In the book, Before the Dawn, Nicholas Wade writes about human evolution and answers many interesting questions about how we came to be as a species. One of the things he talks about is how humans lost their fur. When humans first split off from chimpanzees, they looked much more like apes than humans. However, this changed once Homo ergaster came to be. Ergaster was the first human ancestor to have an external nose and have "nakedness". Some paleontologists believe that this nakedness came from their need to sweat. It is impossible for a creature to sweat efficiently if it has fur, so it would make sense for ergaster to shed its fur in order to cool its body and bigger brain. Conversely, other scientists proposed that human ancestors lost their hair as a consequence of sexual preference. One theory behind this preference is that they would be less likely to have parasites and bugs on them if they shed their thick fur, making sexual encounters a little less risky. Darwin was a big proponent of sexual selection, and he really pushed the idea that humans preffered mates without pests crawling on them.
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On Monday, I did a lot of stuff with my friends. After my Plant Physiology class, me and my friend met up at Blue Wall to eat lunch. We hung out at Blue Wall for about an hour until he had to go to class. Once he left, I went back to my dorm to take a nap. After my nap, a couple of my friends came over and we played Xbox together for about an hour. After we got bored of playing Xbox, we went outside and played basketball on the outdoor basketball courts in Southwest. We played basketball for about one and a half hours and then went to Hampshire dining hall to get an early dinner. After we ate, we all went our separate ways to go home and shower. Later that night, me and my friend Ben went to the library together to do some homework.
The article Origin matters: widely distributed native and non-native species benefit from different functional traits had similarities and differences to the previous article. Similarly, this article has level 2 headings that include introduction, methods and materials, and discussion. There are also some subheadings that help the author divide up the different elements of the methods, like “Trait selection” and “Trait interaction models”. The divided subsections helped make the paper easier to follow. Just like the previous article, in the beginning of each section, there is an introduction paragraph that shows the reader what the section will entail. However, in this article, one of the introduction sentences to these introduction paragraphs has a rhetorical question. This article was concise and had good flow, however it did not flow as well as the other article. This article follows the IMRAD format exactly.
In the article, Non-native species and rates of spread: lessons from the brackish Black Sea, there are mostly level 2 headings. These headings include the usual headings, like abstract, discussion, and acknowledgments. In addition to that, it contains other level two headings, like “Rate of secondary spread within the Black sea” and “Vertical spread”. These headings provide more specific sections of the results piece of the article. The first paragraph of the introduction section starts out broad to get the reader engaged and then it gradually becomes more specific. However, in the individual sections that include the results of the experiment, the information does not start out as broad. In these sections, the author jumps right into the data. This article follows the IMRAD format that was described in chapter 7. At the beginning of most paragraphs, there is a topic sentence which informs the reader what the author will be discussing. This is especially helpful when the author is describing different species in the results, like B. improvisus and P. antipodarum. Finally, this article had concise paragraphs with good flow, similar to the examples that were given in chapter 3.
The movie Gattaca follows a “genetically inferior” man named Vincent Freeman in his pursuit to live the life of a “genetically superior” man named Jerome Morrow, so that he can achieve his dream to go to space. Gattaca has a very interesting premise, it is set in a world that cares more about your genes than how hard you work or what your religion or race is. Although it had some cheesy dialogue and some plot holes, it was still a much better movie than I was expecting it to be. In addition to that, the society that this movie is rooted in was very interesting to watch considering the material that is being discussed in class.
In this movie, normal births are no longer normal. In Vincent’s case, he was born normally without any genetic editing. Upon being born, the nurse takes a blood sample from him and is able to tell when he will die, his propensity for disorders, and that he has a heart condition. This is funny to see, because the free fetal DNA testing that is used in real life today requires much more time to process in order to find much less information about the infant. In the movie, scientists prepare viable zygotes and allow the parents to choose what they would want their child to be like. When Vincent’s parents went to go “design” Vincent’s brother, the scientist had already removed the risk of alcoholism, obesity, and other bad traits, which was a shock to the parents. If this was the case, there would be less need for blood tests like the ones that look for cancer, because people could be designed to be at a lower risk of cancer. In today's world, parents take the random genetic variety of their children for granted. In the pursuit of attaining children without disease, parents lost the randomness of what their child would be like.
