Meat Eating Accelerated Face Evolution

Recent studies have found that the eating of raw meat and the making of stone arrows contributes to the smaller faces and teeth of the ancient relatives. Meat and tools, not the advent of cooking, was the trigger that freed early humans to develop a smaller chewing apparatus. This change could have allowed for other changes such as improved speech or even shifts in the brain size. Cooking meat became common much later in time. The earliest members of our genus, Homo, are only sparsely represented in the fossil record. And when the Homo Erectus specie appeared two million years ago humans had bigger heads and bodies contributing to more energy requirements. A reason for these changes, cooking, does not make sense any more. Since was only common around 500,00 years ago so it couldn’t have much of an effect. Prof Lieberman explained that, "At some point in human evolution, there was a shift - we started to eat less. This shift is made possible by two factors: we eat a much higher quality diet than our ancestors, but we also eat food that has been heavily processed." The scientists evaluated chewing performance by feeding adult experimental subjects samples of meat, and the kind of vegetables our early ancestors might have consumed before incorporating meat into their diets. They measure how much was chewed and how much effort it took to chew it. broken up before swallowing.

The findings suggest that by eating a diet of one-third meat, and using stone tools to process the food - slicing the meat and pounding the plant material - early humans would have needed to chew 17% less often and 26% less forcefully. This shows how much humans have changed over time. We leave in a world where food is heavily processed, so we don’t use as much effort as we used too.

I thought that this was a very interesting article that made me think a lot about the way I eat. It also allowed me to imagine the way people used to eat. I think the only thing they could fix would to add more relevance to the article. But other than that I thought the article was clear and interesting.

"Meat Eating Accelerated Face Evolution - BBC News." BBC News. N.p., n.d. Web. 09 Mar. 2016.

In DNA, Clues to the Cheetah’s Speed and Hurdles

Moffet, Barbara S. "In DNA, Clues to the Cheetah’s Speed and Hurdles." The New York Times. The New York Times, 26 Feb. 2016. Web. 29 Feb. 2016.

http://www.nytimes.com/2016/03/01/science/in-dna-clues-to-the-cheetahs-speed-and-hurdles.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science&region=rank&module=package&version=highlights&contentPlacement=2&pgtype=sectionfront&_r=0

Chewbaaka the cheetah’s genetic information in combination with that of other cheetah’s has led to the complete genome sequence of the cheetahs, giving scientists a better understanding of their traits and how they were acquired. Cheetahs originated in North America, along with the related puma. They then migrated across the bering strait around 10,000 years ago into Asia, and then Africa, to where they are found today in Southern and Eastern Africa. These migrations caused a bottleneck effect, in which the population was greatly reduced, resulting in inbreeding. On top of this, there was a global extinction that led to further inbreeding. When analyzing the cheetah’s DNA, this helped researchers to understand why the DNA of all the cheetah’s was so monotonous- there DNA was all very similar. For example, skin grafts were done on many different cheetah’s and were tolerated beyond the normal rate of tissue rejection (the similarity between their genomes allowed for successful skin grafts), hinting at the genetic similarity of the members of the cheetah species. But the scientists were interested in understanding how cheetah’s came to be so fast. They determined that natural selection caused this, leading to mutations that “boosted the animal’s muscle contraction, stress response, and regulation of energy releasing-processes.” Although Cheetah’s have the evolutionary advantage of speed, they are endangered; there are only an estimate 10,000 left and they face the threat of “loss of habitat and frequent fatal conflicts with humans.”

I think that this article is important, because it shows how by gaining DNA from a group can lead to a full genome, which we can compare to that of humans and other animals to gain a better understanding of the animal. Additionally, the genome can help researchers identify mutations, and find the advantageous mutations chosen by natural selection that helped the animal to survive, such as the mutations (i.e. muscle contraction) that enabled cheetah’s to survive by chasing prey and escaping predation. The results can also help to tell about major events that happened such as migrations or natural disasters that lead to changes in the populations DNA. The genomes of other animals can help tell us about that animal, allow us to make evolutionary connections, and tell us about the environment in which it lived.

