Wednesday, February 20, 2008

Clouds and the Life of Microbes

The New York Times has a very interesting story about clouds! Read lots more from Olivia Judson.

"But clouds present an extra difficulty. Most of the environments that we consider extreme — the icy, the acidic, the salty, the boiling, and so on — are fairly easy for microbes to adapt to, because the conditions remain relatively constant for long periods. The greater challenge comes when the environment contains extreme swings in conditions, as in a tide pool. Creatures that live here must be able to endure changes from wet to dry, cold to hot, as well as rapid fluctuations in how salty it is."


"Mostly, the cloudy residents are bacteria of various kinds. Samples of clouds taken from a meteorological station at the summit of Puy de Dôme, a mountain in central France with an elevation of more than 1,400 meters (almost 5,000 feet), turned up more than 71 strains of bacteria, as well as a variety of fungi; owing to the way the sampling was done, this is a massive underestimate of who’s up there. Of the bacteria detected, many appear to have come from the oceans. More than half have shown themselves capable of growing in cold temperatures, and some are even officially psychrophiles — lovers of cold. Which is to say, they grow when it’s cold, and not when it’s a bit warmer — unlike the bacteria on your food, which slow down when you put them in the fridge. One of the bacteria most often detected was Pseudomonas syringae; intriguingly, this critter has the ability to make ice crystals form around it at relatively warm (-2C, or 28.4F) temperatures.

As to their metabolism — the question of what such microbes “eat” — clouds are, apparently, more nutritious than they look. More nutritious, even, than some freshwater lakes. Cloud water contains a slew of compounds, from different types of organic acids and alcohols, to elements such as nitrogen and sulfur. Laboratory experiments have shown that for a growing bacterium or fungus, cloud water contains plenty of potential food."

Saturday, February 16, 2008

Only 5,000 Light-Years Away

I love to learn what scientists are saying about what they find in the universe - today, reported in Scientific American: Astronomers have discovered a pair of planets around a star 5,000 light-years away that resemble smaller versions of Jupiter and Saturn, hinting that solar systems like ours may be unexpectedly common. As in our own solar system, the closer of the two planets to their star is the larger one, 70 percent as massive as Jupiter; the more distant planet has 90 percent the mass of Saturn.

Let's face it, in universe terms this is very close. Now I am wondering for real if other intelligent beings are out there!

Wednesday, February 06, 2008

Looking at the way we think about others

I am interested in this study presented in Scientific American, but particularly in this part of the study mentioned below. Also, I could not resist using this image to illustrate the study, so I may as well be stereotyping groups just as the participants in this study.

"The experimenters used functional magnetic resonance imaging (fMRI) to scan the brains of Harvard and other Boston-area students while showing them pictures of other college-age people whom the researchers randomly described as either liberal northeastern students or conservative Midwest fundamentalist Christian students.

The categories were a ruse. The pictures were actually downloaded from an online dating website and randomly assigned to the two groups (which were an invention of the researchers), with each group holding similar racial and gender mixes.

The experimental participants, however, thought each person pictured really was from one group or the other because the experimenters contrived demographic information about each photo; this information was randomly reassigned to different pictures with each new experimental subject. The participants, then, were confronted with pictures of people who had randomly generated but coherent cultural and political identities already attached to them."