Report


Big shot names at the annual International AIDS Conference held last week in Vienna, which included philanthropists Bill Gates and Bill Clinton and numerous executive directors of UN health agencies, were treated to a presentation of some exciting new findings: the first ever evidence for biological intervention against HIV-I transmission. The intervention is in the form of a vaginal gel, which contains an anti-HIV drug that reduces the chances of infection by HIV by 39% (a statistically significant reduction). The 2 1/2 year trial consisted of more than 800 women, who were asked to insert the anti-HIV gel, or a placebo, within 12 hours before or after having sex.

This new line of defense against HIV comes at the heels of two other recent major findings of preventative measures against infection. The first is behavioral: school girls and their families receiving small monthly cash payments from researchers had sex later, less often, and with fewer partners. 1 1/2 years after initiation of the payments, girls were less than half as likely to be infected with AIDS. It seems the payments, small as they were, were enough to alleviate the need for girls to have sex in exchange for cash or presents. The second preventative measure found a few years ago was physiological: circumcised men were half as likely to contract HIV. What made that story particularly successful was that many men flocked to hospitals for the procedure because of another motivation: they heard that it made sex better.

The vaginal gel results are exciting because it is the first to unambiguously lay out a medical plan of action for HIV prevention. Prior to this, more than 30 studies of microbicides, vaccines, and drugs had failed, or provided only marginal success. So this is a big step!

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As I’ve noted before, our bodies are riddled with microbes – there are more of them than there are of us (if you go by shear number). But where do they come from? Each individual has a complex ecosystem of commensal (harmless) microbes that live on our skin, in our nose, mouth, ears and gut, and we lay the foundations for this ecosystem at birth. According to a new study in the Proceedings of the National Accademy of Sciences (PNAS), different methods of birth (traditional vs cesarean section) have very different outcomes in terms of what bacteria end up colonizing you:

The goal of the present study was to obtain a community-wide perspective on the influence of delivery mode and body habitat on the neonate’s first microbiota[…] We found that in direct contrast to the highly differentiated communities of their mothers, neonates harbored bacterial communities that were undifferentiated across multiple body habitats, regardless of delivery mode. Our results also show that vaginally delivered infants acquired bacterial communities resembling their own mother’s vaginal microbiota, dominated by Lactobacillus, Prevotella,or Sneathia, and C-section infants harbored bacterial communities similar to those found on the skin surface, dominated by Staphylococcus, Corynebacterium, and Propionibacterium.

It’s been known for a long time that c-section babies were more prone to allergies and asthma, and there’s a strong link between commensals and the immune system, but exactly what the difference was remained obscure. Basically, what this paper shows is that the types of bacteria that get us started are established very early.

Babies born through the traditional route are very quickly exposes to the bacterial communities of their mothers – both vaginal and gut bacteria (women often defecate when giving birth). Once these bacteria get established, they fill up all the niches, and prevent other bacteria from getting a foothold. By contrast, c-section babies don’t have this initial exposure – the womb is fairly sterile, and the conditions of this surgery prevent contact with the mother’s other mucosal surfaces. Because of this, the infant is ripe for colonization from the myriad of bacteria found everywhere else, from the nurses and doctors that handle them to the bacteria on the skin on the mother’s breast when feeding.

It’s important to note that we can’t yet draw a distinct causative link between early establishment of bacterial communities and future disease (allergies, asthma etc), right now it’s just correlation. And though infants are colonized by very few types of microbes, as they develop, the microbial ecosystem diversifies into thousands or millions of different species. Researchers are hard at work using new technologies to try to figure out all the different things living in an adult gut (given the spiffy name, “the microbiome”), and we’ve barely scratched the surface.

The one thing that is clear is that the little things living in us and on us can have a profound effect on our health, and with new research, hopefully we can use that knowledge to our advantage.

(Note: This post is not for the squeamish)

All kinds of stuff lives in our guts. It’s been estimated that there are about ten times as many bacteria cells (microflora) in our body as human cells. Most of them are totally harmless, and indeed, they are often beneficial. But as the authors of a paper last week in Science pointed out, bacteria aren’t the only things living down there, and the beasties that live in our gut don’t always play nice, at least, not with us:

The inhabitants of the mammalian gut are not always relatively benign commensal bacteria but may also include larger and more parasitic organisms, such as worms and protozoa. At some level, all these organisms are capable of interacting with each other. We found that successful establishment of the chronically infecting parasitic nematode Trichuris muris in the large intestine of mice is dependent on microflora and coincident with modulation of the host immune response.

