NBB 201 Exam 2

What is animal behavior?

how individuals respond to internal and external stimuli - social, structural, physiological

What is ethology?

• study of character

• subfield of biology

What role does Darwin play on behavioral studies?

• foundation of modern study

• said that similar animals exhibit similar ritualized behaviors as well as morphologies, so instincts are also subject to natural selection

• argued evolutionary continuity to emotions

• first to say animals also have emotions

What is evolutionary continuity of emotions? Give an example

• the argument that human emotions are derived from/rooted in animal emotions

• ex) hair raising when scared

• ex) someone baring their teeth when feeling extreme rage

Who are the 3 early ethologists we learned about and what approach did they have?

• Niko Tinbergen

• Karl von Frisch

• Konrad Lorenz

• the watching and wondering approach 

Explain Tinbergen’s studies and what he learned from them

• studies of instinctual behaviors

• learned fixed action patterns, innate releasing mechanisms, sign stimulus, and supernormal stimuli

Explain Tinbergen’s experiment with baby gulls

• the baby gulls peck at a red dot on their parents beak to get food so he presented baby gulls with a normal model head, a model head with no eyes but with a red dot, and a model head with eyes but no red dot, and a red pencil. 

• the baby gulls pecked the most at the red pencil - which was the supernormal stimulus (more intense than normal)

Explain sign stimulus, innate releasing mechanisms, fixed action patterns, and supernormal stimuli? Give example of baby gull

• fixed action pattern = when a trigger sets off a set behavior pattern in an animal that goes through to completion even if the situation changes

  • the baby gulls pecking when they see red

• sign stimulus = what triggers the fixed action pattern

  • the color red for the gulls

• innate releasing mechanisms = the neural network that causes fixed action pattern

• supernormal stimulus = trigger that is more exaggerated than what is normal

  • the red pencil for the gulls 

What are proximate vs ultimate explanations of behavior?

• proximate = in terms of immediate current factors, relevant & measurable at a current time or during development

  • answers what and how

• ultimate = explanation in terms of process and force of evolution

  • answers why

What are Tinbergen’s 4 questions? How are they integrated?

ABCDEF 

Animal Behavior

Proximate:

• Causation = sensory-motor mechanisms

• Development = change over lifetime

Ultimate:

• Evolution 

• Function = survival value

• evolution → development → mechanism → BEHAVIOR → function

What did von Frisch study and what did he learn?

• he studied bees

• found bees have color vision

  • by keeping wells of grey colored nectar with one bright blue one - bees went for blue one showing they see color

• bee waggle dance

  • angle shows hivemates what direction food is

  • duration of dance shows how far it is

What did Kondrad Lorenz study?

• study of imprinting

• baby ducks hatch and whoever they see first they think is there mother who they follower around

What are the 5 factors in which Ethology and Behaviorism differ?

• Ethology

  • European

  • based in biology

  • studied birds, fish, insects, and later primates

  • based on FIELD observations and experiments

  • study instinctive behaviors like parenting or mating

• Behaviorism

  • North American

  • based in psychology

  • studied rats, pigeons, dogs, and primates

  • based on tight LAB control of variables

  • study learned behavior like foraging

What did B.F. Skinner study and claim?

• rats with the lever for food

• claimed behavior is ENTIRELY result of experience

What is behaviorism? What are two laws?

• claims all behaviors are accounted for with a few laws

  • Equipotentiality - claim that any two stimuli can be associated with each other regardless of their nature

  • Pavlov’s Law of Association

    • classical and operant conditioning

    • the dog experiment

  • Little consideration of evolution or of natural behavior

Who is Margaret Altmann?

• one of first women in psychobiology, ethology, and animal husbandry fields

• modern naturalist who studied large animals in natural habitats

• studied endocrine system and sexual cycle in sows and cattle

Who is Charles Henry Turner?

• first person to discover insects can hear and alter behavior based on previous experience

• showed insects were capable of learning

• published paper that honeybees can see color 4 years before Frisch did

What pitfalls should be avoided in understanding behavior?

