| A | B |
|---|
| Interspecific Competition | Two or more different species compete |
| Predation | One species feeds directly on another species |
| Parasitism | One organism feeds on another, harming the other (host) |
| Mutualism | Two species interact and both benefit by the interaction |
| Commensalism | Two species interact and one benefits and the other is not harmed or helped |
| Herbivores as predators | walk, swim or fly to the prey |
| Carnivores as predators | Pursue or ambush the prey |
| Camouflage | Used by predators and prey to hide |
| Coevolution | Changes in gene pool of one organism can lead to changes in another |
| Examples of parasites | tapeworms, mistletoe, sea lampreys |
| Examples of mutualism | Oxpecker and black rhinos, clownfish and sea anenome |
| Example of commensalism | epiphytes and large tropical trees |
| Resource partitioning | Several species sharing resources in different ways |
| Population dynamics | Study of population change in response to environment |
| Clumping | type of dispersion where organisms live in close groups |
| Uniform | type of dispersion where organisms live in evenly spaced arrangement |
| Random | type of dispersion where organisms live in randomly spaced arrangement |
| Age structure | proportions of a population at different ages |
| Biotic potential | capacity for population growth under ideal conditions |
| Intrinsic rate of increase (r) | growth of a population if there was unlimited resources |
| Environmental resistence | All the factors that limit the growth of a population |
| Carrying capacity | maximum sustained population of an environment without being degraded |
| Logistic growth | Rapid exponential growth followed by a leveling off |
| Exponential growth | equals the J curve |
| S curve | equals logistic growth |
| r-selected species | capacity for a high rate of population increase |
| K-selected species | species that do not have a high rate of population increase |
| mosquito, rodent, frog | Examples of r-selected species |
| elephants, whales, humans | Examples of K-selected species |
| Population density | number of individuals of a population in a particular area or volume |
| Density dependent factors | population factors created by the population itself (food shortage, etc) |
| Density independent | Population factors not reliant on the size of the population (weather, etc) |
| Boom-and-bust | Population increase followed by a dieback |
| Four patterns of variation of population size | stable, irruptive, cyclic, irregular |
| Ecological succession | Gradual change in species composition over long periods of time |
| Primary succession | establishments of communities where there was no soil at the start |
| Secondary succession | establishments of communities where there was soil at the start |
| Glacier retreat, volcanic eruption | Where primary succession can occur |
| forest fire, farm abandonment | Where secondary succession can occur |
| Pioneer species | first species in primary succession (lichen) |
| Climax community | Final community of any succession |
| Population change | (birth + immigration) - (death + emigration) |
| Fertility rate | number of children born to a woman during her lifetime |
| replacement-level fertility rate | average number of children that couples in a population must bear to replace themselves |
| Baby boom | time after WWII when many children were born in the U.S. |
| Factors affecting birth rates | labor force shortage, pensions, raising and educating, employment for women |
| infant mortality rate | number of children per 1,000 live births who die before 1 year. |
| Life expectancy | average number of years a newborn infant can expect to live |
| Expanding rapidly | population with many pre-reproductive and reproductive people |
| Expanding slowly | slowly growing populations |
| Stable | populations with equal numbers of prereproductive and reproductive ages |
| Declining | population with less prereproductive ages than reproductive |
| Demographic transition | Four distinct stages concerning industrialization of a society |