I thought that this article was very well done, because it gave a lot of information on the specific cheetah that was sequenced, the background on the cheetah, and then information and results from the genome sequence. Although this article was very well done, I felt that there was lacking information on the specific genome mutations that caused the cheetah’s to be fast, and if there are any other animals with similar mutations. I also thought that there could have been more information on how the scientists came to believe that cheetahs are genetically monotonous, meaning that their genomes are almost identical. Overall, I thought that it was very well written, had lots of information, statistics and quotes from professionals who participated in this study.

New Procedure Allows Kidney Transplants From Any Donor

For my current event I read the article “New Procedure Allows Kidney Transplants From Any Donor” by Gina Kolata. Currently the waiting list for getting a kidney transplant is tens of thousands of people long, and many never get a transplant because they cannot find a match. A new study done by the New England Journal of Medicine has successfully been able to alter a patient’s immune system, so an incompatible kidney can be used. Those patients were more likely than those on a waiting list, or people who got kidneys from the deceased to live past eight years. The method used is called desensitization. It can significantly decrease the time spent waiting for a kidney, and on dialysis. About half of the

100,000 people in the United States waiting for a kidney transplant have antibodies that will attack transplanted organs, and almost 20 percent will accept virtually no kidneys. Some people give up on finding a kidney altogether, and just resort to dialysis.

Desensitization involves filtering antibodies out of the patient’s blood. The patient is then administered different antibodies to provide protection, while the body tries to make more. For an unknown reason regenerated antibodies are less likely to attack a new organ. If there are still troubles with the regenerated antibodies, the patient will be treated with drugs that destroy white blood cells that have the potential to attack the new kidney. Some of the drugs have yet to be approved for desensitization, and it runs at a steep $30,000. Transplants cost $100,000, but it is still significantly cheaper than dialysis, which costs $70,000 a year for life. Desensitization may also be used for live, and lung transplants, but it has yet to be done. The study looked at 1,035 across the country that had an incompatible donor, and the same number of people on a waiting list, and people who got kidneys from competitive diseased donors. After eight years 76.5% of the desensitization patients were alive, 62.9% on who got a matching donor, and 43.9% still on the waiting list.

This new study that proves the effectiveness of desensitization can vastly improve the lives of anyone with kidney failure. The waiting lists for kidney transplants are very long, and at this point for some people their search for a compatible kidney is hopeless. With desensitization people who otherwise would not have gotten a transplant now can. It can extend the lives of many people that would have had to live them on dialysis.

This article taught me a lot about the process to obtain a kidney transplant, and what it is like to wait for a kidney. It was well written, and the story at the end made it more personal. Everything was explained simply, and the author addressed most of the questions I had initially. I think it would have been better to include more details about the study earlier in the article. It would have also been nice to know how long the average person lives on dialysis, or after they get a kidney transplant from a deceased match, and how long they expect a person that goes through desensitization will live. They did not address any long term effects, or possible negative side effects of desensitization. Overall the article was informative, and simple.

Kolata, Gina. "New Procedure Allows Kidney Transplants From Any Donor." The New York Times. The New York Times, 09 Mar. 2016. Web. 09 Mar. 2016. <http://www.nytimes.com/2016/03/10/health/kidney-transplant-desensitization-immune-system.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science®ion=rank&module=package&version=highlights&contentPlacement=1&pgtype=sectionfront&_r=0>.

Boosting fat-burning by blocking Gq proteins

An international team of scientists has come one step closer to developing a way to melt off fat deposits. According to the article overweight people produce more white cells and no brown fat cells, “The white cells are responsible for bothersome fat deposits; conversely, the brown cells "burn off" unwanted pounds by releasing the energy stored in them in the form of heat.”   During the experiment it was “observed that there is a particularly high number of receptors in brown fat cells which bind to the Gq protein. The Gq protein performs an important function in information transfer.” The experiment consisted of activating the Gq protein in the mouse fat cells so the number and quality of the brown cells decreased.  At the end of the experiment, the team was able to discover a switch in the fat cells of mice and humans with which excess pounds can be burned off.

