary dispersal
• Result of intrasexual
competition-
– but does not explain
species where individuals
leave voluntarily
```
64
solitary
males defend home ranges tha encompass home ranges of several females
65
monogamous pairs
when females are dispersed males may associate permanently with one of them
66
polyandry
several males associate with one repoductive female
67
polygyny
if females are clumped in groups one male may be able to monopolize access to a group
68
male infanticide
Infanticide by males is major source of infant mortality in primates
– especially in single-male groups
• Most cases of infanticide follow changes in male residence (eg. takeovers) or dominance rank
69
human mating system and the types of mating that i allowed
• Majority of human societies allow polygyny
• but its frequency depends on subsistence
style:
– monogamy predominates in forager societies
– pastoralists and agriculturalists show significant
polygyny
70
sexual dimorphism
Correlation between sexual size dimorphism and polygyny in many mammalian groups
• Pronounced body size dimorphism is suggestive of
high levels of male–male competition
71
how does testis size affect the mating system
Primate species in promiscuous mating systems have much larger testes relative to body size than primates in single-male groups
• Humans: mild level of promiscuity
72
sprem competition in humans
* Male ejaculate volume reflects risk of extra-pair copulation (EPC)
* Ejaculate volume from copulations correlated with length of time for which couple were apart – effect independent of time since last copulation
* → Functions to maximise probability of conception by swamping any rival sperm
