Week 8: Human Variation

1) Cold: Environments that are cold negatively impact homeostasis by putting more pressures on a human's body to survive. If a person is in an excessively cold environment for too long, unprotected, he/she can die from exposure, suffer from frostbite, or contract hypothermia. All of these conditions negatively impact a human's survivability and disturb homeostasis.

2) Short term: One short-term adaptation to the stress of the cold is one that any reader can recall for themselves: shivering. In order to increase body heat and keep a person active, we start to shiver as a reaction to the cold. Shivering is the exact opposite of sweating, with the benefit being to warm up a person.

Facultative: One facultative adaptation to the cold is vasoconstriction, which is the narrowing of blood vessels as a response to a cold environment in order to retain body heat.

Developmental: One developmental adaptation to the cold, specifically exhibited in Mongolian people is having short appendages, which creates a smaller body area and makes it easier to retain heat.

Cultural: One cultural adaptation to the cold, again exemplified by the Mongolian people, is a nomadic lifestyle. Specifically, herders migrate along with their herds of livestock (horses, sheep, goats) across Mongolia to less extreme (in regard to the cold) locales so their herds can graze and do not freeze to death. Also, the people themselves are not tied down to a specific environment, so they can retreat from the advancing cold to a degree.

3) The benefits to studying humanity in regard to clines rather than other classifications are that they are less biased to the organizer's beliefs, more accurate, more holistic, and give a wider view to humanity that can be seen as a spectrum of adaptations for specific niches. The information we gather from these kinds of explorations is helpful because it paints an accurate portrayal of human evolution and adaptation, rather than lumping people into categories over trivial distinctions, such as race. This information can be used in a productive way by anthropologists to aid other groups of people who fall under the same niche. Adaptations one group has developed may be applicable to another group.

4) Race is not a strong enough breakdown/organizational system to explain the adaptations I expounded on in question #2. These adaptations aren't race specific, they are environment specific. Race is a weak organizational system for characterizing the human race. The adaption perspective is much more holistic and unbiased, focused rather on what is actually the case rather than socio-political organization based on power and privilege.

Weeks 6 & 7: Language

Part 1:
A) I found this experiment to be very difficult. To give some context to my conversation, I tried explaining what I did for my birthday, the 24th, to a friend. Trying to explain that I watched a movie and ate out with friends is quite difficult without the ability to use a symbolic language.
B) My partner found the experiment amusing and altered his communication with me after only about a minute and a half of attempting normal conversation. The conversation evolved into an elaborate game of charades, with me doing quite a poor job. My partner spent most of the time trying to guess what I was trying to say rather than take part in a two-way conversation.
C) The culture that has the ability to use a symbolic language (and be understood by the culture that cannot use that type of language) definitely has the advantage in communicating complex ideas. The speaking culture could deem that the non-speaking culture is primitive or savage from their lack of a spoken language. People with speech impediments, mental disabilities, who are deaf or mute all have trouble communicating with spoken language. People generally try to simplify their ideas, speak louder, or speak slower when communicating with people who have trouble with spoken language. This barrier creates great difficulty for the non-speakers because they are inhabiting a world where spoken language is almost a necessity in day-to-day life.
Part 2:
A) To be honest, I had a few vocal intonation and head movement slips in the 15 minute period, so it was impossible for me to spend that amount of time without the aid of non-spoken language cues. The experiment was made difficult because, from my experience with the experiment, it's very hard to communicate without the aid of non-spoken language. Communication is more than just words coming out of your mouth and not being able to use non-spoken aspects of language was very difficult for me in the 15 minute period.
B) My partner, the same one I used for Part 1, made a comment that I feel is important, which was that he became bored during the conversation. He said without other parts of communication, it was hard to pay too much attention and the conversation ended up being monotonous and unexciting.
C) I feel that non-speech language techniques are essential to communication. Intonation, pointing, head movements, and gestures all put another dimension on communication. Language sets the foundation, with all the non-language aspects building upon it and making communication that much easier.
D) People who have Pragmatic language impairment (PLI) have, among a list of other characteristics, difficulty reading body language. One adaptive benefit, which may not be accesible to people with PLI is the ability to read another's mood or intentions without the need of being explicitly told. For example, a child who can see that a parent is angry by their facial expression can deduce that it would be a bad time to ask to go out for ice cream. When trying to consider an environmental conditions in which it would be beneficial to not read body language, nothing came to mind. Body language seems integral to any type of human communication; if it wasn't integral to communication, it wouldn't have developed the way it has over our history as a species.

