Adaptive Radiation

About Me: My name is Ashley. I am 16, and a junior at Olathe North. I play both clarinet and saxophone in the band. Music is my passion. My taste in music is differed. One minute I can be listening to Timbaland the next I will be listening to the Eagles "Hotel California." I am an only child and really wish I wasn't. Everyone always says that you are soooooooooo lucky but the truth is that I wish I had a sibling. The bad thing about being an only child is that you are constantly in the spotlight. Another bad thing about being an only child is that it is harder to communicate with people your own age. Talking to adults is still easier than talking to kids. I am a major sports fanatic. I have been to all the football game this year! GO EAGLES!!! I have been playing soccer since second grade and absolutely love it!
Adaptive Radiation as defined by the dictionary is," evolutionary diversification of a generalized ancestral form with production of adaptively specialized forms." Or for all the rest of us that speak English not Scientific mumbo jumbo it means species that undergo many changes over time. Another way of saying it is rapid specitation. The best example of this is us, because humans we are one of the most evolved species on this planet.
There are lots of examples of adaptive radiation in humans. The fact that we can walk on two legs is a adaption. Our hands have adapted to do specific tasks such as picking up things, the ability to squeeze things, and many other advanced things. Another example of adaptive radiation in humans is the advancement of melanin. Melanin is another name for skin pigment. There are many questions that can be asked for people to understand how melanin helps people survive in certain environmental areas. Would a person with black skin survive in Russia? Probably not! Would a white person survive for a long time in Africa? Probably not! This is why white people are usually in cooler places and why black people are in hotter areas and not the extremely cold places. That is how melanin is a adaptive feature of humans. Another example going along with the human body is the fact that our bodies gives an indication of the temperature in a certain climates. This is why we feel cold when snow is on the ground. This usually is helpful because it is an early warning sign for humans to get inside and start the fireplace. Many others animals, such as snakes do not have this luxury. Snakes can stay on a heated rock and not know it is hot and burn themselves. The last example I am going to give you about adaptive radiation in humans is the fact that humans have offspring, children, that are broader and smaller live in colder places while children in hotter places are thinner and taller humans. This is probably why there is so many people that are good at track in Kenya.
One the most asked questions about adaptive radiation is how is it caused? One of the causes of adaptive radiation is isolated ecosystems. Or in other words a place that is so separated there are not many species around. A type of isolated ecosystem that works well for adaptive radiation is mountain areas. It makes sense because not a lot of animals can survive those types of areas or even want to go up to those mountain areas. One of the examples of adaptive radiation is marsupials because they were isolated geographically, by a continent. This continent of course being Australia.


The main force driving animals is to stay alive and to make babies. The adaptive features that is best suited to their environment survive, while those animals that aren't suited to their environment will not survive. This is natural selection at its best. Mammals come from the same common ancestor. These common ancestors branch out with subspecies and become more and more diverse. When these subspecies become diverse they can no longer interbreed. Like a donkey and a horse. This happens because the animals become more and more separated from their common ancestor.The result of this is actually a good thing because it shows that animals are reproducing with certain heredity traits that are getting passed down to their offspring. Like the beginning of this paragraph the animal best suited survive the least suited die.
The best example of this of course is Darwin's finches. Darwin was a scientist that traveled to the Galapagos Islands. When observing the island he found these finches that looked the same but they really weren't. Each one of these finches became there own subspecies. The original finch was a seed finch these seed finches had babies and the hereditary traits in their gene pool to create different kinds of finches such as tool using finch, grubs, buds/fruit, leaves, and insect finch. These all came from the common ancestor: the seed finch.

The phrase that goes along with Darwin's finches is form is best suited for their function. The grub finch for example needs a long skinny beak to get into tigher places, such as logs. The Buds/Fruit finch needs a bigger stronger curved beak in order to crunch the fruit with their beak. The Buds/Fruit finch would also not want to have a smaller beak because then there would be no room to put the big fruit in its mouth. The tool using finch needs a bigger beak in order to hold the tool in its mouth. The insect finch also needs a small beak like the grubs finch in order to get its beak into to smaller places to get food. The Leaves finch has a medium sized beak because it really doesn't need a small beak or a big beak to get leaves. With this discovery of the finches the idea of evolution was starting to become more and more possible. There is one thing that the creationists and the evolutionists actually agree on that humans, like Darwin's finches, came from a common ancestor.
Here is an overview of the topics discussed. Adaptive Radiation is the basically the concept of speciatation. Creating subspecies from a common ancestor. Adaptive Radiation can happen many ways. One of these ways is an isolated ecosystems. An example of this is Australia. Another example of how adaptive radiation is after a mass extinction. There are many examples of adaptive radiation one of these being Darwin's finches. The phrase that goes along most with Darwin's finches is form follows function. This is shown from the seed finch, the common ancestor, in its gene pool creating new species of finches. These new species of finches is Buds/Fruit, Grubs, Tool Using, Insects, and Leaves finch. Adaptive Radiation is important to understand because it shows that Evolutionist and Creationist have a common link of understanding: a common ancestor.
Need More Info? Here is some links to get those wheels turning:
http://www.biology-online.org/2/15_adaptive_radiation.htm
http://en.wikipedia.org/wiki/Adaptive_radiation
http://www.pbs.org/wgbh/evolution/library/01/6/l_016_02.html
http://www.abdn.ac.uk/zoohons/lecture5/sld001.htm
http://en.wikipedia.org/wiki/Speciation