Lectures pre M1 Flashcards

Question

Placebo effect - acupuncture

Answer 1

The expectation and anticipation of clinical improvement Indicated by: large difference between sham treatment (placebo) and no treatment (same treatment) acupuncture and sham (placebo) treatment both had the same score

Answer 2

- Spontaneous improvement - Statistical regression to the mean = a statistical phenomenon that can make natural variation in repeated data look like real change - Placebo effect (psychological factors) - Biases (e.g. patient being polite) - Co-interventions (e.g. pain killers)

Answer 3

Ultimate = Why? - function - adaptive significance EVOLUTIONARY FORCES Proximate = How? - mechanism - machinery (genetics, physiology, neurobiology) - operate within the lifetime of an organism NATURAL SELECTION

Answer 4

Glucocorticoid hormones such as corticosterone have been linked to stress responses, so birds on the edge of the expansion (furthest from Mombasa), and hence in the most novel environments, would show the strongest surge in corticosterone when exposed to a stressor (especially during breeding season)

Answer 5

Proximate perspective (how): increased corticosterone leads to better memory of stressors Ultimate perspective (why): the payoffs for better memory in environments with novel and unpredictable stressors should be greatest in leading edge populations during invasions

Answer 6

Ultimate - Why do males, but not females, actively search for carotenoid-based foods ~helps males obtain mates - Why do females prefer males with bright plumage ~disease resistance, feed offspring more, better foragers

Answer 7

Proximate - What causes between-population differences in female coloration ~availability of carotenoid foods - What causes males and females to differ in plumage colouration ~different foraging strategies

Answer 8

a proximate cause

Answer 9

a communication network that influences many aspects of animal behaviour (hormones released by either ductless glands or neurons) - Primarily composed of a group of ductless glands that secrete hormones directly into blood

Answer 10

- adrenal gland - pituitary gland - thyroid gland - pancreas - gonads - hypothalamus hyposecretion or hypersecretion affects functions like growth, metabolism, reactions to stress, aggression, and reproduction

Answer 11

Cells within endocrine glands that synthesize and then secrete hormones

Answer 12

Hormones that can be released directly into the blood by neurons (typically in the brain)

Answer 13

act as chemical messengers, affecting target cells that reside some distance from the gland-secreting hormone - same hormone can have different effects on different target cells - almost always transported through the bloodstream and all cells (except one) in the body have a direct blood supply

Answer 14

cells with the receptor site for a particular hormone - hormone has no effect on a cell unless the cell has the correct receptor 1. hormone reaches the cell and binds to the receptor site 2. a series of interactions occurs that affects gene expression and protein synthesis 3. these changes and directly or indirectly affect an animal’s behaviour

Answer 15

the receptor site (lock) on the surface of the cell is not activated until the correct hormone (key) reaches it

Answer 16

- Breeding season = spring/summer = cued by changes in day length Day lengths increase → increase in levels of gonadotropin (sperm production) and testosterone (makes males more aggressive towards one another to get females, guard mates, build nests, and defend their brood)

Answer 17

hormones made up of strings of amino acid - can be stored in endocrine cells for delayed release - hydrophilic (aq soluble) so they don't need a carrier chemical - larger = greater half-life - most common hormone in vertebrates If small: peptide hormones (ex. prolactin)

Answer 18

ex. testosterone - can't be stored = immediate release - hydrophobic so they need a chemical chaperone to move them through the bloodstream - bigger lag time between stimulus and production (compared to protein)

Answer 19

is designed to draw tourists to beautiful ecologically endangered areas of the world, using the funds generated from this tourism to protect the wildlife in these areas, and to promote the local, often indigenous, human culture that lives around the ecotourism site

Answer 20

- Adults exposed to tourists have habituated to their presence and show reduced defensive responses (and corticosterone) in the presence of humans vs with those not exposed - Very young penguins exposed to tourists showed much higher levels of stress hormones (plasma corticosterone) than those from control groups Why? - in ecotourism areas habituated adults leave nest and spend less time brooding as they walk near humans - causes stress + temperature change stress for chicks