Trichuris is a genus of helminth worms that live in the large intestines of mammals. They are wildly successful; over 1 billion (yes, Billion) people are estimated to be infected with T. trichiuria every year. Infection starts with ingesting Trichuris eggs with your food. The eggs are able to survive the harsh environment of your stomach and make their way down to the large intestine, where they hatch and begin feeding, mating, and laying new eggs. When you defecate (we just can’t get away from poo on this blog evidently), the eggs are free to contaminate other food. If you read between the lines correctly, this means that at the beginning of the life-cycle, you must have eaten food contaminated with fecal matter (there’s a reason that this parasite doesn’t do well in regions of the world with good sanitation). This is not nearly as gross as the life-cycle of hook-worms, which can burrow into your foot, swim through your blood-stream to your lungs, then wriggle their way into your mouth through your trachea to be swallowed while you sleep – but I digress.

These researchers wondered what would trigger these ingested Trichuris eggs to hatch. If the worms hatch before they get ingested, they’ll die before they get there, and if they hatch too late, they’ll be expelled before they can establish themselves in the gut. So what is there a lot of in the location they want to hatch, that could provide a signal? Bacteria! When the researchers dumped all kinds of different bacteria on the worm eggs, they hatched. In addition, if they treated mice with high-doses of antibiotics to clear out their guts, and then fed them worm eggs, the worms didn’t hatch. Crucially, dumping bacteria on the eggs only worked if they were at body temperature (37 degrees C); at room temperature, it didn’t work. This makes sense from the worm’s perspective too – there are bacteria everywhere (especially in the poo they’re originally expelled in), but the only place there is likely to be lots of bacteria at 37 degrees is in a mammalian gut.

This doesn’t mean that we should go treating everyone in the 3rd world with antibiotics to prevent worm infections – the normal bacterial flora are too important. But it does raise some potential new lines of preventative therapy. While the exact nature of the interactions between worm egg and bacteria were not complete worked out, they did find that interactions with some types of bacteria were dependent upon a certain class of adhesion molecules, and that these interactions could be blocked by mannose. More understanding of how these different inhabitants of our intestines communicate at the molecular level will doubtless lead to great therapies, but as most of these infections happen in the third world, those therapies will have to be cheap if they’re to do any good.

Although I studied physics and chemistry in college, I have always held an inherent appreciation for how life works.  And now, researching microbes in action, I am continually amazed by their diverse habitats and metabolisms.  It is remarkable to think how despite the diminutive size of microbes, they are dominant members of our biosphere and play a key role in every known biogeochemical cycle.  This list includes carbon, sulfur, nitrogen, and oxygen as well as trace metals such as iron, cobalt and zinc.  I have started thinking that if there is an available compound on Earth, then microbes have found a way to use it.

What does it mean that microbes are involved in these biogeochemical cycles?  It usually implies that a microbial species has found a way to use a form of that specific element while the microbe undergoes cellular respiration.  Although respiration is complex, I tend to think of it in a simplified manner as a transport of electrons from one compound to another by a living organism.  The organism utilizes this electron transport to produce energy in order for it to stay alive and reproduce.  As humans, we take electrons from the carbon compounds we consume as food and transport those electrons to the oxygen we breathe.  Since we use oxygen, this is aerobic respiration. One can think of the food we eat as electron donors and oxygen as the electron acceptor.  Now, a fascinating aspect about microbes is that different species have evolved to use a variety of electron donors and acceptors in respiration process.  Not only is this how microbes are involved in Earth’s biogeochemical cycles, but this is why certain microbes can be found in such extreme conditions, such as hydrothermal vents which have been discussed earlier.

Since microbes can use a variety of compounds as electron acceptors, what if there was a way to harness these electrons to produce electricity?  In 1911, M.C. Potter was reported to be the first person to observe electricity production from microbes but it has only been within the past 30 years that this research has gained momentum.  In these systems, which are called microbial fuel cells, the material the microbes are using as an electron acceptor is called an electrode, more specifically an anode. By connecting the anode with a metal wire to a region with even higher electron affinity, termed a cathode, we can generate a circuit.  Oxygen is one of the best electron acceptors and typically these systems have oxygen present near the cathode and the microbes grow in an chamber without oxygen in order for electrons to flow from the anode to the cathode.

