Ultraviolet rays don't just bronze sunseekers on the beach. Underwater, they can give hammerhead sharks a suntan. And worse—give fish skin cancer. So says a study in the journal PLOS ONE. Researchers caught 136 coral trout in the southern Great Barrier Reef. Fifteen percent of them had black lesions on their skin: melanoma. Pathogens, toxic chemicals or UV rays can all cause melanoma. But DNA tests ruled out the presence of pathogens. And the fish were caught in the pristine waters of a marine sanctuary, so pollution wasn't to blame. Turns out, the trouts' cancer cells looked just like those of fish who'd been hit with UV radiation in the lab. So the researchers concluded that sunshine was the culprit. Makes sense, they say, because these trout live near the world's biggest hole in the ozone layer— meaning more exposure to UV rays. Another recent study, this one in the journal Science, says the severe storms delivered by climate change could punch new holes in the ozone layer, upping our dose of radiation on land and at sea. And that's no fish story.

What's the first thing you do when you get to a hotel room? Turn on the light, kick off your shoes and turn on the tube? If so, congratulations: you've likely just made a quick tour of the places in the room that harbor the most bacteria.Sure, there are a lot of bacteria in the bathroom. But that's not the hottest spot for bugs.Some of the highest concentrations of microbes were on the light switch, the carpet and the television remote. The findings were presented at the American Society for Microbiology's 2012 general meeting. The researchers sampled 19 surfaces from nine hotel rooms in three different states. They found that 81 percent of those surfaces had at least some fecal bacteria on them. But, of course, not all of these bugs are going to make you sick. The study was in part to help inform cleaning protocols. Some hotel chains are already pledging to keep their properties a little more germ-free. So your next stay might be a little cleaner. Just don't investigate CSI-style with a black light. You'll never be able to sleep.

Roosters greet the rising sun with crowing sound. But they also crow at other times. So are they .....responding... to the light? Or do they simply know that it's morning? New research says the latter: roosters crow because of internal time cues.The finding is in the journal Current Biology. Scientists .....controlled.... the light levels in rooster habitats. For two weeks, the birds experienced 12 hours of light followed by 12 hours of dim light. ....Consistent..... with the pre-dawn noises observed in wild fowl, the roosters began to crow about two hours before their rooms lit up. Then, for two weeks, the roosters lived in .....constant.... dim light. Yet they continued to crow about once a day—at intervals of 23.7 hours to be precise. Even without morning light, their circadian rhythms told them when dawn should be breaking. The birds also .....crowed.... in response to sudden light, and to the sounds of other roosters. But they were more likely to react when those stimuli .....occurred.... near dawn. Showing that you can't really keep a rooster in the dark about the time.