How Artificial Selection Works With Animals

Labradoodle
The "Labradoodle" is a product of artificial selection.

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Artificial selection involves mating two individuals within a species that have the traits desired for the offspring. Unlike natural selection, artificial selection isn't random and is controlled by the desires of humans. Animals, both domesticated and wild animals now in captivity, are often subjected to artificial selection by humans to get the ideal animal in looks, demeanor, or other desired characteristics.

Darwin and Artificial Selection

Artificial selection isn't a new practice. Charles Darwin, the father of evolution, used artificial selection to help bolster his work as he came up with the idea of natural selection and the Theory of Evolution. After traveling on the HMS Beagle to South America and, perhaps most notably, the Galapagos Islands, where he observed finches with differently shaped beaks, Darwin wanted to see if he could reproduce this type of change in captivity.

Upon his return to England, Darwin bred birds. Through artificial selection over several generations, Darwin was able to create offspring with desired traits by mating parents that possessed those traits. Artificial selection in birds could include color, beak shape and length, size, and more.

Benefits of Artificial Selection

Artificial selection in animals can be a profitable endeavor. For instance, many owners and trainers will pay top dollar for racehorses with particular pedigrees. Champion racehorses, after they retire, are often used to breed the next generation of winners. Musculature, size, and even bone structure can be passed down from parent to offspring. If two parents can be found with the desired racehorse characteristics, there's an even greater chance that the offspring will also have the championship traits that owners and trainers desire.

A common example of artificial selection in animals is dog breeding. As with racehorses, particular traits are desirable in different breeds of dogs that compete in dog shows. The judges look at coat coloring and patterns, behavior, and even teeth. While behaviors can be trained, there is also evidence that some behavioral traits are passed down genetically.

Even among dogs not entered in shows, certain breeds have become more popular. Newer hybrids such as the Labradoodle, a mix between a Labrador retriever and a poodle, and the puggle, which comes from breeding a pug and a beagle, are in high demand. Most people who like these hybrids enjoy the uniqueness and the look of the new breeds. Breeders choose the parents based on traits they feel will be favorable in the offspring.

Artificial Selection in Research

Artificial selection in animals also can be used for research. Many labs use rodents such as mice and rats to perform tests that aren't ready for human trials. Sometimes the research involves breeding mice to get the trait or gene to be studied in the offspring. Conversely, some labs research the lack of certain genes. In that case, mice without those genes are bred to produce offspring lacking that gene so they can be studied.

Any domesticated animal or animal in captivity can undergo artificial selection. From cats to pandas to tropical fish, artificial selection in animals can mean the continuation of an endangered species, a new type of companion animal, or a lovely new animal to look at. While these traits may never come about through natural selection, they are achievable through breeding programs. As long as humans have preferences, there will be an artificial selection in animals to make sure those preferences are met.