Human Variation & Race

High levels of solar radiation

1.      High levels of solar radiation are an environmental stress that negatively impacts the survival of humans by disturbing homeostasis. Early hominins lived in the tropics where solar radiation is more intense, they spent their days outdoors, and didn’t wear clothing that would have protected them from the sun. Under these conditions, UV radiation was a powerful agent selecting for maximum levels of melanin production, which protects us from overexposure to UV radiation, in early hominins. However, it was shown that all albinos in dark-skinned populations had either precancerous lesions or skin cancer by the age of twenty. This evidence shows that even in early hominins of reproductive age, less-pigmented skin could have reduced individual reproductive fitness in regions of intense sunlight. Also, some studies have shown that UV radiation rapidly depletes folate serum levels both in laboratory experiments and in light-skinned individuals. These findings have consequences for pregnant women, for children, and for the evolution of dark skin in early hominins.

2.      Humans have adapted to high levels of solar radiation by developing dark skin as a protective response to the damaging effects of UV radiation.

3.      The benefits of studying human variation from this perspective across environmental clines are to show us how we came to be the way we are today.  There are reasons why humans in different areas have certain behaviors and characteristics and it can help us understand how more about ourselves. Information from explorations like this can be useful to help us in many ways such as learning from others’ experiences and perspectives. If one person gets the chance to explore an area while bringing back what they have found and experienced, we have one more way of gaining knowledge about something. This information can be used in a productive way by showing us new developments and cultures, as well as finding out new ways of life.

4.      I would use race to understand the variation of the adaptations by studying physical traits as well as cultural attributes. However, the study of environmental influences on adaptations is a better way to understand human variation than by use of race because instead of thinking of race as a physical attribute, we can think of race as a species. This way seems to be more promising, and gives a clearer and more detailed study.

Language Blog Post

This assignment was not easy, and I can’t imagine any person being able to do this without hesitation, frustration, and brief moments of giving up. I had to sit with different people several times, trying to figure out a way to communicate. I was not able to speak, write or use sign language. This made me feel almost naked to have one of my learned behaviors taken away from me. I could feel anxiety whenever I imagined myself not being able to use symbolic language in order to communicate on a regular basis.

My partners had no idea that I was doing an assignment that would not let me use symbolic language in order to communicate with them. Some partners made jokes at how I was acting until what I was doing because the topic of the conversation. One person stopped talking to me completely because they thought I was being rude or making fun of them. However, one of my partners tried communicating at the same level I was and we actually became pretty successful.

If I were to imagine that my partners and I represented two different cultures that had met for the first time, I would give only one culture some great advantages in communicating complex ideas. The culture that would be able to express symbolic language would be able to use language to explain what they are saying and how they feel, but another culture would have no idea how to interpret this. On the other hand, a person who is not able to express themselves with symbolic language can find a way to communicate with people regardless of their culture. They don’t need to understand each other verbally or symbolically because they are speaking a language that does not exactly need to be learned. I would have to say that people who can communicate without using symbolic language have a better chance of communicating complex ideas to other cultures because they have a variety of ways to communicate in order to get their point across that seem to be more understandable to some one who does not speak their language.

Individuals in our culture that have difficulty communicating with spoken language may have a hard time relating to other people. They are known as handicapped, might even be put into different schools, and could be out casted from certain environments. I have a friend who is deaf, and from what she has told me, it is hard to make friends with other people who do not know sign language. She says that most people avoid talking to her because they are impatient and don’t want to try. It might seem like common sense, but many people do not know that deaf people have trouble speaking to others as well as hearing others. It helps that she is able to text people through her phone and computer, but at the same time, she is still rejected from so many people and things because of her disability. She is not able to go to school unless she pays extra money for a specific program, and she has also never had a job. I took sign language classes in order to communicate with her, but we also text because I am not fluent. Some other ways we communicate with each other are using our hand gestures and facial expressions.

