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Exam 5 - Coggle Diagram

- - - - Population size (N)
      - Exponential growth
        
        J-shaped curve
        
        Unlimited resources
      - Logistic growth
        
        S-shaped curve
        
        Typical of a population that
        
        self regulates
        
        Has a carrying capacity (K)
    - - Overshoot K
      - Result in die off
      - Limited resources
    - - r = intrinsic growth rate
      - N = population size
      - K = carrying capacity
      - dN/dt = population change over time
      - Exponential growth
        
        dN over dt equals r times N
      - Logistic growth
        
        dN over dt equals r times N times the quantity one minus N divided by K
        
        Use logistic growth to predict the two interacting species
    - - Exponential growth
        
        dN/dt = rN
      - Logistic growth
        
        dN/dt = rN[(K-N)/K] = rN(1-N/K)
    - - r-selected
        
        Grow exponentially
        
        Disturbed areas
        
        Weedy
        
        Annuals
        
        Little investment in defense
        
        Many, small fruits
      - K-selected
        
        Fluctuate around carrying capacity
        
        Fairly stable habitats
        
        Perennials
        
        Invest in defenses
        
        Resource-intensive fruits
    - - Plants must make trade-offs due to environmental necessities
      - Many strategies exist
      - Grime’s model
        
        Stress
        
        Resource availability
        
        Water
        
        Nutrients
        
        Light
        
        Growth inhibitors
        
        Temperature
        
        Toxins
        
        Disturbance
        
        Biotic
        
        Herbivory
        
        Pathogens
        
        Anthropogenic
        
        Abiotic
        
        Fire
        
        Wind
        
        3 life stages
        
        C- competitors
        
        S- stress tolerators
        
        R- ruderals
  - - - Life tables summarize birth and death rates for organisms at different stages of their lives.
        
        Population age structure—Are there lots of: young individuals? Old individuals? Reproductive age individuals?; and similar questions
        
        Population growth rate—How fast is the population size growing (or shrinking)? Population survivorship patterns—Does most mortality occur in the very young? The very old? Or equally across all ages?
    - - x = age
      - Nx= number of individuals alive at age x
      - Sx= proportion of individuals of age x that survive to age x+1;
        
        Nx+1/Nx
      - lx= proportion of individuals that survive from birth (age 0) to age x;
        
        Nx/N0
      - Fx= average number of offspring born to a female while she is age x
      - lx(Fx) = average number of offspring per capita at age x
      - lx(Fx)x = average number of offspring per capita at time x, weighted by age x
    - - Calculate the net reproductive rate (R0)
      - Calculated by taking the sum of the offspring/individual column.
      - Represents the expected number of offspring an individual will produce over its lifetime in the population.
        
        If R0>1, the population size increases.
        
        If R0<1, the population size decreases, and
        
        if R0=1, then population size does not change.
    - - Calculate the mean generation time (G)
      - Calculated by taking the sum of the Age-weighted fecundity column and then dividing by the net reproductive rate
      - Represents average time between two consecutive generations in the lineage of a cohort
      - The average age between parent and offspring
      - For humans, typically 20-35 years of age
    - - Calculate the intrinsic growth rate (r)
      - Calculated by taking the natural log of the net reproductive rate divided by the mean generation time.
        
        If r>0, the population size increases.
        
        If r<0, the population size decreases, and
        
        if r=1, then population size does not change.
    - - How long did individuals survive
      - Visual representation of survivorship
      - Type I, typical of K-selected species
      - Type III, typical of r-selected species
      - Dependent on environment
      - Same species can display all 3
    - - Survivorship curves are plotted logarithmically
      - Take survivorship (lx) and multiply by 1000
      - Take the log10 of this value
      - Plot against age to produce a figure
      - Example: Type I curve
  - - - a group of actually or potentially interacting species living in the same location.
      - bound together by a shared environment and a network of influence each species has on the other.
      - factors affecting interactions include
        
        abiotic environment
        
        biotic interactions that occur between species
    - - Range of interactions
      - Beneficial interactions +
      - Negative interaction -
      - Facilitation (+/+)
        
        Benefits both
        
        Mutualism
        
        Pollination
      - Commensalism (0/+)
        
        Benefits one, neutral to the other
      - Amensalism (0/-)
        
        Negative to one & neutral to other
      - Competition (-/-)
        
        Both are negatively impacted
        
        Competition for resources
      - Predation (+/-)
        