• should not assume complexity 

  • parsimony is good = assume simplest explanation

• should not ignore umwelt

  • umwelt = perceptual world in which an organism exists and acts as a subject

    • animals have diff sensory systems than us so we should be mindful of how they perceive world when putting them through experiments

    • ex) birds see in UV so they each other has more colorful

    • peacock mantis shrimp have crazy specialized eyes 

    • dogs have insane smelling abilities

  • should not ignore natural proclivities/capabilities

  • should not have stasis - use new methods

Explain behavioral evolution and give examples

• works same way as evolution

  • variation in behavior occurs in a population

  • only individuals with advantageous evolution pass it on to next gen

  • population evolves

• imp to note that virtually every behavior is shaped by genes acting in sequence/coordination to produce that behavior

  • a behavioral trait is controlled for by many genes

    • ex) C. elegans (nematode)

      • only has 302 neurons, but 100 are involved in locomotion and 18 involved in response to touch

  • fox domestication example

Discuss fox domestication in terms of behavioral evolution

• Russian Fox experiment is a proxy for dog domestication processes

• we usually think of evolution as happening over thousands of years only but these foxes changed in less than 50 years

• selection was for tameness but also because many genes control behavior, many other traits also got affected

  • changes in color

  • changes in skull shape/morphology

  • tail wagging

  • reduced fear responses to new objects, people

• correlated traits maintain variation

Discuss behavioral epigenetics, its mechanisms, and give an example

• behavioral epigenetics = interaction of genes and environment in terms of how they affect behavior

  • “how nurture shapes nature”

• epigenetics is a heritable change in gene expression not actual gene sequence

  • change in phenotype not genotype

  • influenced by experience and environment

• mechanisms:

  • DNA methylation - adding methyl groups turns a gene off

  • Histone modification - changes way DNA is packaged which affects gene expression

• ex) anxious rats

  • good mom → pups with low anxiety

  • bad mom → pups with high anxiety

  • but when cross fostered, pups from bad mom had low anxiety when with good mom and pups from good mom still had low anxiety when with bad mom bc some of the genetic factors from good mom were protective

  • licking and grooming by mother resulted in pups with different DNA methylation patterns in stress receptor gene in brain

What is a group? How is that definition different from territory and home range?

• number of animals which remain together in or separate from a larger unit and mostly interact with each other

• different from:

  • territory - where social group lives

    • defended piece of land

  • home range - portion of territory where one spends most of their time

What are the 4 conceptual factors of a social system?

• social organization

• social structure

• mating system

• care system

What are the 5 general types of social groups?

• solitary

• pair-bonded

• 3 group living types:

  • multi-male, one female

  • one male, multi-female

  • multi male, multi female

What are solitary primates? Give an 3 examples

• examples: aye-ayes, tarsiers, orangutans (kind of a rule-breaker)

• significantly correlated with nocturnal activity

• often small body size - not always

• active hours are spent alone - forage alone

  • females usually have kids with them tho

• they gather only for mating or sleeping (provides safety)

• individuals’ homerange overlaps with members of the same and opposite sex 

What are paired primates? Give 3 examples

• ex) owl monkeys, gibbons, and siamangs

• pair-living evolved independently in all major primate radiations

• it is rarest type of social organization

• related to parental care and infanticide avoidance

What are one female multi male primate groups?

• ex) pygmy marmoset

• also very rare

• thought is that these groups start off as a breeding pair and then a second adult male may join and mate with female

• thought to be related to the fact that because pygmy marmosets tend to have twins a lot, extra paternal care is a selective force for them

What are one male multi female primate groups? Give an example

• ex) gorillas

• typically one silverback gorilla (single breeding male) and many females

• both males and females disperse at sexual maturity

• but - about 30% of mountain gorilla groups in Rwanda have multiple silverbacks; even though this is such a classic primate group organization, it seems to be fairly flexible

  • debate why this is case. one thought is that bc of habitat loss, the male gorillas dont have enough area to leave and start their own group that is why they are living like this. even in multi silverback gorillas, only one breeds

What are fission fusion multi-male multi-female primate groups?

• ex) humans, chimps

  • belong to a main group

  • regularly fission into small subgroups or fuse into large subgroups

  • grouping based on a combo of food availability, female estrus status, intergroup interactions, “friendships”

What are multi-level societies in multi-m multi f primate groups? Give 2 examples

• ex) geladas, hamadrya baboons

  • geladas are grass eaters - cow monkeys

    • shuffle eating

    • only found in Ethiopian highlands

• hierarchical groups - many different levels of grouping with final level including hundreds of primates

Define socioecology and give the 2 important questions we ask in it

• deals with social interactions among members of a species and how that interacts with their environment

• Why do animals form groups?

