What is the difference between natural breeding and selective breeding?

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Natural breeding refers to the random mating that occurs between two individuals of the same species. 

Conversely, selective breeding has been performed for centuries by humans hoping to produce offspring with desirable traits. Farmers have selectively bred their livestock in the hopes of producing healthier, larger specimens. For example, they might hope to produce a cow that gives a lot of milk or a horse that runs well.

Modern breeds of dogs came into existence by careful selection and breeding. All modern dogs can be traced to a wolf-like ancestor. Selections were made for traits like hunting ability, fighting ability, being a tame companion, and appearance. 

Many crops that nourish the planet are the results of selectively breeding plants with traits like resistance to insects or an ability to grow in a drier climate. Larger varieties of fruit have been selected for to provide more food for people. These crops are different than their "wild" cousins that grow in nature.

In selective breeding, there is no guarantee the desired traits will be inherited by the offspring. Due to the processes of crossing over and independent assortment (which occurs during meiosis), unique gametes are produced. These gametes may not have the characteristics desired by the person performing the selective breeding. 

I have included a link with details of various types of artificial selection (selective breeding) performed by people to try to "improve" the resulting offspring.

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Compare and contrast selective breeding and natural selection?

Pri1003 is entirely correct.

One of the points that bears emphasis here is the fact that "selective breeding" is entirely unique to, and confined, to humans, and is responsible for everything from modern agriculture to the range of size in domesticated dogs.

The process itself, and its results, can be viewed in the link I've attached to a Youtube video on the Russian efforts to domesticate foxes.

In general, I prefer to call selective breeding "artificial breeding" because it clearly establishes that this is not a process driven by nature, but by humans. We might think that animals which breed based on cosmetics, such as bright plumage or staged combat, are participating in selective breeding, but this is referred to specifically as sexual selection. There is some debate over whether humans have become a sexually selective species in modern times. In contrast to artificial selection, however, sexual selection is still considered an aspect of natural selection.

We must also be careful never to assume that the "direction" that humans build into their artificial breeding, such as seeking high-productivity crops or docile animals, is present within natural selection.

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