Answer 21

1. Input system: made up of all the sensory systems (smell, sight, etc) 2. A central processor: made up of integrators that process and integrate the sensory info received 3. Output system: effectors such as muscles that move when stimulated

Answer 22

prime animals so that they are more or less likely to behave in a specific way in a specific environment ex. testosterone and winning a fight feedback loop when baseline levels of testosterone are high, males are primed for aggressive behaviour when encountering another male (if they win a fight due to high baseline testosterone, this increases testosterone more)

Answer 23

if a developing male mouse fetus is surrounded by females, it’s exposed to lower levels of circulating testosterone, so it will be less aggressive and less sexually active than males that were surrounded by male fetuses

Answer 24

1. Stressor (ex. predator) 2. hypothalamus responds along two pathways a. first pathway - burst in epinephrine (adrenaline) and norepinephrine leads to an increase in blood sugar and oxygen delivered to vital organs - nonessential systems (digestive, reproductive) are shut down b. second pathway The following hormones are released by the hypothalamus to increase sugars: - corticotropin-releasing hormone (CRH): leads to ↑ cortisol - growth hormone-releasing hormone (GHRH) - thyrotropin-releasing hormone (TRH) - Aldosterone production to increase water retention and reduce bleeding if the stressor causes injury

Answer 25

- testosterone levels in 2M males were significantly higher than in 2F males Caused them to -mount females faster and ejaculate sooner - have more offspring - spent less time with offspring after birth (less parental care)

Answer 26

Preoptic area of the hypothalamus (gerbils): controls copulatory behavior + is sexually dimorphic, meaning that males and females show different activity patterns in the preoptic area - 2M females have preoptic metabolic activity that resembles that of males more than that of 2F females - 2M females have 20 percent greater metabolic activity in the preoptic area of the hypothalamus than do 2F females

Answer 27

important roles in social behaviours like reproduction + parental care in mammals

Answer 28

Prairie voles are monogamous: - both males/females have a single mate each breeding season - males display parental care and guard their mates Reason: more vasopressin receptors in the ventral pallidum area Meadow voles are polygynous: - males mate with multiple females during a breeding season - males do not display much/any parental care or prosocial behaviour towards mates Reason: fewer vasopressin receptors in the ventral pallidum area Experimental administration of vasopressin to male prairie voles increases monogamous behaviours, while administration to meadow voles does not b/c meadow voles lack the receptors to bind the extra vasopressin NEED RECEPTORS TO GET MORE VASOPRESSIN

Answer 29

when bees usually go from housekeeping to foraging for food outside of the nest, it is associated with an increase in juvenile hormone III (JH III) - increase in JH III is correlated with the shift to the forager stage - bees that had been allatectomized (and thus had no JH III) began foraging significantly later than bees in control groups, poor navigators, no other major behavioural changes

Answer 30

- Modulates learning + memory in honeybees - Forager bees have higher concentrations of octopamine in their brains - Octopamine reaches its highest concentration when a bee switches from nest bound activities to foraging activities (including foraging-related flight behaviour)

Answer 31

2 types Type I - males build nests - 4x larger - higher gonad-to-body size ratio - produce sounds in many behavioural contexts: grunts when in aggressive contexts with other males, hums when courting females - if selected as a mate, remains on the nest after a female lays her eggs there Type II - “sneakers”: they don’t build nests, but stay around the nests of type I males, then dart in and shed sperm in an attempt to fertilise the nesting female - small - lower gonad-to-body size ratio - do not hum to attract females, rarely grunt type I males: higher Kt (testosterone androgen) - associated with sound production - and lower cortisol type II males: higher cortisol (glucocorticoids)

