Unit 2 Biodiversity

Variety and variability of life on earth

Total number of species in the area

Total variety of genes within a species

Species that occur nowhere else in the world

Total number of ecosystems in the area

Ecosystems that occur nowhere else in the world

habitat loss, invasive species, over , exploitation, climate change along with global warming, pollution

Changes in DNA that lead to changes in a species. Mutations are the cause for genetic diversity

Used to Quantify Biodiversity. It is the total number of species in an area

The Species Evenness is another method to measure biodiversity. Evenness expresses how uniformly the individuals in a community are distributed among the different species

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.

Occurs when the size of a population is reduced at least for one generation.

Services provided by our ecosytem. It is of four types, supporting, regulating, provisioning and Cultural

Something produced by the ecosytem that can be directly used by humans. Eg, Fruits, Vegetables

processes that help environmental conditions stable. Eg, Flood prevention, Climate regulation

Cultural, emotional, or aesthetic benefits provided. Educational, recreational, aesthetic

Processes that are needed for human survival that are extremely costly. E.g, Nutrient cycling, primary productivity

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.

a change or process by which an organism becomes better suited to its environment.

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.

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 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 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.

Succession where there was no previous biotic community. Ex: Newly formed island