Population Size Flashcards
What are density dependent factors
Size of population will influence an individual’s probability of survival
5 Examples of density dependent factors
Food, water, disease, habitat, or other limiting factors
What is natality?
Birth rate AKA production of new individuals
What is fecundity?
Physical ability to reproduce
What is fertility?
Measure of actual number of offspring produced (biotic potential)
What is immigration?
Organisms introduced into new ecosystems
Other than immigration, how else can organisms be dispersed?
By wind or water currents over long distances or carried by animals or rafts of drifting vegetation
What is biotic potential?
Max # of offspring a species can produce
What is mortality?
Death rate
What is survivorship?
Percentage of cohort surviving to a certain age
What is life expectancy?
Probable number of yrs of survival for an individual of a given age
Does life expectancy increase?
Yes, as humans age
Do women live longer than men?
Yes
What does emigration do?
Decrease population
What is emigration?
Movement of members out of a population
What do many organisms possess that allow them to facilitate migration into new areas
specific mechanisms
What is population ecology
Study of factors that cause populations to increase or decrease