A new Israeli study reveals that the presence of parasites can surprisingly have a positive effect on the structure of an ecosystem and play a key role in the design of the habitat and in sustaining its biological diversity, Tel Aviv University (TAU) revealed on Sunday.
The research was conducted by researchers on tiny daphnia water fleas, which can be found mainly in winter ponds in Israel.
Since winter pools are closed habitats, the competition between different species has particularly significant effect on the biological diversity in the pool, TAU said in a statement.
"In the population of water fleas in Israel, we found one species called Daphnia similis, whose nickname in the laboratory is 'Super Daphnia' due to its almost complete resistance to parasites. Nevertheless, this 'Super Daphnia' does not become the dominant Daphnia species in ponds. The most common species is actually Daphnia magna, which is highly vulnerable to a wide variety of parasites," the statement quoted Frida Ben-Ami, professor of TAU and a leading researcher, as saying.
Results of the study showed that in a parasite-free habitat, the parasite-sensitive species, which is the most common Daphnia species in the wild, is the one that won the competition, even forcing the disappearance of the parasite-resistant "Super Daphnia."
However, in habitats with parasites, the survival of the parasite-sensitive Daphnia decreased dramatically and the "Super Daphnia" population became established, demonstrating an environment where coexistence between the two species is possible via the mediation of parasites.
According to the statement, researchers believe the results emphasize the important role of parasites in shaping biodiversity, as parasites can mediate competition between Daphnia species.
The study has significant implications for obtaining a better understanding of systems in which both sensitive species to parasites and less sensitive species to parasites co-exist, and thus may help guide efforts in dealing with biological invasions and even help reduce the threats to endangered species.