The process of evolution reminds me of the different ways humans over time have had to adapt to their changing surroundings, evolving with their environment.  For example, people who live in Saskatchewan, Canada, experience all four seasons.  Over the years they have learned to adapt to all these environmental changes for survival.  An example of this is that they have acclimatized to their weather.  It can be -10*C one day and then -25*C the next.  They have gained a higher tolerance to these extremes of weather in order too survive.

I only have a brief understanding of this topic, so I did some research to learn the specifics of it.  I learned that for us to acknowledge that evolution has occurred, is to realize that all living things are connected by common ancestry, making them united.  They have also diversified over time so they can adapt to the specific demands of the environment they live in.  It is believed that the last common ancestor to all existing life forms lived about 4 billion years ago, so there has been plenty of time for evolution to diversify these organisms into the forms that they have taken today.  Evolutions major driving mechanism is natural selection, which is a theory proposed by Charles Darwin.  Natural selection is a process where organisms that are better at adapting to their environment, tend to survive longer and produce more offspring.

Example of natural selection:

  1. The traits vary
    Some beetles are brown, while some are green.
Color variation in these beetles

 

  1. Differential reproduction.
    The environment is unable to support unlimited population growth, so not all organisms get to reproduce to their full potential. In this example, green beetles are more sought after by birds to be eaten. It lowers there population and they reproduce less often than brown beetles do.
Differential reproduction
  1. Heredity.
    The surviving brown beetles have brown baby beetles because of their genetics.
Heredity of the traits of the beetles who survive
  1. End result:
    With the brown beetles having the advantage of their color, the brown beetles are able to have more offspring. Making them more common in the population. If this continues, eventually all beetles in the population will be brown.
Eventually, the advantageous trait dominates

Evolution is important because it helps us understand and solve biological problems that impact our lives everyday.  The field of medicine is an excellent example of this because scientists must understand the evolutionary pattern of organisms that cause diseases, this way we can stay one step ahead of pathogenic diseases.  Also for us to be able to control hereditary disease we must understand the history behind genes that cause diseases.

Questions I have:

-Is there an ‘end point’ for evolution?

-What are some of the traits that all organisms share from our last common ancestor?

-How is evolution able to produce complex organs like the eye?

Facts I found interesting:

-Not all physical traits are adaptions.  Vestigial structures are just leftovers from previous ancestors, and have no function at all in modern descents.  In humans an example of a vestigial structure is the appendix.

-The last common ancestor to all existing life forms lived 3.9 billion years ago.  This ancestor gave arise to the three domains of life- Eukarya, Bacteria, and Archaea.

-The theory of natural selection supports the idea that man was evolved and that he was not created.

 

 

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