• Why do animals form the groups they do?

What are pressures that organisms want to avoid and what are some they want to find?

• avoid:

  • predators, aggression, disease

• find:

  • food and mates

Explain the relationship between predation pressure and living in groups?

• living in a group reduces predation pressure because it helps with 3 Ds:

  • deter, detect, dilute predators

What are 3 benefits of forming groups?

• reduces predation pressure

  • deter, detect, dilute

• split offspring care - caring for offsprings becomes easy

• group defense - can defend a territory in a group

What are 4 costs of forming groups?

• competition for resources

• social stress

• disease

• infanticide

Why do animals form groups?

• sociality is favored when

  • predation is high 

  • group defense is beneficial

• group size is constrained when 

  • high resource competition

  • disease

What is the socioecological model?

What are limitations of the socioecological model?

• "all models are wrong, some are useful” - G. Box

• breaks/exceptions to model, highlights that resource comp is not what it appears

• models cannot factor in ALL social aspects → social factors, infanticide risk, parental care, disease

• not every habitat represents same adaptive problem

• differences in cognitive ability → alter social relationships and foraging efficiency

• simplifies male and female roles → males also help in resource defense and females are more than just a resource for males bc they also help in resource defense

What is an exception to the socioecological model?

• folivore paradox

  • black and white colobus and mountain gorillas are folivores but still live in pretty small groups even though leaves are a dispersed resource and should inc group size

  • they still have predators so that should also inc group size

  • why do they live in small groups?

    • infanticide risk - larger groups of F may attract outside M

    • best quality leaves may get depleted - low level scramble comp

    • larger group may be impacted by aggressive social dynamics

What is the difference between natural selection and sexual selection?

• natural selection → differential survival

• sexual selection → differential reproduction

What is differential investment for females vs males

• differential investment is also reproductive potential which is basically how much can females vs males contribute to gene pool and how that impacts their sexual selection preferences

• females

  • tend to invest more in offspring

  • reproductive success limited by quality of mate

  • have long gestation periods and lactation periods

    • once pregnant, taken out of the mating pool for a while

• males

  • invest less in offspring

  • reproductive success limited by quantity of mate

What are the major categories of sexual selection?

• intrasexual selection

  • mate competition; between members of one sex competing for mates

  • direct benefits:

    • females, fertilizations

  • indirect benefits:

    • resources, protection/care

• intersexual selection

  • mate choice; typically females choose mates

  • material benefits:

    • parental care, other resoruce

  • indirect benefits:

    • healthy mate, good genes

Explain 2 male reproductive strategies for direct benefits

• 1) compete with other males for mating opportunities (direct benefits)

  • strong selection for traits that help males fights win other males

  • ex) big canines on baboon and gorillas just being big

  • leads to sexual dimorphism

  • but fights are costly - selection should select for way to compete without death or injury → dominance hierarchies

    • dominance hierarchies set up priority of access model

      • males might compete for status by doing big displays of dominance and that gives them power to have priority of access to females

• 2) compete for fertilizations - sperm competition

  • testes vs body weight size

  • monogamous primates had lower testes vs body weight measurement when compared to polygamy and multi-m multi-f group monkeys

Explain 2 male reproductive strategies for indirect benefits

• indirect benefits = not competing directly mating but competing for something else that would attract a female

• 1) compete for territories/resources

• 2) invest in parental care

Explain female pre-copulatory reproductive strategies in material benefits vs indirect benefits

• females look for a good quality mate

• material benefits - who can give her and her kids good material resources

  • look for parental care or other physical resources like land/food

• indirect benefits - who can give her and her kids good genes/health

  • healthy mate - in the current times, make sure he is not sick so she or her kids don’t catch something from him

  • good genes - choose someone with good genes to think ahead for the next generation getting good genes

  • sexy sons - somewhere in evolution of female for that species, a preference for an arbitrary trait arises which has no link to good genes or health. This could be like long tail feathers or something. Females will select mates with that trait so that her sons will have the trait and her daughters will have preference for it

    • AKA runaway selection

How can a female assess genetic quality?

