This Is My Selection (Blog #4)

Describe the three types of selection: directional, stabilizing and disruptive and give an example of each in your own words
Directional, stabilizing, and disruptive selection are the thre types of natural selection.
Directional selection is where a single trait is favored causing the frequency of the trait being dominant greater. The trait maybe recessive but with directional selection the recessive trait is favored so eventually it will become fixed.

             
 An example of directional selection is the fast trait in hunting dogs. Dogs that hunt need to be fast to catch their pray so their genes began to allow them to be faster and faster.

Disruptive selection is where two extreme sides of a trait are favored over the intermediate trait. This means that the differences in the trait are very obvious, which creates two different species that grow in different directions.

An example of disruptive selection is the galapagos finches.

Stabilizing selection is where the diversity of a trait decreases and the species has the same trait.

An example of stabilizing selection is a syberian huskie.

Blog #3

Explain what microevolution is? What are the three ways that variation occurs?
Microevolution is evolution an a small scale within a single population. It cannot always be seen in a species, it sometimes only effects how a species survives.
The three ways the variations occur are through mutation, gene flow, and natural selection.
Mutation is where some genes randomly mutate into different genes.
Gene flow, or migration, is where different genes enter a population through reproduction.
And natural selection is the idea that the strongest survive and the weak genes die off.

Blog #2 Fossils

Fossil records are hard to interpret because no two fossils are the same. Fossils come in many different sizes, shapes, and qualities. Some fossils have many pieces missing, that makes it very hard for scientist to determine what the species was and what its ancestors were. And without the fossils being the same shape or size scientists may not be able to put together that the two species are similar or related. Also if a fossil is small it can be damaged making it hard to interpret.   

http://www.thedarwinpapers.com/oldsite/number5/darwin5.htm

Blog #1 Evolution

 Evolution is not a law because laws can be tested in a lab and be proven completely true. A scientist cannot go into a lab and reproduce evolution in a test tube or in a box. Evolution took thousands if not millions of years to happen. Plus the mechanisms behind evolution are not widely excepted.