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Statistics show that “women live longer than males and are more able to fight off shock episodes” (Wiley 1). New Research suggests their immune system is also stronger. This is attributed to having two X-Chromosomes, while men only have one.

The X Chromosome has around 1098 genes whereas the Y Chromosome only has around 78. Out of 3,199 identified inherited diseases, 307 can be traced to mutations on the X Chromosome. Mutations on the X Chromosome affect males most because they “lack another copy to compensate.” X-Chromosomes contain 10% of all MicroRNAs, many of which have important functions in immunity and fighting cancer. MicroRNA: “tiny strains of ribonucleic acid which alongside DNA and proteins, make up three major macromolecules essential for life” (Wiley 2).

By targeting MicroRNAs scientist can study the reasons immunity is stronger in women. The technology to amplify MicroRNA is being completed currently. Geneticists at Emory University have discovered a technique for the amplification of genes on the X-Chromosome . It targets 800 eons. “Modern DNA sequencing techniques use the polymerase chain reaction (PCR) to isolate and "amplify" the target DNA scientists want to read. RainDance Technologies has developed a single molecule microdroplet-based technology that enables scientists to target up to 20,000 genomic loci in a single sample, saving time, space and cost while increasing reliability and ease of use” (Mondal 1)

A Single Origin: The Diversification of Orb Weavers

Orb weavers, known for their spiral-shaped webs, are some of the most adept spiders on the planet: thousands of species exist on every continent except Antarctica. On October 11, 2011 Proceedings of the Royal Society B published “Tangled in a sparse spider web: single origin of orb weavers and their spinning work unraveled by denser taxonomic sampling”; a study completed by researchers at the University of Copenhagen that found orb-weaving spiders first emerged during the Middle Triassic period, about 230 million years ago. The spiders then rapidly diversified, as a large variety of orb weavers emerged around the middle of the Jurassic period, about 170 million years ago.

Scientists had previously assumed that orb weavers diversified when flying insects did, in response to the need to specialize to catch different prey. Dimitri Dimitrov, an evolutionary biologist at the University of Copenhagen and the study’s first author, explains that his team’s research suggest “there is a no real relationship” between these two diversifications. The team’s work has shown that orb weavers diversified millions of years before flying insects.

The team used fossil records and DNA samples of existing species to create an evolutionary tree and timeline to find that orbs have a single origin.

Results also indicate that orb weavers’ diversification was in response to environmental factors, not to food shortage. Dimitrov believes that orb weavers diversified to create specialized habitats depending on their surrounding environment. Certain species specialize in webs for tall grasses, while others create webs for tall tree branches.

Sources

http://rspb.royalsocietypublishing.org/content/early/2011/10/25/rspb.2011.2011.short?rss=1

http://www.pnas.org/content/106/13/5229.short

RNA: Not Just a Helper

Many new categories of RNA have been discovered recently that show increasing evidence of the importance of RNA in gene expression beyond the transcription/translation process. These categories, previously thought to only exist in germ cells, have been found to play a vital role in the plasticity of the brain. One category, piRNA is found abundantly in the hippocampus and thought to express their own unique proteins. These RNA are also thought to be responsible for the bodies response to pathogens and is thought that their further investigation can help understand how to inhibit Hepatitis.

http://www.genengnews.com/gen-articles/rna-assumes-more-prominent-role/3887/?kwrd=Gene%20Expression

Fungus: The New Pesticide?

Resent studies of the genetic make up of Fungus have revealed their potential to replace pesticides in agriculture. Fungi have a very diverse genetic make up that is easily adapted to the environment. Furthermore, fungi can form a symbiotic relationship with plants and use their genetic flexibility to improve the growth of plants in certain regions. As of now, fungi have been found to help certain plants adapt better to their environment and work, as pesticides would, to decrease parasitic or detrimental surroundings from affecting their growth. Scientist are hoping that more research in this field could help to identify the specific genetic makeup of each fungus that helps it thrive in its specific region and use this to create a new form of area specific, natural pesticides.

