Unit 3 Vocab Flashcards
Population
Individuals of a species in a given area at a given time
Community
All populations within a given area
Density-dependent factor
Factor that influences an individual’s probability of survival and reproduction in a way that depends on the size of the population
Carrying Capacity
Limit of how many individuals in a population the environment can sustain
Exponential Growth
Growth model that estimates a population’s size over a period of time, not including limiting factors
Logistic Growth
Growth model that estimates a population’s size over a period of time that flattens out after a while because of limiting factors
Overshoot
When a population becomes larger than the environment’s carrying capacity
K-selected species
Low intrinsic growth rate, population increases slowly until CC is reached
- large organisms
- late reproductive maturity
- few offspring at once
R-selected species
High intrinsic growth rate, population increases rapidly, often leads to overshoots and die-offs
- smaller organisms
- early reproductive maturity
- many offspring
Keystone species
Species that plays an important part in the community, more than its relative abundance might suggest
Ecological Succession
The predictable replacement of one group of species by another over time
- primary: on surfaces initially devoid of soil
- secondary: some soil left over
CBR/DBR
Crude Birth/Death Rate
-# of births/deaths per 1000 per year
TFR
Total Fertility Rate
-estimate of the average number of children each woman has throughout her life
Pop. Pyramid
Age structure diagram that is widest at the bottom and smallest at the top , typical of developing countries
Demographic transition
As a country goes from different types of economies, it undergoes a predictable population change
