ANTH 207

Mating system (or mating unit)

The individuals that mate within a social unit - Describes this subset of social interactions Types: monogamous, polygynangrous, polyandrous, polygynous

lorisiformes --> superfamily --> family

lorisiformes --> lorisoidea --> lorisidae and galagidae

Male-biased dispersal

males leave natal group around age of sexual maturity to find new group. Females are resident in natal group. - Female resident - Matrilocal, form matrilines - Group is female-bonded, tight social bonds. AF-AF relationships predominant - Ex: Cercopithecines (baboons and macaques)

Estrus (Receptive) Females

"Estrus" = the period around ovulation where the female is able to conceive - Females can advertise the timing of their ovulation -- sexual swelling - But some species hav evolved to have concealed or hidden ovulation - May use other cues (e.g. scent, "proceptive" behavior -- females solicit and approach males around time of ovulation)

"Good Genes" Models

"Handicap" models - Propose that ornamentation reduces average male survival, enabling females to assess individual males ability to survive despite his burdensome ornament -- must be of very high quality - Exs: long tail, large horns that aren't functional in combat "Viability Indicator" models - Females assess male characters because they specifically indicate a secondary less apparent trait determining male fitness - That is, male traits can indicate intrinsic features about the male - Examples: testosterone level, parasite load, fighting ability, age, tenure stage

Hominoidea --> Hylobatidae Characteristics

"Lesser Apes" - Two genera: Hylobates (gibbons) and symphalangus (siamangs) - Distribution: SE Asia - Monogamous: live with developing offspring also - Territorial - Duetting: M/F, one sings in sing-songs tone very loudly, and the other responds, pairs that duet more have closer bond. Throat sac helps them produce vocalization. (siamangs) - Suspensory locomotion: brachiation - Anatomical adaptations: long strong arms, elongated hook-like fingers, shortened reduced thumbs, short hind limbs, erect-inflexible spine

Male RS: Sexual Coercion

"Use by a male of force, or threat of force, that functions to increase the chances that a female will mate with him at a time when she is likely to be fertile, and to decrease the chances that she will mate with other males, at some cost to the female."

Multi-level societies

(humans considered to have this) - Vary in complexity - Composed one-male units (OMU) and all-male bands as the most basic level, live in close proximity to other 1 male-multi female units. Not fluid -- always split by OMU - Large groupings at sleep sites common -- groups can get big of units together, broader community in same place, useful as anti-predator behavior Exs: geladas, snub-nosed monkeys

Chemical signals as indicators

- "Stink flirting" in ring tailed lemurs: male olfactory displays to females as honest, costly signals

Male dominance rank acquisition

- A mother's rank may influence her son's rank - In patrilineal species (i.e. male philopatric) - E.g. chimpanzees, bonobos - In matrilocal species where sons of high-ranking females choose to stay -- mother's relationships with higher ranked males in groups pays off for her sons

Copulatory plug:

- A solid plug-like structure that a male ejaculates into the female vaginal canal - Function: to prevent sperm leakage and/or form a barrier that may stop subsequent males from mating - May increase male reproductive success if he mate-guards the females after copulation - Not always effective- subsequent males can remove it when mating, females also remove it - Definitely used by primates

Biological Species Definition/Concept

- Animals that cannot interbreed and produce viable young are considered separate species -- morphology can be deceiving between individuals of the same species looking very different but can and do interbreed, or 2 different species looking very similar but don't recognize each other as viable mates - What if two groups would never be in contact? Never encounter each other because of a mountain range - What if two species can hybridize? They have different behaviors but can interbreed when they overlap in location

Atelidae

- Arboreal - Diurnal - Prehensile tails - polygamous (multi-male/multi-female) - fission-fusion societies

Nature of competition over females determined by

- Asymmetry in male fighting abilities (body size, temperament, testosterone levels) - Effects of male kin (related males around that can help out) - Probability of gaining access to contested female(s) using aggressive versus non-aggressive tactics

Sexually Selected Traits

- Behavioral displays - Acoustic displays - Ornaments - Weapons - Pelage/plumage - Skin colouration - Chemical signals Wasting energy shows possession of energy

Female Rank + Survivorship + Food Shortage

- Benefits of high rank might be the most advantageous when food is scarce - Toque macaques: Rank-related survival during drought - Vervets: high rank females had access to water, low rank females had to leave territory; all mortalities were low rank females

Minerals

- Critical for physiological functions - Examples: calcium, potassium, sodium, zinc, magnesium, etc. - Lack of data on the distribution of minerals across wild primate foods - Fruits are lower in minerals than other food items - Orangutans prefer fruit, but even when there are a lot around, will stop and supplement w eating insects or leaves to get minerals to help digest

Matrilineal hierarchy

- Daughter's inherit mother's rank (like royalty) - Within the matrilineal, they acquire their "intra-familial" rank - Sons do not integrate into the hierarchy (they transfer) -- get preferred treatment when young, don't integrate well into other groups - Stability in rankings over several generations - families remain in their positions

Variation in male relationships

- Determined by the relative strength of competition within and between groups for access to females - Female grouping patterns, reproductive seasonality (food availability), reproductive rates, and mate choices influence the cost and benefits of cooperation and competition among males (high reproductive rates leads to less male competition) -- whether or not worth it for males to cooperate with each othe

Female Callitrichids

- Dominant females use pheromones to suppress the reproductive hormones of other females so that they do not ovulate - Females need helpers because they give birth to twins

Sperm competition

- Even after copulation, there can be post-copulatory competition between males, competition after mating - An alternative to direct aggression between males - Being the sire of the offspring is the reward

Ornaments as indicators (sexual/competitive)

- Ex: blue testes (Cercopithecus aethiops) - Vividness of coloration represents male quality and predicts outcomes of aggressive encounters, higher health status - Ex: throat sac and cheek pads (orangutans) - Function in M-M competition: body size indicator, makes them seem even bigger. Female choice is secondary - Call transmission and reflection: could help in vocal display, longer and choose direction of it

Behavioral displays as indicators (sexual/competitive)

- Ex: stiff leg display, Colobus monkeys - Males vary in their expression of these behaviors (high ranking males display more than low ranking males) - Male displays decreased in vigor over time -- way to show strength, older primates can't do as well - Displays were targeted to other males and groups -- don't mess with him because of it

Male Choice

- Female rank -- some mixed findings across different species about whether they care about female rank in choosing mates - Age -- fairly consistent across primates - Older = higher reproductive value - Primates like older females, the ones with more experience and have reproduced successfully already. Younger females have it difficult to convince males to mate with them, if haven't reproduced - Sexual swellings -- support in Anubis baboons but not in other species -- how red and swollen Males can be choosy too!

Female counterstrategies

- Female resistance - Food transfer -- tolerating female taking food from them - Females test males cooperative tendencies, could be in male's best interest to come off as nonviolent - Adolescent female socio-sexual behavior - work hard to entice males into reproducing with them, usually 20-25 min interaction between flanged males and adolescent females (average typical in orangutans is 7 mins, in chimps 6 secs) -- increases chances for female to seek out male when ready to conceive - Females can avoid flanged males that are aggressive, less choice with unflanged males that aren't as vocal - Promiscuous mating

Extra-group copulations

- Females in pair-bonded, uni- and multi-male groups mate with extra group males = leading to extra group paternities of some offspring - DNA tests revealed these surprising results, occurs more often than expected - Mating unit is not necessarily what is apparent from the social unit - The mating unit does incorporate extra-group copulations

Organization: Fission-Fusion Groups

- Fluid Structure -- groupings change from day to day (foraging groups) - Animals feed/forage in "parties" of differing composition or alone -- size of parties depends on food availability - Group often fuse to sleep - Largest group unit is called a "community" exs: chimps and spider monkeys

Scramble Competition & Female relationships

- Food is low-quality and evenly distributed, thus not monopolizable (leaves or grass) - No overt interactions over food - Nature of relationships: - Females do not form coalitions to defend it (bonds between kin are not as important) - No discernible female dominance hierarchies - Leads to an absence of strong bonds between females

Contest competition

- Food: high-quality, clumped, monopolizable resources - Nature of competition: Direct, aggressive (displacements and aggression over resources) - Affects group members differently ("winners" and "losers" of access) -- some females have much more access to high quality foods as a result

Scramble Competition

- Food: low quality, evenly distributed, not monopolizable resources - Nature of competition: indirect, not aggressive ("first come, first serve" depletion of food sites because other individuals are present) - efficiency in acquiring resources matters - Affects all group members equally

Why are Central and South American monkeys terrestrial, when many monkeys in Asia/Africa are?

