Chapter+11

Place your questions and answers for Chapter 11 here. A: A hiccup is a reflex which is a stereotyped twitch involving many muscles in our body wall, diaphragm, neck, and throat. We acquired the hiccup, specifically, from amphibians. Hiccups are controlled by a central pattern generator, and the pattern generator that is responsible for hiccups is identical to one in amphibians (tadpoles). Tadpoles use this generator when they breathe with gills, so they pump water into their mouth and across the gills, but they don't want the water to go into the lungs, so they close the glottis, which is just an extended form of a hiccup. This supports that all life has a signature descent with modification because we have the same central pattern generator as one in amphibians, however, the result of this pattern is a hiccup in humans instead of just helping the organism breathe like an amphibian uses the pattern generator for. (J. terHorst)
 * Q: What are hiccups and how did we acquire them? How does this example further support that all life has a signature descent with modification? (T Gebhart)**

A: Descent with modification refers to the idea that as a species goes through generation after generation, subsequent offspring will vary from their predecessors, and the changing of a population is continuous over time. Darwin looked at this in his study of finches on the Galapagos Islands. He was able to examine how their were variations in the shape and size of the finches' beaks across the islands, and he attributed this variation to differences in dietary necessities caused by different floral populations in the birds' habitats. (P. Oakes)
 * Q: Organisms are classified and organized by binomial nomenclature through the study of taxonomy. Shubin uses the phrase "descent with modification." What does he mean by this? What organism did Darwin study that deals with "descent with modification" and what did Darwin look at? How did these modifications help the organism? (J. Speelman)**

A: Natural selection and evolution that has been demonstrated through our lineage, especially through the //Tiktaalik//, demonstrates adaptation based on environment. I believe that technology will take the role of environmental factors when shaping new generations based on the introduction of cutting age technology in regards to medicine and reproduction. Unfortunately, the people with the most access to the technology that is shaping our future is the wealthier class, due to the high cost of this technology and treatment. Technology and new techniques are preventing defective or problematic births, and this generation of 'perfect' children will be favored in natural selection and will be seen in the evolution of our species in the future. A side effect of this new evolution may have immense social and political ramifications as humans become more polarized in their health based on class. (M. Blanchard)
 * Q: Shubin explains our incomprehensible lineage, and questions how far back our lineage actually goes. This lineage is essentially evolution, made possible with the help of natural selection and mutations. How do you think the technological advancements in the world today will affect natural selection (and evolution) in the future? (L. Bercz)**

A: The thrifty genome encourages humans to always want and crave sweet and fatty foods, even if we're no hungry. The thrifty gene allows us to save resources (fat deposits) in case of famine or malnourishment. It was advantageous for ancient humans because they were hunters and gathers and went through cycles of feast and famine. They might not know when they will find their next meal and the thrift gene tells me them to eat all fatty and sweet things they can. Fortunately today, we have supermarkets full of food 24/7. However, in today's environment, our thrifty genes cause overeating and diseases like diabetes, obesity, and heart disease. One maladaptation that the book points out is sleep apnea and snoring caused by our ability to talk (C.Nikolai).
 * Q: Many human diseases and ailments are due, at least in part, to adaptations that make us the way we are. One of these adaptations is called the 'thrifty gene'. What does this gene do in humans? Why would it be advantageous in proto or early humans, and why is not today? What other maladaptations can you think of? (M. Purdon)**

A: There are many odd adaptations that have caused the human body to evolve into what it is presently. For example, humans walk upright and are able to grab objects. For bipedal walking, the physical symptoms are a shock-absorbing, curved lower back, strong knees, and leg support. For grabbing objects, humans physically have opposable thumbs. Moreover, modern living, specifically the modern human's diet, has had a generally negative impact on the health of humanity because of the lack of some nutrients and the surplus of others. Historically, humans are not meant to eat the heavily processed foods as humanity does, and such eating habits have cause a rise in cardiovascular diseases and more. (T. Russell)
 * Q. What odd adaptations have our bodies had to undergo in order to make us the way we are? What are the physical symptoms of these oddities? And finally what impact is modern living making on human bodies and why is that part of our biology according to history? (E.Olson)**

A: The mitochondria is a vital part of the cell. It is the location of several metabolic pathways that occur in order to produce usable energy from just oxygen and sugars, such a glucose. When something is then wrong with an organism's mitochondria, the organism cannot produce enough energy in an efficient manner in order for the cell to work properly. This causes great problems when multiple cells are experiencing this same issue. This results in an issue with the tissue or possibly the entire organ. Shubin says the bacteria //Paracoccus denitrificans// is one that is very useful in studying mitochondrial diseases due to its genetic similarity with mitochondrion. These two are so similar due to the theory that eukaryotic cells evolved from one prokaryotic cell engulfing another. What likely happened is one prokaryotic cell engulfed the bacteria that Shubin described, and found that the effects were highly beneficial. This cell continued to reproduce, passing on this new structure inside of it, until what was once a separate bacterium became an organelle within the cell. (L. Bentley)
 * Q: In the book, it talks about mitochondrial diseases. Why are mitochondrial diseases so harmful, and what type of bacteria does Shubin say is especially useful for studying mitochondrial diseases? Finally, using what we learned earlier in the year, why are bacteria and mitochondria so similar? (A. Nolan)**

