Think you’re a survivor? You’ve got nothing on the cane toad, former native of Central and South America, now scourge of Australia. To snuff out their competition for resources, cane toad tadpoles will actually cannibalize nearby cane toad eggs. And all those eggs the tadpoles are too full to gobble up? Well, researchers recently learned that the hardy amphibians have that covered, too: cane toad tadpoles release chemicals into the water that stunt the growth of developing embryos.

Scientists already knew that cane toads communicate with pheromones and use these chemical signals to locate tasty eggs. They also wondered if the pheromones have another, more insidious, purpose. Biologists at the University of Sydney set up a simple experiment to find out. They placed cane toad eggs in 20 containers filled partially with water; in 10 of those containers, they added tadpoles and separated them from the eggs with mesh screens.

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We knew parasitic wasps were menacing; DISCOVER covered some of them in our gallery of zombie animals controlled by parasites, including a caterpillar that becomes the bodyguard of wasp larvae after they take over its mind. But we didn’t know just how many kinds of these treacherous insects exist.

Now, after completing a decades-long study with other researchers, James Whitfield of the University of Illinois says that there are almost twice as many species of these wasps as researchers had previously believed.

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Some plants simply can’t handle their climate changing, and an increased temperature kills them off. Others, as DISCOVER recently covered, manage to migrate to a cooler climate when nature turns up the heat. But a grass found on a rocky hillside in Northern England has chosen a third option: Stay and tough it out.

Researchers from Syracuse and Sheffield universities had been toying with this particular ecosystem for 13 years. Herbs and shrubs abound in the rocky region; more than 50 species of plants per square meter can be found, and researchers decided to put them all to the test. They divided the area into smaller plots, and varied the climate of those plots wildly. One section was given 20 percent more water than its average yearly amount; another area had shelter built over it to simulate drought. The scientists even planted heating cables underneath one plot to simulate a warmer-than-average winter.

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