Adaptation leads to Evolution Ryan Kiddey

The Evolution Basics… What is a species? Species: a group of organisms that share very similar traits and can reproduce only within that group. Traits are inherited from one generation to the next. What is evolution? Evolution: Changes in inherited traits over time. What causes evolution? Natural genetic variations (mutations) in the genes (DNA) cause evolution to occur over time.

Evolution? Who’s big idea was it? Charles Darwin (1809-1882) An English guy In 1831, he sailed to the Galapagos Islands on the HMS Beagle as a naturalist. Made very important observations while on the islands. Darwin coined the term: Natural Selection

Darwin’s Finches…

Natural Selection… What is natural selection? Natural Selection: organisms with traits best suited to their environment are more likely to survive… Why??? REPRODUCE!!!!!!!!!!!! THUS passing on their best suited traits… most adaptable to the environment. Mantis Video

The Principles of Natural Selection Organisms produce more offspring than can survive. Natural differences, or variations, occur among individuals of a species. Some variations are passed to offspring. Some variations are helpful to the specie within its habitat. Over time, the offspring of individuals with helpful variations make up more of the population. Eventually will become a separate species.

Variation and Adaptation Natural Selection accounted for differences among species of finches AKA – Variation Variation: inherited trait that makes an individual slightly different from other members of its species. Caused by natural mutations in the genes/DNA of the organism. What differences among us are caused by variation? A good variation for some humans? FIV in Cats and HIV in Humans

Variation and Adaptation Some variations are more helpful than others. Variation can lead to adaptation Adaptation: any variation that makes an organism better suited to its environment. What variations might a polar bear require in order to adapt to a warming world in order to survive?

Speed of Evolution The speed of evolution depends on the species environmental conditions. Gradualism: a model that describes evolution as a slow, ongoing process by which one species changes to a new species --- tens of millions of years Punctuated Equilibrium: Model of rapid evolution which is caused by the mutation of a few genes and results in a new species over a relatively short period of time --- hundred thousand years or a million years. gradualism vs. punctuated equilibrium (VIDEO)

Salamander Questions: 1. What was the ecological cause of the salamanders evolution? 2. How do scientists know that the two species are different at the other end of the valley? 3. What things in their environment may have caused these animals to adapt to become a new species?

Animals Adapt… How? Ring Species Question 1: The valley that separated the two… Why is this important? Question 2: They are different species because they can no longer interbreed because their DNA is so different. Question 3: What do you think…?

Why is adaptation and evolution important? The Theory of Evolution is crucial to biological sciences. Is a major reason for the recent rapid advancement in medicine and biological sciences. Human health… Any ideas why?

Evolution and Human Health? New TB