Evolution and Biodiversity

Evolution and Biodiversity

Evolution • Evolution: change in the gene pool of a population from generation to generation by such processes as mutation, naturalselection,andgeneticdrift.

Biodiversity • The number of different species in an area.

Evolution and the diversity of organisms • When an environment changes, so could the diversity of organisms in that environment. This is because when an organism is adapted to a certain food and environment, any changes in that food or environment could cause genetic variation or diversity of organisms.

Evolution and the diversity of organisms, example: • For example, when a bird eats a type of food, it has a certain beak adapted to breaking or chewing that food. If, for some reason, the bird changes environment causing it to eat a different food, the beak has to adapt over time to eating that food in order for it to survive. Also, if some of the birds in that same species stay where they are they don’t have to adapt to that food, or environment and it causes genetic variation.

Genetic variation: • When animals of the same species have different genes that make them vary from each other.

The theory of evolution • Geology, fossils, and comparative anatomy provides the basis of The Theory Of Evolution because if you look at fossils of past animals you can tell how they evolved over time.

Theory of evolution, example: • For example, a fossil of a mouse is found with very small bones for its mouth. Another fossil of the same species of mice is found from one hundred miles away, but the bones from its mouth are a lot larger. The fossils bones prove geology because since it is 100 miles away, the land could have been different, causing a change in the teeth in the mouth of the mouse. Possibly because of a change in food or environment, and the mouse had to evolve to adapt to those surroundings.

Theory of evolution, example two: • For another example, lets say that a fossil from a different species of mouse is found. The leg bones of the mouse are weak and thin. Another fossil is found, from 100 years later, the bones are thicker and stronger. Since it is from 100 years later, this could have been caused because over time, the mouse could have needed stronger legs, so the species adapted to having thicker, stronger bones.

extinct • No longer in existence; ended or died out.

Mismatch of adaptation: • A mismatch of adaptation is when an organisms traits and adaptations (ex: a polar bear’s thick coat, a duck’s webbed feet) do not match the environment it is in.

Environment • The air, water, minerals, organisms, and all other external factors surrounding and affecting a given organism at any time.

Extinction due to mismatch of adaptation and the environment • A species can become extinct due to mismatch of adaptation and the environment. If an organism’s environment changes and its traits/adaptations are no longer useful to it, the species would either have to adapt to the new surroundings or, if the change is too big, become extinct.

Extinction due to mismatch of adaptation and the environment (2) • Example: If a dense Eucalyptus forest, home to many Koalas, is cut down the Koalas would be forced to find another source of food besides Eucalyptus leaves and another environment to live in or they would become extinct.

Question 1: • Explain: Explain one example of how an organism may become extinct by mismatch of adaptation and the environment.

Question 2: • Relate: If you were a bird and your environment changed, what would happen to your traits and adaptations over time?

Question 3: • Compare: Compare the different mice evolving, and why they needed to evolve.

Question 4 • Explain: Explain one reason why fossils can prove the Theory Of Evolution.

Evolution and Biodiversity