The Argument: One of a Kind
The crux of the argument for the entire book is that we have control over our genius. Even our own genetic code can be altered and changed by the environment and lifestyle we choose to live in. (pg. 163) Even small mice can manipulate their fur color by simply changing their diet. (pg. 159) It seems like choice have a bigger dictate over our lives than natural selection. That is what this whole book has been about, proving to us that our destiny has not been predetermine, instead we have the ability to shape the raw talent within us to become something greater through lifestyle changes with biological evidence such as epigenomes.
What question that really is begging to be asked is what makes us, humans so special? Choice in changing our destiny seemed to always put us apart from animals but with discovery of epigenomes that kind of changes that perspective. What differentiates us from other animals, when their choices can affect their success and failure in life as well? Or are we more closely related to our primate friends than we believe to be?
Ellen Zhou (ellenzhou2006@gmail.com)
Humans, from a molecular perspective, are truly nothing special at all in the animal kingdom. The discoveries made in the field of epigenetics are universal. Histone acetylation and DNA methylation both control gene expression in all eukaryotes, so humans are by no means unique in this respect.
ReplyDeleteHowever, what makes the human situation unique is the degree to which we can control our own choices, and subsequently our epigenetic expression and inheritance. Humans do indeed possess innate instincts and fixed action patterns from birth. However, humans, along with other more developed animals, can modify these responses with learning based on previous experiences, and can use the highly complex technique of cognition to approach different situations with awareness, reasoning, recollection, and judgement (Campbell 1128).
The real distinction between humans other animals, even compared to the closely related primates, is the development of an advanced language that allows the communication of abstract ideas and concepts to others. Epigenetic inheritance for most other animals is largely unaffected by individual decisions, rather they are affected by variable environmental conditions. However, humans are unique in that they can make choices influenced by others through language, as well as cognition to override innate behavior, which will have a direct effect on the epigenome.
Now, it is important to make a distinction between communication and language. Communication is in fact extremely common, and birds, insects, reptiles, and mammals almost all have their own form. However, human language is unique in that it is stimulus independent – meaning that the subject of communication is not necessarily tied to some real-world event (http://sciencenetlinks.com/science-news/science-updates/human-language/). This is what allows humans to make new decisions that they might not necessarily have seen before, and allows for the much greater effect of the epigenome on human inheritance, especially considering most modern humans live in a very homogeneous environment.
This degree of control over our own epigenome means that we have a responsibility to use our intelligence to benefit our children. Shenk introduces a novel concept in biology – that “lifestyle can alter heredity” (161). Though other animals certainly experience the same epigenetic inheritance as we do, they lack the mental facility and complex communication that allows them to override instinct and make decisions.
David Whisler (dwhis428@gmail.com)
As mentioned previously above the DNA of a human does not have anything more special to it than the DNA of another animal. The structure of the DNA is the same in all the animals. The attention should be brought towards the actual information stored in the DNA of a human. The easiest way to compare humans to animals is to use chimpanzees as a comparison because they are humans closest relatives. Even a child can see the similarities in appearances between a human and a chimp. But there are a great number of differences like the walk and the intelligence level between the two. There is only a four percent difference in the genome of a human and a chimpanzee (http://anthro.palomar.edu/primate/prim_8.htm). The small difference therefore strongly affects the differences between the two living beings.
ReplyDeleteThe difference could be seen in the HAR1F regulator gene which is associated with the creation of brain tissue during early development before the 19th week (http://anthro.palomar.edu/primate/prim_8.htm). A difference in the makeup of the brain tissue contributes to a larger cerebral cortex. The cerebral cortex contains the part of the brain that contribute to the ability of speech and reading (Campbell 1075). A human baby is born to learn and develop to become intelligent because of the natural biological size of the brain. This might be one of the reasons why humans have the ability to think at a higher level and make choices.
This could be seen in a way how humans are different from animals because of the behavior. The ability to choose and go against natural instincts is one of the ways humans are special. Think about a time when you were extremely hungry and wanted to eat and the only thing preventing you from eating the candy in your backpack was the fact that you were in class. This ability to make decisions and give values to actions makes us different from all the animals. By having the ability to go against natural instincts humans can achieve great things because we comprehend that natural instincts are sometimes unnecessary depending on a situation. Look at human babies and their various accomplishments in the first year of life. Biologically their brain is made to learn everything by “changing their minds” (Shenk 131).
Another way to look at a population of humans and compare to a population of animals. Humans create laws and rules that ideally keep everyone safe in a society and promote a civilized place. On the other hand animals that live in a population follow certain behaviors that are shown through actions of the animals. In wolf packs the strongest male will control the pack during hunting and traveling. But humans can understand that strength is not the most important characteristic of being a leader, instead a leader is chosen for his ability and knowledge to lead.
Ayana Dambaeva (adambaeva@gmail.com)