Evidence for Big Bang Theory found in meteorites
The Big Bang Theory hypothesizes that the solar system was born thanks to the death of a core collapse star, resulting in a supernova. The recent discovery of aluminum and iron isotopes in various meteorites — the forms of which are absent on Earth — has provided researchers with the evidence to substantiate the Big Bang Theory.
The discrepancy in the presence of particular isotopes on Earth suggests that although the individual grains of matter were evenly spread by the initial supernova, they were subsequently sorted by size, thus becoming disproportionately distributed throughout the solar system. By examining meteorite sample grains less than 100 nanometers in diameter, the researchers were able to identify chemical variations from one meteorite grain to the next. Since some of these chemicals are only present in specific types of supernovae, the initial Big Bang Theory has been re-examined to specify that at least one star explosion must have contributed to the matter within our solar system. —Alexandra I. Eremia
Source: University of Chicago
Epigenetics may determine ants’ position in caste system
Social insects like bees or ants have long been studied for the remarkable division of labor they utilize while performing basic tasks. In Harpegnathos saltator ants, sterile workers do the food shopping and heavy lifting, while the queen spends her days laying eggs and being fed royal jelly — ultimately living 10 – 500 times longer than the workers.
Workers and queens are genetically identical, so how do such different behavioural and life history features arise from the same DNA sequence? Recent work published in Science by Roberto Bonasio and colleagues has started providing answers. The authors measured gene expression in workers and gamergates, workers destined to be the next queen, and found that gamergates have higher expression of several genes that may regulate life span.
Although the researchers do not know the underlying cause of the increased expression, they speculate that epigenetics — the chemical modifications of DNA that alter the accessibility of genes for expression, thus switching genes on or off — may be responsible. —Heather Maughan
Source: Discover
Pro-smoking clips not yet restricted on YouTube
Public health researchers George Thomson and Nick Wilson of the University of Otago have claimed that Internet laws banning tobacco advertising are not being actively implemented for videos on YouTube. Thomson and Wilson found a plethora of pro-tobacco videos posted by YouTube users, and call this “indirect marketing activity by tobacco companies.”
Their methodology includes recording the frequency of public viewings of tobacco ads, and whether or not smoking is portrayed as positive. They found that Marlboro videos were the most popular, and that approximately three quarters of the content from all the clips included a pro-tobacco message.
Representatives from tobacco companies have explained that they do not believe this advertising should be allowed on the Internet. They even stated that they do not promote or advertise on the Internet. However, this research suggests that tobacco companies indirectly support these clips by simply allowing them to stay online. Thomson and Wilson suggest that governments should extend and enforce advertising restrictions upon Internet sites. —Cristina Olteanu
- Source: New Scientist