• good genes hypothesis rests on idea that traits are condition dependent

  • so the males have be in good condition and/or have high quality genes to even exhibit these external traits 

  • ex) Mandrill coloration; bright blue color equal more testosterone and dominance rank

Explain why good genes are not universal high quality

• good genes can vary individually based on either compatibility or complementarity 

• ex) rodent females smell to discriminate and choose mates based on MHC (major histocompatibility complex - immune system is strong and varied) that is different from their own to give offspring diverse genes

Explain sexually selected traits in terms of good genes vs sexy sons

• good genes

  • condition dependent → other traits indicate that the individual has good genes

    • ex) Mandrill monkeys with the blue marks indicating they have higher testosterone

• sexy sons - aka runaway selection

  • NOT condition dependent

  • some point in evolution, female preference for trait randomly evolves

  • males with that trait mates more

  • sons have that trait, daughters have the preference

Explain the relationship between natural selection and sexual selection

They balance each other because Darwinian fitness has two components: survival and reproduction.

It is possible that they are sometimes at odds with each other because it is possible that female preference of a trait causes it to eventually become so exaggerated in a species, that it is actually past the optimal intensity of that trait and has started to become disadvantageous for the animal.

• ex) birds and tail length.

• ex) Irish Elk with the huge antlers

What are the female post-copulatory reproductive strategies?

• post-copulatory choice → aka cryptic female choice

  • female’s chemical and physical mechanisms control male’s success of fertilizing an egg

  • choice is not cognitive but evolved

Give 3 examples of evidence of female choosiness

• female chimps going on consortships with middle-low ranking males

• female lemurs show more proceptive behaviors to newly integrated males (who are genetically diff so show they want genetic diversity)

• female choice can also undermine male-male competition

  • females sometimes jump in a fight and support the male they choose

  • significantly influences male reproductive success independent of dominance

Explain infanticide as a male reproductive strategy

When a new male becomes alpha, he kills off all unweaned babies bc when a female is pregnant and lactating she cannot have kids and is therefore out of the mating pool. The new male wants to spread his genes to the next generation so he brings them back into sexual receptivity faster by infanticide.

• ex) Geladas have a 2.5 year interbirth interval and the tenure of an alpha male is about 2-4 years so to make sure he has kids before leaving alpha status, he does infanticide to bring the females back to sexual receptivity

What are the 4 primate mating systems? Give an example for each of them

• promiscuity - many to many

  • bonobos

• polygamy - one to many

  • polygyny - 1 male, many females

    • orangutans

  • polyandry - 1 female, many males

    • marmosets and tamarins

• monogamy - one to one

  • gibbons and siamangs

Give the example of alternative reproductive strategies in orangutans

• 2 distinct male morphs in orangutans - flanged and unflanged

• they each have their distinct mating strategy

• flanged males: call and wait

  • prefer females who have had children before

• unflanged males: sneak and force

  • have offspring with first time mothers

• flanged males may father more offspring but experience higher stress because they have to travel and sometimes have call battles with other orangutans

• it has been seen that unflanged males become flanged and flanged become unflanged

Explain the evolution of same-sex behavior in primates

• it was not studied for the longest time bc researchers considered it an exception but it has since been observed in over 1500 animal species 

• it is the norm not an exception 

• has been seen to increase oxytocin levels in bonobos more than hetero sex

• current working theory is that it can be socially beneficial 

Why do animals exhibit aggression and dominance?

• status

• food

• mates

• territory

• protect kids

• their own life

What are two main ways in which animals fight?

• pure physical aggression → risky and can lead to very dangerous wounds

• displays → costly from an energetic perspective but better way to show they are big and tough compared to getting hurt from pure physical aggression

• stink fights → lemurs use stink fights

Give 4 ways in which animals can gain or exhibit dominance with examples

• size - crayfish

• inheritance - maternal rank inheritance for baboons

• chemical - naked mole rats can suppress reproduction for nearby mole rats through pheromones

• smarts - Mike the tin can pan 

Explain the 2 major types of hierarchies and how they can be applied to individual and group dominance

• Linear

  • very straight and linear line of dominance

  • individual/group A dominates B which dominates C

• Nonlinear

  • One dominant individual/group but the rest are mostly equal

  • or can be circular

    • Individual/group A dominates B which dominates C which can also dominate A

What are the costs and benefits of high rank and of low rank?

