Unit 2 Flashcards
What are the 3 levels of biodiversity?
Genetic diversity, species diversity, and ecosystem diversity
What are the two methods to quantify biodiversity?
Species richness and species evenness.
What is extinction?
Extinction is the complete disappearance of a species from Earth.
What is mass extinction?
A mass extinction is a period of time in which a significant portion of Earth’s species go extinct within a relatively short period.
What is the common cause for all of the 5 mass extinction
Catastrophic events, such as asteroid impacts or massive volcanic eruptions, are commonly cited as the cause of mass extinctions. These events trigger widespread environmental changes that many species cannot survive.
What are the ecosystem services?
Ecosystem services are the myriad of benefits that humans derive from ecosystems.
What are examples of each ecosystem services?
Provisioning , Regulating , Supporting , and Cultural services
Provisioning services
Food, fresh water, fuelwood, fiber, genetic resources
Regulating services
Climate regulation, water purification, disease control, pollination
Supporting services
Nutrient cycling, soil formation, primary production.
Cultural services
Recreation, aesthetic value, spiritual enrichment, educational opportunities. The theory of island biogeography
What is the theory of the Island biogeography?
The theory of island biogeography proposes that the number of species on an island is determined by a balance between immigration rates and extinction rates. These rates are influenced by factors such as island size and distance from the mainland.
What is the difference between a niche generalist and a niche specialist?
A niche generalist can utilize a wide range of resources and tolerate a broad range of environmental conditions. A niche specialist has a narrow range of resources and environmental tolerances
Why would an organism evolve to be a specialist?
Organisms may evolve to become specialists when resources are limited or when environmental conditions are stable and predictable. Specialization allows for efficient exploitation of a specific resource or habitat.
What is the range of tolerance?
Range of tolerance refers to the range of environmental conditions (e.g., temperature, salinity, pH) within which a species can survive and reproduce.
What are the key principles of evolution by natural selection?
The key principles of evolution by natural selection are: variation within a population, inheritance of traits, overproduction of offspring, and differential survival and reproduction (natural selection).
What is “selective pressure” as it pertains to evolution by natural selection?
Selective pressure refers to any environmental factor that influences the survival and reproduction of individuals within a population. These pressures can be biotic (e.g., predation, competition) or abiotic (e.g., temperature, drought).
What is ecological succession?
Ecological succession is the gradual change in species composition of a community over time.
What are the two types of ecological succession?
The two types are primary and secondary succession.
What is the key difference between the two types of ecological succession?
The key difference is that primary succession begins in an area lacking soil, while secondary succession occurs in an area where soil is already present.
What are some examples of anthropogenic disturbance succession to occur?
Anthropogenic disturbances leading to primary succession include volcanic eruptions creating new land, strip mining removing all soil and vegetation, and glacier retreat exposing bare rock. Anthropogenic disturbances leading to secondary succession include forest fires, logging, and agricultural abandonment.
What is an indicator species?
An indicator species is a species whose presence, absence, or abundance reflects the overall health of an ecosystem.
What is a keystone species?
A keystone species is a species that has a disproportionately large impact on its ecosystem relative to its abundance. Its removal can cause significant changes in the ecosystem’s structure and function.
What is an Independent variable?
Independent variable: The variable that is manipulated or changed by the researcher.
What is an Dependent variable?
Dependent variable: The variable that is measured or observed.
What is a constant variable?
Constant Variable: A constant variable (or controlled variable) is a factor that remains unchanged throughout the experiment.
What is a control group?
The control group is a group in the experiment that does not receive the experimental treatment or manipulation.
What is a testable hypothesis?
A testable hypothesis is a clear, specific statement predicting the outcome of an experiment, which can be tested through experimentation and observation.
