The variety of life across all levels of ecological organization
the number or variety of species in a particular region
the differences in DNA among individuals within species and populations
the number and variety of ecosystems
the study of how organisms interact with each other and their environment
a group of individuals that interbreed and produce fertile offspring
members of a species that live in the same area at the same time
All the populations in a particular area
All the living things an their physical environments within a particular area
Part of an ecosystem that is living or used to be living. Ex. squirrel, a dead leaf, a cicada bug, bacteria, rotting tree stump, etc...
Part of an ecosystem that has never been living. Ex. rocks, air temperature, water, oxygen, light, wind, pH, etc...
The specific environment in which an organism lives
Anything an organism needs. Ex. water, food, living space, etc...
A stable ecosystem is both ____________and _____________.
resistant (can fend off harmful factors) and resilient (can bounce back after harsh natural disasters)
Which group of animals has the greatest known species diversity?
Which type of habitat would have greater species diversity- a small forest or a large field of corn?
A small forest would have greater species diversity than a cornfield because species diversity tends to increase with diversity of habitats. A field consisting of just corn is a fairly uniform habitat and cannot support as much life. A forest, on the other hand, consists of more plant types and ecological niches, and thus could support a larger variety of species.
Describe examples of ecosystems services.
Provides us with food, clean air/water, medicine, and other resources. Provides a cultural, spiritual, and recreational facets to life. Supports decomposition of wastes (nutrient cycling). Can regulate global climate change and controls pests/diseases.
The disappearance of a particular population from a given area, but not of the entire species globally.
a species that has a high risk of extinction
a species that is likely to become endangered soon throughout all or part of its range.
the process by which the land that is suitable for wildlife becomes separated into smaller patches that are not connected.
the illegal killing or capturing of an organism
Is extinction a natural process?
YES. Extinction is a natural process. Organisms have been going extinct for all of Earth's history.
Compare and contrast extinction and extirpation.
Extinction occurs when the last member of a species dies. Extirpation, on the other hand, occurs when a particular species disappears from a given area only, not globally.
Describe habitat alteration.
Habitat destruction or change can limit the number of species a habitat will support. This is the greatest cause of biodiversity loss!
Species may become endangered or even extinct if they are trapped, hunted, or otherwise harvested faster than the species can reproduce and grow.
invasive species reproduce and spread rapidly, displacing native species.
What are the reasons for biodiversity loss in an area?
Habitat alteration (habitat change and fragmentation)
Which type of species is more likely to become extinct, an endangered species or a threatened species?
An endangered species because it is at high risk of becoming extinct while a threatened species is at high risk of becoming endangered.
How do the effects of climate change differ from the effects of habitat alteration, invasive species, overharvesting, and pollution?
Climate change affects all of Earth, while the others listed have more local effects, only affecting the part of Earth where they are occurring.
What human activities lead to habitat loss?
forest clearing and road building for land use and development
What are habitat islands and how do they occur?
They are patches of suitable habitat type surrounded by large areas of unsuitable habitat. When humans clear an area for development, they remove, alter, or destroy the resources organisms need to survive.
What factors determine whether nonnative species are considered invasive?
If nonnative species populations increase rapidly and they spread and displace native species, they are considered invasive.
List two nonnative species-- one that is invasive, and the other that is not invasive.