Evolutionary biologists retrace the history of life in all its wondrous forms. Some search for the origin of our species, others for the origin of birds. Now researchers reported insight into the origin of zombies — in this case, ants zombified by a fungus. Sometimes an ant will step on a fungal spore, which then multiplies into new cells. The ant goes on with its life — and the fungus — Ophiocordyceps — keeps growing until it makes up nearly half of the ant's body mass. When the fungus finishes feeding, it sends signals to the ant's brain, causing it to leave the nest and climb a plant. The fungus glues the corpse to the leaf. Finally, the ant's head bursts a giant stalk, showering spores onto the ant trails below.

Parrots around world waste a lot of food

Polly wants a cracker. Polly eats one bite and flings the rest to the floor. A study in Scientific Reports said wild parrots also waste food, an unusual habit in the animal kingdom. Ornithologists tracked this behavior in 103 species in 17 countries. The data showed parrots are more likely to drop unripe fruits than ripe ones, and they're more careful during breeding season. "For human production, you cut fruits to make the crop better," researcher Esther Sebastián-González said. "So maybe the birds are doing something like that."

Scientists engineer blight resistant tree

In a feat of genetic engineering, about half the chestnuts collected at this station at New York state's College of Environmental Science and Forestry feature a gene that provides resistance to blight that virtually wiped out the American chestnut tree generations ago. Researchers will soon seek federal clearance to distribute the modified trees as part of a restoration effort. Opponents warn of starting an "irreversible experiment" in a highly complex ecosystem. But proponents like Professor William Powell, a molecular plant biologist, said, "We have this technology, it's a very powerful technology, and we can use that now to save a species."

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