Non-Genetic Evolution Proposed Regarding American Obesity Epidemic

Dr. Edward Archer from the University of Alabama published a paper in Mayo Clinic Proceedings this month regarding non-genetic evolution [1]. Archer proposed that rapid increases in obesity within the United States are an indication of human evolution, or devolution, from a non-Darwinian sense. He claims that humans obese tendencies are a result of human living conditions, primarily the improved medical support as well as human choices regarding food and exercise. This is a highly controversial proposition due to the fact that it greatly contradicts Darwin's statements in his famous Origin of Species book which in a broad sense claimed that all species evolve slowly through a genetic pattern, and that they change primarily out of necessity. Therefore Archer's claims have now been considered as a direct threat towards the very fundamentals of which evolutionary science is based upon. If it is true that evolution can occur based on an individuals actions as well as through genetic inheritance it is certain that many of Darwin's own propositions are false. However, Archer's theories are still disputed as some may claim that what he is describing, the devolving of Americans into obese tendency, is not actually evolution at all but merely a change in human tendencies. In retaliation towards skeptics, Archer is quoted:

"This a priori constraint on heritability and evolution has no empirical or theoretical foundation; however, because theory affects research, clinical practice, and public health policy, the exclusion of nongenetic pathways for the intergenerational transmission of obesity and high-risk phenotypes has been unproductive. [2]"

In essence, he claims that the scientific community has for too long ignored the evidence presented by himself and others that non-genetic evolution is not only a possibility, but is a fundamentally sound theory. He later claims that Darwinian theories therefore ought to no longer be considered as utmost truth with in the scientific community.

This relates to the current unit at hand regarding Darwinian evolution on many regards. For one, it signifies the potential flaws, or at least incompletion, of Darwin's famous theories. While I myself am not entirely swayed towards adopting Archer's ideology, he does effectively raise the question about if we are fully learning the processes of evolution in academia. It also relates firmly to the application of the theory of evolution within modern day life. Due to the immensely slow nature of evolution, it is generally not a phenomenon that most people are aware of in their own lives. The proposition of non-genetic inheritance however can fluidly relates to the modern day issue of obesity within the United States and raises the question 'are we devolving ourselves?'

Sources

[1] http://www.mayoclinicproceedings.org/article/S0025-6196(14)00740-X/abstract
by Edward Archer
published January, 2014

[2] http://www.evolutionnews.org/2015/01/mayo_clinic_pap092421.html
by Casey Luskin
published 4 January 2014

Why Black Widow Spider Venom Is So Potent

Viegas, Jennifer. "Why Black Widow Spider Venom Is So Potent." Discovery News. 6 January 2015. 12 January 2015. <http://www.livescience.com/49333-why-black-widow-spider-venom-is-so-potent.html>

                Scientists have found that Black Widow spiders produce a similar toxic compound called latrotoxins like common house spiders. However the difference is that female balck widow spiders produce high amounts of toxic venom to the point that they must spin stronger webs to handle bigger caught prey. When bitten by one, the neurotoxin called alpha-latrotoxin attacks the victim's own nervous system causing the signals from each neuron to malfunction. Many spiders churn out toxins to help with their hunting, but occaisonaly they make a version that is not harmful to most people because it's "watered-down".On average 2,200 people get bitten by one, but eventually recover with medical treatment after 24 hours. Researchers have also found out that the spider's venom contains a mixture of other toxins that make the alpha-latrotoxin more effective.

                This relates to term 2 because scientists believe that these black widow spiders have evolved over the past few years to create such potent venom so it could expand its diet. Before they could consume small animals and reptiles, more smaller prey and even their mates, but now their food can be on the even larger scale. This shows they have evolved to cope with their eating conditions. This term we learned how organisms can adapt to a particular envrionment by improving its ability to survive and reproduce; black widow spiders are creating more toxic venom to kill larger prey, larger prey means more food, and more food means easier survival.

Radiation In Space

By: Melissa Gaskill 2/27/14

http://www.nasa.gov/mission_pages/station/research/news/micro7/#.VK8xujTF9yI

Gaskill, Melissa. "The Space Double-Whammy: Less Gravity, More Radiation." NASA. NASA, 27 Feb. 2014. Web. 8 Jan. 2015.


As missions into outer space increases, astronauts, cosmonauts, and scientist begin to discover that there is greater threats other than equipment malfunctions. While in space the human body is heavily effected by lack of gravity as well radiation.We are rarely affected by radiation because Earth's atmosphere blocks most of the harmful rays from the Sun. Radiation is harmful because it damages the DNA in cells, then when the DNA repairs itself mistakes in the coding an occur which could lead to the development of cancer. NASA estimates that one year in space can damage one-third of an astronauts DNA. This is large problem for long missions such as the nine month voyage to Mars. NASA is currently testing the effects of radiation on human fibroblasts which are the non-dividing cells in the body that make up the structure of organs and contributes to healing the body. Since the experiment will take place on the space station where there is no radiation, bleomycin will be used to simulate radioactive damage. From the results of the experiment NASA will develop technology to suppress the effects of radiation on living organisms. NASA will also see whether or not cells repair DNA more efficient in space or on Earth. The investigation will show any difference in cell function between Earth and space.

This relates to our study of DNA. It shows the importance of DNA in the human body and that even small changes in DNA can lead to mutations and other harmful activities. This also relates to a species ability to survive and thrive or the inability to do so in different environments. Since humans have evolved and adapted to the environment on Earth, the body has trouble functioning correctly in space. This is due to the absence of gravity which deteriorates muscles and effects the circulation of blood and other fluids. The lack of oxygen and the temperature also makes it impossible for humans to survive without the assistance of space equipment. Radiation's affect on the human body underlines the importance of how the Earth's atmosphere is suited for life and how vital it is to preserve it.            
     