I chose to do a review on this article because it correlates with what we are doing in class, studying diabetes. Also, it is relevant to society because as the number of overweight people increases worldwide -- the risk of developing diabetes or cardiovascular disease becomes more of a reality. Therefore, many dream of an active substance which would simply melt off fat deposits. Now it is becoming a reality which is really exciting.

In my opinion, this article was not as strong as it could have been. However, one strength of the article, is that it was very informative, about this advancement. Another strength is the author identified what this means for the future. Although, the author does a great job of outline how the Gq protein is used, it would have been nice to have a quick summary identifying the Gq protein. Also, another improvement could be to go more in depth in the experiment specifically, I was a little unsure as to what happened.

Citation:

University of Bonn. "Boosting fat-burning by blocking Gq proteins." ScienceDaily. ScienceDaily, 9

March 2016. <www.sciencedaily.com/releases/2016/03/160309124814.htm>.

Scott Kelly Says a Year in Orbit Felt Like ‘Forever’

Chang, Kenneth. "Scott Kelly Says a Year in Orbit Felt Like ‘Forever’." The New York Times. The New York Times, 04 Mar. 2016. Web. 05 Mar. 2016.

The article that I read, Scott Kelly Says a Year in Orbit Felt Like ‘Forever,’ discusses the recent return of Scott Kelly, a NASA astronaut who spent 340 days in space. For the most part, the article was speaking about the differences that occur to the human body when in space versus when the astronauts are on Earth. Some of these changes are increased height and the flattening of the eyeball because of increased pressure of fluid from the lower part of the body floats up towards the head as a result of no gravity. NASA is working to study these changes throughout their missions and Scott Kelly is one of the contestants for the testing. Some of the ideas that NASA scientists are trying to prove is the idea that space changes the human body in ways we would have no imagined. Scott Kelly is being genetically compared to his twin brother in order to see the genetic differences that space can cause. So far, it has been found that the genetic changes were faster in Scott than in Mark. John Charles, an associate manager for NASA’s human research program said, “By looking at Mark’s results collected over the course of the year, we can see what the normal variations might be. Those will tell us what areas to investigate in the future.”

This article is very important to the scientific world because of its understanding or goal to understanding the human body and the changes that occur to it in space.With technology becoming more advanced, the knowledge and ingenuity of science is changing and expanding in many different directions very quickly. These types of studies are beneficial because they can help the medical and scientific field to understand what changes occur in space, whether or not they are dangerous to humans, and if people were to potentially live in space, what would needed to be created to avoid these dangerous space effects. Knowing and understanding how this works allows us to be one step closer to grasping and possibly having humans live in an area outside of Earth.  

In my opinion, I feel that this article was written very well. The author gave a great summary of the Scott Kelly’s background and gave details about the genetic changes between Mr. Kelly and his brother Mark. There was no time in which I was confused content-wise, nor was it repetitive or wordy. For this reason, I believe that the author was very clear and concise in his research and writing. Also, because there were some quotes that were included from experts on the subject from NASA, it allowed me to be comfortable and trust the information that was presented in the article. Overall, the author seemed to know a lot about what he was talking about, definitely a sign of a good writer.

Mr T-cell

I read an article titled “Mr. T-cell” which analyzes a new type of technology that could help cure cancer. T cells are used in the immune system to recognize molecules that are a threat to the body. Researchers extracted these cells and then create a custom built virus that is implanted in the cell with an entirely new set of DNA. The DNA tells the cells exactly what to look for and precisely where to attack in the body. This is difficult because the CD19 gene was only found in Acute lymphoblastic leukemia so it was easy for the cell to track it and not destroy other healthy cells. There are no other cancers that we know of which have a gene only specific to them and not found anywhere else in the human body. This would become an issue because the t cell would kill the healthy tissue where that gene is found as well. So far the results have been unprecedented in an ALL clinical trial where 93% of the patients are now in remission. The only complications were with a cytokine storm which is a runaway immune reaction due to the t cells replicating so quickly. This seems to only affect the patient’s whose cancer was the most widespread and two patients died from this complication.

