Adaptations How organisms gain an advantage for survival

Adaptations How organisms gain an advantage for survival.

Adaptations § An adaptation is a structure or ability an organism has inherited (genetics) which provides the ability to find food, reproduce or escape predators better than other members of the species.

Adaptations § Organisms are always competing for limited resources. Ex:

Adaptations § Remember most species are in constant danger from predators. § Some individuals are better at avoiding being eating. § Some use camouflage. § Others use speed or flight.

Adaptations

Adaptations § Some individuals are most attractive to the opposite sex than others… § Ex:

Adaptations § Remember there always more offspring sprouting, hatched or born than can possibly survive. § Any small change can make the difference between survival or extinction.

Adaptations § Adaptations occur naturally as a result of genetic variations in any population.

Adaptations § Some genetic variations do not help organisms survive and are neutral. § Ex: Blue eyes or brown eyes. § Most variations are harmful and can cause predation or reproductive failure. § Ex: A white rabbit. § Ex: A peacock without a tail.

Adaptations § The best adapted organisms leave more offspring and past their genes to the next generation thereby changing the nature of the species. § This process helps to explain the amazing variety of life on Earth. § Over time, an adaptation which provides an important advantage can change the frequency of a gene allele (gene choice) in a population, this process is called evolution.

Adaptations § In some symbiotic relationships, organisms can adapt together, this is called coevolution. § �Ex:

Adaptations § Sometimes a successfully organisms have mimic species which imitates the advantage of the original.

Adaptations § The mimic is not choosing to imitate, but is chosen by the same environmental pressure that produced the original. § Ex: Competition for resources. § Ex: Competition to avoid predators. § Ex: Competition for mates.

Adaptations § Adaptations produce organisms that are specialized in a niche of a particular ecosystem. § However, if the environment suddenly changes, the highly adapted organisms may not survive. § Ex: A giant meteor hits, earth cools off, dinosaurs go extinct.

Adaptations § This may explain why the actions of humans which change the environment rapidly, can lead to the lost of so many species. § Ex: Farmers hunt prairie dogs, endangering blackfooted ferrets. § Ex: Humans release FCs into atmosphere, destroying ozone, several amphibian species went extinct.

Succession § A progression of different species take over the community of an area. § It can occur quickly or take several million years. § It can occur naturally or be initiated by human actions. § It usually leads to a climax community dominated by a stable species.

Succession

Succession

Succession

Artificial Selection § Humans can make choices which change species. § By breeding individuals with desired characteristics we “create” breeds. § Ex: 150+ dog varieties, one species. § Ex: Farm animals and crops. § Ex: Samurai crabs

Remember: § Science doesn’t understand all the relationships in ecosystems. § We are far from being able to predict the results of our actions. § You can’t pick a flower without juggling a star.