Ocean life:Even in the deep dark ocean where sunlight never reaches, life cycles are still governed by the seasons. And despite being remote from human activity, species living on the ocean floor may not be as safe as we think.
Researchers have made surprising findings about the "islands" of exotic deep sea life thriving around volcanic vents and other sea bed features that were undiscovered until 30 years ago. Their lives follow seasonal cycles of the sunlit world above, which may mean that they are at risk from climate change.
At the press launch of the BA Festival of Science, Dr Jon Copley, a marine biologist at the School of Ocean & Earth Science, said: "I used to think these deep sea communities would be safe from whatever havoc happens up here. But finding seasonality down there shows that life beneath the waves is far more connected than we realised."
"There may be nowhere for life to hide from the effects of climate change or asteroids hitting the Earth," said Dr Copley, who is a marine biologist at the School of Ocean & Earth Science, University of Southampton.
"We are enjoying a golden age of discovery as we visit these previously-unexplored "islands" in the abyss and we are gaining new insights into the patterns of life throughout the oceans as we do so," he said.
He explained that scientists used to think these islands on the ocean floor acted as "air-raid shelters" for some species during global catastrophes.
"Carpets of mussels and swarms of shrimp thrive in these seemingly hostile environments, nourished by minerals seeping from the Earth's crust, a source independent of the world above," said Dr Copley.
Now, he and his colleagues have found a direct link to the world above. They have identified seasons in the sex life of these creatures in the deep seas, as they breed in late autumn and hatch their offspring in early spring.
"They have plenty of food all year round as adults, thanks to life-sustaining minerals seeping from the Earth's crust.
"But their offspring grow up away from these havens, feeding on whatever sinks from sunlit surface waters. So the animals time the release of their offspring to coincide with a spring bloom in microscopic plant life growing at the surface."
This link has been overlooked, according to Dr Copley.
Although there is no evidence yet, Dr Copley warns: "As climate change alters the pattern of life in surface waters, these newly-discovered connections could carry its effects to the remote corners of the ocean depths."
Dr Copley is presenting the Charles Lyell Award Lecture "Seasons where the sun don't shine: chasing island hopping shrimps in the abyss" today at the festival in York.