Chippendale Flashcards

Question

What can H-W equation be used for?

Answer 1

If at equilibrium... - to approximate allele freqs. of interest - determine if the population is at equilibrium If not at equilibrium... - count allele/gene freqs. - calculate expected genotype freqs. - compare observed number w/ expected number

Answer 2

1. Evolution can be explained using genetic mechanisms/observations 2. Adaptation occurs via graded/gradual change in genetic freqs./phenotypes 3. Natural selection upon phenotypes = major driving source for adaptation 4. There must be variation among individuals for evolution 5. Microevolution processes are sufficient to explain macroevolution

Answer 3

- amount of which a trait depends on genetic influence - correlation between parents and offspring estimates heritability - don't follow Mendelian genetics (blending)

Answer 4

- populations are finite in size, meaning that gene freqs. can change from pure "sampling error" - drift most profoundly affects small populations

Answer 5

- when a new population is established by a small # of colonists, it can skew genetic freqs.

Answer 6

- large populations subject to dramatic decrease in size, remaining individuals repopulate but lower genetic variation than before

Answer 7

1. Directional selection: favours 1 of the 2 extreme phenotypes 2. Stabilizing selection: favours intermediate phenotype 3. Disruptive selection: favours extreme phenotype 4. Balancing selection: maintains genetic diversity

Answer 8

a) males compete with each other | b) females actively select the best mate

Answer 9

Inbreeding → Small Population Size → Exposes Deletrious Recessives → Fitness Reduced

Answer 10

- male and females are paired for at least one reproductive cycle - can be explained by... - male guarding: prevent females from being fertilized by another male - male assistance: help to rear offspring - female-enforced monogamy: females make males stay

Answer 11

- one male mates with many females - resource based polygyny: some males dominate resources and mate with visiting females - communal courting: males all congregate and perform mating displays, then females choose

Answer 12

- one female mates with many males | - only limited by the amount of males she can find to incubate her eggs

Answer 13

- meadow voles are promiscuous + don't parent - prairie voles are monogamous and co-parent - attributed to vasopressin and oxytocin - prairie voles have more receptors for these hormones

Answer 14

- formation of a new species | - no gene flow can lead to divergence and evolutionary adaptations

Answer 15

- when certain characteristics are favoured by evolution due to their appeal to the opposite sex - sometimes seems to contradict NS (e.g male peacock feathers make it hard to escape predators) - based on the idea not every male will get to "sow his seed" - leads to sexual dimorphisms

Answer 16

The fitness of a phenotype decreases as it becomes more common

Answer 17

The fitness of a phenotype increases as it becomes more common

Answer 18

The retention of juvenile traits in adults

Answer 19

Something grows rapidly/more in comparison to the rest of the body

Answer 20

Something grows slowly/less in comparison to the rest of the body

Answer 21

Geographic barriers isolate a population into 2+ groups, which over time may develop to become a separate species - genetic drift and adaptation to local environment may perpetuate this divergence

Answer 22

Differentiation that occurs in a population without geographic isolation - caused by major genetic changes that quickly create reproductive isolations - e.g. change in the number of chromosome

Answer 23

Differentiation of a single species into a multitude of different species - often due to new environmental or physiological feature - multiple species radiating from one common ancestor

Answer 24

domain→ kingdom → phylum → class → order → family → genus → species

Answer 25

- tracks the differentiation of species from a common ancestor - done using homologies (common structure/genetic similarity) - e.g. phylogenetic trees

Answer 26

The study of the interactions between organisms and their respective environment

Answer 27

The study of changes in the number of organisms within a population over time and space

Answer 28

A form of quantitative characterization of a population over space - # of individuals/unit space

Answer 29

A form of qualitative characterization of a population over space - distribution of a population within an allotted space

