Natural selection was demonstrated in the Bird Beak Lab and the Hunger Games Lab because different traits were tested for their ability to help organisms survive and reproduce. There is also evidence of evolution that has been found today. There is the usual, fossils, and they physically show the change in populations over time. Also, they can be dated to see how old they are. Embryology, the study of embryos and their development, and evo-devo, comparing the developmental processes of different organisms, are also new ways that scientists have found to prove common ancestry and evolution. Homologous structures, similar bones with different functions, and analogous structures, different bones with similar functions, show that individuals have a common ancestor. Different organisms having analogous structures has occurred because of convergent evolution. This happens when two unrelated organisms develop similar traits because they have to adapt to similar environments or ecological niches.
A geologic timeline can show how life on Earth has changed over time. Earth was formed about 4.6 billion years ago. The time since has been divided into eras, periods, and epochs. There have been five mass extinctions, and we are now in the midst of a sixth. The four eras are the Precambrian, Paleozoic, Mesozoic, and Cenozoic. Then, the eras are split into periods. Life appeared in the first era, then the Cambrian Explosion. After that, it was the Age of Reptiles, and finally, us humans came into being. Earth has changed rapidly throughout its history, and humans have just arrived onto the scene. We are still making a big impact on the Earth itself. New species occur through speciation, which is caused by reproductive isolation. It can be behavioral, temporal, or geographical. Populations evolve through three different kinds of selection. Disruptive favors the extreme phenotypes, stabilizing favors the intermediate, and directional favors either one of the extreme phenotypes. Evolution continues to happen today, and it is important to learn about it because this knowledge can help us to deal with change when it happens in our world.
I want to learn more about the evidence that we have of evolution. It would be interesting to physically see fossils that show the changes over time, and see evolution that has taken place in past generations. This could be with analogous or homologous structures. I do not have any unanswered questions. I wonder about what will happen to our species. We have been on this planet for so little time, yet we have made so much change to this planet. I wonder if we will change what we are doing to try and help the planet instead of harming it. Everyone should become aware of what is going on in the world. I also wonder how our species will continue to evolve over time and if natural selection will play a role in our survival. Relating to assertiveness, I am mostly able to say what I want and speak about myself. I can probably become more clear with my priorities when I am doing something with other people. I can still continue to become more assertive while also listening to what others have to say, rather than dominating a conservation. That said, I should listen and contribute my own ideas that relate to what another person is saying. I can continue to become more confident in everything that I do and every situation.
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