Wednesday, September 15, 2010

Camouflage Final Draft

Chelsea Borek
Kerr
EN101-5
9/15/10
Camouflage
Camouflage is a method found in nature that allows an organism to blend in with its surrounding environment.  This technique is used avoid observation through deception. By blending in with the environment, an organism can often escape detection from predators. In this way, the organism can survive longer and potentially reproduce, thus increasing the population of its species.
Animals produce the colors to match their environment through biochemical processes. Biochromes are natural pigments found in the body of many animals that produce color. The chemical make-up of color pigments allows them to absorb some colors of light and reflect others. The color of a living thing is a combination of all the visible wavelengths of light that are reflected from it. An example of this is polar bears. The translucent hairs of a polar bear create their white coloration that we see. Their skin is actually black, and when light strikes the curved hairs, some is absorbed into the surface of the skin, and the rest is reflected out.
Animals can also produce an accidental camouflage. In some cases, caterpillars are green due to their diet. Their blood absorbs the chlorophyll from their food, giving them their green coloring that matches their leafy environment. A South American sloth can acquire a greenish coloration because of symbiotic algae that lives on its fur. This helps to hide the sloth as it lives and sleeps in the trees.
Mimicry is another form of camouflage. Mimicry is the ability of an animal to copy a pattern of another animal in order to confuse a potential predator. The Viceroy butterfly uses mimicry by having similar colors and markings as the poisonous Monarch butterfly. This deceives birds that would otherwise eat the Viceroy butterfly because it makes them appear poisonous. 
There are many factors involved in an animal’s camouflage. The main element is the environment in which the animal lives.  An animal that lives in the forest would not have the same camouflage as an animal living in the ocean. For example, deer are a brownish color that blends in with the browns of a forest’s trees and soil, while dolphins are a grayish-blue color that camouflages them with the water.
 An animal that is effectively camouflaged in one environment would be extremely noticeable in another environment. Animals of the tundra all have white fur that would stand out among the trees of a forest.  Polar bears, rabbits, and foxes all blend in with the snow. This allows the predator to be less visible as it stalks its prey and allows the prey to hide among the snow banks.   Animals in the same family often have very different coloration that has developed over many years. Besides the polar bear, there are both black bears and brown bears. Both of the cousins of the polar bear live among trees so a darker color provides a more effective camouflage. 
Camouflage is important for survival. An animal that has camouflage is more likely to survive and reproduce then an animal that lacks camouflage. Over generations, the camouflaged animals increase in population. Camouflage as a method of adaptation is a key factor of natural selection. Natural selection was first explained by Charles Darwin in his theory of evolution.  Darwin noticed that animal populations depended on “survival of the fittest,” and survival often depended on the ability to remain hidden.
As humans have evolved, they have often impacted the environment of other organisms.  The peppered moths have proven to be an excellent subject for observation because scientists have noticed an adaptation resulting from a change in their environment.
Before the Industrial Revolution, the peppered moths were mostly light colored, which effectively camouflaged them against the light colored trees. The moths simply landed on the trees for both resting and reproduction. Occasionally, a moth would be born with a darker colorization. This type of moth was so visible when it landed on the trees that they were readily caught and eaten by birds. This prevented the darker colored moth from reproducing and reduced the dark color in the gene pool.  
After the Industrial Revolution there was a noticeable decrease in light colored moths and an increase in dark ones. Around this time, there was an increase in the human population and a subsequent increase in factories. The factories created layers of soot that covered the light trees and tuned them dark grey. This meant that the light colored moths were now very visible to the birds and the dark moths were camouflaged. Since the dark moths were now effectively hidden from the birds, they survived long enough to reproduce and pass on the dark color genes to their offspring.  This slow change in camouflage is a classic example of adaptation.
All organisms are genetically predisposed to reproduce and thereby insure the survival of their species. Camouflage has proven to be an effective method of allowing living things to blend in with their environment so as to escape detection and deceive predators.  Though this natural process has been quite successful for many species, humans have begun to drastically alter their environment and destroy the natural covering that has made camouflage so effective. Many species are undergoing the evolutionary process to create a new camouflage. Unfortunately, some species have not been able to adapt quickly enough to avoid extinction. It is important to recognize the significance of camouflage as a life-saving adaptation for many living things before making drastic changes to our environment.







Works Cited
"Charles Darwin | Naturalist." Lucidcafé Interactive Café and Information Resource. Web. 13 Sept. 2010. <http://www2.lucidcafe.com/lucidcafe/library/96feb/darwin.html>.
 "Chemistry - Camouflage." Chemistry Daily - Articles on Every Chemistry Topic. Web. 10 Sept. 2010. <http://www.chemistrydaily.com/chemistry/Camouflage>.
"Science: Natural Camouflage - TIME." Breaking News, Analysis, Politics, Blogs, News Photos, Video, Tech Reviews - TIME.com. Web. 10 Sept. 2010. <http://www.time.com/time/magazine/article/0,9171,884415,00.html>.
So, By Doing. "Insect Camouflage and Mimicry - National Zoo| FONZ." Welcome to the National Zoo| FONZ Website - National Zoo| FONZ. Web. 13 Sept. 2010. <http://nationalzoo.si.edu/Animals/Invertebrates/Facts/insects/camouflage.cfm>.

2 comments:

  1. this draft is soooo legit, wish i was smart enough to do this

    ReplyDelete
  2. The information about the caterpillar was very interesting.

    ReplyDelete