Toxic to aliens -- but key to health of planet

Jun 18, 2008

Scientists at the University of Leicester are using an ingredient found in common shampoos to investigate how the oxygen content of the oceans has changed over geologically recent time.

The same ingredient, which was also used to fight off alien invaders in the film "Evolution", is a widely available dietary supplement used by many people.

The ingredient, selenium, is an anti-oxidant and an essential trace nutrient in our diet. It belongs to a group of elements whose behaviour is controlled by the concentration of oxygen in the environment.

This study represents a first attempt by scientists to use selenium in this way and is part of research student, Andrew Shore's, PhD project. It involves measuring the isotopic ratios of selenium in sediments.

One possible outcome of the project is that the results could give scientists a global picture of the changing oxygen content of the oceans through time. Previous studies have tended to focus on local variations in ocean oxygen content.

The oxygen content of oceans can also be used as an indicator of the "overall health" of the oceans. The recent report from the Intergovernmental Panel on Climate Change (IPCC) states changes in fish populations are "associated with changes in oceanic oxygen levels." Therefore an understanding of oxygen in the oceans is not only important for the past but also for the future.

"We are using samples from an ocean basin off the Venezuelan coast which previous studies have shown to have changed its oxygen content over the last 500,000 years," explained Andrew.

Without oxygen living things suffocate. Six hundred million years ago, the only life that could survive was tiny single-celled organisms. Then suddenly 540 million years ago complex life began to thrive, possibly as the "miracle molecule", oxygen, became abundant on Earth.

Andrew added: "Our understanding of the changes in atmospheric oxygen is good, but our planet is 70% covered by oceans. Determining the oceanic oxygen content is very difficult - it is linked to the atmosphere, plankton growth, and ocean circulation patterns."

Source: University of Leicester

Explore further: 2014 Antarctic ozone hole holds steady

add to favorites email to friend print save as pdf

Related Stories

Migrating animals' pee affects ocean chemistry

Oct 09, 2014

The largest migration on the planet is the movement of small animals from the surface of the open ocean, where they feed on plants under cover of darkness, to the sunless depths where they hide from predators ...

A salty, martian meteorite offers clues to habitability

Aug 28, 2014

Life as we know it requires energy of some sort to survive and thrive. For plants, that source of energy is the Sun. But there are some microbes that can survive using energy from chemical reactions. Some ...

Recommended for you

2014 Antarctic ozone hole holds steady

7 hours ago

The Antarctic ozone hole reached its annual peak size on Sept. 11, according to scientists from NASA and the National Oceanic and Atmospheric Administration (NOAA). The size of this year's hole was 24.1 million ...

New study finds oceans arrived early to Earth

10 hours ago

Earth is known as the Blue Planet because of its oceans, which cover more than 70 percent of the planet's surface and are home to the world's greatest diversity of life. While water is essential for life ...

Magma pancakes beneath Lake Toba

10 hours ago

Where do the tremendous amounts of material that are ejected to from huge volcanic calderas during super-eruptions actually originate?

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.