Answer 32

Midshipman’s vocal organ is a set of paired sonic muscles. - innervated by "pacemaker" neurons Type I males: - larger sonic muscles w/ more muscle fibres - pacemaker neurons fire at a rate of 15-20% higher than type II - Arginine vasotocin (AVT) inhibits activity in the neurobiological circuitry associated with sound production - Isotocin (IT) has no effect on sound production Type II males: - smaller sonic muscles - pacemaker neurons fire at a lower rate - AVT does not affect vocal motor activity and sound production - IT inhibits activity in the neurobiological circuitry associated with sound production

Answer 33

neurological underpinnings of behaviour (nervous system and behaviour)

Answer 34

specialized nerve cells that have an axon and fire action potentials - over evolution, neurons that served specific functions became clustered

Answer 35

nerve fibres that transmit electrical information from one cell to another - morphological variation = speed of nervous impulse affects the speed at which animals respond behaviorally. thicker diameter = faster impulse - each neuron has a single axon

Answer 36

- fibres on the neuron that receive impulses from other cells

Answer 37

- stimulus - reach threshold and fire an action potential - at the end of an axon impulse jumps against the synaptic gap or releases neurotransmitters - ends when terminal neurons stimulate the effector (ex. a muscle) or with the secretion of a chemical that causes an endocrine gland to secrete a hormone

Answer 38

In invertebrates, spatial navigation is associated with this cluster of neurons at the front of the brain - lets foragers have spatial navigation through visual or olfactory cues - mushroom bodies of foragers were larger than of younger nurses

Answer 39

- formed a colony composed only of one-day-old bees to induce early foraging behaviour - bees in the experimental treatment began foraging at around four to seven days of age - the configuration of the mushroom bodies in these advanced foragers resembled that of normal-aged foragers = NEURAL PLASTICITY

Answer 40

- puzzle box to get to food inside - mammalian carnivores with brain sizes that are relatively large for their body mass are better at solving foraging-related problems

Answer 41

Unihemispheric sleep - Mallards can sleep with one eye open and one hemisphere of the brain awake, a behavior that allows them to stay alert to predators while resting Position matters - Mallards on the edge of a group rely more on unihemispheric sleep compared to those in the center, showing that birds adjust their sleep behavior based on predation risk. Birds on the edges sleep with the open eye facing away from the group, toward potential predators. Slow-wave sleep - EEG recordings show that the sleeping hemisphere enters a state called slow-wave sleep, which allows for quick responses to danger while not fully waking the bird. This signature sleep pattern ensures that the bird remains partially alert even during rest. - Unihemispheric sleep is also observed in aquatic mammals like dolphins, whales, and seals. It helps them perform critical tasks, such as swimming to the surface to breathe while sleeping.

Answer 42

self generated movement of either a body part or the whole body in animals

Answer 43

Major components of behaviour that most species have: 1. Feeding 2. Fleeing 3. Fornicating / reproducing - Producing offspring for females, successfully reproducing for males 4. Fighting/aggression - Not necessary but common - Most commonly for access to (good quality/safe) food or females

Answer 44

1. Survival 2. Growth 3. Reproduction 4. Ageing

Answer 45

Fitness = survival + reproduction A young animal must avoid being someone's food and feed to grow and avoid starvation

Answer 46

1. Evolution: change over generations in the proportions of individual organisms differing genetically in one or more traits 2. Learning

Answer 47

1. Evolution: change over generations in the proportions of individual organisms differing genetically in one or more traits 2. Experience-based adaptation: changes resulting from exercise, pupil adaptation to light, acclimation to temp, altitude, etc. 3. Age-related changes: growth, ageing, etc.