Answer 30

1. Clumped - e.g. pack animals (wolves) 2. Uniform - e.g. penguin nests are spread out evenly 3. Random - e.g. plants

Answer 31

1. Natality/birth rate (b) 2. Mortality/death rate (d) 3. Immigration (i) 4. Emigration (e)

Answer 32

The rate at which a population increases per capita - growth rate = birth rate - death rate - r = (b-d) + (i-e)

Answer 33

In most sexual species, one mating type produces large, nitrified gametes, whilst the other makes small gametes virtually devoid of cytoplasm

Answer 34

- Flu virus type A, B or C - Type A = most mutable - Antigenic drift = caused by mutation leading to changing proteins on surface - Antigenic shift = caused by recombination between strains - Both shift and drift make vaccines problematic/imperfect (must be based off of probabilistic estimations)

Answer 35

* ** Pybus et al. 2015 - used phylogenetic methods to assess relatedness, shows how seasonal flus evolved over a 6 year period - the colours of the branches reflect the match of DNA sequence to regional frequency: the virus diverges evolutionarily as it spreads globally. - Flu usually comes from Asia - the main trunk of phylogenetic tree that carries the virus along over time is predominantly Asian, reflecting the epicentre of seasonal flu ancestry.

Answer 36

- First identified in Zika forest in Uganda at virus research centre - Arbovirus (arthopod borne virus) - Zika virus is spreading rapidly out from a narrow equatorial band - Has been linked to microcephaly (small brain) in child development and Guillain-Barré syndrome - Involves as many as 8 recessive genes affecting brain growth

Answer 37

- 1918/1919 pandemic flu (characterized by seasonal waves) - Kills estimated 50-100 million people, sometimes within hours of infection - Mortality rate of 15-34 year olds 20x higher than any flu epidemic known - Killed itself off (ran its course) - Age distribution of mortality differs between highly virulent pandemic strains of flu and seasonal flu - This is partially due to evolving nature of immune response through our lives with age - Risk (for pandemic strains) tends to grow with increasing intensity of immune response (unlike seasonal flu).

Answer 38

- H1N1 (avian flu) = strain of influenza virus A - Negative sense, single-stranded, segmented RNA virus - Limited human-human transmission (no evidence of recombination with human strains) - Also limited human resistance and widespread endemic population in birds in Asia - High rate of mortality - Huge threat if it mutates

Answer 39

- Bugs feeding apparatus changed when the bugs transitioned from balloon vine fruit to flat-podded golden rain fruit - When the bugs were taken to the lab, the change persisted. - This means the change was an adaptation and not phenotypic plasticity - Also evidence of rapid evolution

Answer 40

- Field caught guppies were brought into artificial streams in the greenhouse - Measured male spots (number, size, colour) according to experiment treatment - Male spot number: increased in control/low predator treatments, decreased in high predator treatment - Most visible colours (blue & iridescent) went down sharply in the high predator treatment - Spot size/colour also shifted towards matching gravel under high predation

Answer 41

- Endler found a part of a tributary where guppies were absent above a barrier waterfall - General conditions were similar to a lower location containing predators - He caught and moved a sample of 200 guppies upstream - Guppies got sexier (more spots, more colour) after about 15 generations

Answer 42

- 12 clone populations - New beneficial mutations occurred randomly in all 12 lines - Fitness increased over the first 20 000 generations: the E. coli had “tried out” every point mutation possible - A number of lines became mutators and had elevated rates of spontaneous mutations (new adaptation occurred in occasional jumps - After generation 33,000 population A3 exhibited a sudden increase in fitness - A key innovation had arisen - Conclusion: E. coli were unable to aerobically metabolize citrate but with one mutation they were able to - Mutations can be beneficial and lead to evolution/adaptation

Answer 43

1. Strength of Selection - did a small or large proportion of individuals reproduce? 2. Heritability of Variation - small/large fraction of variation seen underpinned by genes whose effects will be expressed in the phenotype of the offspring