This article is relevant because it is possible that in the future this could be a new way to treat and cure cancer. Our technology has increased so much that research into this treatment is going very quickly and there is more than just one use for the t cells. Scientists also believe that the cells stick around in the body for a while and could offer up to 10 years of protection against cancer.

This article was very clear and well written. I found it in the economist so of course there were no errors and the author made it easy to understand because it wasn't necessarily scientists reading it. The article gave me hope that a cure for cancer is possible and technology is drastically improving our chances of finding it.

"Mr T-cell." The Economist. The Economist Newspaper, 20 Feb. 2016. Web. 02 Mar. 2016.

In DNA, Clues to the Cheetah’s Speed and Hurdles

This article discussed the studies performed on cheetahs, determining their history and giving some hints as to “how the big cats became the world’s fastest land animals.” These studies were conducted by scientists at the Cheetah Conservation Fund in Namibia, on a cheetah rescued when it was a ten day old orphan, Chewbaaka. Later, more studies were done by scientists at the Theodosius Dobzhansky Center for Genome Bioinformatics at St. Petersburg State University in Russia, who collaborated with BGI-Shenzhen in China and the Cheetah Conservation Fund to analyze the entire genome of the species. After genetic analysis, scientists discovered that the cheetah has less than 5 percent of the genomic diversity (determined by variation in enzyme genes inherited by an animal’s two parents and is critical to its healthy reproduction and immunity to disease) of other wild cats, a level much lower than even inbred domestic dogs and cats and the lowest among the 30 mammals whose genomes have been sequenced. This therefore led to the scientists beginning to think that the cheetah was genetically monotonous several decades ago. These scientists in Russia then figured out the specific underpinnings of the cheetah’s genetic impoverishment and glimpsed the evolutionary chain of events that produced its unparalleled running speed. It was found that there were two specific points in history in which the genetic diversity of the cheetah was reduced. One of these instances was when the population bottlenecks were formed after cheetahs crossed the Bering strait into Asia. The other was late in the Pleistocene epoch when a global extinction event caused cheetah populations to crash. They examined how natural selection affected the cheetahs, firstly that the sequencing of the genome illuminated gene mutations that probably explain the sperm abnormalities seen in all cheetahs today, for they had the gene AKAP4, which likely block sperm development. The second effect natural selection had on the cheetahs, a positive effect, was their running ability. Eleven different genes showed evidence of mutations occurring over generations that boosted the animal’s muscle contraction, stress response and regulation of energy-releasing processes, which improved the cheetah’s running ability.

This article is important to society today because it discusses the possible extinction of yet another animal that played a large role in the world. The article shows the difficulty for the cheetahs to repopulate or enlarge their population because of the disadvantages they have in the field of reproducing, like having the sperm development blocking gene. This article is also relevant to us considering we previously studied genes and how a specific gene can result in traits or diseases passed down, which can also be seen in the cheetahs, which went through much interbreeding to keep the species from decreasing even more in population.

One strength of this article was how it went into depth explaining some of the genes and gene mutations that the cheetahs experienced, explaining some specific examples of traits in the cheetahs the scientists found. Although the article had many strengths, I still feel a few things could have been improved upon. For example, the article did not include much regarding the actual process undergone by the scientists performing the study, for it just gave a general overview of it. I would have liked if maybe it included more about this specific process undergone by the scientists, and not just the broad description of it.

Moffet, Barbara S. "In DNA, Clues to the Cheetah’s Speed and Hurdles." The New York Times. The New York Times, 29 Feb. 2016. Web. 01 Mar. 2016. <http://www.nytimes.com/2016/03/01/science/in-dna-clues-to-the-cheetahs-speed-and-hurdles.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science®ion=rank&module=package&version=highlights&contentPlacement=8&pgtype=sectionfront>.