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=The Plant that Pretends to be ill=

by Michelle Lee 9AR
We all know that kids pretend to be sick so that they won't have to go to school. But a plant pretending to be sick? Yes, a plant. And no, plants don't go to school. This plant, found in the rainforests of Ecuador, pretends to be sick so that pests like the mining moths won't eat it's healthy, green, leaves. It is the first plant found to be able to do this.

Experts think that the not-sick plant might be able to explain a common pattern on the leaves of a variegated plant. Variegated plants are plants in which the cells in their leaves lose chlorophyll and their ability to photosynthesize, causing their leaves to grow white. It has been long thought that Variegated plants would be in a disadvantage with other plants, because of their disabitlity to photosynthesize. However, with the discovery that plants can mimic illness, it seems that some variegated plants might just be pretending to be ill so as not to be eaten. Variegated patterns on leaves are usually white marks and swirls. Mining Moths lay their eggs, which soon hatch into caterpillars, who them munch through the leaves. A white trail of damage is left. It was the realization of the similarity between the two patterns that led to the theory.  Left: A leaf damaged by the Mining Moths. Right: A plant faking illness.

To test the theory, the experts tried an experiment. Using white correction fluid, they mimicked the appearance of variegation on numbers of healthy leaves. After leaving them for three months, they counted the number of green, healthy leaves damaged by the mining moths, the number of variegated leaves damaged, and the numbers of those painted with the correction fluid. The results were what they had expected. "Visibly variegated leaves were significantly less frequently damaged by mining moth larvae then plain green ones." says Lied- Schumann, an expert botanist. While 8% of green, healthy leaves were infested, only 1.6% of variegated leaves were infested. The percentage of the ones painted to look as though they were variegated were only 0.4%. Researchers now believe that the plant fakes being ill so that the mining moths wouldn't lay any further larvae on the leaves, as they assume that all nutrition has gone from the leaves. Though it was believed that the variegated leaf's disability to photosynthesize put it in a disadvantage, it is now thought that the fact that it won't be eaten puts it in more of an advantage then other healthy leaves. This suggests that variegated leaves can survive better in the wild, proving it important in the long-term success of it's species.

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