Built-up earwax taken from a blue whale carcass offers insights into the creature’s life

earqwax

Using built-up earwax taken from a blue whale carcass, researchers have been able to reconstruct a picture of its life by the chemicals and hormones in its ears.

The whale in question was a male blue whale that died after it was struck by a ship near Santa Barbara, Calif., in 2007. Researchers removed a 10-inch ear plug from the carcass during a necropsy. They did a careful chemical analysis of it to measure what the whale had been exposed to in its lifetime. The study appeared in a recent edition of the journal Proceedings of the National Academies of Science.

The scientific community has been excited about the possibilities raised by the new method “once they get past the ‘eew!’ factor of it being earwax,” says Stephen Trumble, lead author on the paper and a biology professor at Baylor University in Waco, Texas.

Baleen whales are known to accumulate layers of earwax in their ear canal. These create a waxy plug that can be over a foot long. The earwax is laid down in layers, a dark one when the animal is feeding and a light one when the animal is migrating and eats very little. The layers are routinely used to determine whale ages.

Now by analyzing the chemicals, pollutants and other matter that accumulated in that wax, researchers were able to build a very complete picture of the animal’s life and exposure to chemicals.

The whale was likely born around 1995. It was exposed to large concentrations of persistent organic pollutants such as DDT and other pesticides in the first six months of its life, most likely while it was still nursing. Many mammals are known to pass chemicals through milk and researchers believe that’s what happened to this whale.

DDT is one of a group of persistent organic pollutants that can take decades to break down in the environment. Although it was banned in the United States in 1972 it is still found in the world’s oceans, and was present at higher levels when this whale was born.
There were also two spikes in its exposure to mercury, around ages 5 and 10. The researchers think these might have occurred as the animal migrated past the coast of California, possibly exposing it to higher levels of pollution than it encountered in the open ocean and when passing less polluted land masses.

When it was about 10 years of age researchers believe it became sexually mature because of increases in testosterone. Its stress hormones spike right around that time, too, which the researchers believe might have been linked to breeding competition or social bonds it formed during this period.

The method offers researchers a much easier and more precise way of measuring what whales are exposed to than previous methods, which included examining whale blubber, blood, feces and blowhole spray, says Sascha Usenko, a professor of environmental chemistry and one of the Baylor researchers.

Since their paper was published they’ve been getting offers of whale earwax specimens, called plugs,from around the world. “We’re going to receive one hopefully this week that’s about three and a half feet long from a bowhead whale from Barrow, Alaska,” Trumble said.

http://www.usatoday.com/story/news/nation/2013/10/10/whale-earwax-gives-researchers-peek-whale-life/2861591/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+usatoday-NewsTopStories+(USATODAY+-+News+Top+Stories)

Water Ice and Possible Organic Materials Discovered at Mercury’s North Pole

 

 

It’s time to add Mercury to the list of worlds where you can go ice-skating. Confirming decades of suspicion, a NASA spacecraft has spotted vast deposits of water ice on the planet closest to the sun.

Temperatures on Mercury can reach 800 degrees Fahrenheit (427 degrees Celsius), but around the north pole, in areas permanently shielded from the sun’s heat, NASA’s Messenger spacecraft found a mix of frozen water and possible organic materials.

Evidence of big pockets of ice is visible from a latitude of 85 degrees north up to the pole, with smaller deposits scattered as far away as 65 degrees north.

The find is so enticing that NASA will direct Messenger’s observation toward that area in the coming months — when the angle of the sun allows — to get a better look, said Gregory Neumann, a Messenger instrument scientist at NASA’s Goddard Space Flight Center in Maryland. [Latest Mercury Photos from Messenger]

“There is an ongoing campaign, when the spacecraft permits, to look further northward,” said Neumann, the lead author of one of three Mercury studies published online in the Nov. 29 edition of the journal Science.

Researchers also believe the south pole has ice, but Messenger’s orbit has not allowed them to obtain extensive measurements of that region yet.

Messenger will spiral closer to the planet in 2014 and 2015 as it runs out of fuel and is perturbed by the sun’s and Mercury’s gravity. This will let researchers peer closer at the water ice as they figure out how much is there.

Speculation about water ice on Mercury dates back more than 20 years.

In 1991, Earth-bound astronomers fired radar signals to Mercury and received results showing there could be ice at both poles. This was reinforced by 1999 measurements using the more powerful Arecibo Observatory microwave beam in Puerto Rico. Radar pictures beamed back to New Mexico’s Very Large Array showed white areas that researchers suspected was water ice.

A closer view, however, required a spacecraft. Messenger settled into Mercury’s orbit in March 2011, after a few flybys.  Almost immediately, NASA used a laser altimeter to probe the poles. The laser is weak — about the strength of a flashlight — but just powerful enough to distinguish bright icy areas from the darker, surrounding Mercury regolith.

Neumann said the result was “curious”: There were few bright spots inside craters.

Team member John Cavanaugh was pretty sure of what they were finding, Neumann recalled. Cavanaugh had been a part of NASA’s Lunar Reconnaissance Orbiter team, and he had seen a similar strange pattern on Earth’s moon when LRO found ice at the lunar poles in 2009.

Flash heating on Mercury would mix nearly all of its ice with the surrounding regolith – as well as with possible organic material borne to the planet by comets and ice-rich asteroids.

“So what you’re seeing is the fact that water ice can’t survive indefinitely in these locations because the temperatures apparently spike up,” Neumann said.

The team expected to find water ice on Mercury. Indeed, Messenger already drew a link this year between permanently shadowed areas on the planet and the “radar bright” spots seen from Earth.

All researchers needed to do was point their instruments in the right spot, seek out bright areas and then measure the temperature and composition.

Messenger’s neutron spectrometer spotted hydrogen, which is a large component of water ice. But the temperature profile unexpectedly showed that dark, volatile materials – consistent with climes in which organics survive – are mixing in with the ice.

“This was very exciting. You are looking for bright stuff, and you see dark stuff – gee, it’s something new,” Neumann said.

Organic materials are life’s ingredients, though they do not necessarily lead to life itself. While some scientists think organics-bearing comets sparkedlife on Earth, the presence of organics is also suspected on airless, distant worlds such as Pluto. Scientists say comets carrying organic bits smashed into other planets frequently during the solar system’s history.

Researchers are now working to determine if they indeed saw organics on Mercury. So far, they suspect Mercury’s water ice is coated with a 4-inch (10 centimeters) blanket of “thermally insulating material,” according to Neumann’s paper.

It will take further study to figure out exactly what this material is, but Neumann said the early temperature curves could show organic materials such as amino acids.

http://www.livescience.com/25132-water-ice-mercury-messager-discovery.html