Answer 48

A change over generations in the proportions of individual organisms differing genetically in one or more trait

Answer 49

- Attract and court females - Other communication (threat, ownership, asking for food) - In many species only males sing

Answer 50

Male cricket must sing to attract and mate with females, but singing may attract Ormia flies which kill the male Female ormia parasites lay eggs on the crickets and larvae consume them Evolved flat wings that vibrate but cause no sound Wings more similar to those of females Rapid, independent evolution (separate islands) of flat wings within 12-20 gens CONVERGENT EVOLUTION

Answer 51

- Females have become less selective - Silent males approach calling males and attempt to intercept approaching females

Answer 52

the ability to acquire an internal representation of new information → An individual may use that information to determine subsequent behaviour

Answer 53

- balanced diet vs deficient diet - citral or coumarin odours - brown or green card - learning treatment group or random treatment group - learn through colour, taste, location - allowed to learn ‘naturally’ to prefer balanced over deficient diet - learning resulted in 20% higher growth rate usually = reproductive success

Answer 54

Individual learning - Info lost when the individual dies Social learning - Learning from other individuals - Info continues on for generations - Faster spread of learned behaviour

Answer 55

the study of animal behaviour

Answer 56

Mechanism: What stimuli elicit behaviour? What sort of neurobiological and hormonal changes occur in response to, or in anticipation of, such stimuli? Development: How does behaviour change with the ontogeny, or development, of an organism? How does developmental variation affect behaviour later in life? Survival value: How does behaviour affect survival and reproduction? Evolutionary history: How does behaviour vary as a result of evolutionary history, or phylogeny? When did a behaviour first appear in the evolutionary history of the species under study? M/D proximate S/E ultimate

Answer 57

Scientific observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.

Answer 58

Cocoa vs. cinnamon food Should I eat new food? Unfamiliar food may be highly nutritious, but it could be spoiled or poisonous Learning through eating the food is risky Learning from others is safe Observers that interacted with demonstrators who ate cocoa preferred cocoa Vice versa for cinnamon Can be passed along through generations (ex. From observers to their children) Cultural transmission via social learning

Answer 59

1. natural selection ex. silent crickets and mole rat xenophobia 2. individual learning ex. grasshopper balanced diets, female bird mate choice 3. cultural transmission ex. cocoa rats

Answer 60

Behaviour is the coordinated responses of whole living organisms to internal and/or external stimuli

Answer 61

- Tightly knit groups as only one breeding pair so they’re all genetic relatives - Those in moist mesic environments have less resource scarcity than those in arid environments - More aggression towards strangers in arid populations with resource scarcity - Less aggression when male-female interactions than same-sex bc they still need a few new members to come breed

Answer 62

- Female bird mates with multiple males in her life and prefers the ones whose offspring were successful or who make good mates

Answer 63

1. Conceptual - integrating formerly unconnected ideas - ex. kin selection and indirect vs direct fitness = inclusive fitness 2. Theoretical - Entails the generation of some sort of mathematical model of the world Ex. models to maximise energy when choosing prey or foraging - Not trying to mimic the natural world, more so trying to make predictions that may or may not match real behaviour 3. Empirical - Observational or experimental studies - Correlation ≠ causation - Experimental better for understanding correlation than observational

Answer 64

a transmission system in which animals learn through various forms of social learning

Answer 65

Microbial evolution and growth arena plate (MEGA) 120 x 60cm Visual observation of bacterial evolution on a large antibiotic landscape Duration 2 weeks X-axis = antibiotic concentration

Answer 66

the identification by humans of desirable traits in plants and animals, and the steps taken to enhance and perpetuate those traits in future generations

Answer 67

- reinforce behaviours like general activity, obedience training, concentration, affection demand, aggression toward dogs, anxiety, and interest in targets

Answer 68

- To study the evolutionary biology and mechanisms of aggression (ex. In anderson lab) - Have 20 000 genes, many similar to humans - Used to learn about cancer, parkinsons - Aggression used to learn about depression, etc. - Shine light that activates neurons and makes them fight or flirt, same neurons! Emotional arousal

Answer 69

- both must have heritable variation A.S.: the variation in reproductive success (fitness) of individuals is determined by humans who decide which individuals reproduce N.S.: the variation in reproductive success (fitness) of individuals is determined naturally