A: The two disorders that Shubin mentions are sleep apnea and choking. With sleep apnea, while someone is asleep, their muscles in their throat will relax. Most of the time nothing happens, but for some the passage will collapse, leading to long stretches of time without a breath which can be fatal. Choking occurs due to the fact that the mouth leads to the trachea and the esophagus. We use the same tube to eat, breathe, swallow, and talk, which lends to a problem when a piece of food gets lodges in the trachea instead of going down the esophagus. Nonetheless, the ability to talk has been a huge key to evolutionary success. Talking has allowed humans to communicate and with communication comes collaboration and growth and development. Humans would never have been able to become so advanced if not for talking and therefore would probably not be at the top of the food chain today. (R. Heis)
 * Q: Throughout this chapter, Shubin mentions several sicknesses that have resulted through adaptations that have made mammals who they are. More specifically, he touches on the "steep price" that comes with talking. Using evidence from this chapter, clearly Identify and explain in detail the two disorders that Shubin mentions. Along with this, there are many risks that come with being able to talk, however, do you think this ability has been essential to evolutionary success? Why or why not. (O. Heltman)**

A: This is an example of something that could change in future generations, because where gonads are located compared to sharks is quite different, sharks gonads are located around their upper chest behind their liver while humans are not. the tendency does not decrease the survival of organisms because it is not life threatening. so It will never be phased out by death, unless a direction shift is forced to cause change i do not believe there is a reason that this would change, I believe that adaptation overtime would affect a species potentially causing the species to change completely because if they are adapting over time it can be said they are changing over time as well. (T. McDaniel)
 * Q: In this chapter, Shubin describes how the presence and location of gonads and the subsequent weakness in the body wall of primarily males causes a tendency for hernias to develop in males.** **As we have already seen through processes of evolution, adaptation, and advantageous mutations in the past, is this an example of something that could evolve/change in future generations? Does this tendency truly decrease the survival of these organisms, and would an adaptation over time affect the species drastically? (M.McKinney)**


 * Q: What are some of the "costs" of speaking that Shubin mentions towards the end of this chapter? Explain why, in context to evolution, why benificial mutations can come with negative negative side effects. (E. Bach)**

A: Some of the "costs" to speaking are choking and sleep apnea. Sometimes, negative side effects come with beneficial mutations for several reasons. The first primary reason is due to our evolution as human beings. Our similarityto fish and tadpoles has hindered us to become truly independent animals, and therefore, we share some traits with these other organisms. Another reason is due to the fact that our environment is constantly changing and sometimes our "beneficial" mutations, are not always 100% ideal. (H. Schwarz)

A: Evolution is similar to Shubin's example of bozos because both show how differences in a species appear over time and how organisms mutate and develop unique characteristics. In the bozo example, an "original humorless couple" with no distinctive characteristics had great-great grandchildren who had all of the bozo characteristics, such as curly hair, floppy feet, and a squeaky nose. Similarly, the single-celled organisms billions of years led to the development of humans. However, we are all related with similar characteristics. We maintain the traits that are necessary for survival and without them, we would not be able to survive. (N. Sarkar)
 * Q: In this chapter, Shubin once again returns to the Russian doll set analogy. Explain in your own words how evolution, such as the bozo or polar bear/turtle evolution, is similar to a set of Russian dolls. What makes the patterns of relatedness so important? Could humankind exist without it? (C. Sanders)**

A: Some reasons why morphing a fish into a human is prone to error because, any of the given advantages that come with adaptation, can also lead to many negative side effects. For example, the adaptation of speach has some pros and cons. The main pro is that it allows humans to comunicate with one another. However as seen in this chapter of your innerfish, it comes with some down falls such as the issue of having a wider and more complex throat and allowing us to be more prone to choking. (E. Bach) A: Humans evolved over millions of years in order to be the fittest, to swim across oceans, wade through streams, and trek through the Savannah, however, these environments are no longer the typical way of human life and although evolution has gotten us this far, it hasn't quite caught up with us yet. Living to 100 years old, sitting in the office all day, and eating fast food isn't the ideal of the human body, and it has caused problems in humans. Other examples of key differences between us and fish is that humans are bipedal animals that have a very different center of gravity. We no longer enjoy the weightlessness of water as life on land puts great stress on joints, which wear down faster than our lifetimes. Also, adaptations such as speaking has lead to the occurrence of things as little as hiccuping to complications such as sleep apnea and choking. Though human evolution has created a robust species, it also has many downfalls. Though our many new evolutions has led to much good, such as walking, speaking, thinking, and being an apex predator, it all comes at a price. (I. Perler)
 * Q: One part of this "summary" chapter talks about how we have evolved, and how even with the principle of survival of the fittest, we are prone to shortcomings like disease or hemorrhoids. give some examples as to why, in Shubin's words, "Morphing a fish into a human" is prone to error.(C.King)**

A: These animals are known as Tetrapod mammals. The anatomical structure they have is a //Three-boned middle ear//. This anatomical structure has three bones or Ossicles that detect the vibration in the Tympani cavity and send them to the fluid membrane of the inner to be processed as a sound. (C. Hurst)
 * Q: The subset of multicellular animals which Shubin describes as having "a body plan like ours, with a front and a back, a top and a bottom, and a left and a right, that have skulls, and that have hands and feet" that are known as mammals, also have what anatomical structure? Briefly explain the the anatomy of this structure and how it functions. (N. Braun)**