UVic Biology 215 Midterm

KT boundary

extinction of Dinos and such, mesozoic era, 65 MYA

cenozoic

age of mammals 65 MYA - current

minimum viable population (MVP)

population size required to retain 90% of genetic variability after 200 years

MVP minimum number

2500

Minimum Viable Area (MVA)

minimum land area required to maintain genetic variation after 200 years

small amount of immigration per generation

allows persistence of genetic variability and increased survival

natural selection

non-random and differential reproduction of genotypes resulting in preservation of favourable variants

adaptation

any physiological, morphological or behavioural modification that enhances survival and reproductive success of an organism

anagenesis

changing adaptations over time

does not lead to species diversity

cladogenesis

the branching of lineage to form new species

usually occurs with geographical or genetic isolation

precambrian

earliest life 4-3.5 BYA

precambrian

multicellular, soft-bodied 1.5-1 BYA

palaeozoic

hard-bodied fossil deposits 500 MYA

palaeozoic-mesozoic boundary

greatest extinction ever 250 MYA

mesozoic

age of reptiles 250-65 MYA

foraging decisions

animals make choices from wide variety of foods

ecology

study of relationships, distribution and abundance of organisms in the environment

chromosomal locus

gene

monomorphic

both alleles the same for all members of the population (aa)

polymorphic

one or more individuals in a population have different alleles (ab)

homozygosity

The state of possessing two identical forms of a particular gene, one inherited from each parent.

heterozygosity

having different alleles at a gene locus

increased homozygosity

leads to increased juvenile mortality

reduced population size

results in increased inbreeding

increased inbreeding

results in increased homozygosity

optimal foraging theory (OFT)

predicts that an animal's feeding behavior will maximize energy gain and minimize energy expenditure and risk

optimizing choice of food

greatest net energy gain

abundance of food

quality of food depending on scarcity

sodium

major role in body fluid volume, acid-base balance, tissue pH, muscle function, nerve synapses

terrestrial plants

high calories, low in sodium, low moisture

aquatic plants

low calories, high in sodium, high moisture

move to coastal regions

compensate for sodium deficiency in winter

optimizing foraging time

concentrate activity in most productive patches

stay at patch until profitability falls equal to the average of all combined patches

maximized net energy gain

maximized slope

low risk of predation

less foraging

medium risk of predation

more foraging

high risk of predation

constant foraging

territoriality

exclusion of resource use by others through display, advertisement or active defence of an area

home range

the area over which an animal travels in search of food/mates/resources and which is not defended

intraspecific territoriality

between individuals of the same species

interspecific territoriality

between individuals of different species

asexual reproduction

genetically identical to parent

common in bacteria, plants, aquatic invertebrates

short lifespan, constant environment

predictor of asexual reproduction

parthenogenesis

Asexual reproduction in which females produce offspring from unfertilized eggs.

sexual reproduction

genes from both parents combine to form new genotype

dioecious

type of sexual reproduction

male and female organs on separate individuals

monoecious

type of sexual reproduction

male and female organs on same individual

hermaphrodite/bisexual

simultaneous hermaphrodite

both sets of reproductive organs at the same time

sequential hermaphrodite

male and female organs develop at different times

common in corral reef fish

mate choice by female

follow a general criteria

evaluating a nuptial gift

criteria for mate choice

males provide gift to female (resource, food, territory, foraging opportunity)

female determines quality of male based off characteristics of gift

dominating/strong male preference

criteria for mate choice

strongest male has best genes

handicapped male hypothesis

criteria for mate choice

expression of handicapped males

costly to produce and maintain

survival with handicap shows physical fitness to female

Zahavi

handicapped male hypothesis

parasite free male hypothesis

criteria for mate choice

shows susceptibility to disease

health shown by bright nuptial displays

better resistance to disease, better genes

Hamilton and Zuk

parasite free male hypothesis

symmetrical male hypothesis

criteria for mate choice

unsymmetrical, errors during embryonic development

more symmetric means better genes

display evaluation

criteria for mate choice

females evaluate quality, complexity, coordination of display

panmixis

unrestricted random mating

polygamy

multiple partners

polygyny

males mate with many females but females mate with very few males

female defence polygyny

individual males defend groups of females

resource defence polygyny

individual males defend resources which females seek out

polyandry

females mate with many males but males mate with very few females

females compete for males and defend resources, more brightly coloured than males

polyandry

monogamy

high fidelity to single partner

increased female fitness

maximized genetic quality and genetic variability of offspring

increased male fitness

maximized number of fertilized eggs

inbreeding avoidance

criteria for mate choice

avoid homozygosity

can detect kinship based on body odour (pheromones)

Major Histocompatibility Complex (MHC)

Group of genes that code for proteins found on the surfaces of cells that help the immune system recognize foreign substances.

advantages for group living

increased food search efficiency

increased capture efficiency

increased detection of predators

increased defence against predators

selfish herd theory (dilution effect)

Many eyes theory

increased detection of predators

selfish herd theory (dilution effect)

each individual is only looking out for themselves, smaller chance of a specific individual getting targeted if they're in a big group

disadvantages of group living

limited resources and resource depletion

increased transmission of parasites

conflicts/stress

life histories

set of rules and choices to an individuals schedule of reproduction

reproductive effort

part of life history of organisms

total allocations that an individual makes for reproduction

r-selected

reproduce early in life, have many offspring, unstable populations (boom/bust), usually short-lived

k-selected

reproduce later in life, have low number of offspring, stable populations, usually long-lived

frequency of reproduction

part of life history of organisms

occurrence of parental care

part of life history of organisms

uncommon in many invertebrates, fish, reptiles, amphibians

common in social insects, birds, small fish, all mammals

precocial

no parental care

altricial

lots of parental care

clutch/litter size in k-selected species

part of life history of organisms

clutch size

maximum number of young that parent can successfully raise without net reduction in future reproductive effort

David Lack

optimal clutch size

artificially enlarged clutch

reduced survival of chicks

reduced egg production as adults

reduced survival of parent

reduced egg production for parent the following year

age of first reproduction

part of life history of organisms

major variation

fish & plant fecundity (number of eggs)

positively correlated to body size

semelparous

single reproduction

iteroparous

repeated reproduction

dispersion

type of distribution

hyperdispersion

equidistant

ex. fish school, seabirds

random dispersion

individuals are distributed without respect to others

ex. wildebeest, beech clams, forest spiders

aggregated or clumped dispersion

most common type of dispersion

coarse grained aggregated or clumped dispersion

clumps separated by large areas

fine grained aggregated or clumped dispersion

clumps separated by short distances

major reasons for clumped distributions in plants

local differences in microhabitat (nutrients, moisture sunlight)

major reasons for clumped distributions in animals

resources are clumped

behaviour which facilitates grouping (social context, family groups, predator defence, shelter)

dispersal

movement of individuals away from the immediate environment of the place of birth

common in most species

leads to gene flow

dispersal

migration

mass directional movement of large number of individuals from one location to the next

ex. salmon, whales, wildebeest, monarch butterfly, birds