Unlikely life thriving at Antarctica’s Blood Falls


April 23, 2009

An unmapped reservoir of briny liquid chemically similar to sea water, but hidden under an inland Antarctic glacier, appears to support microbial life in a cold, dark, oxygen-poor environment - a most unexpected setting to be teeming with life.

The McMurdo Dry Valleys of Antarctica are devoid of animals and complex plants and scientists consider them to be one of the Earth's most extreme deserts. The Valleys receive, on average, only 10 cm (3.93 inches) of snow each year. Despite the lack of precipitation, during the Antarctic summer, temperatures rise just enough for glaciers protruding into the valleys to begin melting. The meltwater forms streams that enter lakes covered by ice that is two-to-three-stories thick. Download Full Image

Even less forgiving are the conditions found below the Taylor Glacier, an outlet glacier of the East Antarctic Ice Sheet in the otherwise ice-free Dry Valleys. The lack of light beneath the glacier makes the process of photosynthesis improbable, causing researchers to wonder how organisms found below the glacier could survive.

The research, which appears in the April 17 issue of Science, suggests that over the past 1.5 million years the microbes adapted to manipulate sulfur and iron compounds to survive. In place of photosynthesis, the microbes converted Fe(III) to Fe(II) to create food and energy.

The study was led by Jill Mikucki, a National Science Foundation-funded researcher at Dartmouth College. Mikucki and a team of researchers based their analysis on samples taken at the ominously, but aptly named Blood Falls, a water-fall-like feature at the edge of the glacier that flows irregularly, but often has a strikingly bright red appearance in stark contrast to the icy background.

The key piece of data supporting the hypothesis that the microbes were in fact surviving by turning Fe(III) to Fe(II) came from samples analyzed by Ariel Anbar, one of the authors of the study and an associate professor at Arizona State University, and researchers in his group, using instruments in the W. M. Keck Laboratory for Environmental Biogeochemistry at ASU.

"We found that the isotopes of Fe(II) in the brines are shifted in a way that is consistent with this microbial process," said Anbar, who holds joint appointments in the School of Earth and Space Exploration and the Department of Chemistry and Biochemistry in the College of Liberal Arts and Sciences.

Even the earliest explorers noted the massive red stain at the snout of the glacier and speculated as to what may have caused it. Some guessed that red alga was responsible for the bright color. "In fact, the red color is a result of all that Fe(II) produced by bacteria," said Anbar. "When the Fe(II)-rich water reaches the surface, the Fe(II) reacts with oxygen in the air to make Fe(III) compounds that are sort of like rust. That's the source of the red color."

The microbes are remarkably similar in nature to species found in marine environments, leading to the conclusion that the populations under the glacier are the remnants of a larger population of microbes that once occupied a fjord or sea that received sunlight. Many of these marine lineages likely declined, while others adapted to the changing conditions when the Taylor Glacier advanced, sealing off the system under a thick ice cap.

In the paper, however, Mikucki and her colleagues argue that the creatures that survive under the Taylor Glacier are both far more exotic and far more adaptable than the early explorers thought.

Because the outflow from the glacier follows no clear pattern, it took a number of years to obtain the samples needed to conduct an analysis. Finally Mikucki obtained a sample of an extremely salty and clear liquid for analysis.

"When I started running the chemical analysis on it, there was no oxygen," she said. "That was when this got really interesting; it was a real ‘eureka' moment."

Further genetic analysis suggests that of the relatively small numbers of microorganisms found in the brine, "the majority of these organisms are from marine lineages," she said.

In other words, microorganisms more similar to those found in an ocean than on land, but capable of surviving without the food and light sources available in the open ocean.

"The salts associated with these features are marine salts, and given the history of marine water in the dry valleys, it made sense that subglacial microbial communities might retain some of their marine heritage," she added.

This led to the conclusion that the ancestors of the microbes beneath the Taylor Glacier probably lived in the ocean many millions of years ago. When the floor of the Valleys arose more than 1.5 million years ago, a pool of seawater from the fjord that penetrated the area was trapped. The pool was eventually capped by the flow of the glacier.

The briny pond, whatever its size "is a unique sort of time capsule from a period in Earth's history," Mikucki said. "I don't know of another environment quite like this on Earth."

Life below the Taylor Glacier may help scientist address questions about life on "Snowball Earth", the period of geological time when large ice sheets covered the Earth's surface. But it's also a rich laboratory for studying life in other hostile environments, including the subglacial lakes of Antarctica and perhaps even on other icy planets in the solar system such as below the Martian ice caps or in the ice-covered oceans of Jupiter's moon Europa.