Week 5: Piltdown Hoax

     On December 18th, 1912, the duo of Sir Arthur Smith Woodward and Charles Dawson presented Piltdown Man, nicknamed "the earliest Englishman," to the world. The remains of this Piltdown man were a skull and jaw fragment, fossilized and said to be the earliest link on the evolutionary chain to man. In the years that the Piltdown discoveries were accepted as fact, man scientists based their careers on these discoveries and the world itself accepted the British discovery that man arose in Britain. The credibility and standards of the Natural History Museum of London, along with the post of Sir Arthur Smith Woodward as part of the Natural History Museum, these discoveries were accepted at face value, even though the evidence didn't necessarily add up. Well, in 1953, thanks to the dutiful work of Kenneth Oakley and his chemical testing, it was proven that the Piltdown items, all of them, were forgeries. In other words, it was all a big hoax that had fooled the scientific community for over 40 years. The discovery of this hoax occurred through Oakley's chemical testing, which was testing for the items' nitrogen content, which didn't coincide with the estimated dates. Upon further investigation, the skull was discovered to have been an orangutan's jaw that had been filed, boiled, and stained in order to appear older than it really was and more human. All of these discoveries were proven false, rocking the foundations and credibility of London's Natural History Museum. The question of science's credibility came to the public's mind. How can the public trust that what these scientists say or discover are truthful or honest?

     Human nature dictates that human beings are imperfect and bring biases to all their endeavors. Sadly, even the quest for scientific truth can be lead astray by human faults. The nationalism that infested the world during the buildup to the first world war was a primary cause for this hoax. Britain, as a nation and identity for its people, needed to be as good or better than the rest of Europe, especially when it came to human origins. What could be better than to say that the human race rose within your borders and spread to conquer the world? Even better, the first man was English. Well, this put the country into the perfect state for a hoax such as the Piltdown Man to occur. Richard Dawson seemed to be an egomaniac in the sense that he seemed to be obsessed with garnishing more academic credibility as an amateur scientist. As an amateur, he was unqualified to truly say that what he discovered was what he said he had discovered. He was consistently stretching his knowledge and the truth in order to make a name for himself. Woodward's unwavering and adamant support for the Piltdown Man was also unbecoming for a scientist. As the pre-eminent person in his field, it was his duty to be as critical of the discovery as possible, especially before accepted it as fact. However, the spotlight placed on Woodward and the worldwide fame and recognition went to his head, turning him into a celebrity rather than a scientist.

     In my opinion, the "human" factor cannot be completely removed, but it can be severely limited. Rather than make national ventures into scientific inquiry, we should push for more international scientific work. With the collection of resources of multiple, if not every nation, our possibility for scientific discovery will become almost endless. Also, having unrelated, both in regards to family and nation, investigations into discoveries will keep people from accepting hoaxes for outside agendas. Science and scientific discovery should be based on a quest for the truth and an effort to actively understand the universe and make it a better place for all, including humankind. If it were possible to remove the human factor from science, it would be a grand mistake to do so. Even with all these costs and faults that humans bring to the table, human curiosity is also the driving force in science. Without one, we can't have the other, but that doesn't mean that we can't do our best to limit the negative factors humans bring to scientific inquiry.

     Personally, I have a new-found skepticism when it comes to science. Scientists are not above deceit for their own personal gains, like the rest of humanity. They are neither the best of us, nor the worst. However, just because people have the ability to lie, that doesn't mean they will do so. Everything should be seen from a skeptic viewpoint until it can be verified and proven by multiple means. That's the life lesson to take away from this hoax. Don't believe something until they can prove it is true, rather than someone just telling you that it is true. Proof is necessary to be accepted as truth, without proof, there is no certainty.

