Extremophiles: Life on the Edge

The possibility of life on Mars and other planets and moons has been debated for as long as we have known about those planets. Now that water has been found on the Mars, that possibility is more believable than ever. Sure, conditions are fierce on Mars, but research here on planet Earth reveals that life forms can be tough. In fact, wherever it was once thought that no life could exist, more and more organisms are being found that not only live, but thrive and evolve.

Hot Springs

The boiling waters of Yellowstone National Park and other extreme thermal environments have species of thermophiles, or organisms that thrive in temperatures that would kill most living things. These thermophiles have specialized enzymes that keep their DNA from unraveling the way other life forms would. Chemicals from various thermophile species are used for a range of biochemical applications, such as DNA fingerprinting technology. Image by Flickr user v1ctory_1s_m1ne.

The Dead Sea


The Dead Sea has such a high saline content that pillars of salt form on its banks. Yet Halobacterium salinarum lives in its waters. Halobacterium is one of the most ancient of microbes, and depends more on light for survival than on oxygen. It adjusts its own needs according to the available light and oxygen. Image by Flickr user CharlesFred.

Toxic Sludge


A copper mine in Montana was abandoned in 1983. As water filled the remaining hole known as the Berkeley Pit, minerals and metals leeched out and made it extremely acidic and poisonous. No fish or plants survived in the toxic water. It was thought to be completely dead until 1995 when a scientist recovered a slime that contained Euglena mutabilis, This protozoan manipulated its immediate environment to make it more livable! Researchers eventually found over 160 different species of microorganisms in the polluted water, some of which are being studied for use in cancer treatment. There is hope that Euglena mutabilis will eventually clean up the toxic water. Image by Linda Amaral Zettler and David Patterson.

Beneath the Great Lakes


Sinkholes deep beneath the Great Lakes have a very different chemical makeup from the water above. These pockets are filled with salt, acid, and sulfur, but have purple cyanobacteria that use sulfur instead of oxygen for photosynthesis. Other species that live too deep for sunlight to penetrate live on sulfur without photosynthesis.

Sea Floor Volcanos


In the depths of the Pacific ocean, volcanic vents support life too far down to take advantage of any sunlight at all. Tubeworms and giant clams thrive in volcanic environments by feeding on smaller species that survive only on chemicals without the advantage of photosynthesis. Image credit: NOAA.

High-altitude Volcanos


The Socompa volcano is 20,000 feet high in the Andes mountains. Conditions there include little oxygen, lack of water, ultraviolet radiation, and methane. But scientists have found moss, algae, and over a hundred species of bacteria living in the shadow of Socompa. The area has been compared to Mars in its ability to sustain life.

In the Clouds


Bacteria even live in the clouds! These microbes act as particles that ice form around and fall as snow or rain. They are called biological ice nucleators. Nucleators are found in plants and soil and are thought to ride on pollen as it is blown into the atmosphere. The part of the bacterial life cycle spent on vegetation may sustain an ice nucleator during its ride in the clouds, and the cloud seeding may be a mechanism for spreading it to distant parts of the earth.



No look at extremophiles would be complete without tardigrades, or water bears. These tiny animals are found in various extreme conditions on earth. They can survive hot and cold temperatures, radiation, lack of food and water, and even in a vacuum. The European Space Agency sent tardigrades into orbit in 2008, where they were exposed to cosmic radiation, solar radiation, and vacuum pressure. The space tardigrades were in a dormant state during the flight, which means their metabolism was slowed down considerably -a method they use to weather extreme conditions on earth. After returning from their adventure, they lived and even reproduced! Image by Flickr user Goldstein lab - tardigrades.

Beneath Antarctica?


Two miles beneath the ice of Vostok Research Station in Antarctica, a huge freshwater lake has been isolated from the rest of the world for millions of years. The water is below freezing temperature, but stays liquid because of the pressure from the ice above. Researchers have not yet broken through to the water, but samples of ice just above the lake reveal the presence of microbe fossils. The lake is saturated with oxygen due to the temperature and pressure, and has been compared with the environments of Jupiter's moon Europa and Saturn's moon Enceladus. There are plans to send down a probe called a cryobot, but extreme care will be taken to preserve the pristine conditions of the isolated lake.