- Greater predation pressure for a relatively small-bodied radiation? - snakes/cats, avoid land predators by staying in trees - Availability of productive savannah-type habitats is lower in the neotropics -- more mosaic habitats in Africa, few trees available, food is on the ground as a result need to exploit different resources

Types of sexual coercion seen in orangutans

- Harassment, mate guarding - Forced copulation - infamous for this. Researchers tend to see more forced than cooperative mating events - Infanticide (?)

Primate Feeding Categories

- Herbivores - Carnivores - Omnivores - Flexible feeder - Frugivory: fruit - Gumnivory: sappy, gummy - Insectivory - Folivory: leaves - Gramnivory: grasses and grass seeds (geladas) - Faunivory

Male Callitrichids

- High paternal investment and care - Males in groups are related to offspring and thus, benefit via kin selection -- invest whether or not genetically related - Twins are fraternal and may have different fathers (1/2 siblings born at same time)

Female reproductive strategies differ from male strategies

- Higher parental investment - Less variance in reproductive output - Limited by access to energetic resources - stop cycling when conditions aren't good

Females in provisioned colonies

- Higher reproductive output than non-provisioned, wild groups - Shorter inter-birth intervals - Younger age at first reproduction: maximizes amount of time reproducing, leave more offspring as a result

Lipids

- Highest energy/unit weight - Insects, animal matter, seeds - Not quite as efficient to break down, challenging to come by for primates

Food quality

- How many calories, macronutrients, how easy to digest - Macronutrients - Protein --> amino acids --> stored as glycogen or fat --> oxidized as energy - Fats --> fatty acids --> stored as triglycerides --> fatty acids used to create ketones - Carbohydrates --> glucose --> stored as fat or glycogen --> oxidized as energy All oxidized as energy, broken down into acetyl-coa for atp production - Micronutrients: Vitamins & Minerals

Pelage/Plumage as indicators

- In birds, male plumage brightness and song quality is reduced by chronic parasite infections - With Indian peafowl, long tail requires energy to maintain, and long train is an indicator of good body condition

Contest competition and female relationships

- Individuals cannot always compete because it is dangerous and energetically expensive - food source/resting place/mating opportunity/limiting resource - Establishment of dominance relationships: - Greatly reduces fighting and stress within the group - They "keep the peace" - Strong social bonding for coalitionary partners, form along kin lines

Competition in patrilocal species

- Low risk of take-overs -- no surplus males looking for groups to invade - Need to attract dispersing females: have good territory with lots of resources to maximize their reproductive success -- compete over territory - Patrilocal social groups are rather stable

Friendships in baboons

- Lower-ranking males and females become 'friends - Females prefer mating with the dominant male but form friendships - Preferential grooming - Preferential proximity - Females usually mate with the dominant male but also with her friend (creates paternity confusion) - Male friends protect infants from other males - Friendships end if infant gets killed

Alternative Male Strategies

- Lower-ranking males can form coalitions -- young or reduced fighting capabilities - To try to access females; to either guard the mating pair or keep the high-ranking male occupied or distracted; follow female and mate when dominant male is distracted - Coalitions are also formed when males are in all-male bands -- aids their entry into new groups and helps them over-power resident males - Sneak copulations by extra-group males - "Friendships"

Patrilocal societies and male rank

- Male rank may be influenced by the benefits of remaining with male kin: - Ready coalition partners in between-group competition - Rank based on: extrinsic (e.g., coalitions) and intrinsic (e.g. size) factors - High rank = High Reproductive success - Male hierarchies are not very stable

Callitrichidae

- Marmosets and Tamarins - Reproduce well in captivity - Smallest monkeys - Claws instead of nails (except big toe) - Monogamous and (cooperative) polyandrous groups -- rare, males prefer being loyal to 1 female - have twins -- tend to have them and sometimes triplets, while most primates have 1 baby/birth -- usually energetically expensive, twins don't usually survive in the wild with primates. This is attributed to their small body size - Male care of infants -- obligates males to participate more in child rearing, father carries babies while mom eats, due to expensive energy of multiple births - Little sexual dimorphism - Territorial

Natural selection vs sexual selection

- NS emphasizes survival, SS cuts straight to reproduction - NS emphasizes getting to adulthood, once there SS kicks in - Selective pressure: for NS it is the physical environment and genetics, for SS it is the social environment

Tarsiiformes Characteristics

- Only found in SE Asia - Large eyes and ears (eyeballs bigger than brain size) -- lack tapetum lucidum (eye shine) - Different eye-brain (thalamus) connection than strepsirhines and monkeys -- independent evolutionary lineage - Elongated tarsus bone in foot -- running and jumping, makes them springy but are never really on the ground. Allows them to jump far. - Social system: monogamous (rare in primates) or one-male/multi-female groups

Cryptic female choice

- Phenomenon where the female can manipulate the fertilization and subsequent reproductive events without the male's knowledge -- exerting choice after mating - Important and at play at all levels of reproduction. Steps where females may control which male fertilizes her egg and whether the fetus/infant survives: 1) Discard sperm of current male (for not desirable mate) 2) Re-mate with another male 3) Destroy sperm from mating (e.g. lowering cervical pH) 4) Selectively discard sperm 5) Remove copulatory plug 6) Fail to transport sperm to organs/fertilization sites 7) Bias use of stored sperm 8) Allow or impede induced ovulation (when physical thing induces ovulation, happens in cats with males bite neck to release egg) 9) Fail to prepare uterus for embryo implantation 10) Select for or against sperm during capacitation or hyperactivation 11) Choose among sperm that have reached the egg 12) Abort zygote (The Bruce Effect): after conception has occurred, spontaneously miscarriage. comes from rodents, found in primates (after a change in power, could tell females were pregnant and that were not pregnant before pregnancy became visible, due to stress of the presence of a new male) 13) Allow or impede infanticide 14) Invest less in offspring after birth

Characteristic of Nulliparous Female Sexual Events

- Posture of male - Initiated by female - Long duration - Extensive oro-genital contact - Highly proceptive behavior from female - Great deal of effort for female and restraint for male

Male RS: "Priority of Access" Model

- Prediction: Rank should lead to higher RS - Observation: Male mating success and paternity tend to correlate with rank in primates - Alpha male can probably monopolize estrous females for longer periods of time, which covers her fertile period - most babies in a group sired from alpha male, other males have less but some kids - Competition for rank among males is often equivocal to competition for fertilizations - Explains why males often compete so hard for high dominance rank

female rank and reproductive success

- Priority of Access Model also predicts female RS Yellow baboons: earlier sexual maturity - Higher ranking females reproduce earlier, can leave more offspring than those maturing later - Can ensure access to higher nutrition, allows sexual maturity development earlier Olive baboons: high ranking females have shorter inter birth intervals, higher infant survival, daughters mature faster

Kamikaze Sperm Hypothesis

- Proposes that sperm have different roles (defensive/offensive players) and some act as blockers against other males' sperm while some act as runners going for the ova - Copulatory plug is formed by non-fertilizing sperm, so this may be a possibility in mammals - No evidence in mammals, but seen in invertebrates

