The BBC has an interesting article on whether jellyfish help to stir up the oceans, helping to distribute heat, nutrients and chemicals. They draw their material from a recent article in Nature where researchers used a green dye to see the effects caused by swimming jellyfish.
Over 50 years ago Charles Darwin (no, not that one – his grandson) identified that animals contribute to marine turbulence and the influence of this “biogenic” mixing in comparison to wind and tides has been debated ever since. This recent research has shown that small creatures as well as very large ones contribute. The researchers studied jellyfish because they were relatively easy to study, but they feel that crusteceans like krill are more likely to be more significant since there are so many of them.
The principle is to do with aerodynamics. That a creature at depth will carry colder, deeper water up with it as it migrates upwards. The effect is likely to be largest in specific areas where there is a high concentration of life.
For more information, go to the BBC’s website.
