Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Population Ecology
Ch.53
| Question | Answer |
|---|---|
| population ecology | the study of populations in relation to their environment |
| population ecology explores | biotic and abiotic factors influence the abundance, dispersion, and age structure of populations |
| population | a group of individuals of a single species living in the same general area |
| How are populations described? | boundaries and size |
| size | the number of individuals living within those boundaries |
| density | population is the number of individuals per unit area or volume |
| Dispersion | the pattern of spacing among individuals within the boundaries of the population |
| mark-recapture method | estimate size of wildlife populations |
| immigration | the influx of new individuals from other areas |
| emigration | the movement of individuals out of a population and into other locations |
| Dispersion patterns | - clumped - uniform - random |
| clumped | individuals are aggregated in patches |
| uniform | pattern of dispersion may result from direct interactions between individuals in the population |
| random | position of each individual in a population is independent of other individuals |
| demography | study of vital statistics of population and how they change over time |
| demographics | - birth - death - migration |
| life table | summarizes the survival and reproduction rates of individuals in specific age-groups within a population |
| To construct a life table, researchers often follow the fate of a ____. | cohort |
| cohort | a group of individuals of the same age, from birth until all of the individuals are dead |
| survivorship curve | a plot of the proportion or numbers in a cohort still alive at each age |
| survivorship curve types | 1. type 1 2. typ 2 3. type 3 |
| type 1 | flat at the start, reflecting low death rates during early and middle life, and then drops steeply as death rates increase among older age-groups |
| type 3 | drops sharply at the start, reflecting very high death rates for the young, but flattens out as death rates decline for those few individuals that survive the early period of die-off. |
| type 2 | intermediate, with a constant death rate over the organism's life span |
| Two key factors populations not experiencing large amounts of immigration or emigration | 1. survivorship 2. how population size changes over time |
| intrinistic rate of increase | the per capita rate at which an exponentially growing population increases in size at each instant in time |
| carrying capacity | symbolized by K, as the maximum population size that a particular environment can sustain |
| logistic population growth | the per capita rate of population growth approaches zero as the population size nears the carrying capacity (K) |
| Life history | evolutionary outcomes reflected in its development, physiology, and behavior |
| semelparity | "one shot" pattern of big bang reproduction |
| iteroparity | repeated reproduction |
| density independent | a birth rate or death rate that does not change with population density |
| density dependent | a death rate that increases with population density or a birth rate that falls with rising density |
| population dynamics | influenced by many factors and in turn affect other species |
| Density- Dependent Regulation Mechanisms | - competition for resources - disease - predation - territoriality - intrinistic factors - toxic wastes |
| Competition for Resources | Increasing population density intensifies competition for nutrients and other resources, reducing reproductive rates. |
| Disease | If the transmission rate of a disease increases as a population becomes more crowded, then the disease's impact is density dependent |
| Predation | an important cause of density- dependent mortality if a predator captures more food as the population density of the prey increases |
| Territoriality | can limit population density when space becomes the resource for which individuals compete |
| Intrinistic factors | can regulate population size |
| Toxic wastes | yeasts and ethanol |
| metapopulation | immigration and emigration are important when a number of local populations are linked |
| demographic transition | the movement from high birth and death rates toward low birth and death rates, which tends to accompany industrialization and improved living conditions |
| ecological footprint | summarizes the aggregate land and water area required by each person, city, or nation to produce all the resources it consumes and to absorb all the waste it generates |
Created by:
savepeople
Popular Biology sets