Personally, I find the mechanism for microbes to transport electrons to a solid surface fascinating as a basic science question and think that understanding this process better would shed some light on how microbes do this in nature.  Right now, there are a handful of microbes known to utilize a solid surface as an electron acceptor and I am curious about what others are out there that have not yet been identified.  What do these different species have in common?  What influences growth and thus electron generation?  How is the structure of the microbes growing on the anode as a biofilm influenced by the anode properties, such as material composition or surface patterning?  How does the internal properties within the biofilm correspond to electron generation, such as pH?  To address these questions, I perceive microbial fuel cells as a useful system to explore how microbes form biofilms on surfaces that act as an electron acceptor.

Further, as a new area of research with potentially huge contributions to be made more knowledge will improve how this mechanism is utilized in technology not only for energy production but also for organic waste removal.  An attractive aspect of this technology is that electricity generation by the microbes goes hand-in-hand with organic waste removal because the microbes use the organic compounds as their electron donors, or food.  In wastewater treatment, this would allow for the water to become purified at the same time electricity is generated.  Electricity production is still quite low with one report stating that their microbial fuel cell design could power 16 60-watt light bulbs.  There is still room for improvement in power generation and I believe that addressing the mechanistic questions about microbial electron transport to an outside electron acceptor will aid in both improving our basis for building these technologies and our understanding of how our microbes are major players in our world’s biogeochemical cycles.

As I wrote earlier, scientists have a bit of a PR problem in communicating their science to the public. In the most recent issue of Nature, Naomi Oreskes and Erick Conway highlight the problem with respect to climate change (sorry, it’s behind a paywall, but I will quote them at length):

[…] opinion polls have repeatedly shown that large numbers of US citizens — and many in Canada, Australia and some parts of Europe — disbelieve the scientific conclusions. A December 2009 Angus Reid poll found that only 44% of Americans agreed that “global warming is a fact and is mostly caused by emissions from vehicles and industrial facilities”. There has been essentially no change in public acceptance of the scientific conclusions since the 1980s, with the public continually muddling the facts — believing, for example, that the ozone hole is the main cause of climate change.

In a recent book, these same authors showed how much of this public doubt was sewn in the later part of the 20th century by a few right-wing scientists who also worked to obscure the connection between tobacco and cancer and between CFC’s and ozone depletion.

What is particularly important to understand is how the industry used the trappings of science to make its case. It created the Council for Tobacco Research (originally the Tobacco Industry Research Council, but it dropped ‘industry’ on advice from a public-relations firm), along with various newsletters, journals and institutes, to publish claims. And it recruited scientists to speak up for this work, because it was obvious that tobacco-industry executives would lack credibility — although often the scientists had little or no expertise in medicine, oncology or epidemiology.

This strategy of creating a ‘scientific Potemkin village’ was applied to global warming too. During the period that we scrutinize in our book, the Marshall Institute didn’t create its own journal, but it did produce reports with the trappings of scientific argument — such as graphs, charts and references — that were not published in the independent peer-reviewed literature. At least one of these reports — read and taken seriously by the administration of former US president George H. W. Bush — misrepresented the science by presenting only part of the story. NASA climate modeller James Hansen and his team had demonstrated in the peer-reviewed literature that historic temperature records could be best explained by a combination of solar irradiance, volcanic dust, and anthropogenic greenhouse gases. The Marshall Institute report included only a single piece of Hansen’s graph, using the fragment to make it seem as if there was a poor link between carbon dioxide and climate warming, and to argue — against Hansen’s analysis — that the real culprit was the Sun.

Of greatest interest to me, however, was the identification of several of the problems scientists have in combating this type of approach.

One reason that the public is confused is that people have been trying to confuse them, in large part by intentionally waging campaigns of doubt against climate science. Doubt-mongering is an old strategy. It works because if people think the science is contentious, they are unlikely to support public policies that rely on that science[…]

[Those scientists] who engage in discussion discover a frustrating situation. Whatever facts one supplies, the sceptics continue to challenge them or offer alternative explanations. One cannot call one’s opponent a liar because it just seems desperate and ad hominem. Nor does it work to debate their points, because that feeds into the ‘controversy’ framework: the sceptics say there is a debate, you say there isn’t — voilà, they have proved their point.

The authors also point out some suggestions, some of which I agree with whole-heartedly, and others that are a bit more complicated:

For too long, the scientific community has subscribed to the idea that the ‘real work’ of science takes place in the lab or in the field, and that taking the time to communicate broadly doesn’t count. This assumption needs to be rethought, and the academic reward systems changed to encourage outreach. Contrarians do take the time and, given their tiny numbers, have had an enormous effect. In the nineteenth and early twentieth centuries it was much more common for scientists to write books aimed at the educated public; this tradition could be revived.

