Half of all frogs will disappear
A massive study on the state of amphibians today suggests that almost half of all frogs, newts and salamanders will go extinct within 100 years. Scientists have known for years that some amphibians are dying out from loss of habitat, but many other species are disappearing for no known reason. Some biologists think that a fungus that lives on the skin of frogs may be responsible; others think climate change may be to blame, as thin-skinned frogs are particularly susceptible to dryness, UV radiation and heat. Whatever the cause, scientists believe humans are clearly to blame for the rapid disappearance of this entire group of animals.
-Zoe Cormier
Source: Nature
Cell phones double risk of tumour
A Swedish study suggests that cell phone use can double your risk of developing acoustic neuroma, a benign form of cancer that develops on the nerve connecting the ear to the brain. Researchers found that people who use cell phones for ten years or longer have a one in 50,000 chance of developing the cancer, compared to one in 100,000 for non-users. The study contradicts the findings of a Danish study released in January, which found no link between cell phones and acoustic neuroma, but did find that cell phone users had larger tumours than those that had never used cell phones. But the Swedish study looked at a twice as many people as the Danish study, which may give their findings more credibility. They also found that the tumours tended to occur on the side of the head people had held their phone to. Five European countries plan to take on a massive study, looking at 250,000 people in total, to verify the results.
-Z.C.
Source: Nature
Aggression built to spiral
Biologists in Holland and Hungary have found in the rat brain a loop that links stress hormones to the aggression center in the brain. Stimulating the aggression center raises levels of stress hormones, which in turn fuels the aggression center, which leads to the production of more stress hormones, and so on. Aggression and stress can together rise extremely quickly. Researchers think this could explain why aggressive behaviour can escalate so easily and so quickly sometimes, and why small annoyances can sometimes cause people to lash out violently.
-Z.C.
Source: The Guardian
It’s Alive!
Now that they have sequenced the genome of a gigantic virus known as the Mimivirus, scientists think that it may actually be alive, making it the first virus that can be classified as such. Biologists have debated for decades on whether viruses are truly living organisms, or just jumbles of large molecules stuck together. Moreover, viruses are made up of a few strands of genetic material-DNA or a similar material, RNA-surrounded by a coat of proteins. To be classified as “alive,” a creature must be able to reproduce on its own. Viruses cannot; they must get inside other cells, insert their DNA into the host’s DNA, and use the machinery of the cell to replicate. But the Mimivirus has the genes necessary to reproduce on its own. It also shares many other characteristics with normal cells: it has both RNA and DNA, it can make its own proteins, and it can repair its DNA if it is damaged. The virus is so different from all other life forms that it could be the missing link that led to the formation of living complex cells like ours.
–Z.C.
