Zooplankton incidences

2001/07/05 Roa Zubia, Guillermo - Elhuyar Zientzia

• Zoologia
• Ozeanografia

When the sun rises, the zooplankton slowly sinks and in the afternoon, when the light weakens, it returns to the top. Until now, to explain this type of migration, it was recognized that zooplankton had to flee from the predators who hunt with vision. However, this migration has also been observed in areas without fish (predators), so there must be another reason.

In Germany, researchers at the University of Munich have dared to give a new explanation. The researchers have not ruled out the explanation of the escape, but with the zooplankton of the genus Daphnia they have carried out numerous studies in the laboratory and have concluded that the ultraviolet rays of the Sun influence migration a lot.

In the zooplankton studied, the more pigments they contain to protect against ultraviolet rays, the more they are submerged. According to the zoologists, this means that the light of the Sun incites to submerge the zooplankton. In this immersion, these species also benefit from other benefits, such as those related to predators.