Evolution

This week in AP Biology we talked about evolution. Evolution is a very interesting subject. Learning about common ancestors that a species has and how the species has evolved over time. Charles Darwin was one of the first people to really go in depth about evolution. He traveled around the world on the HMS Beagle and during his travels he stopped at the Galapagos Islands and started studying all of the species and fossils that lived on the island and noticed that some species had similar characteristics as other species he has seen before. Homology is when there is a similarity in characteristics resulting in a shared ancestor which is what Darwin saw. Vestigial structures is when there is a structure that is useless to the organism. For example in the Galapagos Islands there is a flightless bird called the cormorant, but there is a cormorant that can fly, but it is not in the Galapagos Island. Both are the same bird, but one can fly while the other cannot. The reason being is because the cormorant in the Galapagos Islands does not have a need to fly, since it is surrounded by water, it dives and swims for it's food. While the cormorant that can fly depends on its wings for food and other necessities. Evolution is a very interesting subject to learn about and so far it is my favorite topic this whole school year.