No argument here. Right now, tenure, promotion and pay grade at large research universities are largely based on grants and peer-reviewed publications. Having a few positions that are dedicated to public outreach, and are based on popular science publications and community education would be invaluble.

Scientists have much to learn about making their messages clearer. Honesty and objectivity are cardinal values in science, which leads scientists to be admirably frank about the ambiguities and uncertainties in their enterprise. But these values also frequently lead scientists to begin with caveats — outlining what they don’t know before proceeding to what they do — a classic example of what journalists call ‘burying the lead’.

A few weeks ago, 255 members of the US National Academy of Sciences wrote a letter in response to recent attacks on climate scientists. The Academicians began by noting that “science never absolutely proves anything”, and went on to explain that “when some conclusions have been thoroughly and deeply tested, questioned, and examined, they gain the status of ‘well-established theories’ and are often spoken of as ‘facts’”. Although this care and nuance is intellectually scrupulous and admirable, being so philosophical about the ‘factual’ nature of climate change doesn’t serve public communication.

This reminds me of the “just a theory” argument of evolution-deniers. The way that scientists use the word “theory” and the way that scientists use the word “theory” are drastically different, and this was deliberately used by the opposition to obscure the solid state of the fact of evolution. As a scientist, I do have qualms about over-stating certainty, but at the same time, I recognize that we need to speak differently to a general audience than we do with our scientific peers. I don’t mean talking down to the public, but rather changing our vocabulary so that we’re actually communicating what we intend to communicate.

The authors also make several other good points about scientists knowing their history and journalists stating their sources (often the “experts” on the anti-science side are scientists but in completely unrelated fields), but unfortunately, these are suggestions for when we’re called to debate, which is something we want to avoid anyway.

The article ends on a simultaneously optimistic and ominous note, and I’ll leave you with that

Of the many cases of doubt-mongering that we have studied, most ended for the better. At a certain point, the companies manufacturing chlorofluorocarbons (CFCs), admitted their link to ozone depletion and did the right thing by committing to phasing them out. The public is now firmly convinced of the link between cigarettes and cancer. Inductive reasoning implies that the same should happen with climate change: the consensus scientific view will eventually win public opinion. But in the meantime irreversible damage is being done — to the planet, and to the credibility of science.

A group of American and Canadian scientists (primarily based at McGill) published a paper recently in the journal of the International Society of Microbial Ecology (ISME) that offers insight into the possibility of life on Mars.  The paper is entitled “Microbial characterization of a subzero, hypersaline, methane seep in the Canadian High Arctic”, and you can read the abstract here.  The researchers found a spring that is below freezing, but liquid due to the high salinity (24%, for comparison the ocean is about 3.5%).  They found methane seeping out of this spring.  Methane seeps like this are extremely rare in the terrestrial world, but have been relatively well studied in the ocean.

In their words : “Here we report on the first microbiological and geochemical characterization of the only known terrestrial methane seep in a cryo-environment on Earth in the form of the hypersaline subzero spring, which arises through thick extensive permafrost in an area with an average annual air temperature of -15 °C and with air temperatures below -40 °C common during the winter months.  This site provides a model of how a methane seem can form in a hypersaline cryo-environment and can support a viable microbial community where methane itself may behave as an energy and carbon source for sustaining anaerobic oxidation of methane.”

Typically when methane is being produced it is either through biological or geological processes.  The recent discovery of methane plumes on Mars was exciting for this reason… it implied that either there was some unknown geologic activity on Mars (it is assumed to be inactive below the surface) or there was a community of microbes producing methane on Mars.  That is a maybe bit of an oversimplification, but I am not a planetary geologist.  Anyhow, folks in the astrobiology world have been proposing that we might be looking at evidence of methane producing microbes (methanogens) on Mars.  Other astrobiologists disagree with this contention because while there is water on Mars, it is very saline… so saline that some think life is impossible (technically it is the water activity and not the salinity that make the planet so inhospitable, but sanity is a good way to thing about it).  Two of the things that make this recent paper so cool is that it finds a location on Earth that could be analogous to the hyper-saline methane seeps on Mars, and that it provides evidence for an alternate scenario to methanogens being what we should expect to find if there is life on Mars.

