Chapter 4 and 5 Flashcards
Biodiversity and Evolution Biodiversity, Species Interactions, and Population Control
Change in the genetic makeup of a population of a species in successive generations. If continued long enough, it can lead to the formation of a new species. Note that populations, not individuals, evolve.
biological evolution
Widely accepted scientific theory holding that the number of different species found on an island is determined by the interactions of two factors: the rate at which new species immigrate to the island and the rate at which species become extinct
theory of evolution
Phenomenon in which individuals with adaptive genetic traits produce more living offspring than do individuals without such traits
differential reproduction
Separation of populations of a species into different areas for long periods of time
geographic isolation
Long-term geographic separation of members of a particular sexually reproducing species
reproductive isolation
Species that is found in only one area. Such species are especially vulnerable to extinction
endemic species
Normal extinction of various species as a result of changes in local environmental conditions
background extinction rate
Catastrophic, widespread, often global event in which major groups of species are wiped out over a short time compared with normal extinctions
mass extinction
Number of different species combined with the relative abundance of individuals within each of those species in a given area
species diversity
Total way of life of a species in an ecosystem. It includes all physical, chemical, and biological conditions that a species needs to live and reproduce in an ecosystem.
ecological niche
Species with a broad ecological niche. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions. Examples include flies, cockroaches, mice, rats, and humans.
generalist species
Species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food.
specialist species
Species that normally live and thrive in a particular ecosystem
native species
Species that migrate into an ecosystem or are deliberately or accidentally introduced into an ecosystem by humans.
nonnative species
Species that play roles affecting many other organisms in an ecosystem
keystone species
Species that plays a major role in shaping a community by creating and enhancing a habitat that benefits other species
foundation species
variety of different species, genetic variability among individuals within each species, variety of ecosystems, and functions such as energy flow and matter cycling needed for the survival of species and biological communities
biological diversity
Types of diversity
Biological, species, genetic, ecological, and functional
estimated amount of organisms on Earth
8-100 million, best guess: 10-14 million, identified: 1.9 million
how to differentiate between biomes
distinct climates and certain species that have adapted to them
five species interactions
interspecific competition, predation, parasitism, mutualism, and commensalism
limiting factors (some examples)
precipitation, soil nutrients, light, water, space, and temperature
range of chemical and physical conditions that must be maintained for populations of a particular species to stay alive and grow, develop, and function normally
range of tolerance
the maximum population of a given species that a particular habitat can sustain indefinitely
carrying capacity
the number of individuals in a population found in a particular area or volume
population density
exceed the carrying capacity of the environment. Population crash, a sharp decline in population
overshoot and dieback
a population’s distribution of individuals among various age groups
age structure