World First: Scientists Observe DNA Shuttling Between Cells, Triggering Tumor Growth

Scientists have made a groundbreaking new observation, one of DNA of a particular type that actually shuttled or moved between the cells of an animal. The way this happens involves actually primarily not the genome within the nucleus but the much smaller genome of the mitochondria. Scientists observed mitochondrial DNA, or mtDNA, that could be transferred from healthy cells to tumor cells which would promote cancer growth. While the spread of cancer is evidently a very dangerous interaction, there also rises the new possibility that we may be able to replace malicious genes with synthetic and constructive ones instead! As previously known by scientists, mtDNA is very prone to mutations since there is not a very effective proofreading system for its genes, at times causing disease. Scientists believe that if they remove the mtDNA from cancerous cells they may be able to stop the tumors. However, when they tested it out they realized that it was uneffective and the tumor cells grew regardless. They realized then that mtDNA was present even without the mitochondria, and then made the discovery that it was migrating from other cells, though they are not quite sure yet where exactly it had come from (it was obvious though that it was from healthy, non-tumorous cells around them). The observation opens up a whole new field with lots of room for experiments and new discoveries.

This is relevant to the things we have learned regarding to genetic modification and the genomes of organisms in all sorts of way. The first connection, is link between how mitochondria have their DNA, relevant to how they may have originally been a separate organism that joined with other bacteria to create the first multicellular organism cells. But more largely, it relates back to how we could have possibly opened up all sorts of new doors in the field of genetic modification. For example, may it be possible for us to genetically alter some of the genes in our body and then possibly have the DNA migrate to the rest of the cells and end up with all of the cells genetically modified. Also, genetically modifying mtDNA could have other potential benefits that modifying regular DNA does not. Who knows what other key discoveries this one may lead to.


http://www.iflscience.com/health-and-medicine/world-first-scientists-observe-dna-shuttling-between-cells-triggering-tumor

Evolution Can Result in Formation, Loss of New and Elaborate Structures

http://www.universityherald.com/articles/14720/20150111/evolution-can-result-in-formation-loss-of-new-and-elaborate-structures.htm

The article discusses a study conducted by the University of California, Riverside that observed the loss of a specific trait in geckos. The scientists observed that geckos who had lost the natural adhesiveness on their feet due to evolution had gained the ability to run faster and burrow. The scientists noted that this loss of features is beneficial, and leads to biodiversity. The geckos observed in the study had moved into terrestrial environments where adhesive feet was no longer an advantage. The scientists also noted that observing the loss of a trait can tell a lot about the function the trait had.

The article is relative to out current study because it deals with evolution, and specifically, natural selection. The adhesiveness of the feet of the geckos become a disadvantage, and so those organisms who retained more adhesive feet did not survive to produce offspring as often as those with less adhesive feet. As a result, the trait was lost over time. This is a very good example of Darwin's principle of natural selection.

Loblolly Sets Record for Biggest Genome

Date Published: May 1, 2014 
Author: Ashley Yeager

Summary:

            The loblolly pine, Pinus taeda, supplies most of the paper products in the United States. It is a conifer tree that can grow up to 30 meters tall. Scientists recently finished mapping the loblolly genome, which has around 22 billion base pairs, about a year after announcing the project in 2013. The loblolly has even more DNA than the wheat plant, which had previously had the largest recorded genome at 17 billion base pairs. However, even though loblolly pines have a vast amount of DNA, the published genetic blueprints show that 82% of it is repeating information. Analysis also revealed DNA sequences in its genome that are related to resisting pathogens, which could further our knowledge on how loblollies and other pine trees fight disease.

Relevance: 
           In Term 2, we discussed DNA, genes, and genomes in class. A genome is the complete set of all the genetic material in an organism. This piece of news is about the sequencing of an organism's genome like in the Human Genome Project we read about, although this time, researchers were looking at pine trees instead of humans. The article compares the number of DNA base pairs in loblolly pines and wheat, as well as making a brief allusion to how DNA controls processes like fighting disease in an organism.


Yeager, Ashley. "Loblolly Sets Record for Biggest Genome." Science News. Society for  
           Science & the Public, 1 May 2014. Web. 11 Jan. 2015.
 
https://www.sciencenews.org/article/loblolly-sets-record-biggest-genome?mode=pick&context=151

New Way To Turn Genes On

December 10th, 2014

Summary:

Researchers from MIT have discovered a gene-editing system, originally developed to delete specific genes, that has shown it can be used to reliably turn on any gene in living cells. This new application for the gene-editing system should allow scientists to more easily determine the function of individual genes. This also enables rapid functional screens of the entire genome, allowing scientists to identify genes involved in particular diseases. The system relies of cellular machinery that bacteria use to defend themselves from viral infection. Before, this system could be used as a tool for turning genes off or replacing them with a different version, but now it is engineered to turn genes on, rather than knock them out. 

Relevance:

This relates to Term 2 of Biology because the gene-editing system they use is artificially mutating cells, which relates to our study on mutations. Also, by using screening the entire genome of a disease, such as cancer, scientists are able to locate certain genes which may cause cancer to recur and spread, and turn off those genes to prevent the spread of cancer. This second part relates to our short study on cancerous cells.

"New way to turn genes on." Biology News. N.p. 10 December 2014. Web. 11 January 2015. http://www.biologynews.net/archives/2014/12/10/new_way_to_turn_genes_on.html