Acoustic displays as indicators

- Rate and duration are correlated with a male's competitive ability. High ranking males: - Call more often - Call at faster rates - Call for longer bouts - Give longer 'hoo' syllables - Additionally, call quality decreases with age - The acoustic features of contest wahoos thus potentially allow listeners to assess a male's competitive ability

Skin coloration as indicators

- Red skin in primates often represents testosterone level Chest patch in Geladas - Males with redder chests were higher quality 1) leader males -- the only males with reproductive access to females -- had reddest chests 2) within leader males, males with large units (>6 females) had redder chests than males with small units Skin -- Uakari (the red faced ones) - Lack of pigmentation and intricate capillary system. Indicative of lots of blood flow, high capillary system - Red head of kamari monkeys fade when they are ill -- overall indicator of wellness Skin -- rhesus macaque - Skin becomes bright red during the mating season with fluctuation in hormones - Evidence for female choice of more vivid skin

Evidence for sperm competition in primates

- Relative male testes size to body size - Largest in species where females mate with multiple males - Smallest where females typically mate with only one male -- lots of paternity certainty there - Larger testes produce - Greater quantities of sperm - Greater percentages of motile sperm - Longer sperm (swim faster) - Examples - Muriquis - New world primate, multi-male social group but no observed male-male competition though lots of sperm competition - Lesser galago - larger testes = more mating success

Resident-Nepotistic

- Remaining in your natal group - Using kin as allies in obtaining resources - Inclusive fitness benefits from cooperating w related individuals in the group - HIGH within group contest - LOW between group contest - -small food patches -high contest competition -coalitions among females help them to defend food resources -contests lead to stable dominance hierarchy

High quality foods

- Rich in easily digestible energy and protein; growth diets - Typically colorful, with less hard to digest substances E.g., Fruits, flowers, seeds, young leaves, insects, vertebrates

Taxonomy

- Scientific naming of categories of organisms - Clusters of traits due to common ancestry - Commonly used traits include morphology, genetics, behavior, pelage, vocalizations

Orangutans sexual selection

- Semi-solitary - Flanged males are double the size of adult females - Females hard to come by -- long birthing intervals; have high competition over reproducing females - Profound difference in body size -- heavy selective pressure on males for competing for females to mate with, kill each other in social competition - Large canines - can lead to lethality in competition thru bites - Flanged vs unflanged male morphs

Galagidae (of Lorisiformes) Characteristics

- Sleep inside tree holes during the day - Galagos - Bush babies: comes from vocalization they make, sounds like human baby crying out in the forest - Distribution: Mainland Africa - Arboreal and nocturnal - Vertical clingers and leapers

Lorisidae (of Lorisiformes) Characteristics

- Small, cute, slow moving - Distribution: Central Africa and S/SE Asia - Arboreal and nocturnal - Slow climbers

Social System: Multi-male, multi-female

- Social structure: female-bonded or non-female bonded (neither sex bonded or patrilineal) - Mating system: polygynandrous, both sexes mate with multiple partners - Social organization: variable. Cohesive or fission-fusion, sex ratio of adult males and females varies - Exs: chimps (have fission-fusion societies to form foraging parties, maintain proximity to other parties), baboons (female bonded)

Making plants unattractive

- Some parts of a plant "do not aim" to be eaten (evolutionarily) - Physical deterrents (mechanical challenges) - Physical attributes of the plant that make them unattractive to eat - E.g. protective spines, shells, and husks - Chemical deterrents - Chemical attributes of the plant that make them difficult or dangerous to digest (e.g. tannins (bind to protein, reducing digestibility), alkaloids (bitter tastes))

Making plants attractive

- Some parts of a plant are attractive: - Evolutionarily speaking, the plant "aims" to be eaten - Reproductive parts -- need to survive thru digestive tract - Why? - Primates can be good seed-dispersers thru feces

All-male bands

- Sometimes younger males remain solitary or join an all male band before they enter a group - testing out waters in different communities, to see if have the ability to overthrow a male -- may sneak a mating in - extra-group copulations - No equivalent all-female bands

Sarah Hrdy

- Studied Hanuman langurs - Developed sexual selection hypothesis first, suggested infanticide was connected to energetics - Paternity confusion - Lactational amenorrhea -- not cycling when ovulating so don't release egg. - Noticed that females would mate with homicidal male immediately after they kill the baby, identified it as a male reproductive strategy. - Occurs particularly w nursing babies, attacks stop when they reach a juvenile age

Carbohydrates

- Sugars: monosaccharides, disaccharides, polysaccharides (vary in digestibility) - Readily absorbed by the body and used for energy - Cellulose, hemicellulose -- fermentation (need it to properly break down) - Fruit pulp is a great source of carb-derived energy -- also leaves, bark via fermentation

How do we know features of flanged males are sexually selected?

- These traits are costly, signifying quality and health - Prime and past prime - flanged status is costly. Males tend to die by the time they pass their flanged status. Some males thought to never enter prime stage. - Concentration of mating with flanged males during peri-ovulatory period: evidence that females prefer flanged males as mates. Mate with unflanged males when they are not ovulating

Resident-Nepotistic-Tolerant

- They are also monopolizable and defendable between groups = HIGH between group competition - Females form coalitions to defend food from other groups -- they must cooperate and form strong bonds - Kin are the most reliable allies and aiding them increases your inclusive fitness - Dominant individuals must give something to subordinates in return for joint effort -- FOOD - High (potentially) within-group contest - High between-group contest - Female philopatric - Female ranking = nepotistic but tolerant - Exs: Sulawesi macaques

Within and between-group competition

- Uni-male group (competition against outsider males) vs multi-male group (competition with males w/in group, w incentives to cooperate w same males to protect against outsiders) - Unrelated males do not form coalitions against other groups, while related males do

Masting

- Unpredictable - Irregular - Characterizes Southeast Asian rainforests -- affects different lifestyles of those primates vs primates in other locations - Periods of low fruit and periods of masting (tons of fruit available at one time) - Animals in more predictable seasonal environments have set strategies, the animals in masting environments need to act flexibly

5 Categories of adult male - infant interactions/relationships

- Use and abuse - Tolerance - Occasional affiliation - Affiliation - Intensive caretaking

Vitamins

- Very little is known about nonhuman primate needs and the distribution in wild foods

Types of M-M competition for reproductive opportunities

- Within-group contest competition - Males fighting within the group for high-dominance rank which usually allows them to mate more - Between-group contest competition - Males fight to keep other males out of the group and prevent females from having extra-group copulations - Scramble Competition - Involves no aggression - Sperm competition

Convergent evolution: suspensory locomotion

- ape trait but seen in monkeys in S. America - distantly related species converge on a similar solution to the same ecological pressure

Three key variables affect female feeding behavior

1) Food quality a) Macro/micro nutrients b) Chemical and mechanical challenges 2) Spatial distribution a) Clumped vs widely distributed 3) Temporal availability: when it's available over time a) Seasonality b) Masting

-gamy, -gyny, -andry

-gamy: marriage in anthropology, fertilization in biology -gyny: multiple females (think gynecology, women) -andry: multiple males

Polyandrous

1 female, multiple males More rare

Behaviors that Indicate Strong Relationships between Individuals

1) Affiliation: grooming, huddling, proximity maintenance (preferred social partners spend time close to each other) 2) Agonistic support: coalition forming (to better prevent or perform violence -- shown to have closer social bonds) 3) Minimal aggression: Tolerance of proximity when feeding -- could chase others away from feeding area

How to deal with seasonality

1) Change diet = switch to 'fallback' foods - Black and white colobus rely on mature leaves when other plant parts are not available. Rest more, changes in fertility (fewer conceptions), conserve energy when harder to come by - Fallback foods allow groups to maintain their cohesion in lean times 2) Change ranging/ grouping patterns to maintain high-quality diet

Costs of group living (2)

1) Intra-group competition -- more completion for food because members of the same group are always nearby 2) Increased vulnerability to infectious disease

Why is sexual selection difficult to study in primates?

