Selective Breeding: The Two Types Of Artificial Selection

It can improve farm animals. For instance breeding two cows of different species enhances the milk and meat quality and quantity. The milk has less milk fat which is better for buyers who don’t have to remove as much milk fat. This makes a bigger profit for the farmer. The meat is leaner with less fat which both consumers and buyers like. This makes the meat more valuable. Many farmers who crossbreed say “By doing crossbreeding, you’re getting the best of both breeds.” Another farm animal that has been genetically changed is the goat. Scientist at the University of Utah mixed a goat with a spider to create a spider goat. The logic behind this is that the milk has silk in it when the goat is milked. According to Randy Lewis who created freckles the spider goat the milk gets processed in a lab. In an interview with him he stated “We milk Freckles together and process it in the lab to leave only the silk proteins. With a glass rod, we delicately lift out a single fibre of what is very obviously spider silk and spool it onto a reel.” However it isn’t necessary for our survival or the animals which is when spider goats should not be a crossbred animal. It has to be stopped in instances like this. It is perfectly fine to crossbreed when the animal and humans both benefit. If only humans benefit and the animal suffers it is cruel to the

Genetic diversity allows the population to adapt to changing environments and it contributes and adds to the gene pool.

Artificial selection – a breeder that selects desired traits for a species and then breeds that species to have those traits.

The study or practice of attempting to ‘improve’ the human gene pool by encouraging the reproduction of people considered to have desirable traits and discouraging or preventing the reproduction of people considered to have undesirable traits; Eugenics.

Genetic diversity provides a species with its form and function. A species genotype refers to their genetic code; what their cells are going to be used for – hair cell, eye cell, muscle cell, etc. A species phonotype refers to the way in which that species gene will be expressed – blonde hair, blue eyes, large muscle tone; which significantly impacts the success of that individuals genes. Without genetic diversity among populations the gene pools would be very limited, which gives way to a rise in mutations and inevitably the end of a species. “Genes regulate body size, shape,

After Charles Darwin published his book “On the origins of species” in 1859, evolution became a hot topic of discussion; the notion of the human race improving itself by selective breeding started to spread (Winfield, 2012). For years

Selective breeding also could cause a decrease in biodiversity due to inbreeding. Inbreeding is the production of breeding between closely related individuals [2] and is used as it increases the chance of having favourable alleles and desirable phenotypes in the offspring. However, due to the individuals close genetic relations to one another this can cause many problems for the biodiversity of the population of dairy cows. Traits that may be disadvantageous now will be continuously chosen against during genomic selection and embryo transfer as the DNA is being scanned and checked for undesirable traits. However, this disadvantageous trait may become an advantageous trait in the future but it will be lost through the generations of selective breeding against it and are difficult to get back. As a result, this affects the evolution of the species as a whole because they develop and change to suit the desirable traits chosen which results in the undesirable traits being lost altogether.

In 1970, selective pure breeding was introduced and this improved the mass breeding of cattle, sheep and horses. This also enabled higher prices and profits for meat and wool.

Inbreeding is the outcome of offspring from mating of individuals that are related by a descent. It is important to limit this effect in conservation programs due to the increased amount of homozygosity and exposed deleterious recessive alleles, which increase the risk of extinction to the population.

Offspring that possess favorable traits are more capable of surviving into adulthood and thus reproducing. We know from genetics that there is an increased likelihood that their offspring would also possess that desirable trait. The population of individuals possessing the trait would increase as more individuals possessing the trait survived to reproductive years, and fewer without the trait did not. Natural selection can help prevent a species from going extinct if they were to face adverse conditions that

A species’ long-term reproductive success is the most important factor when determining whether that species cooperatively breeds. Cooperative breeding is when an individual forgoes reproducing to assist offspring that are not their own (Hoogland 1983). Although there is an absence of direct fitness, individuals still gain genetics benefits through kin selection (Queller & Strassmann 1998). Kin selection allows some of the individual’s genes to pass on to the next generation by helping his or her relatives, who carry similar genes, to raise their young (Queller & Strassmann 1998). Individuals that help their kin raise their young, also known as helpers, perform tasks, like feed, groom, and watch the young. They also protect the territorial boundaries and alert other individuals of incoming threats (Jennions and MacDonald 1994). The best way to analyze the effectiveness of cooperative breeding is through a species’

For artificial selection, humans usually enhance or repress the genetic traits of organisms through some ways like selective breeding. While for natural selection, nature will allow the advantages for those

There is another side to the biodiversity of the evolutionary field, as the population weakens the species start the inbreeding of smaller populations, thus playing a role in the extinction of a species. Inbreeding is reproduction among members of a species that are genetically similar. The genetic inbreeding is designed to bolster populations of species whose numbers are in decline. However, when only a few species or varieties of a species are cultivated or survive, the genetic diversity of the organism declines, and population is more vulnerable to being wiped out by new diseases or climate changes because of the inbreeding (Alters, 2000).

If these traits that it possesses that made it different were useful than that creature may reproduce more than normal. Of course in Darwin’s day DNA had not been discovered but it was known that traits were passed to offspring. Natural selection is when the organisms with good traits survive the trials of nature. Artificial selection is what breeders do, the cow that gives more milk, or the plant that produces larger fruit are selected to be reproduced. Encyclopedia Encarta defines natural selection as “the process by which environmental effects lead to varying degrees of reproductive success among individuals of a population of organisms with different hereditary characters, or traits. The characters that inhibit reproductive success decrease in frequency from generation to generation. The resulting increase in the proportion of reproductively successful individuals usually enhances the adaptation of the population to its environment”

Generally speaking, there are numerous issues related to genetic diversity which include mutations, sexual reproduction, migration, and population size.