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fixed action patterns
genetically based behaviors, seen across a species, that can be set off by a specific stimulus
the process by which certain animals form attachments during a critical period very early in life
the paired presentation of two different types of stimuli causes an animal to form an association between them
refers to the adaptive changes in males and females that lead to an increased ability to secure a mate
a higher ranking animal has a greater access to resources than a lower ranking animal
a behavior that has the potential to decrease the lifetime reproductive success of the altruist, while benefiting the reproductive success of another member of the society
adaptation to the environment due to the reproductive success of the individual's relatives
includes the personal reproductive success of the individual and the reproductive success of relatives
making a minimal, short-term reproductive sacrifice in order to maximize future reproductive potential
the study of interactions between organisms with each other and with the physical environment
the highest possible rate of natural increase for a population when resources are unlimited
age structure diagrams
diagrams for hypothetical populations that are increasing, stable or decreasing
the number of individuals added each generation increases as the total number of females increases
Selection for life history traits that are sensitive to population density; also called density-dependent selection.
the members of different species try to use a resource that is in limited supply
decreased competition between the two species leading to increased niche specialization
characteristics to be more divergent when populations belong to the same community rather than when they are isolated
a symbiotic relationship between two species in which one species is benefited and the other neither benefited nor harmed
a change involving a series of species replacements in a community following a disturbance
persistance through time, resistance to change, recovery once a disturbance has occurred
organisms that play a greater role in maintaining the function and diversity of an ecosystem
highest-latitude Northern Hemisphere biome, where low, cold-tolerant plants survive with only a brief growing season
biome just south of the tundra; characterized by a northern coniferous forest composed of pine, fir, hemlock, and spruce tree and acidic, mineral-poor topsoils
temperate deciduous forests
biome, occupy regions that have warm summers, cold winters, and moderate precipitation, shed leaves in winter,
tropical rain forests
Characterized by the greatest diversity of species, believed to include many undiscovered species. Occur near the equator. Soils tend to be low in nutrients. Distinct seasonality: winter is absent, and only two seasons are present (rainy and dry).
plants such as mosses, lichens, and orchids, that grow on other plants but do not take nutrients from them
areas of land that tend to occur along coasts and have dry winters and receive most of rain during the winter
a region of grassland with scattered trees lying between the equatorial forest and the hot deserts in either hemisphere
wetlands without trees; in North America, this type of land is characterized by cattails and rushes
when the surface water cools and the deeper water is closer to surface temperature, so deep-water organisms move up
water temp increases, density barrier disappears, water, oxygen and nutrients free to circulate
the rising of cold water from deeper layers to replace warmer surface water that has been moved away
a reversal of airflow between normally low atmospheric pressure over the western Pacific; the cause of El Nino
spots on the ocean floor where hot gases and minerals escape from earth's interior into the water
biology that studies all aspects of biodiversity with the goal of conserving natural resources
a species whose impact on its community or ecosystem are much larger and more influential than would be expected from mere abundance
reduces the amount of habitat typical of an ecosystem because the edges around a patch have a slightly smaller habitat
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