Phytoplankton, with the ability to remain dormant for up to a century, may have helped revive photosynthesis in the oceans following a global catastrophe around 65 million years ago, reports an article in Nature Communications this week.

Global darkness followed an asteroid impact 65.5 million years ago, causing the collapse of photosynthesis and massive extinction. However, coastal phytoplankton species appeared more resilient and many species survived.

Sofia Ribeiro and colleagues collected resting cysts of marine phytoplankton known as dinoflagellates from a fjord in Sweden. These phytoplankton were shown to grow after almost a century since they were buried in the marine sediment.

This work may provide a clue as to how the coastal species were able to recover more rapidly from the asteroid impact and in turn help restart photosynthesis in the oceans once conditions for life improved.