1) Live a long time and reproduce slowly -- Determining their lifetime reproductive success could take 20 or more years. Hard data to come by, hard to get funding to study 2) Long-term social relationships occur -- hard to determine why a female prefers a male; missed previous relationships forming as an observer, don't know why there are preferences 3) Males often use sexual coercion to mate with females. Males may not be preferred but female mates with him anyway. - Reduces female's capacity to choose who mates with her -- pretty common tactic among male primates

Benefits to group living

1) Resource Defense Hypothesis - Being in a group improves access to resources compared to being alone - Defending food (defend territory big enough for group and protect access for group solely) - Finding food - takes burden off self as individual - Large vs small group advantage As group size went up in capuchins, fights won went up, being a bigger group is advantageous. Doesn't go on forever, will reach a cap where will see an event of fusion where group splits, usually sticking with more closely related individuals 2) Predation Defense hypothesis Being in a group offers better protection from predators: - Collective detection- more eyes and ears to detect predators and alert other group members - Dilution effects- Each individual has less of a chance of being caught, decrease individual chances of being eaten - Deterrence- mobbing can scare off predators. Crowd predator, scaring them, and runs off without eating anybody - During flight- swarming confuses predators. Not good at making multiple decisions during heat of attack Evidence for both of these hypotheses. For resource defense, large groups usually have better access to food patches. For predation defense, terrestrial primates tend to live in larger groups than arboreal ones and some primate species adjust group size to the risk of predation -- the two theories are not mutually exclusive Other benefits once grouped: - Mates readily available and easier to monitor their reproductive state (stage in ovulation) - Increased feeding rates due to decreased individual effort towards vigilance for predators -- don't need to be on high alert yourself for predators while eating - Females and their young may benefit from male protection from conspecifics -- infanticide protection (further stability and protection from intruding male that infants are vulnerable to)

3 difficulties with taxonomic classification

1) There continue to be new primates found; recent orangutan species identified on island of Sumatra 2) Classification problems at the species level - Lumpers vs splitters: tendencies of researchers to either lump individuals into same species or split species at signs of differences in individuals. There are motivations for people to discover new species for resume. 3) Re-classification based on new molecular data - Changing species groupings based on genetic relation

Variability in Maternal Care

1. Age of the mother 2. Parity of the mother (experience) - Nulliparous, primiparous, multiparous 3. Rank of the mother 4. Temperament of the mother 5. Temperament of the infant 6. Species difference 7. Sex of the infant

4 complexes distinct to primates

1. Features of hands and feet - Pentadactyly (other mammals have this though) - Opposable thumb (can take thumb and touch other four fingers) - Grasping hands and feet (human foot is an exception) - Nails (not claws) - Sensitive tactile pads - Power and precision grip (body can support weight well as a result) 2. Visual system aspects - Enhanced vision compared to other mammals - Forward facing eyes -- stereoscopic vision (get accurate depth perception thru overlaps in visual field creating 3D image) -- also found in predatory animals because useful for hunting purposes, jumping from tree to tree and being arboreal, insect hunting - Increased acuity - Trichromatic color vision (due to variation of color in environment, gives ability to distinguish fruits from leaves) - due to enhanced visual system have reduce reliance on olfaction, reduction of the snout, reduction of olfactory brain centers and increase in visual centers, flattened face 3. Large, complex brains - large brains relative to body size compared to other mammals - big neocortex, responsible for cognitive abilities like reasoning and consciousness - link between large brain size, sociality, and learning - in primates, the neocortex makes up 50-80% of brain's total volume - have altricial newborns: single relatively helpless young, have little reliance on instinct so social learning is important, and infants are dependent on mothers for nutrition, social support, and learning - primates vary in their self-sufficiency, overall more helpless young than other animals - expensive tissue hypothesis -- brain tissue is very costly, can't really develop in utero so most happens post birth during development - implications of large brain size: primates have long periods of post natal care, great ability to learn from experience, and great reliance on learning (there is deception in primates which is a high order level of thinking) -- if you are heavily pre-wired at birth you can only behave in a set number of ways, sociality reliance allows for adaptation to very different environments 4. Skeletal and dental features - humans and primates have unspecialized skeletons (particularly in limb structure), allowing for adaptability to diet and demands of their environment - retention of clavicle or collar bone: allows for greater range of motion than specialized quadrupeds - retention of 2 bones in the forearm (radius and ulna) and lower leg (tibia and fibula): accommodates greater flexibility, in horses they are fused to accommodate their type of locomotion - Reduction in number of teeth (compared to other mammals) - Trunkal Uprightness (walk not completely parallel to the ground. Monkeys have a tendency to sit upright). Don't habitually walk upright but have capacity to at some points.

Lorisiformes Characteristics

2 Families: Loris and Galago - Share a common ancestor with lemurs in the Eocene - Nocturnal due to competition on mainland Africa: avoid other primates by being awake in different timeframes - Solitary - Diet: insects and fruit - Lorisidae are found in Asia (lorises) and Africa (loris related species) - Galagidae (galagos) are only found in Africa (bush babies)

Sexual selection

A mechanism proposed by Darwin to explain secondary sexual characteristics. - Darwin realized that some traits possessed by (mostly) males were impossible to explain with natural selection. - Instead of aiding males in survival, these traits seemed detrimental - Not easily explained by natural selection, because not apparently beneficial to survival, sometimes even detrimental to survival - Don't appear until adulthood -- not necessary for survival so don't get until that point

Are primates unique compared to other organisms?

African wild dogs -- highly cooperative in raising pups with males and females feeding them (communal pup raising and feeding), cons: needs to be a limit on the size of the social groups, as tight social bonds are associated with spreading of diseases and decline of wild dog numbers Spotted hyenas: social life more similar to Cercopithecines than other social carnivores, strict hierarchies (definitive alpha and beta with everyone knowing their rankings), coalitions are important, as they work together to fight other groups Lions: females have complex social relationships, no dominance hierarchy (egalitarian), strong between-group competition, cooperative hunting, raising of young and defense against male infanticide (whether or not their kid) African elephants: female philopatric (females stay together for life), complex social structure based on strong matrilineal relationships, old matriarchs (important role socially): hold high ranks, more finely honed social skills, lead group movement, age is directly correlated to group reproductive success - Argued that sociality is not such a key adaptation for other species as it is for primates, not as important - Combination of: 1) Differentiated within-group relationships -- variation and nuance in how close individuals are to each other (ex: hyenas get along with everyone equally w/in social group) 2) Marked social boundaries -- things individuals know to do or not to do 3) Kin-biased social relationships -- matrilines or patrilines 4) Use of allies and coalitions in some species -- differentiated lines within primate groups - these things are more complex in primate social groups, making sociality unique in primates

Intrinsic factors influencing male rank:

Age Size Weight Fighting ability Personality: aggressiveness Baboons and vervets: dominance rank is inversely related to age (varies over lifetime, can change w/in days/weeks)

Intimidation

Aggression to receptive females that may make the female more likely to mate with that male in the future, rather than other males -- been effective

Female-female competition for mates

Among NHP, males are rarely a limiting resource for females. Still occurs when there is variation in male quality (flanged vs unflanged males) But F-F competition for access to males will occur: - In species where males provide a valuable resource or service (give their offspring more access to resources, obligate male care of offspring - want the best caretaker) - More likely in a monogamous unit

Life expectancy

An average computed over all people included those who die shortly after birth, those who die in early adulthood in childbirth or in wars, and those who lived unimpeded until old age

Reproductive Success (RS)

An individual's genetic contribution to future generations - The currency used to measure 'success' in evolutionary terms = the number of offspring an individual produces - females and males have different reproductive "careers" and likewise face different constraints (i.e. limiting resources) on their lifetime reproductive success limiting resource for females = food (conception, gestation, & lactation are energetically expensive) - High access to food ensures their RS more than finding mates limiting resource for males = # of estrus females (to increase reproductive/fertilization attempts) - due to these limiting factors, how primates arrange themselves is influenced - the social organization of primates is representative of females mapping onto the food distribution, and males mapping onto the female distribution.