Week 4:Comparative Primate Biology Post

Body type and sexual Dimorphism:
1) Lemurs (Prosimians/Strepsirhini)
a) Lemurs are native only to Madagascar and the neighboring Comoro Islands. Most lemurs live in trees and spend the majority of their time at the top of the rainforest or in the forest mid-level. The exception to this are ring-tail lemurs, who spend the majority of their time on the ground. The environmental distribution of the lemurs extends from the lush, wet rainforests of eastern Madagascar to the southwestern dry desert.
b) Lemurs vary greatly in body size by specie, from weighing only an ounce to weighing 15 pounds. Most lemurs exhibit sexual dimorphism in regard to having different coloring between males and females.
c) The varying body sizes are linked to the environment in regard to where they are located. Smaller bodies are adapted more readily to living on the tree tops where branches are thin and fragile, not being able to accommodate large amounts of weight. The sexual dimorphism exhibited by lemurs is also based on the environment and social patterns. With lemurs being spread out not only over areas but also different heights, it becomes an issue to readily distinguish males from females without sexual dimorphism.
d)

2) Spider Monkey (New World Monkey/Platyrrhini)

a) Spider Monkeys live in the tropical rainforests of Central and South America, ranging as far north as Mexico. These primates spend their lives living in the trees, using their tails and thumb-less hands to powerfully grip branches from tree to tree. These animals live in groups and spend most of the day in groups as large as two to three dozen animals.

b) In regard to Spider Monkeys, sexual dimorphism is non-existent while differences in body size between males and females aren't that distinguishable.

c) Living entirely in trees and spending the majority of their time in groups, there is no real advantage to differences in body sizes or sexual dimorphism in spider monkeys. Smaller bodies are more useful for navigating trees and with constant grouping, there is no readily available need to distinguish males from females.

d)

3) Baboon (Old World Monkey/Cercopithecidae)

a) Baboons live in Africa and Arabia, with five different species. Baboons seem to prefer savanna and other semi-arid environments in Africa and Arabia, but they can also be found in tropical rainforests. Baboons, unlike the other primates mentioned, are terrestrial and spend most of their time on the ground.

b) The body size of baboons can range from 30 pounds and 20 inches all the way to 90 pounds and 47 inches. Sexual dimorphism is expressed in baboons with males generally being larger, males of the Hamadryas species have a white mane, and some species of males have more developed canines.

c) The sexual dimorphism and body size differences stems from the terrestrial environment of the baboons. To readily defend from predators, males are larger and have more developed canines. Baboons don't have the option of climbing to the tree tops to escape from predation.

d)

4) Gibbon (Lesser ape/Hylobatidae)

a) There are 15 species of Gibbon ranging from India to China to Borneo, living in subtropical and tropical rainforests. Gibbons spend the majority of their time in the canopy, hardly ever coming ground-side.

b) Gibbons range in body size from the largest, siamangs, growing to 29 pounds and smaller species only growing to nine pounds. Gibbons exhibit little sexual dimorphism, with body sizes between male and female being fairly similar and only siamangs showing different coloration between gender.

c) The reason for low amounts of sexual dimorphism again extends from the environment. Living in the tree tops, there is no advantage for one gender to be bigger than the other. Behaviorally, in regard to gibbons being monogamous and mating for life, there is no need to distinguish males from females for breeding purposes, because a gibbon keeps the same partner for life.

d)

5) Chimpanzee (Great ape/Hominidae)

a) Chimpanzees inhabit African rainforests, woodlands, and grasslands. Chimpanzees live in both tree and terrestrial environments, being adapted to both in regard to their long arms and shorter, powerful legs.

b) The sexual dimorphism exhibited by chimps is similar to that in humans: males are larger than females. Males tend to be both taller and heavier than their female counterparts, Males on average weigh 43kg, while females weigh 34kg.

c) The sexual dimorphism exhibited in chimpanzees stems from their part terrestrial living arrangement. The larger males are more adapted to defend the group of chimpanzees in terms of an attack by a predator or group of predators.

d)

Summary:

The environment, in regard to both differences in body size and sexual dimorphism, is the decider on whether those two traits will be exhibited. For all the primates discussed who were mostly tree-dwellers, differences in body sizes and sexual dimorphism was not beneficial to the species, so they weren't traits that were developed. For the primates who were terrestrial or partly terrestrial, these two traits were beneficial in regard to protection from predators. Trees seem to serve as natural barriers against predators, so the primates that didn't have these natural barriers had to develop a trait themselves to offer protection, which in turn is sexual dimorphism, specifically through different body sizes between males and females.