I honestly was not able to last fifteen minutes of speaking without being able to use any physical embellishments. This experiment was difficult for me because I naturally use my hands, and face, and tone of voice to show how I feel about what I am talking about. Without being able to do this, my partner had no idea whether I was serious, sarcastic, rude, or friendly. There were a few times when my partner became offended because he assumed I was insulted him when I was actually joking. There was also a time where I became offended because when I was speaking sarcastically, my partner assumed I was being serious and said something serious back that hurt my feelings. This is why we did not last fifteen minutes.

My partner was affected in a negative way because he kept taking things that I was saying the wrong way. I either was insulting him, or was not interested in what he was saying due to not being able to speak enthusiastically or show any facial expressions. He ended up not speaking to me for an entire day until I finally was able to tell him that the way I was acting was for an experiment in one of my classes. I didn’t want to tell anyone that I was performing an experiment until afterwards in order to get a better result.

This experiment says a lot about our use of “signs” in our language. Using signs is just as important in communication as language, if not more. Sure people will be able to understand what we are saying, but without and signs, they will not understand the way we are saying something and might get a completely different idea of what we are telling them.

I believe that many people have difficulty reading body language. Dating is the most common example of how people can find it difficult to read a person’s body language. On a first date, a man tries to kiss a woman because he thought the date went well. Little did he know that her legs were crossed away from him the whole time, she kept excusing herself to go to the restroom, and texted on her phone most of the night while giving him a few courtesy laughs. There are benefits to being able to read body language such as being able to figure out when the right time to talk to your boss is about the vacation time you would like to take off. Also, it helps you determine whether a person is interested in you, so you know that it is okay to ask for their phone number. There are many advantages to reading body language, and in my opinion, having this ability makes life much easier. I can not see how not being able to read body language can benefit a person, except maybe to not let the way certain people’s thoughts affect you. Body language can show how a person feels about you, and this might distract or upset you if the body language is negative.

Piltdown Hoax

The Piltdown hoax started with an archaeologist named Charles Dawson who found what was thought to be the remains of a human skull in the village of Piltdown in 1912. As more bones were recovered by Dawson, Arthur Smith Woodward, and Father Pierre Teilhard de Chardin, who he had brought along, realized that they were the fossils of the link between apes and humans. People were suspicious but kept their opinions to themselves because they were afraid to challenge Dawson’s physical proof. For others, this became concrete evidence of human evolution.

Ancient remains were also discovered in Asia and Africa, but these fossils were not similar to the ones found in Piltdown. After realizing this, specialists were sent out to review the materials found in Piltdown, showing that the remains weren’t as old as suspected, showing that they were less than one hundred years old. The staining on the bones was superficial, the material was cut while fossilized with a steel knife, and there was evidence that the teeth had been filed down. It had been discovered that these remains had come from a female orangutan. Scientists were stunned when they came to the conclusion that somebody had forged the Piltdown fossils. Not only that, but Charles Dawson became the main suspect.

Scientists are just as human as anyone else and can be just as dishonest and deceiving as the rest of us. Humans share certain negative qualities such as greed, the need for power or fame, and letting opinions get in the way of searching for facts. In this scenario, Dawson was an amateur archaeologist, possibly looking for something to advance his career. He wanted to be powerful and known for something amazing such as proof that humans evolved from apes. His greed may have gotten the best of him when he found fake fossils that he had supposedly planted himself. Instead of looking for facts to support his opinion, he created his own “facts” to get others to believe in his theory.

The positive aspects of the scientific process that were responsible for revealing the skull to be a fraud were technologies that measured the fluorine content in order to date the fossils after WWII in 1949, the first full scale analysis that scientists launched in 1953 in order to get a more accurate date of the aged fossils, and microscopes that determined that the teeth were shaved in order to make a certain shape. I don’t think it is possible to remove the “human” factor from science to reduce the chance of errors like this because I don’t believe that humans can just remove their thoughts, feelings, and qualities entirely. I think that scientists are going to make errors due to being humans, and others will most likely discover these errors just like what happened in Piltdown.