Hominoidea Characteristics

Apes and humans - No tails - Largest size and weight - Largest brain to body size ratio (brainiest of brainy primates) - More upright posture - Longer gestation and maturation -- pregnant longer relative to lifespan, longer development of children

Mechanisms of sperm competition

Appear to be working in primates: - Volume of sperm and their motility is a factor determining which male's sperm will reach the egg first - Last male precedence: last male to mate with a female is likely going to be the sire of her offspring -- their sperm washes away the other sperm - Timing of ovulation, how many individuals they mate with could lead to this being advantageous - Copulatory plug

Sociobiology

Applying evolutionary principles, specifically natural selection, to behavior (Novel by E.O. Wilson) - Trying to understand how behavior might be naturally selected/adapted/evolved - Asking how behavioral variations give individuals an advantage in survival and reproduction 3 main ideas 1) Kin selection 2) Reciprocal Altruism: traits persisting would make an individual better to reproduce 3) Parental investment Started with the question -- how could altruism evolve?

Protein

Backup form of energy after carbohydrates are ran through - Energy - Growth, tissue replacement - Requirements are highest during growth and reproduction -- elevated in certain times of life -- producing new tissue - Sources: leaves, insects (common source), animal matter

Kin selection

Based on a recognition that: - each individual shares genetic material with their relatives at different levels - Even if you never reproduce, it is possible to have some of your genes represented in the next generation if your relatives are reproductively successful Introduces important new concepts - Natural selection can operate on genes rather than individuals - Inclusive fitness: individual fitness plus the effect upon fitness of relatives

Altruism

Benefits someone else, but comes at a cost to you; helping and selfless behavior - Exs: Predator alarm calls (loud vocalization to let group know of danger - puts self in greater danger thru calling attention), defending group member from a predator (mother helping a baby), helping another individual in a fight (coalition -- why not stay far away and protect one's self), feeding/caring for an infant that is not one's own (babies cost energy, investing energy in them is costly to one's self) - Hard to explain: because we expect behaviors that increase survival and reproductive success to persist, how can it be passed on if it's against natural selection - Originally thought to evolve "for the good of the group," natural selection acting on the group rather than the individual -- for this to work, groups with altruists would have to have higher fitness than those without - But altruists may have decreased reproductive success, while selfish individuals would have better reproductive success. The altruists wouldn't be passing on their genes. - Rejected because natural selection only makes sense if it acts on the individual -- benefitting the group as a whole is unnecessary, should be able to explain it on an individual level, each individual striving to maximize their own reproductive success. Active debate surrounding whether group selection should be reconsidered - Altruism actually ends up evolving by kin selection, not group selection: arise because you are helping someone that is related to you

Genus and species

Both should be written in italics or underlined. First letter of genus is a capital letter

Male Variance in mating success

Can be very high due to - dominance hierarchy - grouping patterns Range: from zero to many offspring From an evolutionary perspective, want to be the male leaving lots of offspring

Catarrhini --> Hominoidea --> Family

Catarrhini --> Hominoidea --> Hylobatidae (lesser apes) and Hominidae (greater apes)

Cercopithecinae vs Colobinae

Cercopithecinae: have more omnivorous diets Colobinae: eat leafs (folivorous) --> have complex stomachs

Catarrhini --> Cercopithecoidea --> family --> subfamily

Cercopithecoidea --> cercopithecidae --> cercopithecinae, colobinae

Langergraber et al 2007

Chimps dispersal pattern: male philopatric (females disperse) Chimps unique cooperation: have high cooperation, share food (meat), cooperatively hunt and kill each other Hypothesis/objective: To what extent is kin selection supported in chimps social groups? methodology improvements: used more genetic data, targeted a lot of loci vs solely maternal/paternal lineage Study significance: cooperative behavior can evolve based off direct and indirect fitness benefits

3 Colobines genera in Africa

Colobus, piliocolobus, procolobus

Harassment

Continually directing sexual solicitations, follows, and perhaps aggression towards females that are reluctant to mate

Mate herding

Controlling female movements, to keep her away from other groups or males.

What does food influence?

Dental morphology (shape of teeth) Skeletal morphology: gut morphology physiology: stress and hunger hormones Social organization/behavior - socioecology

Despotic vs Tolerant

Despotic: clearly established, linear dominance hierarchies. Few reversals (i.e. aggression always directed down the hierarchy) Tolerant: Dominance relationships exist but dominants are tolerant of subordinates and reversals may occur (more fluid bc of social tolerance between females) Presence vs absence of contest competition between groups

Reciprocal altruism

Explains when altruism occurs between non-relatives, as altruism between non-relatives is not explained by kin selection - Helping behavior between non-relatives - Individuals help others so that they will get help in the future when they need it -- grooming or support given to an individual will be reciprocated later -- individuals will cease to help "cheaters" 2 Requirements: 1) sociality: individuals must have the opportunity for repeated interactions, 2) "helping" individuals are of similar abilities (rank, size, etc)

Cercopithecinae Characteristics

Exs: Baboons, Macaques, guenons Old World monkeys - Distribution: Africa and Asia - All diurnal - Many species are large bodied - Diverse diets and a wide range of habitats - Diversity of social organizations many MM/MF within same social group - Some species exhibit extreme sexual dimorphism - More ground dwelling species than any other primate group

Primates family

Family = -IDAE

When females aren't monopolizable

Female grouping patterns are fluid (chimps, spider monkeys) -- sometimes big groups, sometimes small groups - Sperm competition -- less direct forms of competition Reproduction is tightly synchronized (some lemurs, langurs, cercopithecines) - Infanticide: force females back into estrus - Direct hostility limited to brief breeding season: conserve energy most of the time, limit to when females are in ovulation Competition is less direct -- more scramble competition when not monopolizable

Does food influence male sociality?

Food --> females --> frequency of intergroup encounters --> male relationships - Not as directly as female relationships influenced by foood - Low chances of intergroup encounters? - Low need for direct competition within social group, but also no need for cooperation (no driving force to work together to defend a territory)

Forced copulation

Forcing the female to mate when she is unwilling -- behavioral evidence that female does not want to engage

Gorillinae

Gorillas - African great ape - Largest primate: very muscular, heavy animals. Mild-mannered though expected to be ferocious. - Terrestrial: good at tree climbing but spend most time on the ground. Take long naps to digest, spend majority time on ground and make nests at nighttime that are not reused - Highly folivorous -- mostly ear leaves, not known to have eaten meat (never documented) - Dian Fossey -- primary primatologist documenting gorillas - 4 subspecies: Western & Eastern lowland gorillas, and Mountain gorilla (not obvious anatomical differences -- the geographic differences may lead to behavioral differences)

Organization: Cohesive

Group members found relatively near each other most of the time - Animals feed/forage together and see each other most of the time - No change in group membership to sleep or throughout the day - Do not form larger mega-groups or communities

Guenons (Cercopithecus)

Have Diverse Faces (facial markings) that keep guenon monkeys from interbreeding. The facial markings are used to identify mates. They live closely in the same areas but select for mates.

