The first field, known as the Lost City, was discovered on the sea floor Atlantis Massif mountain in the mid-Atlantic. The vents are formed by a process known as serpentinization. Seabed rock, in particular olivine magnesium iron silicate reacts with water and produces large volumes of hydrogen. This mirrors the way that cells harness energy. Cells maintain a proton gradient by pumping protons across a membrane to create a charge differential from inside to outside. Known as the proton-motive force, this can be equated to a difference of about 3 pH units.
This energy, along with catalytic iron nickel sulfide minerals, allowed the reduction of carbon dioxide and production of organic molecules, then self-replicating molecules, and eventually true cells with their own membranes. Chemist Laura Barge, also a research scientist at JPL, is testing this theory using chemical gardens — an experiment you might have carried out at school.
The classical chemical garden is formed by adding metal salts to a reactive sodium silicate solution. The metal and silicate anions precipitate to form a gelatinous colloidal semi-permeable membrane enclosing the metal salt. This sets up a concentration gradient which provides the impetus for the growth of hollow plant-like columns.
Chemical gardens in the lab mimic the conditions of hydrothermal vents and are a useful model for studying how life could have started.
To mimic the early ocean she has injected alkaline solutions into iron-rich acidic solutions, making iron hydroxide and iron sulfide chimneys. From these experiments her team have illustrated that they can generate electricity: just under a volt from four gardens, but enough to power an LED, 3 showing that the sort of proton gradients that provide energy in deep sea vents can be replicated.
Nick Lane, a biochemist at University College London in the UK, has also been trying to recreate prebiotic geo-electrochemical systems with his origins of life reactor. Lane has been persuaded by how closely the geochemistry and biochemistry align. For example, minerals such as greigite Fe 3 S 4 are found inside vents and they show some relationships to the iron—sulfur clusters found in microbial enzymes. They could have acted as primitive enzymes for the reduction of carbon dioxide with hydrogen and the formation of organic molecules.
On one side of a semiconducting iron—nickel—sulfur catalytic barrier, an alkaline fluid is pumped through to simulate vent fluids and on the other side, an acidic solution that simulates sea water.
As well as flow rates, the temperatures can be varied on both sides. They are working on replicating their results and proving that the formaldehyde seen is not coming from another source such as degradation of tubing. From the same conditions, Lane says they have also been able to synthesise low yields of sugars, including 0. Investigating hydrothermal vents, geochemist Frieder Klein from Woods Hole Oceanographic Institution in the US has discovered a variation on the deep sea origin story.
He has found evidence of life in rock below the sea floor which might have provided the right environment for life to start. The Lost City Field is an alkaline deep sea vent found on the sea floor Atlantis Massif mountain in the mid-Atlantic in Klein and colleagues were looking at samples from cores drilled from the Iberian continental margin off the coast of Spain and Portugal in The samples came from rock m below the current sea floor, which would have been 65m below the early unsedimented ocean floor.
He saw some unusual looking veins in the samples, composed of minerals also found at the Lost City hydrothermal system. This suggests similar chemistry could be going on below the sea floor. He suggests the desiccating properties of the mineral brucite Mg OH 2 might explain the preservation of organic molecules from the microbes.
These included amino acids, proteins and lipids which were identified by confocal Raman spectroscopy. Klein says he was initially sceptical, but analysis of extracted samples confirmed unique lipid biomarkers for sulfate-reducing bacteria and archaea, which are also found in the Lost City hydrothermal vents system.
This process of photosynthesis sustains much of life on Earth including humans , and is responsible for most of Earth's primary production , the amount of organic carbon produced by photosynthetic organisms normally, but see below in a given habitat area and time. Sunlight rarely penetrates deeper than m in oceanic waters, beneath which photosynthesis cannot occur.
Instead, animals depend upon nutrients that sink down as debris. All this makes for a vast, inhospitable environment. In fact, until quite recently, scientists assumed life could not survive in the deep. In the s, technical advances in deep-sea exploration e. The discovery of these hydrothermal vents demonstrated that animals were thriving without sunlight under some of the most extreme conditions described on Earth.
Deep-ocean hydrothermal vents occur where there is intense volcanic activity. Seawater permeates rock, heats up and becomes enriched with substances from the rock, like metals, sulfide, dihydrogen, and methane.
Mineral-rich chimneys, around which hydrothermal-vent animals live, then form when these heated fluids exit the seafloor Figure 1. During the s, scientists realized that these habitats supported an unusual type of primary production, fueled not by sunlight and photosynthesis, but by energy from reactions between chemicals found in the hydrothermal fluid, like sulfide, and the oxygen present in seawater.
Amazingly, some basic, single-celled microorganisms can use this energy to build the parts of their one cell. Hydrothermal vents provided the first evidence that this process, called chemosynthesis , could sustain so much life in otherwise desert-like surroundings.