I am not sure if I would want to remove the human factor from science, but it would probably be a good idea so that we are able to get solid facts instead of being conned into believing a scientist’s opinion just because he or she is a scientist. The lesson that I can take from this historical event is that lying can affect a lot of people, that scientists are human too. They make mistakes, lie, and are vulnerable to the same things we strive for such as money, fame and power. Also, I have learned that it is best to find your own proof and to not be afraid to challenge things that you are skeptical about, even if someone of higher power and intelligence states it as fact.

Comparative Primate Blog Post

Lemur

The Lemur lives in forest areas, more common in tropical rainforests, but some can be located in dry areas as well as savannahs. The lemur dentition has multiple tooth morphologies. In most lemurs, the bottom incisors and canine teeth come outward instead of facing up and are spaced out, providing a tool for grooming and feeding. Lemurs have their full permanent dentition when they are still being breast-fed. This trait is viewed as an adaptation to the lemurs’ environment showing that their teeth are perfectly adapted for shearing leaves and crushing seeds. Their spaced out, procumbent teeth make them capable of grooming and prying out large seeds from fruits. They are also able to cut through tree bark in order to feed on sap. Their dentition helps them survive in the forest areas that they live in.

Spider Monkey

Spider monkeys live in tropical rainforests where they thrive in evergreen, semi deciduous and mangrove forests. These monkeys live in the highest parts of the trees found in rain forests and prefer undisturbed forests. Spider monkeys have three premolars. These monkeys are capable of eating seeds, flowers and nuts, but their main diet consists of fruit, swallowing them whole. The male teeth are much larger than the female’s teeth causing them to be the providers for their families. Their teeth are small and sharp, ready to chew on the tough seeds and nuts that are common in their environment. Their teeth also help them adapt to retrieving the fruits that grow on the high branches, helping them hold onto their food as they climb back to their home.

Baboon 

Baboons have a wide tolerance for habitat and are extremely adaptable. However, they prefer to live in trees while climbing down to hunt for food. They like open woodlands, savannahs, grassland, and rocky hill country. All baboons have long muzzles, heavy and powerful jaws with sharp canine teeth. This helps them chew their food while feeding off of small animals. However, they eat a variety of foods such as leaves flowers and seeds. This trait is an adaptation to a baboon’s environment by being able to feed off of animals when there are no plants available, or being able to eat plants when animals cannot be hunted.

Gibbon



Gibbons live in the deciduous and evergreen rainforests of Southeast Asia and are very rarely observed on the ground, keeping themselves safe from most of their predators. The gibbon eats fruit, leaves, insects and flowers. The dental arcade is U-shaped, and the mandible is thin and light. The incisors are broad and flat, while the molars have low, rounded cusps with thick enamel. They have large, dagger-like canines in both the upper and lower jaw. This dangerous dentition helps them adapt to their environment by being able to protect themselves from predators who hunt them.

Chimpanzee

  

Chimpanzees live in a wide variety of habitats, including tropical rain forests, woodlands, swamp forests, and grasslands in western Africa. Chimpanzees are omnivores, foraging for food in the forests during the day, eating leaves, fruit, seeds, tree bark, plant bulbs, tender plant shoots, and flowers. They also eat termites, ants, and small animals such as young monkeys. Their dentition is larger. They are omnivores but eat fruits and vegetables regularly. They also feed on insects including termites. Because chimpanzees eat animals and vegetation, it is necessary to have both sharper teeth in order to tear meat and flatter teeth in order to chew their food.

I have learned that the environment has so much to do with the way these animals look physically and behave mentally. During my research, I have found that many primates who live in an area where they mainly feed off of fruit, vegetables and flowers, start losing their canine teeth over time because they no longer need them. They also behave different when they are physically different. When a primate has sharp canine teeth, they are eager to hunt prey or defend themselves against predators. Animals without them tend to create their habitat in safer areas such as on higher ground or in trees where food is readily available without having to be put in danger.

Analogy & Homology

The butterfly and the moth

A. A butterfly is an insect that tends to fly during the day from the order Lepidoptera, the butterflies and moths. The butterfly's life cycle consists of four parts, egg, larva, pupa and adult. Butterflies have large, often brightly colored wings with fluttering flight.

