Inbreeding

 Advantages of inbreeding include the prevention of genetic recombination, which would be beneficial given the genomes of both parents were absent of all possible deleterious alleles. Additionally, specific traits can be selected for via inbreeding, and these traits would be fixed quickly. This is the case in selecting specific traits of dogs. If the phenotype of a heterozygous genotype were not beneficial for the organism and either homozygous allele were preferable, inbreeding would be advantageous because it causes the creation of more homozygotes in a population. If you think about it, two individuals who have the same alleles, if they combine their genetic information, these two similar alleles, then their offspring will be homozygous for this allele. This is what causes the drastic amount of homozygosity in the population. If enough individuals in the population interbred until the point that only homozygous individuals existed and their genomes were purged of deleterious alleles, it would then be okay for the individuals to stop inbreeding. Even if their was genetic recombination, it would be unlikely that the recombination included deleterious alleles, or even different alleles. I guess it would still technically still be inbreeding, but it could be with more distantly related relatives. 


There are usually more disadvantages to inbreeding that advantages. As I said above, inbreeding increases homozygosity. This widespread increase in homozygosity means there is less allelic vacation in the population. This makes the population more susceptible to genetic diseases, especially rare diseases caused by deleterious recessive alleles. With less genetic variation, the organisms, no probably the entire population, will be less able to adapt to new and changing environments. There would be no diversity or new traits for nature to select for allow to continue to survive. If the heterozygosity were more beneficial for the organism, they would lose this benefit due to inbreeding.

Comments

Post a Comment

Popular posts from this blog

Cloning - Part 1

Image
          Baby Elizabeth Ann, the cloned black footed ferret           Recently, I have read a couple stories of animal cloning in the name of genetic diversity. I think these are interesting topics and relevant to the class. In August of 2020, a critically endangered animal called Przewalski’s horse was cloned from the DNA that had been collected in 1980 and preserved in the San Diego Zoo Global. With conservation efforts, the species was brought back from the brink of extinction and re-introduced to its native grasslands in China and Mongolia. What I think a key point to consider is that almost all of the the horses can be traced back to only 12 predecessors. Conservationists were only able to work with the genetic diversity of 12 horses - that is how critically endangered they were. The new baby that has been cloned using old DNA is meant to contribute genetic diversity into the dwindling species.  In December of 2020...
Read more

What is Evolution? Fact or Theory?

Evolution is the process in which organisms change or adapt to better fit their environment and/or cohabitate/survive with the other organisms in their environment. I add the second part because organisms can evolve together. Last semester I took Organismic Biology, and I learned that moths and bats constantly evolve to outwit one another -- moths to stop bats from eating them, and bats to keep being able to eat the moths. Bats have developed echolocation to be able to find moths in the darkness of night. The echolocation sends sound pulses which bounce off objects/organisms and allow the bat to determine what the sound waves hit and its position. Moths came up with the ability to emit their own sonar to either block the bat’s waves or confuse it, and some moths developed the ability to send sounds that signaled that they were poisonous or would taste bad. This is an example of behavioral evolution, and the moths and bats have coevolved. Here is a link to a youtube video with more i...
Read more

Elephants and Evidence of Evolution

Image
       One of Darwin’s key predictions of evolution was that species change through time. This is dubbed as microevolution. When considering current evidence of evolution, I like to think about how humans have affected the evolution of other species. Most effects are done inadvertently. As I said in one of my previous posts, I love elephants. I remember reading a couple years ago that the amount of poaching of elephants in Africa for their ivory tusks has led to more elephants not developing trunks. Humans have poached and killed the elephants that have tusks to take their ivory, but they do not kill the elephants that do not have tusks. The poachers have thus selected for the tusk-less elephants. National Geographic reported that between 1977 and 1992, 90% of elephants living in a national park in Mozambique were killed for their ivory. Before 1992, 96-98% of female elephants developed tusks, but after 1992, only about 32% of female elephants developed tusks. Even m...
Read more