The methane in the spring in this study is not likely to be produced biologically.  The difference between the carbon isotopes in the methane and the carbon dioxide indicate that it is not biological in origin (organisms preferentially use certain isotopes, and therefore leave an isotopic “signature” in the carbon that indicates when methane was formed biologically).  However, the scientists found a community of organisms living in this ultra-extreme environment.  The organisms they found (both bacteria and archaea) seem to be using the methane as energy and a carbon source, rather than producing it.  These metabolisms might be coupled with sulfur oxidation like it is at deep-sea hydrothermal vents and methane seeps.  Microbes that “eat” methane are interesting from a climate change point of view because methane is one of the major greenhouse gasses aside from carbon dioxide.

The archaea found in this study are related to those found in hypersaline deep-sea methane seep sediments, while the bacteria seemed to be related to those found in terrestrial Arctic and Antarctic environments.  Another cool thing about this paper is that the authors were able to culture 8 different types of bacteria from these samples.  This is exciting because more than 99% of all bacteria have not yet been cultured, and scientists can learn a great deal more about an organims once they are able to grow it in a lab.

The authors also suggest that this site might be a location where ancient DNA could be preserved.  This is because high salt tends to keep DNA from degrading over long periods of time.

In summary this study is very cool because…

  • It characterizes life from an extreme environment that has not been studied previously (terrestrial hypersaline methane seep).
  • It offers insight into what type of life we might expect to find in similar environments on Mars (not necessarily what we expected).
  • The authors were able to extract DNA from difficult samples, and was able to culture organisms from this extreme environment.
  • It suggests that this site might offer more cool discoveries in the future (like ancient DNA).
  • It draws a connection between the microbial ecology of the hot deep sea and the frigid Arctic.

I would like to introduce myself as a new contributor to this blog.  I study deep sea hydrothermal vent microbes.  This might sound incredibly obscure, but I think it is ridiculously cool, and most of the time I can convince myself that it is important too.  My field of study overlaps with the quest to understand the evolution of life on this planet, the search for life elsewhere in the solar system, the race to discover and describe the inhabitants of this planet, and maybe even climate change. There is some evidence suggesting that life on Earth may have evolved in heated environments such as hydrothermal vents. Astrobiologists searching for life on other planets believe that geologic environments similar to hydrothermal vents may exists on planetary bodies such asEuropa and may harbor life. It is now known that there is more biomass (dry weight of living things) in deep sea microbes than on all the continents combined, and we have virtually no idea what impact these organisms have on ocean chemistry.

Hydrothermal Vents are areas of the sea floor where the nature of the rock allows water in the interstices of the ocean crust heated by Earth’s internal fire to spew into the ocean and interact with the colder rocks and water that it encounters.  The water that comes in contact with the magma becomes super-heated and is therefore able to dissolve lots of minerals that water doesn’t otherwise contain.  Heat adds energy to a system that causes chemical reactions to speed up, and so many reactions happen in the presence of hot water that wouldn’t be noticeable otherwise.  These hydrothermal fluids can be up to 350oC (662oF), which means that they would be gas (water vapor) under the pressures that we are used to on Earth’s surface.  However, pressures at the sea floor bottom can be up to 345 times what they are at sea level, so these liquids remain just that.  As soon as the heated fluid comes in contact with cold seawater (2oC, 36oF), the dissolved minerals immediately crystallize out of solution and form magnificent solid rock chimney-like structures that are given names like HulkGiraffe, or Pinocchio by the scientists who discover them.

Deep sea environments are very challenging to study because we can’t see them.  The Hubble space telescope can see galaxies 15 billion light years away, but satellites cannot take pictures of the bottom of the ocean because the water itself acts a barrier to light beyond 50 meters.  We have ways of sensing the topography of the ocean floor using satellites and sonar aboard ships, but we cannot see what’s there without sending down some type of camera with its own light source.  So while there are many snapshots of the deep, scientists have to make educated guesses about what lies between. We have more detailed maps of the surfaces of the Moon and Mars than we do of the sea floor.  I have described the challenges of studying the mysterious ocean hereThis blog is another great resource for everything deep.

In 1977 geologists made a discovery that changed the way we think about life on this planet.  During a geologic research cruise to find places on the sea floor where Earth’s crust was pulling apart geologists found unbelievable assemblages of species.  In this environment, thought to be devoid of life due to the lack of sunlight, they found diversity and richness that rivaled the tropical rain forests.  This was contradictory to everything scientists thought they understood about the deep sea.  There had been previous indications of life in these deep wastelands, but no one expected that a significant amount of life could thrive in the deep.  It had been assumed that there simply couldn’t be enough organic matter drifting down from above to support dense communities. A fundamentally new process for energy generation had to exist to allow these communities to flourish.  Geology was the key!  These perplexing organisms were tapping into energy from inside the earth, rather than 93 million miles away from it, through a process called chemosynthesis (as opposed to photosynthesis) that was completely unknown for the first 10,000 years of human civilization.   My expanded description of this incredible discovery can be found here.