Answer 44

- Showed that fossil record shows a consistent rate of extinction at species and family levels of organization; past success does not predict future survival. - Proposed that pressure from evolving competitors and enemies (parasites, predators) means that no organism is ever completely “adapted”. - Much of evolution is an "arms race" with other evolving organisms - Sexual snails are only found in the shallow waters of lakes where parasites are abundant due to the presence of their primary host: ducks - The trematode larvae grow in the snail gonads, sterilizing the host, but sexual snails are different enough that the parasite won’t kill them all - Where sexual and asexual forms of the same organism coexist, asexuals harbour more parasites - Genetic change in a population is necessary to maintain the status quo - Frequencies of asexual hosts increase (hills) and decrease (valleys) in response to parasite adaptation, while sexual hosts can avoid these coevolutionary ups and downs.

Answer 45

* * founder effect - 50% of current 2.5 million population have 20 names traceable to that ship - 1/3 white south Africans from 40 founders - Huntington’s disease is abnormally high

Answer 46

- Population was not genetically diverse and approaching extinction - Strategies used to recovery habitat were largely unsuccessful - Importation of stock from neighbouring states led to dramatic reversal - Gene flow can go a long way - Conservation also need to be cognizant of the breeding system and effective population size

Answer 47

- Promiscuous species that typically exist in large populations - Male fruit flies exert a harming effect upon females through (persistent harassment, mechanical wounding, and chemical properties of the seminal fluid) - Monogamy reduced sexual conflict - Seminal Fluid Proteins: diverse antimicrobial functions, stimulate egg production, increase oviposition rate, decrease sexual receptivity, decrease female attractiveness, help transport and store sperm, release rival sperm from storage, form mating plug, reduce female longevity

Answer 48

- Rice showed that when males were allowed to adapt to courting and mating with a certain type of female that could not change (fixed genotype): - Male fitness increased through greater mating success and higher success rate in sperm competition. - Females kept with these males died much more rapidly from toxic side effects of the seminal fluid.

Answer 49

- Dioecious and sexually dimorphic - Females have few, larger flowers - Males have many, smaller flowers - High levels of additive genetic variation for flower number and size

Answer 50

- Over 10,000 people who graduated from Wisconsin high schools were tracker over 50 years - Looked at brother sister pairs - Shorter woman had more kids than taller woman - Average height men had the most offspring

Answer 51

- Female relative of gay men have higher fertility than female relatives of straight men - Fitness costs of homosexuality recovered opposite sex relatives - Effect matrilineal, implying X-chromosome linkage - The results were replicated including gay woman in reverse

Answer 52

- Female relative of gay men have higher fertility than female relatives of straight men - Fitness costs of homosexuality recovered opposite sex relatives - Effect matrilineal, implying X-chromosome linkage - The results were replicated including gay woman in reverse

Answer 53

- Measured relationship between # of mating and reproductive success in drosophila - Finding: The variance in male fitness is higher than the variance in female fitness - Males show undiscriminating eagerness - Females show discriminating passivity - Explanation: Sperm is cheap to produce therefore males can mate with many females - Female offspring is limited so they have to invest more energy

Answer 54

- When females tend the offspring, males tend to be showier and perform aerobatic displays - When males tend the offspring, the females tend to be larger, more colourful and more aggressive - If males are going to care for the offspring and males are limited, a female may need to convince several males to accept her eggs - Males will be choosey - He wants to make sure he is the father of the kin his is rearing - Investing energy in rearing another male’s kin is worse than not mating at all

Answer 55

- Female grey tree frogs prefer males that have longer and more complex calls - Females respond to male calls doing more complex calls - Complex signal: puts the male in danger, costs them to make it

