Tyler's Post

My name is Tyler. I am in Mr. Thompson’s' fifth hour Student Naturalist class. In the little free time I do get the chance to enjoy, I mostly listen to music and hang out with my buddies. I also like to read.
I am going to be covering adaptations, genetic drift, and speciation of different animals such as Darwin’s finches, other animals, and even humans. I am not seeking to prove that the theory of speciation is fact, regardless of my own beliefs, but simply to inform the reader.
Adaptations happen in nature when an animal has a special ability that makes them better at competition, which is where animals compete for certain resources that are not easily ascertainable. An adaptation makes competition much easier for that animal, like the Western Hognose Snakes' fangs, which are located a little farther back in their mouths, and are used to literally pop some amphibians, such as some frogs and toads. Another example of this is the Gray Tree Frogs' adaptation to change colors, and to blend almost seamlessly into its background. It can blend so well that to most predators it is nearly invisible. Let’s say that an animal is hunting the Gray Tree Frog, and another frog. The predator is much more likely to pursue the other frog if it can't see the Gray Tree Frog, thus giving it an advantage. Not all advantages must be physical; however instincts or behaviors that only certain animals do are also adaptations. The Western Hognose, hen threatened, will bluff like it is very tough, and try to scare the predator off. If this fails it will turn over on its back and expose a red spot on its belly, and play dead. For a human example, the skin tones of different people around the world differ by the climate they live in. In Africa, the skin tones of the people are much darker than of those in Denmark. Now, this is not because the animals/people decided to adapt, or that their body decided to adapt. The reason that these adaptations occur is because of mutation. Now, the organisms with successful mutations breed with the other organisms of the species, and the species in that area becomes different, for the better, even though by chance. This leads to Genetic Drift, a term to describe how in different areas of the world, there are different organisms, and why in different areas of the world there are similar organisms with different adaptations. Darwin's Finches are a great example of this. Darwin examined at the finches on an island and discovered that they all came from a common ancestor. The important part was that on the island, there wasn't just one kind of finch, there were several. The finches that mutated and began to have longer beaks got better at eating grubs, and thus went to a different area to hunt grubs. They reproduced in that area, leading into a totally different kind of bird in this area that in the starting point. This happened several times to the finches, making several kinds. Another example would be the marsupials in Australia. They are similar to lots of the animals in the rest of the world, but somehow obtained pouches and look a little different. Their adaptions made them different, even though they probably had a common ancestor with another animal in another part of the world. Another Human example would be that in a place like Norway, the adaptation of dark skin would not help a certain person survive. Neither would a taller, skinnier profile. The people in Norway probably adapted to be stouter, where the people in Africa were more successful with their taller, skinnier profile. Their skin being darker also helped them to better suit their environment. Since it is more successful to be stout in Norway, and better to be tall and dark skinned in Africa, the two people's look very different today, even though it has been proven that all humans originated from Africa, from a common ancestor. Genetic drift, and specific adaptations that helped them survive in their environment led to this. The term for when one species becomes two or more species' is speciation. When Darwin’s' finches started as one species and ended up as several, it was speciation.

This is not one of the easiest things to prove in the Animal Kingdom, on account of the fact that it is not very observable. Things like speciation, like its broader heading Evolution takes a very long time to occur, and thus is difficult to prove. Genetic Drift it very closely associable to speciation. When Genetic Drift is where one creature becomes different because of separation of the species, speciation is the extreme of this. Speciation is when one species changes enough to where the common ancestor of a species is completely different than something that mutated from it. IF humans came from monkeys, than this would be an example of speciation, because they would be a completely different species. In some ways, speciation is the extreme of genetic drift, because genetic drift can cause speciation. A very well known example is the way that all dogs came from a common ancestor- the wolf. The wolf is a completely different species than the dog, or the many species' of dogs. This example can, in many ways, can be related to genetic drift as well, which comes from mutations and adaptations. In a way, you could say that mutations cause adaptations, which in turn can cause genetic drift. The opposite could also be said, however, that being separated can cause adaptations of the species to change in different areas, causing genetic drift. Either way, you could say that the cause of speciation can be genetic drift, so they make a chain, in which they all are related. Using the Human example again: A. A human adapts so that it is not so good in hotter climates, and is better in colder regions. Thus, it migrates to a colder area, being more successful there, and continues to change from the original human. Now, the two are completely different. B. A group of humans get separated from Africa and somehow end up in a colder climate. Some of them mutate and are better in this climate, and thus survive longer and reproduce more. In time, after further mutations, that part of the species is completely different than how it began back in Africa. This chain is not necessicarily what causes speciation or evolution, just one possible way that it can happen. This way of thinking of Evolution is much more reasonable than the way that many think of it. It is certain that if more people actually understood this process, they would be more accepting of it.
I'm not trying to prove anything, just to state a perspective on the issue. If something is learned through this, then I've accomplished my goal.


http://en.wikipedia.org/wiki/Genetic_drift

http://en.wikipedia.org/wiki/Speciation

http://www.talkorigins.org/faqs/evolution-definition.html

http://www.talkorigins.org/faqs/faq-speciation.html

http://www.wooster.edu/biology/mloveless/Drift.html