Answer 70

Uninheritable - Language - Cultural customs, religion, dressing style, traditions - Skills - Hair style and skin tan Inheritable - basically everything else

Answer 71

Lifetime reproductive success - product of reproductive rate and length of reproductive lifespan

Answer 72

Females rarely survive till 3 years to even start reproducing (see graph) Average 6-7 babies/lifetime Males also rarely make it to reproductive maturity Many males still don’t have babies even if they make it to reproductive age Most females DO have babies if they make it to reproductive age

Answer 73

- Take lab born fish, one group from population evolved in high predation pool and other from low predation pools - Use 2nd generation lab-raised individuals to ensure real predation experience doesn’t affect their behaviour (To eliminate parental effects) - Measured average distance between 4 individuals in the presence and absence of predator-induced alarm pheromones - Fish at high predation pools have evolved tendencies to form larger groups - Fish at high predation pools also have evolved more effective predator inspection (more frequent and from farther distance) Result: matched the behaviour of their ancestors (-ish)

Answer 74

Chromosome: long strand of DNA consisting of different genes Gene: the functional unit of heredity Locus: a site on the chromosome occupied by a certain gene Allele: one of several forms of the same gene Mutation: alteration of a DNA sequence

Answer 75

- many genes involved in a trait's expression - QTLs (quantitative trait loci) are genes that control polygenic traits - if the inheritance of a genetic marker is associated with the inheritance of a particular trait, the marker must be linked to the trait

Answer 76

Determined by only one gene - H is close to C marker

Answer 77

- Preparation for bad situations - Many emotion levels are adaptive - Being more anxious means you take less risks = you live longer

Answer 78

Variance (σ2), standard deviation (σ, or SD) and standard error (s or SE)

Answer 79

Genetic variance = average amount of variance among genotypes Environmental variance = average amount of variance among individuals within the same genotype

Answer 80

- Young bees start as cleaners, then feed larvae, then feed nestmates, then pack pollen, then forage - Respond to the demand over their life ie. young can be foragers or old can become nurses - Analysis of ~5500 genes (out of ~14,000) ~2000 genes showed different levels of expression in nurses & foragers - Can modify genes if demand for a specific role is needed “for” gene is seen more in foragers - Identified by Marla Sokolowsky - ForS are sitters and move less, forR are rovers and move further

Answer 81

Genetic variance + environmental variance Vp = Vg + Ve

Answer 82

h^2 = (Vg) / (Vg + Ve) Vg = Genetic variance Ve = Environmental variance

Answer 83

h^2 = (Va) / (Vp) proportion of phenotypic variance caused by additive genetic variance Va = additive genetic variance unlike Vg which consists of additive and non-additive Narrow-sense heritability = slope of the regression

Answer 84

the deviation from the mean phenotype due to inheritance of a particular allele and this allele's relative (to the mean phenotype of the population) effect on phenotype

Answer 85

Heritability

Answer 86

- Great hovering ability while stationary - Then go dive for fish - Bring the fish to the ladies

Answer 87

Many small islands are used as “natural labs” for experiments, observation, manipulation, replication in natural populations

Answer 88

- Introduced curly to island with only anoles (control), number of anoles decreased and more likely to become extinct - Began to move to higher thinner branches to avoid predation shortly after import of predators (within a year) - Natural selection acting on morphology - Males with longer limbs to run faster and escape from predators - Females who were larger and faster to escape and harder to eat once caught

Answer 89

- What animals do and why they do it (ultimate question) - How evolutionary processes shape traits

Answer 90

- Since late 1950s - Dmitri Belyaev and Lyudmila Trut selecting tamest and most docile foxes in Siberia - Only allow tamest - calmest and prosocial towards humans - to breed and parent the next generation - Has produced tame foxes that can be held and pet by humans, and who seek human contact