Social organization: neighborhoods

Home ranges overlap, occurrence of sleeping groups and sexual composition is variable ex: orangutans, some nocturnal lemurs and lorises

Hominoidea --> Hominidae --> subfamily --> genus

Hominidae --> Ponginae --> Pongo Hominidae --> Gorillinae --> Gorilla Hominidae --> Homininae --> Pan, Homo

Age-graded societies and male rank

How do they form? - One-male groups become multi-male -- can be patrilineal or both sexes disperse - Fathers allow a son to remain in the natal group or an extra-group male is allowed to join -- father can tolerate son after adulthood, so multi-male group Why do they form? - Offers opportunities to son to reproduce and pass on genetic material - Original male has an ally to repel extra-group males - Easier to protect group w multiple males, than on their own. Sacrifice some reproductive success but not eliminate entirely like if you would lose a fight on your own - Dominant male is usually the only one that mates (in Mt gorillas the second male may sire 15% of offspring)

Size of Food Patch

How many individuals can fit? - Small food patch: cannot support the entire group while feeding = feeding party breaks off, can't have a large social group (ex: chimps) - Large food patch: can support the majority of the group (ex: larger monkeys)

Amenorrhea

If there isn't a lot of energy around to process food, shut reproductive functions down - Females that have a very low percentage of body fat stop cycling - Fat reserves support embryo/fetus during gestation and when the female is nursing later

Paternal Care

Indirect: tolerance, detection, and defense against predators, resource defense for the group Direct: - Direct male care is favored when infants require a high level of investment (e.g. callitrichids) - Male care predicted to be higher when paternity certainty is higher (monogamy)

Parallel dispersal

Individuals emigrating either 1) with other group members or 2) into groups with familiar individuals (knowing someone in new group helps ease transition in for joining). Often members of an age-cohort transfer together Benefits: 1) Having coalition partners may aid their entrance into new groups 2) Individuals can maintain ties with related individuals, even when they change groups 3) Individuals have increased survival because more members during transfer = greater protection from predators. Entering a new group can be dangerous, sometimes have to do trial and error in joining groups

Spatial Distribution of Food Patches

Induce different kinds of competition - protecting certain patches and keeping other individuals out vs not worth it because spread out and accessible - Even: even distribution, low quality foods, not monopolizable (not worth defending), induces scramble competition (not contest: direct competition), e.g. leaves and grass - Clumped: patchy distribution, high quality foods, monopolizable/worth competing over, induces contest competition, e.g. fruit

Infanticide

Infant-killing by males, most extreme form of sexual coercion - Male-male competition may also lead males to kill infants to eliminate another male's offspring and increase their own chances of mating - "Sexual selection hypothesis": only majorly supported hypothesis explaining male infanticide

Female Choice

Inter-sexual selection - Secondary sexual characteristics that give males a reproductive advantage by making them more attractive to females

Male-male competition

Intra-sexual selection - Secondary sexual characteristics that give males a reproductive advantage through competition with other males - Ex: injure other males, could either hurt other male's fitness or hurt their own - Types 1) Contest: physical attacks or threats 2) Scramble: Early search and detection of females that determines the order of contact 3) Endurance rivalry: Time and energy spent seeking, attracting, and defending mates, as well as being reproductively active; living longer than other males lead to more productive opportunities

Asia colobines

Langurs, odd nosed and leaf monkeys

Colobinae Characteristics

Leaf eaters, specialists - Colobus, langurs, leaf and odd nosed monkeys - Distribution: Africa (colobus), & Asia (leaf and odd nosed monkeys - All diurnal - Mostly arboreal (because eat leaves, hard to digest so have complex stomachs to get energy out of cellulose - have to ferment in the stomachs) - Many species are large bodied - Wide range of habitats - Folivorous -- complex stomach, energy minimizers - Diversity of social organizations

Primates Superfamily

Lemuriformes --> Lemuroidea Lorisoformes --> Lorisoidea Tarsiiformes --> Tarsioidea Platyrrhini --> Ceboidea Catarrhini --> Cercopithecoidea and Hominoidea One category splits between Infraorder and Suborder (Catarrhini to Cercopithecoidea and Hominoidea). Can distinguish category by suffix. Superfamily -OIDEA

Linnaean classification system

Life --> Domain --> Kingdom --> Phylum --> Class (mammalia) --> Order (primates) --> Family --> Genus --> Species - Dear King Philip Came Over For Good Soup

Ecology of Male Primate Relationships

Life is easy for males? - Cheap gametes - No gestation - No lactation - Low or no paternal care -- don't need to invest in most species Lower life expectancy for males - Males experience immunosuppressive effects that makes them more vulnerable to disease, dying early - More risk taking behavior thru male-male competition - Life expectancy more similar between males and females in more egalitarian societies Male Reproductive Skew (variation in number of offspring between individuals of the same species): higher when females remain in natal groups, and males compete aggressively for access to females, lower in male philopatric and egalitarian societies

Primate Lifespan

Live longer for their body size, produce fewer babies per year for adult body size

Using and misusing infants

Male baboons carry infants into battle (when fighting, will grab a baby) - Protection hypothesis: maybe his baby, will grab them before things get intense -- to protect offspring? - Agonistic buffering hypothesis: grab infant to protect themself, multiple males mate with a female so paternity confusion, could be the opponent's baby so back down. often not the male grabbing's own baby - Is it effective? -- babies do get injured, females don't give the baby willingly, but it has worked in protecting the male in fights and de-escalating the violence

Sexual coercion

Male reproductive strategy in non-human primates - Naturalistic Fallacy: just because happens in non-human world, does not make it natural for humans to engage in it (common in humans too). Applicable to justifying animal behavior that humans do. Often look to primates for understanding human behavior, but useful to compartmentalize that this is framed around non-humans. - Sexual dimorphism in species makes relationships between the sexes more likely to be characterized by sexual coercion. In species with low dimorphism, don't see it as much (more egalitarian).

Secondary sexual characteristics

Male/female distinctions that appear at puberty - Features of sexual dimorphism (degree varies) - Distinctions between adult males and females that go beyond basic reproductive differences - Examples: Differences in body size, coloration, weaponry, shape, ornamentation - 2 mechanisms leading to their evolution: 1) male-male competition 2) female mate choice - Lines often blurred because the traits that attract the choosing sex cannot always be separated from those that intimidate the competing sex. - Give male a reproductive advantage, while not a survival advantage -- even if males don't live that long, if they don't reproduce well during that brief period when they are in their prime, it doesn't matter - If you have lots of resources, and the predation pressure is low, can evolve non-essential traits

Hamilton's Rule

Mathematical calculation explaining that you are more likely to help individuals related to you. Three variables: 1) cost to actor's individual fitness 2) benefits to the recipient's individual fitness 3) degree of relatedness between the actor and the recipient Individual will be selected to help a relative whenever c < b*r - More likely to help close kin as the costs increase In primates: most altruism in primates does occur between kin -- coalition formation (supporting kin in agonistic encounters), food sharing, social grooming

Catarrhines Characteristics

Monkeys of Africa and Asia, Apes of Africa and Asia, Humans - Nostrils at the bottom of their noses

Platyrrhines Characteristics

Monkeys of C. and S. America - Sideways facing nostrils - All arboreal: bodies specialized for trees because spend vast majority of their time in trees (will come to the ground sometimes though) - Smaller body size than monkeys of Asia and Africa (Catarrhines) - All have tails, S. American monkeys use the tail as an additional limb to grasp stuff - Atelidae have prehensile tails (grasping), andsoem families have partial prehensile tails (not as much dexterity) - Dental formula: 2.1.3.3. - Exs: White-faced capuchin monkeys, callitrichidae

Aotidae

Monotypic: owl monkey - arboreal - only nocturnal monkey, one of two nocturnal haplorrhines (w tarsiers) - monochromatic vision -- advantage in low light conditions - tend to see twins here also - monogamous - paternal care - territorial

Sexual swelling

Most common among cercopithecines (except for a few colobines and chimps) - Visual cue for receptivity/ovulation, for females to advertise they can conceive and induce competition among males. This can increase the quality of the male the female conceives with. - More common in multi-male multi-female mating systems

Odd-nosed monkeys (proboscis)

Nose allows longer male vocalization so it can travel and find females, and keep them within earshot. Females aren't looking at the nose to consider size in mating, but size of the nose makes the male better at vocalization (sexier), and hence more dominant.

