Tasmanian Devils Evolve Resistance to Contagious Cancer

Saey, Tina Hesman. "Tasmanian Devils Evolve Resistance to Contagious Cancer." Science News. Society for Science & the Public, 30 Aug. 2016. Web. 28 Sept. 2016.

In 1996, in the northeastern top of Tasmania an epidemic began. This epidemic is a contagious facial cancer that is decimating present day Tasmanian devil populations. Particularly concerning is that in some places up to 95% of the devils have succumbed to the facial tumors, spread when the devils bite each other. In total the virulent tumor has wiped out nearly 80 percent of the global Tasmanian Devil population. The possibility and reality of decreasing Tasmanian devil numbers is a huge problem. Devils are important to the ecosystem of Tasmania and serve as secondary consumers. The loss of all devils would alter the food chain and result in serious imbalances that may lead to even more imbalance. However, this article asserts that there may still be hope for the survival of these important marsupials, in the form of genetic variation. It has been hypothesized, through numerous studies, that a variation in the devil’s single nucleotide polymorphisms (SNPs) may be the answer to the problem of cancer. Researchers have stated that the “Two regions of the genome in all three of the devil populations contained SNPs that fit the profile. Because the two regions changed in all three populations, the change probably didn’t happen by chance.” These resistant variants do not appear to be new mutations due to the fact that there has not been enough time for a helpful mutation to arise and spread across the island. Most likely the variants were already present in the local population, albeit a minority previously, and when the disease arose the genetic individuals rose to prevalence through the process of natural selection. However, researchers still aren’t exactly sure which genes boost survival of the devils or how they work. In fact, researches such as evolutionary geneticist Andrew Storfer have even hypothesized that, “The variants don’t necessarily make devils completely immune to the tumor; the results would look the same if the variants just allow infected individuals to live long enough to pass along their genes, says Storfer. More undiscovered genes may also contribute to the devils’ survival,

This article is extremely important to people today, even here in New York. Although Australia is located across the globe, just like everywhere else, it has an ecosystem which is important to the Earth’s biome as a whole. As Tasmanian Devils keep dying at an alarming rate,  a great number of worries that have arisen. The pressure is on to try and find a cure/end of the spreading of such a terrible and debilitating disease. If Tasmanian Devils are decimated completely such a disappearance could have immense effects on the ecosystem. As secondary consumers disappear,  prey populations may rapidly expand, and producers decrease. There will be an extreme imbalance, which is not beneficial on a local or global scale. Besides the environmental impact of species loss, a greater importance is that scientists studying the marsupials may be able to learn how the creatures have essentially become immune to cancer. By observing more closely the genetic variation of facial cancer survivors vs facial cancer non-survivors, perhaps scientists will be able to derive a certain gene or series of genes that essentially combats cancer. A genetic disease, cancer is the one of the top causes of death across the globe. Therefore, these Tasmanian Devils could hold the key to a larger epidemic throughout the world. With the rapidly advancing field of genetic modification, perhaps one day our genes could be altered in order to prevent cancer, and it would all be because of these little marsupials.

The author of this article, Tina Hesman Saey, overall wrote a wonderful piece. I particularly enjoyed her use of quotes as well as her evident in-depth research about the topic. In addition, Saey used a great infographic/map that displayed how the contagious tumor has spread throughout Tasmanian Devil populations. This infographic/map enhanced the numbers of the article with a more qualitative approach. However, there are a few areas upon which Saey could improve. Primarily, I felt there should be more quantitative data. Now, perhaps there was not a lot of data available, but regardless there was still some as the original study had been published in a well-regarded scientific journal. Saey should perhaps view the study more intently and add data as relevant. Additionally, I felt Saey could have added more about the ecosystem impact that losing Tasmanian Devils would cause. This is an important issue and a lack of analysis on environmental effects is a good opportunity missed. By simply researching how secondary consumers affect ecosystem it would have been easy to include at least a paragraph discussing this important side of the research.