But what about the larger animals that live in these environments? How do they get the energy they need to survive? Well, many of these animals acquire their energy by maintaining close relationships with chemosynthetic bacteria.
This type of relationship, where two different organisms live together closely is called symbiosis. In chemosynthetic symbioses, both organisms involved are believed to benefit from the relationship. The larger organism is called the host and the smaller organism, the bacterium in this case, is called the symbiont. The bacteria live in specialized organs within their hosts, and their primary production provides the host with energy.
In exchange, the host furnishes its bacteria with shelter and essential compounds. Examples of animal at hydrothermal vents that harness symbioses include giant tubeworms and bivalve clams Figures 1 , 2. In , similar symbioses were described in animals living around fluids seeping from seafloor sediments rich in sulfide and methane, found in the Gulf of Mexico.
These areas are different from hydrothermal vents and are called cold seeps , because the temperature of the seeping fluids is close to that of bottom seawater. Cold seeps are caused by the decay of plant and animal matter that has accumulated on the sea floor, buried under sediment. Other sulfide- and methane-rich deep-sea habitats Figure 3 , such as decaying wood falls or large carcasses, sustain similar but smaller-sized organisms.
Symbioses allow all these organisms to thrive in the deep sea. Among the most remarkable of these animals that can survive in the deep sea are bathymodioline mussels. These mussels are in the same family as edible mussels, but the Bathymodiolinae have become specialized for living in deep-sea environments over the last 60 million years. Various species are found worldwide, with shell lengths from 2 mm the size of a sesame seed to 40 cm the size of a laptop screen Figure 2.
Bathymodioline mussels can carpet hundreds of square meters of seafloor Figure 1 , often as a large component of hydrothermal-vent and cold-seep communities, yet they generally are not found anywhere else in the ocean.
In the past, bringing such samples to the surface resulted in loss of the gaseous portion. WHOI scientists and engineers developed the IGTS to keep samples of vent fluid at high pressure until they can be brought to a lab for analysis. WHOI geologist Chris German led the expedition, which visited the deepest known hydrothermal vents in the world. The test being used to diagnose the novel coronavirus—and other pandemics like AIDS and SARS—was developed with the help of an enzyme isolated from a microbe found in marine hydrothermal vents as well as freshwater hot springs.
This digital photo essay brings you the forms, figures, and facts of life more than a mile and half deep. At hydrothermal vents there are body-snatchers, intestinal hitchhikers, and chest-bursters, but something about them is still alluring to Lauren Dykman. Some of the most complex insights in marine science are no match for the communicative power of art.
Check out these five recent collaborations between ocean scientists and artists. The Curious Names of Deep-sea Features The story black smoker chimney resembles a monster on the seafloor, with hot fluids….
In the winter of , Expedition 15 ventured into the Pacific Ocean to examine life in some of the most extreme environments on Earth—deep-sea hydrothermal vents. January 6 to 27, Join researchers as they study the biology, geology, and chemistry of some of the deepest hydrothermal vents on Earth.
October 7 to November 6, Follow researchers as they explore one of the deepest points in the Caribbean Sea, searching for life in extreme seafloor environments. The 5th Elisabeth and Henry Morss Jr. He uses techniques that span isotope geochemistry, next generation DNA sequencing, and satellite tagging to study the ecology of a wide variety of ocean species.
He recently discovered that blue sharks use warm water ocean tunnels, or eddies, to dive to the ocean twilight zone, where they forage in nutrient-rich waters hundreds of meters down.
Born in New Zealand, Simon received his B. With much of his work in the South Pacific and Caribbean, Simon has been on many cruises, logging 1, hours of scuba diving and hours in tropical environs. He has been a scientist at Woods Hole Oceanographic Institution since Gregory Skomal is an accomplished marine biologist, underwater explorer, photographer, and author. He has been a fisheries scientist with the Massachusetts Division of Marine Fisheries since and currently heads up the Massachusetts Shark Research Program.
For more than 30 years, Greg has been actively involved in the study of life history, ecology, and physiology of sharks. His shark research has spanned the globe from the frigid waters of the Arctic Circle to coral reefs in the tropical Central Pacific. Much of his current research centers on the use of acoustic telemetry and satellite-based tagging technology to study the ecology and behavior of sharks.
He has written dozens of scientific research papers and has appeared in a number of film and television documentaries, including programs for National Geographic, Discovery Channel, BBC, and numerous television networks.
His most recent book, The Shark Handbook, is a must buy for all shark enthusiasts. Robert D. He served in the U. Navy for more than 30 years and continues to work with the Office of Naval Research.
A pioneer in the development of deep-sea submersibles and remotely operated vehicle systems, he has taken part in more than deep-sea expeditions.
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