Midterm #1 Flashcards
Polymorphic
One or more variants at a locus within a population
Minimum Viable Population
Population size needed to retain 90% of genetic variability after 200 years
Minimum Viable Area
Minimum area size needed to maintain genetic variability after 200 years
Anangensis
gradual change over geological time. Changing adaptations over time
Cladogensis
the branching of lineages and formation of new species
Geological Timetable (7)
First Unicellular Life -- 3.5 BYA Multicellular Soft Bodied -- 1 BYA Hardbody fossil deposits -- 800 MYA Age of Fishes -- Paleozoic (540-250) MYA Greatest Extinction Event -- 250 MYA Age of Reptiles -- Mesozoic (250-65) MYA Age of Mammals -- Cenozoic (65 MYA - Present)
K/T Boundary
A geological signature within the rock that shows the distinction between the cretaceous and tertiary periods
Optimal Foraging Theory
Preference for food/prey with greatest NET energy gain
Feed more selectively when food/prey is abundant
Include low quality food/prey only when food/prey is scarce
Patch Foraging Rules
Concentrate foraging on most productive patches, ignore patches of low productivity
Stay within patch until productivity falls to a level equal to the average of all patches combined
Best Predictor of Asexual Reproduction in Animals
Constant environment and short lifespan
Panmixis
Unrestricted random mating, all individuals of the opposite sex are potential mates
Most schooling fishes and marine invertebrates
Usually monomorphic
Dominant/Strong Male Preference
Females will often flock to the strongest male in the area for protection and exclusively mate with this male
Parasite-free Male Hypothesis
Individuals differ in their ability to contract pathogens
Resistance to disease is a heritable trait, and males with no parasites have better immunological genes and physiology
Hypothesize that bright colours are costly to produce so can only be produced by parasite-free males
Hamilton and Zuk only have partial support for this
Symmetrical Male Hypothesis
Minor errors during development cause asymmetries in the animal
Excellent genotypes can correct these errors so females choose symmetrical males as they have better genotypes
Good support in the literature
Inbreeding Avoidance
All plants/animals have a mechanism to prevent inbreeding (homozygosity)
Mostly done by ~30 genes for special proteins in the cell membrane for major histocompatibility complex (MHC) Used to detect pheromones about relatedness,prefer males that smell most dissimilar to them
Advantages of Group Living (5)
Increased food search efficiency, Increased capture efficiency, Increased detection of predators (many eyes hypothesis), Increased defence against predators, Selfish-herd theory (dilution effect)
Disadvantages of Group Living (3)
Shared resources and resource depletion, Increased transmission of parasites and conflicts/stress
R-Selected
high numbers of eggs, high population growth potential, boom or bust cycle, maximum reproductive capacity (r)
K-Selected
low numbers of eggs, low population growth potential, stable populations, usually long-lived, populations near carrying capacity (K)
Semelparous
Single reproduction event (insects, cephalopods, salmon)
Iteroparous
Repeated reproduction events (plants, molluscs, fish, Vertebrata)
Precocial Young
Offspring that soon after birth are capable of fending for themselves
Altricial Young
Offspring who are born relatively helpless to their environment
David Lack
Proposed that number of eggs in bird clutch size represents the maximum number of young that the parent and successfully raise
Generation Time
Age at which organisms are able to reproduce
Geographical Distribution (3)
Cosmopolitan: Spread to everywhere in one medium (all oceans, countries, etc)
Limited: These species are limited to large areas depending on the climate
High restricted (endemic): Only exist in a single place on earth
Types of Distribution (3)
Hyperdispersion: equidistant tightly packed (school of fish, seabirds)
Random: individuals are randomly distributed without respect to each other (grazing wildebeests, clams, forest spiders)
Aggregated: individuals form groups separated from each other – Coarse (clumps separated by large area) or fine (clumps separated by small area)
Peterson/Lincoln Index for mark,release,recapture
Live capture – mark and release
N=population size, M=# of marked individuals in a population
Resample population
n=# of individuals in the sample, m=# of the marked individual in the sample
M/N=m/n
Assumptions for mark-recapture studies (4)
The population is mostly constant (no immigration, emigration, births, deaths
Marked individuals have the same chance of being caught
Marked individuals do not incur greater mortality (stress-related or mark associated)
Marked individuals do not lose their marks
Age-specific Cohort Analysis
Follow a specific cohort from birth (hatching) to death
Most useful on short-lived species
Time-specific life table
Age structure at a single point in time
Long-lived animals (most large animals)
A snapshot in time (static life table)
Requires age distribution of a population
Survivorship formula
lx = Ntx / Nt
Mortality Formula
qtx = (Ntx -Ntx+1) / Ntx
4 Primary Population Parameters
Birth, Death, Immigration and Emigration
Nt+1 = Nt + B + I – D – E
Age-specific Fecundity Rate (ASFR)
Average number offspring produced per female for each age group
Total Fecundity Rate (TFR)
The average number of offspring produced per female over her lifetime
Net Reproductive Rate (NRR) (R0)
Survivorship of reproductive females in any age group (lx) multiplied by the number of daughters produced for each age class of female (mx)
R0
The average number of breeding daughters that will be produced by each breeding female in the population in her lifetime
R0 <1 : Population is decreasing
R0=1 : Population is stationary
R0 >1 : Population is increasing
Geometric Growth
When a semelparous population grows without constraint
Nt+1 = R0*Nt
If net reproductive rate is unknown use Lambda
λ= Nt+1 / Nt
Estimate the geometric growth of population into the future
Useful for non-overlapping semelparous species
