Population Dynamics
What is a Biological Populations
A population is a group of individuals of the same species living in the same area
Population size is the number of individuals over time
Population Dynamics describes the fluctuations in population size- because of interactions between different species
Species Distributions
What limits species distributions
species are where they are because of evolution and ecological features
Dispersal is the movement of individuals or gametes from their place of orgin
Abiotic non-living
factors like temp water and sunlight can limit dispersal
Biotic(living) factors can also limit dispersal depending on competition
Population Density and Dispersion
density is the number of individuals in a unit area
Population dispersion is the pattern of spacing among individuals
individuals in specific patches -clumped
evenly spaced- uniform
scattered- random
Pattern vs Process
dispersion is explained by different factors
food
mating
success
uniform might be territorial defense of their space
Population Models
Research Approaches
Observations
Experiments
models - represent phenomena through concepts
changes in population
births add individuals to a population N goes up
delta N is change in population
Deaths decreases population N goes down
delta n = B-D
we divide n by time for specific time frame
Migration
immigration adds
emigration removes
(linking local populations) metapopulation - can ensure that if one one population goes extinct it can be recolonized
Exponential Growth Model (ugh math)
determine the individuals already in the population per captia r
over a certain time year annual
rN is how much a population is growing at a certain time
calculus yayyyy ☹.
Intrinsic rate of increase population * a constant