Weekly Science Roundup #24

Weekly Science Roundup time! This time, with 100% more Thanksgivings leftovers. Eating some pumpkin pie as I write. Yum.


1. Comet ISON Only Mostly Dead

Something has survived...

Comet ISON has been talked about for over a year now. The media hyped it as a comet to rival the moon in brightness, "coming December 2013!". While that was definitely hype, scientists were quick to point out that there was a possibility the media actually wouldn't be too far off this time.

As the comet drew closer to us, it was looking pretty good, but it had a risky trip around the sun coming on Thanksgiving day. If it made it, it would loop around and come back to us, visible in the evening sky...potentially gorgeous!

Sadly, it didn't seem to survive its trip. However, NASA's SOHO spacecraft observed something swing around the sun and come back into view after the comet disappeared. So perhaps the comet wasn't as dead as it first seemed. Instead of burning up completely, it is more likely that the nucleus of the icy/dusty comet broke up and now there is a smear of leftover material hurtling through space.

Is this smear bright enough for us to see with our bare eyes? Will it be a gorgeous light show? Probably not. But it's still hard to tell for certain. Maybe it will surprise us. After all, in the wise words of Phil Plait,

"Comets and cats are equally predictable."

2. Corals Hurt by Pollution May Have Fast Recoveries

Bleached Coral. Photo by Bruno de Giusti.

The bad news: a new study has confirmed the long-suspected concept that pollution in the ocean really does hurt coral. Badly. The presence of pollution doubled the amount of bleaching in coral over a three year study period. When coral is "bleached", it means the animal is stressed (yes, coral is an animal). This often is a precursor to death.

The good news is the same study showed that once the pollution was removed, the corals recovered within ten months. WOW! This is genuine evidence that programs to remove ocean pollutants can have a serious, strong, and fast effect on marine health. This is fabulous, and I hope it lays the foundation for efforts moving forward to clean up the ocean.


3. Crocodiles and Alligators Might Use Tools

We know birds use tools, so this shouldn't be a huge shock. Birds and crocodylians are both members of Archosauria, and share many behavioral traits such as nesting tendencies, singing, and parental care of offspring.

Now, a study by croc specialist Vladimir Dinets shows that gators and crocs seem to use "lures" to catch their prey. You want to click on that link. There's a great picture of a crocodile with sticks on its head.

The trick is simple. A gator or croc will use sticks to lure in birds who are in the middle of building nests. The birds swoop down to get the sticks off the predator's camouflaged head, and SNAP. Dinner.

The reason this is likely tool use (rather than just random chance of sticks being atop crocodile heads), is that this is only noticed during nesting season for particular bird species. Also, this isn't a special time of year when sticks are more common on the water or anything, either. This appears to be a deliberate act by crocodile and alligator species to gather sticks and hang out near birds that are in need of nesting supplies.

Neat! I look forward to further study. I love learning about surprising animal intelligence.