Lemuriforme Characteristics

Only in Madagascar, among the world's smallest primates, 5 families - thought to have gotten to Madagascar by "rafting": piece of land broke off and brought some lemur ancestors to Madagascar. Have evidence of lemur ancestors on mainland Africa though they are no longer there - Diversified to fill every niche - Survived on Madagascar but not on the African mainland, likely due to no other primate competition so they thrived - Large lemurs were decimated by human hunting - Diet varies depending on species -- there are generalists and specialists - Some are diurnal but also have nocturnal

Hominoidea --> Hominidae --> Ponginae Characteristics

Orangutans: only Asian Great Ape found in Indonesia (Borneo and Sumatra), fossils found in mainland Asia - Arboreal -- more than other apes, debate on how much time they spend on the ground when not watching (has been caught a lot on hidden cameras) - Semi-solitary -- bizarre for apes, really only found in strepsorhines, no permanent social group, spend time with others for sure though - Frugivorous: preferred diet is fruit. Robust amount of time where no fruit is available to them in SE Asia rain forest. Adaptations are to be frugivorous, though they rely on high density plants a lot - Quadrumanual/Quadrumanous locomotion: in SE Asia, the tree width is skinny (vs like Costa Rica), they use their robust body weight to bend trees, and use all 4 limbs to travel between trees - Flanged vs unflanged males -- some males look a lot like females (unflanged). 2 different male morphs that are fully developed and can reproduce - Orangutan distribution -- species were isolated for a couple million years

Pan genus: bonobos

Pan paniscus - May look the same as a chimp to the untrained eye -- bonobos have a middle part and darker faces though - African apes (bonobos have more limited distribution) - Terrestrial and arboreal - Fission-fusion societies (separate into groups that stay within vocal distance so can communicate) - Frugivorous (supplemented with hunting) - Recent evidence of hunting - Low evidence for tool use outside of captivity -- have capacity to, but haven been posed the need - Male philopatric and female dominant: can displace males easily, males will back off, mothers will fight for sons. As a result less sexual dimorphism. - Low levels of aggression - use knuckle walking and facultative bipedalism (to serve a particular purpose) - have sexual swelling in females, swollen around ovulation, makes males compete and fight to mate. Females tend to select mates and mate w them when most likely to sire offspring. The bigger and pinker, the more the males go crazy. - GG-rubbing: females genital-genital rubbing, do appear to orgasm, females have sex with each other in very high rates, bonobos unusual in how common they do it (multiple times a day) --> good for social behavior (like grooming), done to minimize aggression and conflict - No monogamy - ~2 mya, Congo River changed path, isolating chimps and bonobos, neither species crossed the river so there was species divergence.

Pan genus: Chimpanzees

Pan troglodytes: chimpanzees - closest living relatives, equally close in relation to both chimps and bonobos - African apes - Terrestrial and arboreal - Fission-fusion societies - Omnivorous: tons of fruit, eat meat and hunt other animals, including other primates (can lead them to local extinction) - Hunt (especially red colobus) - Tool use: alter branches and stones to accomplish a task - Male philopatric and male dominant -- female philopatry is more common in apes. Usually see male philopatry and male dominance together, usually bc males are larger than females - High levels of aggression - use knuckle walking and facultative bipedalism (to serve a particular purpose) - have sexual swelling in females, swollen around ovulation, makes males compete and fight to mate. Females tend to select mates and mate w them when most likely to sire offspring. The bigger and pinker, the more the males go crazy. - No monogamy

Bonobos

Patrilineal (male philopatric) - Females are co-dominant with males - Mothers help sons climb the hierarchy, fight on behalf of sons - Benefits of high rank = central location

Male RS: Male monopolization

Potential depends on: 1) number of females in the group 2) the distribution of estrous females: - asynchronous breeding: a single male has a greater chance of monopolizing access to females - ex: hamadryas baboons, white-faced capuchins - synchronous breeding: a single male has less of a chance to monopolize females and prevent other males from having access to the females, lots of females ovulating at the same time - ex: "male influxes" in guenons

Sexually dimorphic traits in primates

Purpose: makes them more competitive against other males or more attractive to females - Really huge canines in male baboons (weapons in intimidating/fighting another male) - Blue scrota == the bluer the scrota, the healthier the male, used in selecting mates. - Red chest patch in male gelada: redder = healthier and higher testosterone - Different anatomy between males and females of same species, certain colorations are connected to social status and testosterone signaling health

Male vs Female Reproductive Investment

Quantity vs quality Males: selection for competition for access to mates; want to find as many opportunities as possible to reproduce. Leave as many deposits as possible, hoping some will seed and end up developing - Have small sperm that are less energetically expensive to produce Females: selection for choosiness about whom she mates with. More invested in quality of male and offspring. Thought to be dependent on her, limited so have to be choosy. - Sex with larger gametes (large eggs) -- inherently limited, require more investment to produce, born with all the eggs they will have. Reproductive mistakes are more costly to females.

Monogamous

Referring to a type of relationship in which one male mates with just one female for at least 1 reproductive event to conceive -- does not mean exclusive entirely More rare - have less sexual selection, low levels of competition

Social System: Uni-male, multi-female

Social structure: neither sex bonded or female-bonded (more common) Mating system: polygynous: males attempt to monopolize access to females and mate with many females, females mate with one male - Intense sexual dimorphism (i.e. body size, canine size)- lots of competition for males to form groups, and keep females from other males, stay w/in eyesight Social organization: cohesive, sometimes multi-level

Social system: uni-female, multi-male

Social structure: neither sex is bonded Mating system: polyandry, only one female in the group OR at least one female in a group but only one is reproductively active (i.e. reproductive suppression of subordinates) - Female that stays in natal group will not cycle -- researchers unsure whether pherehormonal Social organization: cohesive groups (single breeding female, several males with their offspring) Exs: callitrichids (tamarins and marmosets)

Social system: pair-bonded

Social structure: neither sex is bonded (both disperse), 1 M + 1 F live together with kids, leave when reach mature age Mating system: monogamous. Each male invests mainly in one female, presumably the right male makes an important difference in the female's reproductive success (RS) -- but can be polyandrous, matings outside the pair, females can sneak off to other males while partner raises kids from mating Social organization: cohesive, typically stay so can see or hear each other, don't go too far - Exs: gibbons, siamangs, owl monkeys

Cohesive Groups

Stay together all the time Inter-individual distances may vary

Mate guarding

Staying in proximity to the female and aggressively keeping other males away from her (can only be used against less dominant males)

Suborder Strepsirhini - Strepsirhines Characteristics

Strepsirhini --> Lemuriformes and Lorisiformes - "Primitive": retained ancestral traits - Strepsirhines have more shared traits with other mammals, whereas haplorrhines have more derived traits - Distributed in Africa, Asia, and Indonesia - Nocturnal (mostly): have large eyes, eye shine - Wet nose: reliance on scent marking, a higher reliance on smell - Independently mobile ears: can move ears in different directions, mammal trait - Immobile upper lip: fused to their mandible, can't be as expressive w facial communication (inexpressive face) - Dental formula: 2.1.3.3 (more teeth in mouth than other closely related primates to humans). Dental comb (bottom incisors pushed together and forward, to groom themselves). - Grooming claw: single claw on 1 digit, to scratch themselves, pick off bugs and used to clean the anus - Main mode of locomotion: vertical clinging and leaping (unique). Are in upright posture, very springy

Primates Order to Suborder

Strepsirhini and Haplorhini - Strepsirhini (Lemurs, Lorises, Galagos) -- are wet-nosed - Haplorhini (Monkeys, Apes, Humans, Tarsiers) -- are dry-nosed These are new classifications that were shifted due to genetic data

