Geologic Timeline Individual Reflection

The first of the three major events that occurred is the formation of Earth. This is considered a major event because this is where it all started. There is not much evidence necessary for both an obvious and a significant event. The earth was created 4.6 billion years ago by the collision of dust particles until this grew into a planet. The creation of Earth is what allowed this all to happen. It is why I am able to type this reflection, and why you are able to teach me at all, let alone about the event. The second event we will be focusing on is the Cambrian Explosion. This was a sudden and rapid growth of a variety of organisms. The Cambrian Explosion is important because it was the start of many animal groups according to fossil records. This means that without the Cambrian Explosion, many of the life forms we have today would not exist. Finally, the end of the Cretaceous Period. The end of the period was brought by a mass extinction, which was caused by an asteroid about 6 miles in diameter. The mass extinction not only rid the Earth of about 3/4 of it's life, but it also opened the door to mammals. Before the extinction, dinosaurs ruled the land and only small mammals could survive in the beasts' shadow. However, the small mammals were some of the few that survived the collision, which allowed for evolution into larger mammals, and eventually us. These three major events all lead to the creation of mankind.

In our geologic timescale, 1 million years was represented by 2mm. When we first looked at this, we thought that we were going to have trouble measuring such small measurements. However, after we calculated the length of the each period, we discovered that the measurements would not be as terrible as I thought. What surprised me is the amount of time Earth went without any life at all, and then still took time for the Cambrian explosion to take place. What also surprises me is that such small events like asteroids colliding during the formation of Earth could change the course of the planet so greatly. Just imagine if an asteroid hit Earth during formation "the wrong way" or another hit causing a mass extinction. There would be a high chance we would not be here or Earth as we know it would not exist. It is beyond interesting just thinking about how perfect Earth is.

Human impacts on Earth have been great for humans. We have made life luxurious for ourselves. We have technology. No other known species has technology, let alone to our complexity and ability. However, in the perspective of nature and Earth, we are equivalent to the devil. We have taken from Earth and its resources without giving back. Humans have ruined Earth. It is a terrible reality, and there is always talk of changing, but there is no solution for years. Yes there are Teslas and solar energy, but that is lest than half a percent of what we need. Some scientists say we are already beyond the point of return.

I don't have any questions. I understood this unit and project rather well. The only thing is that there is so much to think about. Like I said previously, there were so many possibilities for Earth's life and path. How did Earth become what it is today? What stopped another asteroid from hitting Earth or falling into its orbit and becoming a second moon?

I couldn't get any quality photos of my own timeline, so I will post a photo of a geologic time scale in general.
      

Unit 8 Reflection

This unit was all about Evolution. We were first introduced to the unit with a vodcast on artificial selection, and in my opinion, it is summed up in one sentence: Artificial selection is survival of the fittest based on skewed criteria, which is based on human needs or desires.  This breed is a product of artificial selection to improve its speed and look.
 We were then introduced to Darwin, who laid down the foundation of the study of evolution. Darwin made observations and then conclusions which allowed future scientists to make the progress they have made. We then learned about evolution, specifically natural selection and the gene pool. Like we know, natural selection is survival of the fittest, and the gene pool is what the population is made up of. However, the most significant topic is what evolution is. Evolution is a change in allele frequency. Speciation is literally the process of creating two species. It is the visual effect of evolution. It is when two populations of the same species grow beyond capable of interbreeding with each other. In other words, they have become 2 new species from that one original. After we leaned what evolution was, we learned about the proof that evolution was true. We learned about embryology, evo-devo, vestigial structures, fossils, analogous/homologous structures, and convergent evolution. Out of all of these processes, the strongest evidence we have in support of evolution is vestigial structures. It is literally visible proof of how populations are in the midst of evolving beyond the use of some bone. However, the evolution has not completely occurred, which is why the structures still show up in some organisms only. The weakest evidence we have, in my opinion, is fossils. Although fossils tell a story, it is too easy to miss a chunk of information/history because one year or one generation didn't fossilize correctly or completely. Evolving populations was all about the types of evolution that occur. There are 5 main types: natural selection, sexual selection, mutations, genetic drift, and gene flow. However, gene flow stops evolution from occurring, as it is the movement of organisms between populations. This means that the organisms still breed with each other and speciation does not occur. The most interesting one is genetic drift. It is when an unexpected disaster strikes and put a dent in a species' population. This also leaves who survives up to chance, so it is not always that the superior trait with survive. We lastly learned about the history of life on earth. This was an interesting vodcast, because even though we learn about the eras in every science class, this is the first time I learned about and RNA based world. I did not realize how important RNA was. I though it was simply RNA, but I would have never guessed it would help create the world we live in so dramatically. 
In the middle of learning all of this, we did a couple of fun labs. We did the bird beak one which showed the best bird beak out of a spoon, scissors, tweezers, and a binder clips. It was obviously the tweezers. However, the best lab was the Hunger Games Lab. This lab really made evolution of a population clear. The population grew, shrunk, changed in allele frequency, and many other things. This was also the most fun lab.

The only question I have left is: Where do the new alleles come from in the first place? I understand the original, and how evolution occurs, but where does that new or different allele in the allele frequency change come to be?

I really enjoyed this unit because I am very intersested in evolution and animals. I love studying about what once ruled the planet and what happened. In my opinion, this was my best unit yet on understanding the concepts and participating in class. I was active every class and was doing all my assignments to the best of my ability. I think I did well in being assertive and not aggressive, especially when it came to the Geologic Timeline. This was one thing I wanted to continue to work on. Of course I will still work on it, but I would really like to focus on my studying techniques. I felt confident on the test and did not study as much as I should. Even though I didn't have any problems with the test, it is not a good study habit to not study because you think you know everything.