• High rank:

  • benefits: access to food and mates

  • costs: maintenance of ranks leads to high cortisol for some species

• Low rank:

  • benefits: group living benefits, wait and see strategy (wait around and see, might get opportunity to achieve a high rank), relatively lower stress levels depending on species

  • costs: lack of access, aggression from other group members, high stress

Why do hierarchies often reduce aggression?

• if hierarchy is stable and certain then everyone knows what their position is and they dont try to resettle it every day

• often if hierarchy is overthrown or unstable, that is when most aggression is seen in primate groups

What is the definition of cooperation?

• helping another individual (increasing their fitness) with no benefit or even at a cost to yourself

Explain cooperation through the theory of kin selection and define inclusive fitness and kin selection

• direct fitness

  • parents help offspring bc their genes are directly getting passed on when their kids have kids

• indirect fitness

  • help non-offspring kin bc they still are related to you and have some of your genes that can get passed on when they have kids

• Inclusive fitness = direct + indirect fitness of an individual

• Kin selection = evolutionary effect of helping relatives

• ex) lionesses will nurse non-offspring kin

Explain Hamilton’s rule

• predicted that altruism should evolve through kin selection if:

  • rB > C

    • r = coefficient of relatedness

    • B = benefits gained by recipients of altruistic act

    • C = costs to altruist in terms of future reproduction

  • basically says that the willingness to help depends on how related you are to the other individual and how much that will cost you

Explain cooperation for non-kin and give example of thought experiment about it

• Hamilton’s rule doesnt apply to non kin but why has that still evolved

• Reciprocal Altruism

  • helping nonkin someone in expectation that favor will be repaid in near future

  • Prisoner’s Dilemma 

Explain the Prisoner’s Dilemma

• in terms of evolution, the best choice would be for you to defect bc if you cooperate you are guaranteed prison time. the only possibility to get off completely scot free is if you deflect.

• For one time interaction: ALWAYS deflect

  • think about the crappy tourist trap souvenirs you buy from vacation that break as soon as you get home → the ppl who sold it to you only see you once so there is no consequence to them that it broke

• For repeated interactions: more cooperative even from non-kin

  • Tit-for-tat

    • if partner cooperates you do too, if partner deflects you do too

    • but if you buy something from your local store and it breaks, youre driving back there and getting a refund or smth so thats why for repeated interactions be more cooperative

What are 3 conditions that must be met for reciprocal altruism to occur?

1. must have repeated interactions with those individuals

2. must have cognitive ability to keep track of altruists and cheaters

3. must have system in which altruists are rewarded and cheaters and punished

Explain what is happening in these graphs

• social exchange has different currencies

• on left, its seen that vervet monkeys jumped into help someone in a fight if they were kin and only jumped in for non-kin if that person had groomed them recently

• on right, its seen that chimps will share meat with someone who groomed them

How to quantify social bonds in primates?

• proximity

• nearest neighbor

• GROOMING 

  • hygiene

  • social bonding

What are 4 types of bonds in social network analysis (SNA)?

• degree = number of connections you have in a social network 

• strength = how tight that bond is

• betweenness = how tightly is an individual connected to someone who isn’t connected to them

  • basically saying you are a connector bw two individuals

• eigenvector centrality = you are only connected to one person but that person is connected to varying levels of connectedness to other ppl

  • “friends of friends”

  • 6 degrees of separation type thing

How important are social bonds? Give 2 examples

• very important for survival 

  • study of white faced capuchins with the amount of grooming relationships actually predicts survival

• also imp for reproduction

  • in chimps, the alpha male had access to females but those subordinate to alpha that were strongly bonded to him had higher reproductive success - short term access

  • AND subordinate males that had strong bonds with each other and not just alpha males had higher reproductive success as well bc it improved their rank - long term access

Explain the Amboseli baboon study and what they learned from it

• often hard to study social bonding in primates bc you have to do super long term studies bc you cant figure out who is related to who w/o it and you cant ask them

• so this is a long term study of Amboseli baboons - 40 yrs of research

• Results

  • They found that there is high infant mortality

  • but baboon babies with highly socially integrated mothers have higher chance of survival

  • and baboon babies with high ranking mothers grow and mature faster

  • and being highly socially integrated is separate from being high ranking

  • also found that social bonds are critical in adulthood as well

    • adult females who were more socially connected lived longer

    • mother’s connectedness in early life linked to daughters’ survival