Four results of genetic drift in a small poopulation:
fixation
loss of genetic variation
increase in mildly harmful alleles
increased differences between populations
increased genetic variation
stabilizing selection
Prairie chickens showed what results of genetic drift:
decrease in genetic variation
increased differences from other populations
Gene flow can result in:
increased similarities between populations
introduction of new alleles
Mosquitoes in africa were an example of gene flow
are features of organisms that improve their ability to survive and reproduce.
Soapberry bugs and the goldenrain vine were an example of adaptive evolution natural selection disruptive selection( adaptive evolution, natural selection, disruptive selection ).
Clines Temperate zones Inter tropical convergence zones( Clines, Temperate zones, Inter tropical convergence zones ) are patterns of change in a characteristic pattern over a geographic region.
In drosophila, the AdHs gene is less functional in cold, so the frequency increases with latitude
Bentgrass at mine sites was an example of natural selection genetic drift sexual selection( natural selection, genetic drift, sexual selection ) overcoming gene flow
Constraints on natural selection:
evolutionary history
ecological trade offs
lack of genetic variation
environment
cline
Genetic drift Gene flow( Genetic drift, Gene flow ) can result in reproductive barriers, but gene flow genetic drift( gene flow, genetic drift ) can prevent this from happening.
One introduced species started a cascade of speciation in which example:
Maggot flies, wasps and apples
Planorbella and Ribeiroia
White-tailed deer and ticks
Examples of life history characteristics are
Amount and timing of reproduction
Age and size at sexual maturity
Survival and mortality rates
Diet
Clown fish have a size hierarchy to reduce conflict
Phenotypic plasticity was occurring in these species:
Evergreens in different climates
Spadefoot toads
Prairie hens
Aspen trees
Phenotypic plasticity may be a continuous limited random discrete( continuous, limited, random, discrete ) range of sizes, or may have discrete intervals, called morphs life history stages discrete intervals( morphs, life history stages, discrete intervals ).
C. elegans was used as an example of:
Pros and cons of asexual vs sexual reproduction
Phenotypic plasticity
Polyphenism
Semelparous Iteroparous Metamorphic( Semelparous, Iteroparous, Metamorphic ) species reproduce once in a lifetime, iteroparous semelparous polyphenic( iteroparous, semelparous, polyphenic ) species reproduce many times in a lifetime.
r- slection K-selection intrinsic selection( r- slection, K-selection, intrinsic selection ) is the growth strategy that is rapid and advantageous in new environments. K-selection r-selection intrinsic selection( K-selection, r-selection, intrinsic selection ) is the growth strategy that is slower and is valuable in high-density environments.
Low stress, low disturbance is best for ❌. High stress, low-disturbance is best for ❌ with ❌. Low stress, high disturbance is best for ❌, with ❌.
Lesser black-beaked gulls were an example of a tradeoff between clutch size and survival rate of offspring.
High adult survival rates would favour allocating energy to growth reproduction( growth, reproduction ).
The Nassau grouper's change from being small and living in algae clumps to being larger and living in rocky areas is an example of a morph.
An adult mole salamander living in aquatic environments is an example of paedomorphism niche shift a morph( paedomorphism, niche shift, a morph ).
A ❌ cause is how the behaviour occurs, an ❌ cause is the evolutionary reason behind the behaviour. The ❌ is more interesting to biologists.
Cockroaches gaining an aversion to glucose after generations of exposure to an insecticide trap containing glucose is an example of:
adaptive behavioural change
evolution
niche shift
Old field mouse and deer mouse case study found that tunnel length is controlled by one loci two loci behaviour( one loci, two loci, behaviour ).
P= E/t is an equation relevant to:
foraging theory
herbivory
competition
carrying capacity
Handling time refers to how long it takes a parent to bring offspring to maturity.
Marginal value theorem states that an animal should stay in a patch until energy gain declines increases( declines, increases ) to average energy gain for the habitat.
Individuals from a single fertilization are a
genet
genetic
peanut
Regular Clumped Random( Regular, Clumped, Random ) dispersion can be the result of competition. Co-operative breeding can occur in high value low value( high value, low value ) habitats, when high quality low quality( high quality, low quality ) habitat is rare.
N= (M*C)/R is the equation for line transect abundance
Relative population size compares number of sightings in an area to effort or another area. Considered to model actual population
lambda= Nt+1/Nt is the equation for growth rate
❌ growth has a constant growth rate at ❌ periods, Nt+1= lambda(Nt). ❌ growth has ❌ reproduction dN/dt= rN.
Density independent factors regulate population size.
The logistic equation is
Nt+1=lambda(N)
dN/dt= rN
dN/dt= rN(1-(N/K)
Demographic stochasticity
chance events affect reproduction and survival
finite increase decreases as the carrying capacity is approached
cyclic events affect an individuals survival rate
❌- when chance event move the individual away from the norm while birth and death rates remain constant. ❌-changes in environment cause change in birth and death rates. ❌- small populations have decreased growth as it becomes harder to find a mate.
Metapopulation is an analysis of all populations in an environment
Amensalism is where one species is harmed and the other is ❌.
This is the equation for the
Lotka-volterra competition model
logistic growth
This is the range where species can co-exist
Character displacement is where
through competition like species diverge
natural selection causes directional selection
competition drives one species to extinction
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