Life Essay, Research Paper

Until recently, scientists believed that the sole source of

energy responsible for life on earth was the sun. In 1977, a

group of scientists researching the theory of plate tectonics,

traveled to the floor of the equatorial Pacific Ocean and

discovered something that could possibly explain how life

began on this planet. From the Galapagos Rift’s thermal

springs, scientists discovered densely populated communities of

several species never before observed. Since that time the

Federal Government has devoted more than 10 million dollars

to research these communities and their evolutionary history.

This figure, to many scientist’s dismay, is dramatically less

than that of the space exploration program’s budget. For

example, in 1992, the government budget for oceanography

research was $600 million while NASA spent 8.5 billion. We know

more about the space around us than we do about our own

home. Only 1 percent of the sea floor has been mapped. The sea

is the largest, most inaccessible, and least understood

ecosystem on this planet.

Since studies of these communities began, previous notions

that cold darkness, and extreme pressure are inimical to life

have been disproved. We now know that an ecosystem can be

sustained by unusual energy sources. The animals that have

been discovered in hydrothermal vents are fascinating as well

as extremely important. The structure of these creatures is

such that a new kingdom has been discovered/created.

Previously scientists divided the living world into two

kingdoms: bacteria, also known as prokaryote and

eukaryotes (plants and animals). The difference between the

two kingdoms was their genetics. The DNA of these newly

discovered animals was distinct from the two other kingdoms.

They have been called archaea. Research on these animals is

limited since they do not grow and culture well in a

laboratory. These animals live in extremely hot temperatures

of 160 degrees Fahrenheit and higher, while microbes have been

found living in boiling water. This revelation surely must

change all of the "rules" we have for health standards. These

newly discovered facts must dramatically change the way we

think of life on earth.

Living in these vents are entire communities of

invertebrates: tube worms, mussels, clams, and even shrimp. In

the absence of light and without the photosynthesizing

plankton that provide most sea life with food, these animals

have an alternate way to live. These invertebrates have

formed symbiotic relationships with the bacteria living with

them. The mechanics of this relationship are incredibly

interesting. Bacteria thrive on sulfide which is found in vent

water (hydrogen sulfide). They use the sulfide’s chemical energy

to produce organic carbon compounds similar to how plants

use solar energy in photosynthesis. The bacteria employ

chemical rather than light energy to transform inorganic

carbon to organic compounds. This process is called

chemosynthesis, and was at first thought to be a rare

phenomenon. The invertebrate houses the bacteria and

provides chemicals needed for the process of chemosynthesis.

The bacteria in turn gives organic carbon compounds to the

invertebrate, which keeps the invertebrate alive, (so it expends

little or no energy gathering its own food). An example of this

type of tubeworm can be found in vents along submarine

mountain ranges off of the western coasts of Mexico and

South America. One in particular, at a site called the Rose

Garden in the Galapagos Rift is long and white with a luminous

red plume. Upon examination it was discovered that these

worms have no mouth, stomach, or digestive system. They

survive by extending their plume into the vent fluids absorbing

numerous compounds including sulfide which are turned over

to the bacteria. The bacteria then provide food to their host.

The existence of this symbiotic relationship between an

invertebrate and a bacteria is as incredible as their existence.

Another feature of this relationship is their mutual dependence

on oxygen. Oxygen is an element required by the vent bacteria

to perform its essential role. Interestingly, this is one of the

few ways these communities are tied to the world away from

the vent.

The implications of this awesome discovery are providing

us with leads, clues, and suggestions to where life began and

where it is going. From biotechnology that can be used in

tracing fingerprints in a crime scene, to discovering where life

begun, this great new breakthrough will immensely enhance

our understanding and comprehension of our life and our

environment. We do not yet know where this new information

will lead us, as our knowledge as well as our funding and

perhaps even our imagination is limited. We once thought the

earth was flat, ancient man thought that lightning was from

an angry g-d, and until recently scientists thought that life

without sunlight at the bottom of the ocean was impossible, so

we are left with an incredibly complex universe to study,

starting with our planet.

REFERENCES

"Clues to Fiery Origin of LIfe Sought in Hothouse MIcrobes"

by William J. Broad The New York Times May 09, 1995 V144,

pB7(N), pC1(L), col 5, (48 col in.).

"Depths of Ignorance" by Cindy Lee Van Dover. Discover

September 1993 V14, n9, p. 37(3).

"Hydrothermal-Vent Communities of the Deep Sea" by

Verena Tunnicliffe

American Scientist July/August 1992 V80, n4, p.336(14).