Natures wonders: water flies adapt to avoid capture (Introduction)

by David Turell , Wednesday, July 13, 2022, 22:36 (652 days ago) @ David Turell

They have become too big for capture:

https://www.sciencedaily.com/releases/2022/07/220713114649.htm

"Water fleas are masters of adaptation. Researchers from Ruhr-Universität Bochum (RUB), the Albert-Ludwigs-Universität Freiburg and the Technical University of Darmstadt have discovered that they can defend themselves not only against animals but also against carnivorous plants. They showed that water fleas swim more slowly and develop lateral spines in the presence of the aquatic plant Utricularia (bladderworts). It seems that both mechanisms make it more difficult for the carnivorous plant to suck them into its trap.

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"This change in behaviour and the adaptations in body structure proved effective. The team compared how often animals that had grown up without the plant were eaten compared to animals that had been exposed to the plant. In fact, the latter were eaten less frequently. "This indicates that the activatable adaptations are actually defences against the plant," concludes Sebastian Kruppert.

"'We assume that the appendages let the water fleas grow wider than the diameter of the suction trap entrances," as Martin Horstmann describes the process. "The traps are different sizes, but the smaller traps at least can no longer ingest the animals." Since the water fleas with defences are also slimmer, the water current can probably flow past them more easily. Moreover, the slower swimming movements probably trigger the traps less often.

"'We hadn't been aware of any other case where animals can defend themselves against attacks from plants," as Ralph Tollrian outlines the special nature of the discovery. "The fact that various defences such as behavioural adaptations and changes in body structure can simultaneously be observed shows how adaptable and fascinating these tiny animals are.'"

Comment: back to the same issue: species adaptation or help from God.