Answer 56

- Some studies show that female guppies prefer male with strong orange colouration - Good genes: If the bright colouration signals ability evade predators to find rare carotenoid pigments in the diet or is difficult to produce it could be an indicator of genetic quality - Sensory exploitation: Females seek orange food items and they are tuned to be finding orange fruit so orange guppies stand out - Negative frequency dependence (rare male advantage) helps avoid inbreeding - Guppy males have at least two distinctive mating strategies: 1. Colourful Displays 2. Sneak copulation is an alternative mating strategy maintained by negative frequency dependence (If a male can thrust his gonopodium into a females gonopore then he may be able to latch on and inseminate)

Answer 57

- Three colour morphs correspond to genetically mediated behavioural mating strategies - Orange: Ultra dominant, polygynous, territorial - Blue: Monogamous, territorial - Yellow: sneaker drifter - Orange beats Blue , Blue beats Yellow, Yellow beats Orange - A cycle is created where the least common morph of one breeding season often has the largest number of mature living offspring in the next year (frequency dependant selection)

Answer 58

- Male finches artificially ornamented with leg band jewelry had higher pairing success. - Females that pair with them have lower rates of extra pair copulation and provide more nest care for young. - Ornamented males reduce nest care and solicit EPCs. - Females mated to ornamented males invest more energy and testosterone in male eggs, and bias their clutches towards sons

Answer 59

- Opened awareness of post-copulatory sexual selection - Early models saw sperm competition as a numbers game - Relative testis size is a good predictor of the intensity of sperm competition - Analysis of the reproductive systems of a number of organisms has revealed enormous complexity - Models have had to accommodate this extraordinary potential for extended male-male and female-male interactions after mating

Answer 60

- Back swimming beetles, some ostracods, the painters frog an Australian land snail known for really big sperm - Record help by drosophila bifurca - 58mm sperm are over 20x male body length slow maturation (17d), incredibly low number transferred

Answer 61

- Ring Species: Greenish Warblers - Pattern points to southerly origin, and have evolved to move northern - Southern range: at a higher elevation - Species does not hybridize (breed with each other) = prezygotic isolation - As birds expanded range, their songs are very complex - Females don’t like the males’ songs from the other group - Continuous variation around the plateau

Answer 62

– territorial – adaptable, particularly in mouthparts (pharyngeal jaws (extra set of crushing plates in throat) – strong mate choice (strong chromatic ornamentation allows both mate choice and species discrimination) – many reproductive strategies • cooperative breeders (nesters, moothbrooders) • free spawners • many strategies in between

Answer 63

- Bathymetrically fragmented: deep and anoxic below 250m (west and east side are very separated b/c of the deep lake and they don’t move a lot - Habitat fragmented: cobble, boulder, sandy habitats may be interspersed by small coves

Answer 64

- Salticid spider found widely in the American SW (desertification has fragmented range leading isolated populations living at high altitudes - Males on these sky islands vary markedly in ornamentation, drumming song and other courtship behaviours - Females look the same and DNA shows little evidence of divergence between populations - Suggests little naturally selected divergence or drift but very rapid divergence in sexual signals

Answer 65

- Major crop pest (have made a host shift from native hawthorn fruit to introduced apple fruit - Strongly differentiated at marker loci by electrophoresis - Mate on the fruit, suggesting that host-specialization reinforces reproductive isolation - Display strong host-specificity when offered a choice - Gene flow still easily possible (host plants coexist in close proximity, flues fly) but most hybrids probably die) - Prezygotic isolating mechanisms will reinforce postzygotic isolation - Hawthord fruit ripen in fall, apples ripen early - If a fly pupates too early it may wake up before winter and perish; too late it isn’t ready - Flies on hawthorn must develop rapidly to pupate and diapause before the frost - Flies on apple develop slowly so they can time diapause to winter - Hybrids don’t do well because the system goes from warm to cold weather - Hawthorns blood later than apples but rhagoletis needs to dispose at a specific time - But if it gets into the apple it will have a slower developmental program - But if it goes into an hawthorn it will have to mature to fast - If you have hybrid then you will dispose to early in apple and to late in hawthorn because the time period is in between the two

