EVOLUTION

 

Watch/Make Notes:

 

Under what conditions does evolution occur?

Evolution occurs when there is an abundant of resources and missing niches for an organism to take advantage of.  Evolution is the change in the frequency of a gene.

 

 

Why do some species change so rapidly?

Some species change so rapidly because of the theory

of punctuated equilibrium. The theory of punctuated

equilibrium states that most evolutionary changes happen in

relatively rapid spirts of change and that follows a long

period of little change. Punctuated Equilibrium happens

when a species is exposed to an environment that changes

rapidly. Or even after a mass extinction event because there

will be less competitors. 

 

Why do other species stay the same over millions of years?

Other species stay the same because they are in an environment that changes slowly. It follows the theory of gradualism which is a theory that says large evolutionary changes species is because of the accumulation of many small and ongoing changes. In the case of the shark, it is an environment where it is in charge. The shark is referred to as the king of the ocean and is already the most dominant species in the ocean. For it, the environment doesn’t really change and it has an abundance of resources over those millions of years which allowed it to stay the same.

 

The 5 Fingers of Evolution: http://ed.ted.com/lessons/five-fingers-of-evolution

• Natural Selection

• Population shrinking (chance will take over)

• Mating (mating of individuals with different genes can change frequency of genes)

• Mutation (a mutation in the DNA can affect the frequency of a gene in the gene pool)

• Movement (organisms moving in and out the area can change the frequency of a gene pool)

 

How does this list compare to the one from your textbook (p.333)?

This list is basically the same as the conditions stated in the Hardy-Weinberg principle. 

 

Reflect/Journal:

I was surprised to learn about how important the Hardy-Weinberg principle actually is. The textbook gives about half a page to the Hardy-Weinberg Principle but considering the conditions discussed in the principle actually drive evolution, I feel that it can be discussed a bit more. The transitional form of a land and water animal that I saw in the video shown in class was easily the most unique animal I have ever seen.  One of the things that really excite me are missing links because that makes me think deeply about an issue and I feel like I could be the one to fill in that missing link. I don’t think that the videos in this chapter were really relative to chapter 8.5. I felt that the video was more relevant to 8.1. One of the questions that I really want the answer to is where life came from, where did the original cell come from? Hopefully that question will be answered in my lifetime.