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Gene flow - also called migration - is any movement of individuals, and/or the genetic material they carry, from one population to another. Gene flow includes lots of different kinds of events, such as pollen being blown to a new destination or people moving to new cities or countries.

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Hybridization and Gene Flow | Learn Science at Scitable

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By continuing to study hybridizing species and hybrid zones, researchers can further understand which sets of genes have permissible gene flow and which are more restricted. Then, by studying genes in the latter category, scientists can learn which genes or gene sets may be important in maintaining species integrity in the face of gene flow.

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Several hundred million years ago, there were no vertebrate animals on land. The only vertebrate species in the world were fish, all of which lived underwater. Competition for food was intense. Some species of fish that lived near the coast developed a strange mutation: the ability to push themselves along in the mud and sand on the shore with their fins. This gave them access to food sources that no other fish could reach. The advantage gave them greater reproductive success, so the mutation was passed along. This is what we call natural selection.

Natural selection is the engine that drives evolution. The organisms best suited to survive in their particular circumstances have a greater chance of passing their traits on to the next generation. But plants and animals interact in very complex ways with other organisms and their environment. These factors work together to produce the amazingly diverse range of life forms present on Earth.

By understanding natural selection, we can learn why some plants produce cyanide, why rabbits produce so many offspring, how animals first emerged from the ocean to live on land, and how some mammals eventually went back again. We can even learn about microscopic life, such as bacteria and viruses, or figure out how humans became humans.

Charles Darwin coined the term "natural selection." You'll typically hear it alongside the often misunderstood evolutionary catchphrase " survival of the fittest." But survival of the fittest isn't necessarily the bloody, tooth-and-claw battle for survival we tend to make it out to be (although sometimes it is). Rather, it is a measure of how efficient a tree is at dispersing seeds; a fish's ability to find a safe spawning ground before laying her eggs; the skill with which a bird retrieves seeds from the deep, fragrant cup of a flower; a bacterium's resistance to antibiotics.

With a little help from Darwin himself, we're going to learn about natural selection and how it created the astonishing complexity and diversity of life on planet Earth.

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Several hundred million years ago, there were no vertebrate animals on land. The only vertebrate species in the world were fish, all of which lived underwater. Competition for food was intense. Some species of fish that lived near the coast developed a strange mutatio­n: the ability to push themselves along in the mud and sand on the shore with their fins.

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Natural Selection - Crash Course Biology #14

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ISB Presentation 22: Natural Selection and Evolutionary Change Flashcards | Quizlet

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Presentation 22: Natural Selection and Evolutionary Change Learn with flashcards, games, and more — for free.

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SC.912.L.15.14 - Discuss mechanisms of evolutionary change other than natural selection such as genetic drift and gene flow.