A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Most moths are nocturnal with 150,000 to 250,000 different types of species, thousands still not found yet.

B. The homologous trait is the antenna that both butterflies and moths possess. With butterflies the antenna are clubbed while in moths they are tapered. In some species of moths the antenna are enlarged into feathered organs. There are differences between this homologous trait because moths are night insects which makes it harder to seek a mate, They are not able to see well so instead males have antenna that make them more capable to seek by smell, picking up pheromones produced by females.

C. The common ancestor of these two species has not yet been determined. It has been studied that by 40 million years ago, butterfly and moth families were already in existence. However, there is a theory that butterflies and moths originated within a crustacean group that includes water fleas and fairy shrimp around 400 million years ago. Even though it is not easy to determine the common ancestor of butterflies and moths, it is easy to assume that the common ancestor possessed this trait because without it they would not be able to sense in order to survive and evolve whether it is to find a mate in order to reproduce or determine where their food is.

The tortoise and the hedgehog

A. The tortoise comes from the family of reptiles. They use their shells to shield themselves from predators, containing an endoskeleton and an exoskeleton. They tend to be reclusive even though they are not nocturnal.

The hedgehog comes from the subfamily Erinaceinae. They are nocturnal animals, known to have been recognized by their spines which are actually hollowed hairs made to be stiff with keratin. Their “spikes” are not poisonous, but cannot be easily removed.

B. Both tortoises and hedgehogs share the analogous trait to draw into themselves when they feel threatened. The hedgehog curls into a ball protecting its vulnerable parts with its outer spines, and the tortoise retracts its vulnerables such as its head, tail and feet into its protective shell made of bone. The hedgehog uses its spines to protect the most precious parts of its body while the tortoise uses its shell. Both species have developed protective features on their bodies in order to keep predators away and protect themselves from danger.

C. Hedgehogs are mammals and tortoises are reptiles. They are very distantly related so it is likely that these two species would not have inherited their behavior of withdrawing themselves from danger from a shared ancestor.

Protein Synthesis

I hope I did this right!

UCCGTACCAAGGGAACGCAAGCCCCAGTCTGTTAATCACCA

Historical Influences on Darwin

There are many people who influenced Charles Darwin’s hypothesis, but I believe that one scientist in particular contributed the most to Darwin’s work. Charles Lyell was a geologist and was known to be “obsessed with the implications of the evolutionary theory. Not only was Charles Lyell “one of the first prominent scientists to support The Origin of Species,” but he was also a close friend of Darwin’s. Just by being friends with him, I feel that Lyell had such a great influence on Charles Darwin because they worked together frequently. They enjoyed each other’s company and debates about the theory of evolution. Charles Lyell lent a book that he wrote to Darwin called Principles of Geology while on the HMS Beagle in order to give him an idea of his own theory on the process of evolution. This trip is now famous because it is known that Darwin created his theory of natural selection while on this trip. Lyell’s theory in his book explains how new species would appear as older ones became extinct, one species could not evolve into another over time. Although this is quite the opposite of what Darwin proposed later on, I believe that Lyell’s opinion had a huge effect on Darwin’s thoughts because after reading this book, Darwin came up with his own theory of natural selection. This is the point of Darwin’s work that was greatly affected by Charles Lyell. Darwin was able to realize the flaws in Charles Lyell’s hypothesis and create his own as well as convince Lyell that his idea was much more practical and even managed to change Lyell’s beliefs completely. I do not think that Darwin would have been able to develop his theories of natural selection without the help of Charles Lyell. I feel that his theory of natural selection was able to be fathomed because he read Lyell’s book and without it, would not have had the idea of natural selection in his mind. The attitude of the church, which was an obvious amount of anger and disapproval, seemed to have a positive effect on the eventual publication of Charles Darwin’s book The Origin of Species. There were protests and negative public statements, but the book was repeatedly sold out. It seems to me that all of the unintended publicity that the church was giving to Darwin helped him raise awareness about his book and hypothesis.

Sources:

http://www.victorianweb.org/science/lyell.html

http://www.lycos.com/info/charles-lyell--charles-darwin.html