My research focuses on the fundamental unanswered questions of which microbes are living in the vent chimneys, patterns in their distribution, and what, chemically, are they doing.  Do their metabolisms affect the global carbon cycle?  Do the ecological patterns of species richness and distribution mirror the well-established ecological patterns of larger organisms?  What allows these organisms to live at higher temperatures than most other organisms on the planet?  These are some of the questions that I hope my research will help answer one day.  I would like to introduce myself as a new contributor to this blog. I study deep sea hydrothermal vent microbes.  This might sound incredibly obscure, but I think it is ridiculously cool, and most of the time I can convince myself that it is important too.  My field of study overlaps with the quest to understand the evolution of life on this planet, the search for life elsewhere in the solar system, the race to discover and describe the inhabitants of this planet, and maybe even climate change. There is some evidence suggesting that life on Earth may have evolved in heated environments such as hydrothermal vents. Astrobiologists searching for life on other planets believe that geologic environments similar to hydrothermal vents may exists on planetary bodies such as Europa and may harbor life. It is now known that there is more biomass (dry weight of living things) in deep sea microbes than on all the continents combined, and we have virtually no idea what impact these organisms have on ocean chemistry.

Hydrothermal Vents are areas of the sea floor where the nature of the rock allows water in the interstices of the ocean crust heated by Earth’s internal fire to spew into the ocean and interact with the colder rocks and water that it encounters.  The water that comes in contact with the magma becomes super-heated and is therefore able to dissolve lots of minerals that water doesn’t otherwise contain.  Heat adds energy to a system that causes chemical reactions to speed up, and so many reactions happen in the presence of hot water that wouldn’t be noticeable otherwise.  These hydrothermal fluids can be up to 350oC (662oF), which means that they would be gas (water vapor) under the pressures that we are used to on Earth’s surface.  However, pressures at the sea floor bottom can be up to 345 times what they are at sea level, so these liquids remain just that.  As soon as the heated fluid comes in contact with cold seawater (2oC, 36oF), the dissolved minerals immediately crystallize out of solution and form magnificent solid rock chimney-like structures that are given names likeHulkGiraffe, or Pinocchio by the scientists who discover them.

Deep sea environments are very challenging to study because we can’t see them.  The Hubble space telescope can see galaxies 15 billion light years away, but satellites cannot take pictures of the bottom of the ocean because the water itself acts a barrier to light beyond 50 meters.  We have ways of sensing the topography of the ocean floor using satellites and sonar aboard ships, but we cannot see what’s there without sending down some type of camera with its own light source.  So while there are many snapshots of the deep, scientists have to make educated guesses about what lies between. We have more detailed maps of the surfaces of the Moon and Mars than we do of the sea floor.  I have described the challenges of studying the mysterious ocean hereThis blog is another great resource for everything deep.

In 1977 geologists made a discovery that changed the way we think about life on this planet.  During a geologic research cruise to find places on the sea floor where Earth’s crust was pulling apart geologists found unbelievable assemblages of species.  In this environment, thought to be devoid of life due to the lack of sunlight, they found diversity and richness that rivaled the tropical rain forests.  This was contradictory to everything scientists thought they understood about the deep sea.  There had been previous indications of life in these deep wastelands, but no one expected that a significant amount of life could thrive in the deep.  It had been assumed that there simply couldn’t be enough organic matter drifting down from above to support dense communities. A fundamentally new process for energy generation had to exist to allow these communities to flourish.  Geology was the key!  These perplexing organisms were tapping into energy from inside the earth, rather than 93 million miles away from it, through a process called chemosynthesis (as opposed to photosynthesis) that was completely unknown for the first 10,000 years of human civilization.   My expanded description of this incredible discovery can be found here.

My research focuses on the fundamental unanswered questions of which microbes are living in the vent chimneys, patterns in their distribution, and what, chemically, are they doing.  Do their metabolisms affect the global carbon cycle?  Do the ecological patterns of species richness and distribution mirror the well-established ecological patterns of larger organisms?  What allows these organisms to live at higher temperatures than most other organisms on the planet?  These are some of the questions that I hope my research will help answer one day.

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