Primates Suborder to Infraorder

Strepsirhini: Lemuriformes, Lorisiformes Haplorhini: Tarsiiformes, Platyrrhini, Catarrhini -Formes and -Rhini

Primates subfamily

Subfamily = -INAE

Haplorhini

Tarsiiformes (difficult tog group historically), Platyrrhini, Catarrhini - All diurnal (except tarsiers and one monkey: owl monkey) - Dry noses: less reliance on olfaction than strepsirhines - Flatter faces as a result (of less olfaction reliance) - Reduced sense of hearing (immobile ears) - Mobile upper lip and highly expressive faces

Weaponry as indicators

Teeth -- mandrills - not an eating adaptation, purpose is weapons, can injury badly and cause infection after, can kill

Social Structure

The pattern of social interactions and resulting relationships within the social unit - Matrilineal (female-bonded), patrilineal (non-female bonded), unrelated (neither sex bonded) - dominance hierarchies

Social System

The set of conspecific (same species) animals that interact regularly and more so with each other than with members of other social units

Social organization

The size, sexual composition, and spatiotemporal cohesion (to what degree do organisms stick together) of a social unit - group size - operational sex ratio: adult male/adult female ratio (tells you how many individuals can mate at a given time, sometimes can even exclude lactating females because they can't reproduce. Also tells you how much male-male competition there is). Types: cohesive, fission-fusion, 'neighborhoods', multi-level societies

Both sexes dispersal

There is some variation where one sex might stay that is supposed to leave. Both sexes can leave the natal group, both sexes can remain resident in natal group. - Neither sex predominantly resident (no one closely related) - Not matrilineal or patrilineal - Neither sex is bonded - Black and gold howlers, gorillas

Ischial Callosities

Thickened skin as a result of repeated contact and friction; used for sitting. Species spend lots of time on the ground, have thick callouses on butt bone to protect exposed skin. Hypothesized function: adaptations that evolved for comfortable and stable sitting on thin branches during feeding in the peripheral branch zone

Pitheciidae

Titi monkeys, sakis, uakaris - Arboreal - Diurnal - Small-medium size - Diverse diets - Diverse social organization: - Titis are monogamous - Others are polygamous (multi-male/multi-female)

Nepotistic (Matrilineal) Hierarchy

WITHIN GROUP contest competition = HIGH - Need to directly compete for food resources within a group - Need allies/strong bonds to access food resources within-group - Kin are the most reliable allies, aiding them increases your inclusive fitness DOMINANCE HIERARCHY BASED ON KINSHIP

Dispersal-egalitarian

WITHIN GROUP contest competition = LOW - Do not need to directly compete for food resources within group - No need for allies to access food resources within-group - Egalitarian relationships = NO DOMINANCE HIERARCHY - Low between-group contest - No female philopatry - Female ranking = egalitarian - E.g. many folivores. Brown lemurs, muriquis

Resident-Egalitarian

WITHIN GROUP contest competition = LOW but BETWEEN GROUP competition = HIGH - the larger area is still worth defending against other groups - No need for allies to access food resources within-group but individuals benefit from staying with kin as residents to cooperate against others - Egalitarian relationships = NO DOMINANCE HIERARCHY - Female philopatric females stay in their natal group, but female hierarchies are weak ex: patas monkeys, mot guenons

Utami et al 2009

What features of orangutans might make them pre-disposed to sexual coercion? - semi-solitary, male bimaturism, extreme sexual dimorphism Do female orangutans display female choice> - Why resist if semi-solitary and not likely to win? Persistently resisting shows the female choice Why be an unflanged male? Why shouldn't all males just flange at puberty? - Flanging is energetically costly, the food is scarce and makes it harder to move -- the flanged males tend to sit, wait, and produce vocalizations and let females come to them. the unflanged males have to move around more to look for reproductive opportunities

Mutualism

When "helping" behavior occurs between non-kin without evidence of reciprocal altruism - Interaction between two organisms where each gains a fitness benefit -- both parties benefit - Interactions can look like a co-operation (i.e. bee pollinating flower, colobus and its gut bacteria -- beneficial to organisms, two males in a coalition -- working together may help both in the long run (e.g. to take over a group), but they will turn on each other as soon as it is not beneficial) - Not altruism because there is no overall cost to the actor in helping

Are male primates choosy?

When it benefits them to be choosy - High variation in female fertility or infant survivorship -- female's ability to conceive/gestate - Synchronized breeding: periods in which females ovulate at the same time -- how to outcompete other males if everyone is conceiving at the same time

Forced Copulations

Which males are responsible? - Used to think just unflanged males, sometimes flanged males too - Usually rare in primates - Porpoises and ducks have forced matings too

Adult Male - Infant Interactions

Why do males interact with infants? - Sexual selection and female choice (males interacting favorably signifies good mate) - Parental investment (more common when paternal certainty elevated, more likely to invest care) - Kin selection - siblings, other maternal kin

Sociogram

a graphic representation of the interaction patterns in a group

Testosterone -- why do females care about male T levels?

a lot of sexual selection tied to this - tied to higher levels of aggression, muscle size, sex drive, competition - defending group from outside competitors -- related to male success in agonistic competition - pass on genes to offspring - suppresses the immune system - if males can maintain ornaments and displays that are mediated by testosterone, without getting sick, they show their superiority - the strength of the males immune function may be heritable, so the females' offspring could benefit -- sexy son hypothesis

Lifespan

an upper bound rather than an average

Fission-fusion societies

break up into foraging for days, come back and break up into little feeding groups - Exs: chimpanzees and atelidae

Ontogeny

development of an organism (usually from fertilization to maturity -- sometimes refers to entire lifespan)

Cheek pouches

ex: in cercopithecinae, particularly bonnet macaque - Used to store food 2 Hypothesized functions (1) cheek pouches reduce vulnerability to predation (2) cheek pouches increase feeding efficiency by reducing competition -- decreases feeding competition within same species because spending time plucking and eating food makes them vulnerable

Life History Theory

explains evolution of life cycle changes through trade offs of growth, maintenance, reproduction - For a period of time, energy is devoted towards growing new tissues and becoming full size - If energy is limited, body may take energy away from growth or reproduction and save towards maintenance. can lead to stunted growth, infertility - When devoting energy to growth, can't be expending energy towards reproduction. Energy tends to switch to reproduction when adult size.

Female-biased dispersal

females leave natal group around age of sexual maturity to find new group. Males are resident in natal group. - Male resident - Patrilocal, form patrilines - Group is non-female-bonded (bc female-bonded is usually the default) -- AM-AM relationships more predominant - Ex: Champs, Red Colobus

Cebidae

include capuchin monkeys and squirrel monkeys

Types of sexual coercion

infanticide harassment intimidation mate guarding mate herding forced copulation

Lemuriformes --> superfamily --> family

lemuriformes --> lemuroidea --> cheirogaleidae, daubentonidae, lemuridae, lepilumeridae, indriidae

Polygynous

one male mates with several females very common

Platyrrhini --> superfamily --> family

platyrrhini --> ceboidea --> cebidae, pitheciidae, callitrichidae, atelidae, aotidae

Low quality foods

poor in energy and protein; subsistence diets E.g. mature leaves, grasses

Socio-ecological theory

predicts that primate social organization responds in predictable ways to food abundance, distribution and quality Food determines the distribution of females and also their within- and between-group relationships

Polygynandrous

primate social system consisting of multiple males and multiple females. Both males and females mating with different partners for reproductive events Very common

Social system: solitary

social structure: neither sex is closely bonded, but related females are often in overlapping ranges -- males typically disperse far away mating system: dispersed polygyny -- males home range overlaps with multiple females home ranges. females affiliate with one another, but no evidence of supported bonds between females (polygynandry in Bornean orangutans)

tarsiiformes --> superfamily --> family

tarsiiformes --> tarsioidea --> tarsiidae