Answer 66

- Heterochronic changes provides a potential mechanism for rapid evolution of whole body forms via growth allometry - Provides mechanism for some views of rapid/punctuated evolutionary change - Associated with leaps in evolution that skips over gradual change - We retain many of the juvenile stages from our parents

Answer 67

- Chimp cranial development deviates from human cranial development by: strong negative allometry of brain case, strong positive allometry of the jaws and brow ridges - Strong positive allometry for relative brain size: selection on intelligence or byproduct of neotony - MYH16: Inactivation results in smaller jaw muscles, may have facilitated evolution of language, related to food manipulation and cooking??

Answer 68

- The bithorax complex includes Ubx, a gene which, if mutated, can specify an extra set of wings in a dipteran fly - Used mutagenesis to study segmental development in flies - Work would lead to the discovery of the Hox complex - Suggests deep homologies eg. Complex protostome/deuterostome common ancestor

Answer 69

- Royal Albatross: - Raises a small amount of offspring - More expensive - Fruit Fly - Very quick reproductive cycle - Explosive reproductive output - Output is huge but success may be low - Two animals are using different life history strategies: - The fly (r-selected) is adapted to exploit available resources with explosive reproductive output; mortality rates are very high with few surviving to reproduce - The albatross (k-selected) is adapted to reproduce slowly, with a high rate of survival - Life history strategies are constrained by trade-offs: Investing energy into reproduction may lead to reduction in survival probability - Tradeoffs occur in individual lives but are also characteristic of species - Virgin female flies may live 20% longer but they don’t live forver

Answer 70

- Because there is a cost to reproduction, organisms employ widely varied energy allocation strategies. - semelparous (reproduce once) organisms like salmon or Antechinus (small marsupials) invest in a terminal reproductive strategy. - iteroparous (reproduce many times) organisms like the eider duck (above) breed over over multiple rounds.

Answer 71

- Employ a terminal investment strategy with male living just one year - Reallocation of resources to sperm and semen production, mate guarding via extreme copulation duration and female hyperpolyandry lead to massive physiological collapse

Answer 72

- Hare cycling is a classic example in population dynamics: - As hare populations expand, their predators (fox, wolf, lynx) grow too → this drives down the hare populations with predators collapsing slightly out of phase - Most of the change is due to predation directly but other changes possible → hare females get stressed out by the presence of predators and produce fewer offspring/more still born offspring

Answer 73

- One from is cryptic whereas the other is aposematic - Aposematic species pack a potent deterrent such as a toxin - Palatable Batesian mimics use aposematic colours but lack the actual defences: their fitness will be negatively frequency dependant, too common and the predator does not learn avoidance - Mullerian mimicry where model and mimic are dangerous is a form of convergent evolution where there may be positive frequency dependence - Cryptic = camouflage

Answer 74

- Plants may not be able to run, but they can protect themselves - Spines and thorns, thick bark offer some physical protection - Chemical defences are also common, including numerous poisons, insecticides and distasteful compounds - Many herbs and spices are flavourful because of plant defence compounds - Fruit are difference: many are sweet and delicious because they want to be eaten

Answer 75

- The capsaicin that makes a pepper hot is a chemical protectant - The number one cause of seed death is a fungus called fusarium - Fusarium enters the fruit through wounds caused by insect herbivores - Capsaicin kills microbes and deters insects as well as mammals - Birds don’t have receptors for capsaicin and eat the ripe chili fruit dispersing the seeds - But capsaicin is complex and expensive to produce - A trade off between seed quality and protection is apparent: - Pepper plants are polymorphic for pungency - Where the insect wounding/fungus is uncommon, peppers tend to be mild - Mild peppers are larger and have thicker, studier seeds

Answer 76

- The ants lack invertase expression - The tree provides the enzyme in nectar - The tree also produces chitinases that permanently disable invertase