http://www.sciencedaily.com/releases/2011/10/111031081915.htm

Randomness in Gene Expression

Recent research has found that the expression of certain "housekeeping" genes is random. While it is clear that certain genes are activated by certain outside factors, the genes responsible for proteins that regulate cell function are very random. In fact, it seems that these genes are not only expressed randomly, but that they do not communicate with each other or affect each other's expression in any way. The most interesting part is that this randomness works. Despite this lack of communication, the cells manage to produce enough proteins to continue function. These findings are important because they shows that the cells are able to function in a random environment and could help explain adaptation abilities.

http://www.sciencedaily.com/releases/2010/12/101205202508.htm

Cooked Foods Deliver Larger Amounts of Energy to the Body

The article I found discusses a recent study done at Harvard University that proves that cooked meat provides more energy than raw meat. This finding is significant because it shows that cooking has played a key role in "driving the evolution of man from an ape-like creature into one more closely resembling modern humans". The study was conducted by a student in Department of Human Evolutionary Biology at Harvard's Graduate School of Arts and Sciences named Rachel Carmody. For forty days she fed two groups of mice either meat or sweet potatoes that were prepared in four different ways: raw and whole, raw and pounded, cooked and whole, and cooked and pounded. Throughout the course of each diet, researchers observed the changes in each mouse's body mass, as well as how much they used the exercise wheel. The results showed that the mice received more energy from cooked meat than raw.

This discovery greatly contributes to our understanding of how humans evolved. Without the ability to control fire, 2.5 million years ago humans were eating only raw meat, but about 1.9 million years ago human bodies suddenly began to grow larger and their brains increased in size and complexity. Originally it was thought that this change was due to an increase of meat in their diet, but Carmody's research provides another hypothesis that "cooking provided early humans with more energy, allowing for such energetically-costly evolutionary changes". Additionally, the findings also point out the faults of the Atwater system, a "calorie-measurement tool used to produce modern food labels". The Atwater system only measures what has been digested and neglects to acknowledge the host of bacteria in the human gastrointestinal system that metabolize some of our food for their own benefit. This bacteria takes a good amount of the food we eat and therefore takes away the amount of food that is actually digested by the human. The research has shown though that one way to increase the value humans get is by processing food and cooking is one way to do so. Overall, this research has changed the way we look at food energy and it's role in human evolution. With all this said, we can now begin to alter recommendations and solutions for areas suffering from famine or areas suffering from energetic excess.

Original Article: http://www.eurekalert.org/pub_releases/2011-11/hu-wcc110411.php#top

Ancient DNA provides new insights into cave paintings of horses

This article focuses on the realism behind ancient cave paintings from the Paleolithic period. Essentially, researchers were searching for evidence supporting that white-spotted phenotypes of pre-domestic horses existed in the Paleolithic period. DNA studies have already produced the necessary evidence proving that bay and black phenotypes of pre-domestic horses existed. The argument in question is whether or not the artists behind these cave paintings were portraying their natural surroundings or if they were simply drawing random abstract images. The paintings in question are “The Dappled Horses of Pech-Merle” in France which shows white horses with dark spots dating back to 25,000 years ago.

The study consisted of researchers from six different countries genotyping nine coat-color loci in 31 pre-domestic horses from up to 35,000 years ago from different areas of Europe. The analysis consisted of bones and teeth samples from 15 different locations. The study found that 6 of the 31 samples (4 Pleistocene and 2 Copper Age) shared the gene associated with the leopard-spotting phenotype. 18 of the 31 had the bay coat color and 7 of the 31 had the black coat color.

Professor Michi Hofreiter, Department of Biology at the University of York said that the “results suggest that, at least for wild horses, Paleolithic cave paintings, including the remarkable depictions of spotted horses, were closely rooted in the real-life appearance of animals.” This in turn means that the paintings found in these caves reflect the natural environment of the humans who painted them. The research was led by Dr. Melanie Pruvost, Department of Evolutionary Genetics at the Leibniz Institute for Zoo and Wildlife Research and the Department of Natural Sciences at the German Archaeological Institute. According to Pruvost, “we can already see that this kind of study will greatly improve our knowledge about the past.” Hopefully these findings can help shed light on previous debates regarding whether or not the cave paintings had an abstract, underlying meaning, or whether they were simply a means of portraying what was seen on a daily basis in the European habitat.

Sources: http://www.boston.com/news/science/articles/2011/11/07/cave_painters_were_realists_dna_study_finds/

http://www.eurekalert.org/pub_releases/2011-11/uoy-adp110411.php