Answer 91

Common suite of traits including… - Floppy ears - Mottled colouration - Curly tails - Juvenile characteristics

Answer 92

- Belyaev thought trait byproduct of selection for tame behaviour and humans have always just selected for tameness and all other traits are just genetically linked to changes in tameness - Wrangham says neural crest cells explain how tameness is linked to domestication syndrome; during embryonic development these cells move along the neural crest then migrate to other areas, selection for tameness might reduce the number of these cells and affect traits associated with domestication syndrome

Answer 93

- Hunting behaviour - alone or in groups - is a component of phenotype (observable property) as a result of genotype - In the theoretical past, individuals that hunted in packs got more meat on average than those who hunted alone - Dogs who ate more could produce more offspring - Offspring would also like to hunt in groups - Trait increase in frequency over time

Answer 94

1. Variation in a trait → different varieties of a trait 2. Fitness consequences of the trait → varieties must affect reproductive success and/or longevity differently 3. Inheritable → trait can be passed down to the next generation

Answer 95

1. Mutation (any change in genetic structure) Addition and deletion - point mutations Base mutations - substitutions of nucleotides Silent mutations - base mutations with no amino acid changes 2. Genetic recombination In sexually reproducing organisms Chromosome pairs line up and cross over during cell division Random 3. Migration Nongenetic pathway New individuals arrive from other places

Answer 96

- If none, fitness differences cannot be passed on and naturally selected - Genetic transmission or cultural transmission - Narrow-sense heritability: measure of the proportion of variation in a trait that is due to additive genetic variance - Behavioural differences can be a result of genetic differences - Measured in heritability experiments

Answer 97

Truncation selection experiments allow us to measure narrow-sense heritability Truncate = cut off

Answer 98

1. Label mean as x0 2. Cut off population level variation by only allowing individuals with scores greater than some value to breed → score is labelled as x1 3. Label mean of offspring (generation 2) as x2

Answer 99

maximal amount we could expect natural selection to change approach scores if the score was a genetic variation upon which natural selection could act S = x1 - x0

Answer 100

how much truncation selection has changed approach scores across generations 1 and 2 R = x2 - x0

Answer 101

Heritability = R/S % of all variance in approach that is due to genetic variance upon which natural selection can act Low → 0.0-0.1 Moderate → 0.1-0.4 High → 0.4-1

Answer 102

- When narrow sense heritability is high, behavioural variation in offspring should match that of parents - Greater role of environmental variance in determining behaviour = lower narrow-sense heritability

Answer 103

- When parents/offspring raised in diff environments, still join similar group sizes = correlation not a function of habitat IF group size preference was due to parents and offspring living in the same environment, correlation would disappear when they moved to diff environments BUT the result was that group-size preference was heritable = parent-offspring regression - Put babies from small colonies in larger and vice-versa - Found individuals still favoured the group size of their parents (not their foster parents) - Shows narrow-sense heritability

Answer 104

→ indicator of genetic quality in that they have fared well in responding to changing conditions More asymmetry in stressful environments

Answer 105

- Either in low, moderate or high degeneration (damage/disturbedness) forest sites - Left and right tarsus bone asymmetry with more stressful environments - Can help conservationists identify populations at risk and help before it’s too late

Answer 106

The study of the evolution of social behaviour

Answer 107

- Favoured by natural selection - Not in the emotional or moral sense - Just because they increase reproductive success - Any allele that codes for a trait that increases fitness will increase in frequency - Genes produced appear to be selfish

Answer 108

- Waterfalls act as a barrier to predators, upstream weak predation, downstream high predation - Little gene flow between sites (up/down stream) - High predation sites guppies mature faster, produce smaller and more offspring, and channel lots of resources to reproduction Why? Predators are large enough that guppy size doesn’t matter, they can eat them all More offspring is hoping at least one will survive - Low predation sites have a single small fish predator (rivulus hartii) Why? If offspring are big enough they can survive these predators Natural selection favours producing fewer larger offspring that can quickly grow large enough to avoid the predation of R. hartii

