Phys.org // With a global reach of over 10 million monthly readers and featuring dedicated websites for science

 

Could lumpy metallic rocks in the deepest, darkest reaches of the ocean be making oxygen in the absence of sunlight?

'Dark oxygen': a deep-sea discovery that has split scientists

Polymetallic nodules and an abyssal urchin.

Some scientists think so, but others have challenged the claim that so-called "dark oxygen" is being produced in the lightless abyss of the seabed.

1. The discovery—detailed last July in the journal Nature Geoscience—called into question long-held assumptions about the origins of life on Earth, and sparked intense scientific debate.
2. The findings were also consequential for mining companies eager to extract the precious metals contained within these polymetallic nodules.
3. Researchers said that potato-sized nodules could be producing enough electrical current to split seawater into hydrogen and oxygen, a process known as electrolysis.

This cast doubt on the long-established view that life was made possible when organisms started producing oxygen via photosynthesis, which requires sunlight, about 2.7 billion years ago.

"Deep-sea discovery calls into question the origins of life," the Scottish Association for Marine Science said in a press release to accompany the publication of the research.

Delicate ecosystem

Environmentalists said the presence of dark oxygen showed just how little is known about life at these extreme depths, and supported their case that deep-sea mining posed unacceptable ecological risks.

Infographic showing the three different types of seabed zones being explored for potential mining.

"Greenpeace has long campaigned to stop deep sea mining from beginning in the Pacific due to the damage it could do to delicate, deep sea ecosystems," the environmental organization said.

"This incredible discovery underlines the urgency of that call".

The discovery was made in the Clarion-Clipperton Zone, a vast underwater region of the Pacific Ocean between Mexico and Hawaii of growing interest to mining companies.

• Scattered on the seafloor four kilometers (2.5 miles) beneath the surface, polymetallic nodules contain manganese, nickel and cobalt, metals used in electric car batteries and other low-carbon technologies.
• The research that gave rise to the dark oxygen discovery was partly funded by a Canadian deep-sea mining business, The Metals Company, that wanted to assess the ecological impact of such exploration.

It has sharply criticized the study by marine ecologist Andrew Sweetman and his team as plagued by "methodological flaws".

Michael Clarke, environmental manager at The Metals Company, told AFP that the findings "are more logically attributable to poor scientific technique and shoddy science than a never before observed phenomenon."

Scientific doubts

Sweetman's findings proved explosive, with many in the scientific community expressing reservations or rejecting the conclusions.

Exploration areas licensed by the International Seabed Authority, including to The Metals Company, a Canadian company.

Since July, five academic research papers refuting Sweetman's findings have been submitted for review and publication.

1. "He did not present clear proof for his observations and hypothesis," said Matthias Haeckel, a biogeochemist at the GEOMAR Helmholtz Center for Ocean Research in Kiel, Germany.
2. "Many questions remain after the publication. So, now the scientific community needs to conduct similar experiments etc, and either prove or disprove it."

Olivier Rouxel, a geochemistry researcher at Ifremer, the French national institute for ocean science and technology, told AFP there was "absolutely no consensus on these results".

1. "Deep-sea sampling is always a challenge," he said, adding it was possible that the oxygen detected was "trapped air bubbles" in the measuring instruments.
2. He was also skeptical about deep-sea nodules, some tens of millions of years old, still producing enough electrical current when "batteries run out quickly".
3. "How is it possible to maintain the capacity to generate electrical current in a nodule that is itself extremely slow to form?" he asked.
4. When contacted by AFP, Sweetman indicated that he was preparing a formal response.

"These types of back and forth are very common with scientific articles and it moves the subject matter forward," he said.

Journal information: Nature Geoscience

 

 

Our ability to cooperate with others may be influenced by how our attention is captured and directed, as much as by how altruistic we are feeling.

How information is presented can drive cooperative decision-making

by University of Birmingham  

Credit: Pixabay/CC0 Public Domain

According to a new study by researchers at the University of Birmingham jointly with the University of Zurich, choices made for individual reward or cooperatively for a joint reward can be influenced by presenting information to participants in configurations that naturally draw their attention. 

• The results are published in Communications Psychology.

Cooperation—defined as the ability of individuals to incur a personal cost for the benefit of a group—is a fundamental aspect of human behavior. Understanding how we can foster cooperation is essential for tackling many global challenges, from climate change to the spread of infectious diseases—and understanding what motivates people to cooperate is key to this process.

• Dr. Arkady Konovalov from the University of Birmingham and lead researcher said, "We found we were able to drive people to be a bit more cooperative simply through presenting particular information in areas of the screen where we knew they were directing their attention.

