By Victoria Tarasova
Hydrothermal vents in the depths of the ominous sea continuously spew super-hot, mineral-rich water that helps support a diverse, fascinating array of life. As gigantic plates along the Earth’s crust move apart, crevices form in the ocean floor. Water seeps in through the cracks and is heated by magma below the surface. As it reaches temperatures in excess of 400°C, it is released by the vents as underwater steam. The microbes at these sites heavily depend on gases (such as sulfur and methane) that are contained within these bursts of water. In fact, until recently, scientists believed that all forms of life in this ecosystem disappeared when thermal currents were absent.
However, a new study reveals that new microbes supplant the active hydrothermal vent’s microbes after the site ceases to produce thermal energy. These new microbes are able to live in an entirely heat-free environment. They directly feed off the solid iron and sulfur deposits that compose the vents, which are void of the nutrient-rich water their predecessors required to thrive.
According to USC graduate researcher Jason Sylvan, the next step in the research process is to analyze samples of the vents from different years. This analysis will help determine the process by which the second generation of microbes is capable of developing in the barren and dormant vents.
The discovery of ecological succession in hydrothermal vents raises several other important research questions.
Hydrothermal vents are known to be ephemeral in existence, relying on the movement of tectonic plates and volcanic activity in order to generate their own steam and thermal energy. Since the sites shift frequently, there are potentially numerous dormant vents where other forms of iron-dependent microbes may exist.
The new microbes may also differ from their predecessors in their ability to thrive in highly acidic environments. Hydrothermal vents generate CO2, which contributes to ocean acidification by forming carbonic acid in water.
Additionally, the researchers are interested in determining if these microbes are able to live beneath rock surfaces and other extreme environments.
Forest ecosystems are able to gradually replenish themselves after being destroyed by massive forest fires. This phenomenon, known as ecological succession, whereby there are changes in the composition or structure of a community, is well documented among plant and animal species. Though more research is necessary to fully understand the regeneration process in the dormant hydrothermal vents, the study provides an additional platform for ecologists to explore how ecosystems recover from natural unbalances and how species adapt to severe changes in temperature, acidity, and chemical composition.
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CERC provides a course on concepts of biological evolution, from pre-Darwinian attempts to describe life through modern genetic theory. It emphasizes the history of evolutionary thought and science, reviews the basic principles of evolutionary theory, and discusses their implications for modern life as well as state-of-the art technologies, such as genomics. Topics covered include natural selection, types of fitness and variation, speciation, reproduction and the transfer of genetic traits, the structure of DNA and a look at evolution over the long term via introductory systematics.
This course is part of CERC’s Certificate Program in Conservation and Environmental Sustainability. Courses may be taken on an individual basis or you may pursue the full 12-course Certificate. Interested in learning more? Visit our website or contact CERC for more information: cerc@columbia.edu or 212-854-0149.
Victoria Tarasova is an intern at the Center for Environmental Research and Conservation.