Week 3: Analogy/Homology

1) Homologous trait: Echolocation in regard to sperm and killer whales
A) The two species that possess echolocation are sperm whales and killer whales, which are both Odontocetes, or toothed whales. Both whales' habitats are distributed throughout all oceans.
B) In all Odontocetes, echolocation is achieved through the passing of air through the phonic lips, which create clicks in the direction the whale's head is facing. The sounds themselves are focused in a whale's melon, which is part of the nasal apparatus. The sounds, or clicks, are then bounced back and heard within the whale's inner ear. In regard to killer whales, echolocation is used for both hunting and communication. Because killer whales do not hunt in excessively deep waters, the wavelengths used for creating their clicks are not very low and their range of hearing in regard to echolocation matches the sounds they produce. In regard to sperm whales, because they hunt under the photic zone (where light can penetrate), they use much lower frequencies when echolocating.
C) The common ancestor of these two species was a toothed whale that had developed echolocation. This is known because all Odontocetes possess echolocation, which is attributed to a common ancestor who had evolved this trait for hunting.
D)

2) Analogous trait: Echolocation in killer whales and microbats

A) The marine mammals known as killer whales, which possess the trait of echolocation, are Odontocetes. Microbats are a suborder within bats, which are flying mammals, and are known for their ability to use echolocation. The Australian ghost bat, which is carnivorous and hunts large insects, lizards, frogs, birds, and other bats is the particular microbat that I will focus on.

B) Both killer whales and Australian ghost bats use echolocation as a hunting tool. In Australian ghost bats, they emit high pitched sounds through using their vocal chords and once the sound has bounced off an object, it returns and is heard through the bat's ears. The bat is able to identify how big the object is by the intensity of the echo and it's direction by which ear the sound returned to. The killer whale produces a click through the passing of air through it's phonic lips and picks up the sound once it bounces back through it's inner ear. Killer whales also use forms of these clicks to communicate over long distances.

C) Both species are mammals, but whales are marine mammals while bats are flying, land-based mammals. The common ancestor to both species was indeed a mammal, but the common ancestor is so far back in both species' histories that it was before the development of echolocation. Therefore, echolocation is a case of parallel evolution.

D)

Week 2: Protein Synthesis

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Week 1: Historical Influences on Darwin

1) Jean-Baptiste Lamarck:
Lamarck had the most positive influence over Charles Darwin's theory of Natural Selection in two major ways. Firstly, he was the first person to suggest that a dynamic relationship between species and the environment existed. Secondly, during Darwin's schooling years at Edinburgh, the professors Darwin studied under were outspoken supporters of Lamarck and his theories.
2) Lamarck's major accomplishment in the realm of science was his theory of evolution through the mechanism of inherited acquired traits. Lamarck stated that the external environment directly changed an animal's activity patterns. The change in the species would occur through the use/disuse of body parts and the parts themselves would change or be lost to fit bodily needs.
3) Organisms with better access to resources will be more successful in their reproductive efforts:
The giraffe example of Lamarck's theory supports this particular point. The giraffes who stretch their necks have better access to the leaves and then this acquired trait will be passed on to the giraffe's offspring. As known today, this theory is wrong because the only traits that can be passed genetically are inheritable traits, not acquired ones.
In order for traits to evolve and change, they MUST be heritable:
According to Lamarck's theory, the longer necks acquired by giraffes were inheritable traits that could be passed to their offspring. Again, like the previous point, acquired traits are not inheritable.
Individuals do not evolve. Populations do:
In Lamarck's theory, individual giraffes develop longer necks and then pass this trait off to their offspring. Unlike Darwin's theory, this theory can be interpreted as stating that individuals evolve and then pass of the trait to their offspring.
4) No, Darwin would never have developed his theory without the groundwork laid by Lamarck. Darwin's outlook was highly influenced by Lamarck's theories during his university years, and it can be assumed that his academic interests would not have been developed the same way without Lamarck. Also, Lamarck's theories laid the groundwork for Darwin's theory of Natural Selection, which built off of Lamarck's previous work, eventually superseding it.
5) The attitude of the Church made Darwin cautious about publishing his "On the Origin of Species." Darwin literally waited until the last possible moment to publish his findings and theory, in fear that Wallace would get credit for the theory. The Church's negative outlook on evolution could be stemmed to the first evolutionary theorists being anti-Christian and atheist. They tainted the topic for future newcomers, and Darwin, being part of the established order, had much to lose from publishing something that went against Church teachings.
http://www.ucmp.berkeley.edu/history/lamarck.html