Tiny creatures hold big secrets
The humble microbe provides the planet with oxygen and helps combat global warming.india Updated: Sep 28, 2005 15:19 IST
Meet the smallest creature in the world's oceans: the humble microbe.
It provides the planet with oxygen and helps combat global warming. A staggering number of the single-celled organisms live in the oceans which cover two-thirds of the globe, yet not enough is known about the role they play in the planet's health.
An international team of marine scientists has started confronting the mammoth challenge of cataloguing and exploring the biodiversity of the marine microbe as part of a $1 billion, 10-year "Census of Marine Life" project.
The first global effort to map marine species involves hundreds of scientists in more than 70 countries.
The sub-project "International Census of Marine Microbes", led by Dutch and US scientists, aims to lay out what is known, what is not known and what may never be found out about the oceans' micro-organisms and their viruses.
"Microbes control bio-chemical cycles in the world vital for life, and most of it is done by marine microbes. But we have no clue how many there are, how many types, how they are spread," said Lucas Stal, project member and microbiologist at the Netherlands Institute of Ecology.
"There are tremendous changes happening in the environment but nobody really knows where it all is going. And the reason is that we don't know how major eco-systems such as oceans work," Stal told Reuters.
"We send space shuttles to the moon and Mars but we know so little about our own planet."
Stal's institute, the US Marine Biological Laboratory (MBL) and the Royal Netherlands Institute of Sea Research are co-ordinating the project, which also includes scientists from Germany, Spain, France and Japan.
Microbes that rule the world
For more than 3 billion years, microbes have mediated critical processes that allowed higher organisms to evolve. These creatures dominate the Earth's biodiversity particularly in oceans, where they account for 90 per cent of the biomass.
Scientists estimate that there are about 1 million bacteria and 10 million viruses per millilitre of ocean water, and about 1 billion bacteria per gram of sediment.
"Although they are largely invisible to the naked eye, micro-organisms are pervasive in all environments and have a profound impact on Earth's habitability and biodiversity," said Mitchell Sogin, director of MBL.
Marine microbes influence climate and play an essential role in maintaining the planet's oxygen and carbon balance.
Carbon dioxide - the greenhouse gas produced mainly by burning fossil fuels which is blamed for worsening global warming - is absorbed by ocean microbes, providing a counterbalance to global warming.
However, only a few hundred species of the carbon dioxide-drawing marine microbes have been described so far and scientists do not know how long the process will continue.
Scientists also discovered that some marine microbes limit global warming by consuming methane - another greenhouse gas, the concentration of which is rising because of human activity.
Microbes also supply the greater part of the planet's breathable oxygen, with algae and other tiny organisms in the seas releasing about 150 billion kg of oxygen every year.
But despite their crucial role, marine microbes - one-tenth the diameter of human hair - have been largely ignored.
"We want to convince the human community to make a commitment to address the questions about marine microbes, just like huge efforts are committed to space research," Stal said.
"People usually associate bacteria with diseases and don't realise that we are actually healthy because of them."
Bacteria process the waste in humans, purify water and keep soil productive. Some bacteria are used in making fermented food, therapeutic drugs like insulin, and even washing powder.
And scientists believe microbes could also be used one day to develop new medicines or fuel sources.
The initial phase of the microbes project aims to create a network of marine microbiologists by the end of 2006, develop research priorities and decide how to organise databases.
In addition to cataloguing existing micro-organisms and discovering new ones, scientists also want to understand the evolutionary and ecological processes by which marine microbes diversity has been created and is maintained.
The project's leaders, however, have no illusions about the huge task they have undertaken and the many obstacles facing them, such as the inability to grow microbes in laboratories.
"At the end of the day the efforts will be constrained by financial resources," Sogin said.
Stal said they hoped to secure a long-term commitment from governments and other organisations to raise the billions of dollars needed for the task.
The project, due to run until 2010, has so far received a $900,000 grant from the New York-based Sloan Foundation.
"We need an amount of money comparable to money committed to space research," Stal said.
"Most of the research on biodiversity and extinction of organisms is all on elephants and zebra and antelopes and lions. I understand that - you can see them in zoos, they may become extinct and our grandchildren may not be able to see them.
"But they are not critical in terms of functioning of the Earth's eco-systems."