 

Nikki Cassis

marketing and communications director, School of Earth and Space Exploration

Green Jazz series concludes with rising star


April 23, 2009

One of jazz’s rising stars will blaze across a Downtown Phoenix venue and conclude a popular concert series that blends music and sustainability.

International recording artist and Phoenix resident Dominic Amato will headline ASU’s Green Jazz Series concert, which takes place at 7 p.m. on Monday, April 27 at the Herberger Theater, 222 E. Monroe St., Phoenix. Admission is $20 for general admission and $40 for VIP seating.  Jade Alexis Johnson, a junior at Xavier College Preparatory, will open for Amato. Download Full Image

The series, which started in September 2008, is sponsored by Arizona State University Online, the Herberger Theater Center, Brotha Love Productions and Southwest Green Magazine.

“We’re hopeful the concert series has helped shift awareness and promoted the culture of green living while helping low-income households,” says Mernoy E. Harrison, Jr. ASU Online and Extended Campus vice president and executive vice provost. “The premise is that jazz is the bridge between music and sustainability.”

Proceeds from the concert series will support the Green Revival Initiative (GRI), a Phoenix-based sustainability project. Through the use of cost-effective green technologies such as compact fluorescent lights, low-flow shower heads and water heater blankets, GRI seeks to mitigate increasing energy costs for approximately 1,000 low- and fixed-income households in the Phoenix metropolitan area.

The initiative will help low-income families make the conversion to a sustainable lifestyle.

“The GRI recognizes that there is a cost to convert to a green lifestyle and those who need it the most might not be able to make that conversion,” says George Brooks, publisher of Southwest Green Magazine, an event sponsor. “We believe that once these conversions are made, each household could save anywhere from $300 to $500 annually.”

A green business networking event that includes informational booths, a green art display and promotional giveaways starts at 5:30 p.m. and will precede a 6:45 p.m. fashion show hosted by Jean Paul Jeune and 7 p.m. concert. For more information or to reserve a booth, call (602) 363-1677 or e-mail Publisher">mailto:Publisher@sw-green.com">Publisher@sw-green.com.

Amato, who has lived in the Valley since 1990, is one of the Valley’s best known names in smooth jazz.  The saxophonist, whose influences include Miles Davis, John Coltrane, David Sanborn and Chick Corea, ascended into the national spotlight as a member of group Turning Point.  Their 2005 recording of Matador was a blending of instrumental rock and blues with edgy world beat textures.

“Turning Point was a valuable experience for me because it boosted my confidence as a musician,” Amato said. “All of a sudden I went from playing jazz in local venues to performing in front of an international audience. You can’t help but grow as an artist from that kind of experience.”

Four years later Amato made the transition from sideman to bandleader with the 2009 release of his new CD, Fresh From The Groove. The work is highly energetic and expertly mastered thanks to Grammy award producer Michael Broening, who has collaborated with the likes of George Benson, Marion Meadows, Althea Rene and Wayman Tisdale. 

Amato said he’s excited to be an instrument for the concert series.

“I have been a longtime advocate of sustainability and practice it almost every day in our household,” says Amato. “I’m not over the top or an extremist but we all need to do our part to keep our environment clean and safe.”

For more information on Dominic Amato, visit http://dominicamato.com">http://dominicamato.com/">http://dominicamato.com.

 

What: The Green Jazz Series concert featuring Dominic Amato

Where: Herberger Theater, 222 E. Monroe St., Phoenix

When: 7 p.m. Monday, April 27.

Tickets: $20 for general admission; $40 for VIP seats; $10 for ASU students with valid ID. Call the Herberger Theater box office at (602) 254-7399 or visit http://www.HerbergerTheater.org.">http://www.herbergertheater.org/">http://www.HerbergerTheater.org.

Parking and directions: http://www.HerbergerTheater.org/directions_and_parking.">http://www.herbergertheater.org/directions_and_parking">http://www.Herbe...

Information: http://www/sw-green.com">http://www/sw-green.com">http://www/sw-green.com

 

Contact:

Marshall Terrill

Information Specialist

ASU Office of Public Affairs

(602) 496-1005

Marshall.Terrill">mailto:Marshall.Terrill@asu.edu">Marshall.Terrill@asu.edu

Reporter , ASU Now

480-727-5176