"While this was purely a laboratory-based experiment, it gives us some valuable insights into how we can better understand, predict and perhaps manipulate people's behavior to improve cooperation between individuals and groups."

In their experiment, the researchers used a well-established interactive experiment based on game theory, called the Prisoner's Dilemma. They invited 88 participants, a mixture of men and women aged between 18 and 35 years old.

The participants took part in a series of laboratory games in which they were invited to make decisions about cooperating for mutual benefit for them and a partner or acting alone for individual benefit. Different levels of reward were given for different decisions made.

• While the individual benefit might appear to be higher than the cooperation benefit, if both sides cooperate, the reward is higher still.

The choices available in each round of the game along with the rewards were visible to participants on a computer display. The researchers used eye-tracking technology to understand how people were reading and processing this information in each round of the experiment. 

• By manipulating where on the screen the choices were presented, the researchers found it was possible to influence the choices that people made.

• The team showed that when participants paid attention to the payoffs of others in the experiment, there was an increased likelihood that they would make cooperative choices. 
• When they paid more attention to their own reward, they were more likely to make a selfish choice.

By placing information about the payoffs of other participants in areas of the screen where they were likely to be given most attention, the researchers found they were able to influence cooperation rates among participants.

Surprisingly, although participants followed a natural screen-reading pattern of looking at the top left of the screen first, before reading information lower down, the researchers found that cooperation was higher when the 'cooperation information' was placed at the bottom of the screen.

More information: Manipulating Attention Facilitates Cooperation, Communications Psychology (2025). DOI: 10.1038/s44271-025-00206-9

Journal information: Communications Psycholog

 

Scientists study fish behavior during dyeing of the Chicago River for St. Patrick's Day

Every year as part of the city's St. Patrick's Day celebrations, thousands of onlookers clad in green cheer on a boat crew sprinkling orange powder into the Chicago River to turn it a festive shade.

Understanding your dog's body language: A guide to canine communication

Without the gift of gab, dogs are left to rely on a bark, a tail wag, or, sometimes, even a snarl to communicate with their two-legged companions. However, as we attempt to connect with our canine friends, understanding the ...

House cats infected with bird flu in New York City, health officials say

Two cats in different households in New York City were infected with bird flu, the city's health department announced.

Dismay for Big Bear bald eagle family as eaglet dies in winter storm

Concern turned to grief this weekend as fans of Big Bear's beloved bald eagle couple Shadow and Jackie learned one of the three eaglets that hatched in the pair's nest this month did not survive a winter storm.

How the EPA's environmental about-face could upend California's climate efforts

The Environmental Protection Agency's plan to repeal or weaken more than two dozen regulations could deliver a direct blow to California policies on air and water quality standards, electric vehicle initiatives and efforts ...

Camera trap images from URI's North Woods survey contribute to nationwide research project

Adjacent to the University of Rhode Island's main campus, North Woods encompasses 225 acres of forest, wetlands, and headwater streams. Thanks to camera trapping efforts from the Department of Natural Resources Science, images ...

AI image recognition detects bubble-like structures in the universe

To learn more about the deepest reaches of our own galaxy and the mysteries of star formation, Japanese researchers have created a deep learning model. The Osaka Metropolitan University-led team used artificial intelligence ...

Researchers push for ISL as official language to aid deaf education in India

Around one in five (over 19%) of India's deaf and hard-of-hearing children were out-of-school in 2014, according to a survey conducted for the Indian Government. A new study calls on the government to address this ongoing ...

Why are proposed deep-sea mining rules so contentious?

After more than a decade of negotiations, a new round of talks to finalize a code to regulate deep-sea mining in international waters begins Monday in Jamaica, with hopes high for adoption this year.

Race to name creatures of the deep as mining interest grows

In the cold, lightless Pacific Ocean deep, the seabed is scattered with metal-rich rocks coveted by miners—and huge numbers of strange and rare animals almost entirely unknown to science.

Stranded US astronauts to return to Earth on Tuesday: NASA

A pair of US astronauts stuck for more than nine months on the International Space Station will be returned to Earth on Tuesday evening, NASA said.

Resilience doesn't always mean persevering—it can be found in inaction and silence, too

Young people today face increasing levels of uncertainty. They're navigating volatile job and housing markets and contending with a future that's likely to be significantly marked by the climate crisis. Evidence also indicates ...

Western Europe's oldest human face discovered in Spain

The research team at the Atapuerca archaeological sites in Burgos, Spain, has just broken its own record by discovering, for the third time, the oldest human in Western Europe.

Oil spill in Ecuador river brings emergency declaration

An oil spill in northwestern Ecuador has turned a river black, prompting authorities to declare an environmental emergency and order residents to ration drinking water.