In week 2, I learned the "Selection in Action" video content. This is the link http://www.hhmi.org/biointeractive/selection-action. The content is about comparing the artificial selection of dogs and corn with the natural selection of the stickleback fish.
Darwin's key analogy said that artificial selection by breeders can produce major changes in body form:
variation
l
choose particular animals to produce
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develop new breeds with increase or decrease in particular trait
Artificial selection has produced the food we eat and the pet we keep.
1) transformation of wild teosinte into modern corn
2) wolves into dog
History of Life
History of Life - Part I
HOW DID LIFE BEGIN?
Life started about more than 3.8 billion years ago is almost non-existent and then have inorganic molecules. After that, organic molecules start to live from non-organic matter through a natural process on a pre-biotic earth which is called chemical evolution. Then, the organic molecules start to evolve into more complex life forms through a natural process of random mutation and natural selection.
Prebiotic broth hypothesis
Miller-Urey's experiment has established how organic molecules formed on primitive earth. So, once earth cooled this molecules start to form.
Polymers evolved from small molecules into large molecules as the first genetic material formed was RNA which can self-replicate then evolved into DNA. RNA also evolved into protobionts and after that prokaryotes and eukaryotes formed.
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