Unit 2 Biodiversity Flashcards
Biodiversity
Variety and variability of life on earth
Species Richness
Total number of species in the area
Genetic Diversity
Total variety of genes within a species
Endemic species
Species that occur nowhere else in the world
Ecosystem Diversity
Total number of ecosystems in the area
Unique ecosystems
Ecosystems that occur nowhere else in the world
Causes for loss of Biodiversity
habitat loss, invasive species, over , exploitation, climate change along with global warming, pollution
Mutations
Changes in DNA that lead to changes in a species. Mutations are the cause for genetic diversity
Species Richness index
Used to Quantify Biodiversity. It is the total number of species in an area
Species evenness
The Species Evenness is another method to measure biodiversity. Evenness expresses how uniformly the individuals in a community are distributed among the different species
Simpsons Index
Used to quantify Biodiversity . D = Sigma n/N where n is the total number of individuals of a particular species and N is the total number of organism in all the species. Low Simpsons index number means more biodiversity and vice versa.
Population Bottle neck
Occurs when the size of a population is reduced at least for one generation.
Ecosystem services
Services provided by our ecosytem. It is of four types, supporting, regulating, provisioning and Cultural
Provisioning services
Something produced by the ecosytem that can be directly used by humans. Eg, Fruits, Vegetables
Regulating services
processes that help environmental conditions stable. Eg, Flood prevention, Climate regulation
Cultural Services
Cultural, emotional, or aesthetic benefits provided.
Educational, recreational, aesthetic
Supporting services
Processes that are needed for human survival that are extremely costly.
E.g, Nutrient cycling, primary productivity
Island Biogeography Theory
This model states that the number of species (richness) 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 locally on the island. Two features of an island determine the immigration and extinction rates: island size and an island’s distance from the mainland.
Adaptations
a change or process by which an organism becomes better suited to its environment.
Structural adaptations
These adaptations are body structures that allow an animal to find and consume food, defend itself, and to reproduce its species. Structural adaptations include things such as body color, body covering, beak type, claw type.
Behavioural adaptations
These are adaptations that help an organism meet their needs for food, water, shelter, and protection.For example, bird calls and migration are behavioral adaptations.
Physiological adaptations
Physiological adaptation is an internal body process to regulate and maintain homeostasis for an organism to survive in the environment in which it exists, examples include temperature regulation, release of toxins or poisons, releasing antifreeze proteins to avoid freezing in cold environments .
Succession
Succession is the gradual and fairly predictable change in species composition of an area over time.
During succession, some species colonize and their populations become more numerous, whereas other species populations decline and even disappear.
Primary Succession
Succession where there was no previous biotic community.
Ex: Newly formed island
Secondary succession
Succession in a previously occupied by a community
Ex: Mount St. Helen’s blast area
Aquatic succession
transition from pond or lake to terrestrial community
Pioneer species
The organism that first colonize a deserted area during succession
Climax community
The final diverse ecosystem formed during the end of succession