The Surprising Link Between Language and Depression

Skim through the poems of Sylvia Plath, the lyrics of Kurt Cobain, or posts on an internet forum dedicated to depression, and you'll probably start to see some commonalities. That's because there's a particular way that people with clinical depression communicate, whether they're speaking or writing, and psychologists believe they now understand the link between the two.

According to a recent study published in Clinical Psychological Science, there are certain "markers" in a person's parlance that may point to symptoms of clinical depression. Researchers used automated text analysis methods to comb through large quantities of posts in 63 internet forums with more than 6400 members, searching for certain words and phrases. They also noted average sentence length, grammatical patterns, and other factors.

What researchers found was that a person's use (or overuse) of first-person pronouns can provide some insight into the state of their mental health. People with clinical depression tend to use more first-person singular pronouns, such as "I" and "me," and fewer third-person pronouns, like "they," "he," or "she." As Mohammed Al-Mosaiwi, a Ph.D. candidate in psychology at the University of Reading and the head of the study, writes in a post for IFL Science:

"This pattern of pronoun use suggests people with depression are more focused on themselves, and less connected with others. Researchers have reported that pronouns are actually more reliable in identifying depression than negative emotion words."

What remains unclear, though, is whether people who are more focused on themselves tend to depression, or if depression turns a person's focus on themselves. Perhaps unsurprisingly, people with depression also use more negative descriptors, like "lonely" and "miserable."

But, Al-Mosaiwi notes, it's hardly the most important clue when using language to assess clinical depression. Far better indicators, he says, are the presence of "absolutist words" in a person's speech or writing, such as "always," "constantly," and "completely." When overused, they tend to indicate that someone has a "black-and-white view of the world," Al-Mosaiwi says. An analysis of posts on different internet forums found that absolutist words were 50 percent more prevalent on anxiety and depression forums, and 80 percent more prevalent on suicidal ideation forums.

Researchers hope these types of classifications, supported by computerized methods, will prove more and more beneficial in a clinical setting.

[h/t IFL Science]

Pop Culture
The ‘Scully Effect’ Is Real: Female X-Files Fans More Likely to Go Into STEM

FBI agent Dana Scully is more than just a role model for remaining professional when a colleague won't stop talking about his vast governmental conspiracy theories. The skeptical doctor played by Gillian Anderson on The X-Files helped inspire women to go into STEM (science, technology, engineering, and math) careers, according to a new report [PDF] from the Geena Davis Institute on Gender in Media, which we spotted at Fast Company.

“In the world of entertainment media, where scientists are often portrayed as white men wearing white coats and working alone in labs, Scully stood out in the 1990s as the only female STEM character in a prominent, prime-time television role,” the report explains. Previously, anecdotal evidence has pointed to the existence of a “Scully effect,” in which the measured TV scientist—with her detailed note-taking, evidence-based approach, and desire to autopsy everything—inspired women to seek out their own science careers. This report provides the hard data.

The Geena Davis Institute surveyed more than 2000 women in the U.S. above the age of 25, a significant portion of whom were viewers of The X-Files (68 percent) and women who had studied for or were in STEM careers (49 percent). While the survey didn’t ask women whether watching Dana Scully on The X-Files directly influenced their decision to be a scientist, the results hint that seeing a character like her on TV regularly did affect them. Women who watched more of the show were more likely to say they were interested in STEM, more likely to have studied a STEM field in college, and more likely to have worked in a STEM field after college.

While it’s hard to draw a direct line of causation there—women who are interested in science might just be more inclined to watch a sci-fi show like The X-Files than women who grow up to be historians—viewers also tended to say Scully gave them positive impressions of women in science. More than half of respondents who were familiar with Scully’s character said she increased their confidence in succeeding in a male-dominated profession. More than 60 percent of the respondents said she increased their belief in the importance of STEM. And when asked to describe her, they were most likely to say she was “smart” and “intelligent” before any other adjective.

STEM fields are still overwhelmingly male, and governments, nonprofits, schools, activists, and some tech companies have been pushing to make the field more diverse by recruiting and retaining more female talent. While the desire to become a doctor or an engineer isn’t the only thing keeping STEM a boy’s club, women also need more role models in the fields whose success and accomplishments they can look up to. Even if some of those role models are fictional.

Now that The X-Files has returned to Fox, perhaps Dana Scully will have an opportunity to shepherd a whole new generation of women into the sciences.

[h/t Fast Company]


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