The scent that guides sea birds towards their prey could also be helping to cool our climate.
Researchers have found that seabirds are attracted to a scent called DMS (dimethyl sulphide), which is emitted by phytoplankton when it is being eaten by krill.
That signal, used by phytoplankton to draw seabirds which eat krill, forms sulphur compounds in the atmosphere that promote cloud formation and help cool the planet.
Seabirds consume the krill, and fertilise the phytoplankton with iron from their droppings, further encouraging growth.
But the number of seabirds is in sharp decline, which could lead to a disruption of ocean ecosystems and a lower level of the DMS which is helping cool the planet.