Wednesday, March 9, 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.


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.

1 comment:

  1. Freddie Reichel
    I enjoyed reading the review of the New York Times article, “In DNA, Clues to the Cheetah’s Speed and Hurdles.” The summary was clear and concise. Through a cheetah named Chewbaaka, scientists have uncovered how the cheetah became the world’s fastest land animal. Geneticists were able to draw his blood and six other cheetahs from Namibia and East Africa. This blood sample has been used to sequence the species’ complete genome; its full set of chromosomes. Genomic analysis confirmed scientists suspicions that the cheetah is “genetically monotonous.” The research was easy to comprehend. Conducted by scientists at the Theodosius Dobzhansky Center for Genome Bioinformatics at St. Petersburg State University in Russia, researchers collaborated with BGI-Shenzhen in China and the Cheetah Conservation Fund to analyze the entire genome of the species. These scientists figured out the specific underpinnings of the cheetah’s genetic impoverishment and the evolutionary sequence of events that created the cheetah’s unparalleled running speed. The research scientists focused in on the series of mutations of a specific timetable. The international team of geneticists calculated exactly when these population bottlenecks occurred. The cheetah’s incredible running ability is due to natural selection. Eleven different genes showed evidence of mutations over generations that boosted the animal’s muscle contraction, stress response, and regulation of energy-releasing processes. Scientists discovered the reason for the lack of genetic diversity in the cheetah and why the specific attributes of the cheetah exist. The cheetah is an endangered species, as illustrated by the fossil records, because of inbreeding, due to the migration across the Bering Strait into Africa. The cheetah is the fastest running animal on land because of both natural selection and mutation. Eleven different genes showed evidence of mutations over generations that boosted the animal’s muscle contraction and stress response. In addition, this research was relevant to what we are learning in class. By examining fossils from specific periods and eras of the earth, scientists unearthed evidence of mutations and genetic diversity. The review could have been improved by utilizing more quotations from the scientists involved in the research. The article could also be improved by describing prior research and whether it differs from the current discoveries.
    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. .

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