Answer 109

shoaling (schooling=group cohesiveness) and predator inspection (tendency for individuals to move towards a predator to gain information)

Answer 110

- When guppies transferred from high to low areas and vice-versa, eventually converged the behaviour of the new group - When returned to original began to shift back Why? - Either natural selection maintained their behaviour regardless of where they went or - There was a slow shift in behaviour then a slow shift back - Shows natural selection can take a long time or a short time and can act on antipredatory behaviour

Answer 111

- Mole rat colonies have high within-colony relatedness - First vertebrates to display eusociality = extreme sociality (often seen in insects) - A reproductive division of labour in which individuals in certain castes reproduce and individuals in other castes do not. (queens and workers) - Overlapping generations, such that individuals of different generations are alive at the same time. - Communal care of the young. - Genetic relatives share copies of the same alleles - Natural selection favours cooperative and altruistic behaviour among kin than unrelated individuals - Relation up = cooperative and altruism up - Mole rats more related than any other non-inbred species 0.81 relatedness

Answer 112

Darwin had “two great laws” centred on 1. The conditions of existence - The living (biotic) and nonliving (abiotic) environment that sets the stage on which natural selection operates 2. Common ancestry

Answer 113

- Study common ancestry and evolutionary history, introduced by Ernst Haeckel - Helps explain why different species share a behaviour; because a common ancestor had it

Answer 114

- Branch tips = taxa - Splits at nodes - Common ancestors at the splitting or branching points - Root is the common lineage from which all species on the tree are derived - Drawn in either tree format or ladder format (doesn’t matter which)

Answer 115

Tools are not only used by humans (although we like to think so) These crows used barbed leaf tools from Pandanus trees and shrubs to extract prey from under tree bark Prey grab inserted twig or leaf Learn by watching older toolmakers Start with simple stripped twigs, then use hooked twigs, then branched twigs with whittled ends Safeguard their favourite tools for later use Usually use the left edges of leaves because they prefer to use their right eye and right side of their bill to make tools Why? Maybe their low predation and low competition let them have enough time to test these tools out and their long developmental period gave them time to teach their young

Answer 116

Measure some traits a. Either developmental (embryological), molecular, or behavioural b. Or number of related structures (ex. of bones), morphological or anatomical Homologies → a trait shared by two or more species because they share a common ancestor Homoplasies/analogies → a trait shared by two or more species because they evolved it independently, not due to a common ancestor (plastic = molded) - Oldest state of a trait is the the ancestral or primitive trait

Answer 117

- Many possible phylogenetic trees - all hypotheses - Pick the one that is the most parsimonious - Can use to make inferences about natural selection - Convergency vs. ancestral linkage

Answer 118

- collect information on a pair of traits in different animals to see if they often go together - If natural selection has favoured this pair of traits, they will often be together

Answer 119

- Because sleep may strengthen immune system because energy that is invested in our activities when we are awake can be diverted to boost the immune system during sleep - Sleeping longer can help recovery speed, help with antibody responses, and help us suffer less severe symptoms - Also correlates with larger amygdala size = improves memory Measure white blood cells which are related to immunity, use red blood cells and platelets as a control Found positive correlation between sleep and WBC count, negative correlation between sleep and parasites

Answer 120

- 400 families of fish, 20 000 species - telosts aka bony fish - Made phylogenetic tree using morphological and genetic/molecular data - There were found to be multiple origins of parental care (no parental to parental) - Aka the stepping stone model of no parental, paternal, biparental, maternal was false

Answer 121

- Males either have bright colours and the female will choose to mate with them - OR males are drab and mate by thrusting their gonopodium after approaching from behind - Using mitochondrial rRNA they looked at phylogeny - Gonopodial thrusting was determined to be the ancestral (primitive) state

Lectures pre M1 Flashcards

(146 cards)