Like something direct out of scientific discipline fiction , a platyhelminth burrows into a fish and makes its way into the heart of the dupe , where it then takes control of the unfortunate horde . But depending on the years of the parasite , it makes the fishbehave in different way .
When the eye good luck ( Diplostomum pseudospathaceum)is untested , it forces the septic fish to act in a direction that lessens the chance it will be eaten , making it quell near the bottom of the H2O and move less . As shortly as the parasite has matured and is ready to move on to its next host , it reverses these behaviors , making the fish swim near the surface and move around more . This increase the chance the fishy host will be eat on by a passing fowl .
But the parasite is not finished there . When it is take in by the wench , matured flukes mate in the avian stomach and their subsequent bollock are then pooped out into the water . When these hachure , the larvae go in search of a snail to enter , where they grow and multiply . Finally , they will their mollusc host to fill out the cycle , infecting a fish and migrate to the lens in the middle to begin their controller .
While the sponge is nothing unexampled , and previous inquiry conduct by the same group has already investigate how the sponge makes young fish comport in a way that minimizes the chance they will be eaten , this latest work has focused on the 2d phase of ascendance . write inBehavioral Ecology and Sociobiology , the researchers have picture how the mature parasites in the fish seek to increase the chance their legion will be consumed by bird .
They comport experiments in which they tested how both infected and uninfected fish comport in tanks , and how they then responded to dame attacks , which were simulated by passing a bird - form shadow over the marine museum . When the bird apparition passed over , both infected and uninfected fish froze , but the infected fish set about moving again much more rapidly .
Many parasites are known to take over their host and control them . There arethousands of speciesof cordyceps that infect louse and alter their behavior , and the parasiteToxoplasma gondiiis even thoughtto make mice more probable to get chomped on by cats . But this parasite is unearthly in that at unlike leg , it makes the fish bear in different way .
The results of this modish field reveal that the behavioral changes cause by the leech play a vital part in freshwater food webs .
[ H / T : New Scientist ]
