Life in the Deep Sea is Mostly Mysterious

The deep sea covers around 65% of the planet’s surface, making it the largest habitat on Earth. Yet, this vast area remains largely unknown. The remoteness of the deep sea, which lies below 200 m, makes traditional ecological data collection methods extremely difficult. As a result, very little is known about the lives of deep sea creatures.

“This is the largest habitat on the planet, but we know very little about how it functions and how it may react to future changes,” says Michelle Taylor of Oxford University. “Humans are continuing to encroach on this habitat and that’s not going to change. We have to start thinking about how we’re going to manage this environment responsibly.”

A first step is focusing on population genetics – the comparison of genetic diversity within and between populations of individuals. This approach can help scientists gather basic ecological information on deep sea animals and model patterns of connectivity and genetic diversity.

With fellow Oxford University scientist Christopher Roterman, Taylor recently reviewed all the population genetics studies of deep sea invertebrates published to date. Their results highlight the disparity between our limited knowledge of deep sea ecology and the growing impact of humans on this habitat.

Preserving the Deep Sea

Despite its remoteness, human activities are encroaching on the deep sea. Pollution, fishing, climate change, and mining are all intensifying and affecting populations of deep sea creatures. There is growing awareness that the habitats and resources in the deep sea need to be sustainably managed, but more data is required to guide these actions.

“We are trying to understand how resilient deep sea populations are and how resilient we anticipate they could be under the increasing threats of climate change and other human impacts,” says Roterman.

The biggest issue is collecting the knowledge that could be used to responsibly manage the deep sea before we damage it too much.

“The exploitation is outpacing the exploration,” says Taylor. “And that’s worrying.”