        Herbivory
        
        Parasitism
    - - Predator
        
        P
        
        Negative impact on prey
        
        Positively impacted by prey
      - Prey
        
        N
        
        Positive impact on predator
        
        Negatively impacted by predator
      - Population sizes are influenced by each other
    - - r = intrinsic growth rate
      - N = population size
      - K = carrying capacity
      - dN/dt = population change over time
      - Exponential growth
      - Logistic growth
      - Can similar model predator-prey growth and the impact each has on the other
    - - At low prey and predator population sizes, prey increase exponentially
      - As more food for predators is available, predator survival and reproductive success increases, resulting in predator population growth following that of their prey
      - As predator populations increase, prey death rate exceeds birth rate, resulting in prey decline
      - As prey number declines, there is not enough food to sustain a high predator population and thus predator death rate exceeds that of birth rate
    - - dN/dt = rN-aNP
        
        dN/dt=rate of change with time of the prey population
        
        r=intrinsic rate of increase for prey
        
        N=number of prey individuals
        
        a=predator’s per capita attack rate
        
        Number of prey eaten per predator per unit time
        
        P= number of predator individuals
      - dP/dt = faNP-qP
        
        dP/dt= rate of change with time of predator population
        
        f=constant, indicating predator’s efficiency at converting the prey it has eaten into new predators
        
        q=predator’s per capita mortality rate
- - - - All of the alleles of every gene in a population make up the gene pool
      - A population is a group of individuals of the same species that occupy the same region and can interbreed with each other
    - - Allele Frequency: Number of copies of an allele in a population divided by the total number of alleles for that gene in a population
      - Genotype Frequency: Number of individuals with a particular genotype in a population divided by the total number of individuals in a population
    - - No new mutations
      - No genetic drift. The population is so large allele frequencies do not change due to random sampling effects
      - No migration
      - No natural selection
      - Random mating
    - - All alleles in the population add up to 100% or 1
      - All genotypes in the population add up to 100% or 1
    - - The frequency of gametes carrying a particular allele is equal to the allele frequency for a population in Hardy-Weinberg equilibrium.
      - Multiplying the allele frequencies gives the proportion of each allele combination in the population.
    - - p+q=1
      - p2+2pq+q2=1
        
        p2= genotypic frequency of RR
        
        2pq= genotypic frequency of Rr
        
        q2= genotypic frequency of rr
      - The frequency of the dominant allele is represented by p
      - The frequency of the recessive allele is represented by q
  - - - Changes in a population’s gene pool from generation to generation
      - Factors
        
        Mutation
        
        Change in one of the nucleic acids
        
        Some are apparent in phenotype
        
        Source of all new alleles
        
        Must be in gametes to be inherited
        
        Male pollen sperm
        
        Female ovule egg
        
        Natural selection
        
        One allele selectively advantageous
        
        Over time, individuals with the 2 genotype are able to reproduce more and grow in numbers
        
        The overall vigor of the population grows
        
        So does population size
        
        Artificial selection
        
        Selection by humans
        
        Increased frequency of desired trait
        
        Elimination of undesired traits
        
        Crop breeders for thousands of years
        
        Example Brassica
        
        Genetic drift
        
        Random loss of alleles
        
        Acts most strongly in small populations relative to large
        
        Bottleneck effect
        
        Large population diminished suddenly
        
        Natural catastrophe
        
        Migration
        
        May increase in size again but unlikely to regain original diversity
        
        Migration
        
        Movement of alleles into and out of a population
        
        Immigration
        
        Emigration
        
        Can be impeded by
        
        The environment
        
        Life history
        
        Repercussions for
        
        GMO and climate change
        
        Speciation
        
        Adaptive radiation
        
        Bottleneck from long distance dispersal
        
        Followed by adaptive radiation
        
        Example: Hawaiian lobeliads
        
        Nonrandom mating
        
        Plants “choose” their mates
        
        Pollinator vectors
        
        Pollination syndromes
        
        Some of the individuals reproduce more than others
        
        Based on individual phenotypes
        
        Sexual selection
        
        Male-male competition
        
        Excess of pollen grains
        
        Pollen tubes can interfere with one another
        
        Female choice
        
        Barriers on stigma surface preventing germination
      - Microevolution goes against HW assumptions
    - - Dimorphic
        
        2 phenotypes
        
        Dominant-recessive systems
      - Polymorph = many phenotypes in a population
      - Example: Aquilegia
        
        Color variation
        
        Spur-length variation
      - Can be due to a single nucleotide polymorphism
  - - - Steps
        
        Find your Min & Max values
        
        Determine the number of bins
        
        Count the number of observations for each bin
        
        Draw bars for each bin with the frequency
    - - Death does not mean natural selection has occurred
      - Differential survival
      - Survival due to phenotypes that are heritable
      - Phenotype coded by genotype
    - - Within a population there is allelic variation arising from various factors such as mutations causing differences in DNA sequences
      - Distinct alleles may encode proteins of differing functions
      - Some alleles may encode proteins that enhance an individual’s survival or reproductive capacity
      - Individuals with beneficial alleles are more likely to survive and reproduce
      - Over the course of many generations, allele frequencies of many different genes may change through natural selection
      - This significantly alters the characteristics of a species
      - Natural selection may affect allele frequency