When a couple is expecting a child, they wonder what gender it is and what defects it could possibly have. In the past, the best method to answer these question was a procedure called amniocentesis. Amniocentesis is a technique where a needle is inserted into a women’s amniotic sac through her abdomen in order to collect amniotic fluid which could then be analyzed. This process gives results with a high degree of certainty, however it has some flaws. Since a long needle is being injected into the womb, there is the risk that it could poke something that it is not supposed to. Therefore, there is miscarriage in about 1% of amniocentesis patients. That being said, there is now a new method of determining the genetic information of the fetus, and it is much less invasive. The new test goes by the name of free fetal DNA testing, and all the mother has to do is get blood taken. By collecting the blood of the mother, companies like Harmony can separate out the fetal DNA and examine it to find birth defects and determine the gender, to a lesser degree of certainty than amniocentesis. The blood of the fetus and the mother do not directly mix, however, the placenta sheds tissue into the mother’s blood stream daily. Because of the placental shedding, fetal DNA can find itself leaking into the mother’s blood stream and mixing in with her blood and loose DNA. Once the scientists collect the blood sample of the mother, they then need to separate the fetal DNA from the mother’s DNA. Scientists have discovered that the fetal DNA fragments are much smaller than the mother’s DNA fragments. Using this knowledge, they use electrophoresis in order to separate the DNA fragments. In electrophoresis, the molecules are dragged through a gel matrix using an electric current causing the DNA fragments to arrange themselves by size. Once the fetal DNA fragments have been identified, they can then be used to determine things about the genetics of the fetus.
After thirty minutes of observation with the creature, I compiled a list of notes that describe the organism. The organism is a larval creature, looks like a maggot with a rat-like tail. It has a pale green brown translucent layer of tissue on its main body segment that is about 1.25 cm long and 0.25 cm thick. It was hard to record an exact length, because the organism contracts and extends as it moves around the bowl. The creature has dark lines that run from a dark mass in the head of the creature to the tip of its tail. On the underside of its body, the larva has a mouth at the front that it opens whenever the organism moves. The organism has bilateral symmetry, as seen by its eight legs and two antennae on its head, which it probably uses to read its surroundings, as it does not have eyes. The larva’s tail is dark green in color and is 1.5 cm long and 0.5 mm thick. The tail is probably used for the larva to breath when it is feeding underneath a surface where there is poor oxygen.
The subject is a larval looking organism that is moving around. It was placed in the bowl along with some wood chips, which would lead me to believe that it prefers to be buried in the wood chip material. While it looks like it is trying to eat the woodchips sometimes, it is not trying to eat them. It has as pale green color with dark green lines on its main body segment that is about 1.25 cm long 0.25 cm thick, however that length varies as the organism changes shape when it moves. As it moves in a circular pattern around the bowl, I can see its white insides moving around as the pale green color comes from a somewhat translucent tissue layer on top of its inner organs. The entire body is covered by this translucent layer except for the tip of the tail. The dark lines that go throughout the main body segment looks as though they could be an organ system instead of just for decoration. The head of the organism has a lot of the dark coloration underneath the pale green layer of tissue. Perhaps the dark green is part of nervous system or circulatory system. It also has a dark green tail of some kind that is about 1.5 cm long and about 0.5 mm in thickness. It moves in a way that is very similar to a caterpillar. It seems to lead its motion with the opening of its mouth and then contracts its body and extends it. When looking at the underside of it, it has 8 pairs of “legs”. In addition to that it has a mouth on the bottom of its body at the front of the main body segment. When I touched the organism to move it to a place it could be measured, it had a very soft touch to it and felt very fragile. Whenever I touch the organism, it seems to freeze up for a couple seconds. Once I stop touching it, it resumes moving around the bowl.
One thing that I would want to know is what the creature would eat. If I put the organism on a leaf, would it eat the leaf? In addition to that, I am curious where it prefers to live. If I put it in an environment with dirt, would it try to burrow down to find safety? Or is it used to being up in a tree and munching on leaves? Ideally, I would try to let it grow up into its adult stage to figure out what this organism is the larval version of.