#entomology

#entomology

Male Milkweed Butterflies Feed On Live Caterpillars To Steal Chemicals Which Function As “Wedding Gifts” To Their MatesButterflies are generally peaceful creatures. But not all of them. There are butterflies who are brutal, specifically male milkweed butterflies. These butterflies will do anything to please their mates, including feeding on young caterpillars — their family’s young. Yup. That’s how brutal some butterflies can be. But what reason would they have to target young caterpillars? The answer is, these caterpillars are a great source of chemicals, which the adult males use to produce mating pheromones. These pheromones serve as gifts to the females during courtship.Milkweed butterflies have been previously reported to feed on dead chemical-containing insects, but these butterflies doing the same thing on living insects is a first. PhD candidate Yi-Kai Tea, the lead author of the study, says that this is the first time such behavior was documented.“The behaviour does not fit neatly in the traditional modes of predation, parasitism, or mutualism, and so presents a new challenge to evolutionary theory. We have coined it ‘kleptopharmacophagy’ – chemical theft for consumption.”To supplement the chemical supplies they obtain as caterpillar juveniles, the butterflies engage in a behaviour known as “leaf-scratching”. “They damage [chemical containing] plants with their sharp tarsal claws, liberate plant juices and imbibe them using their long, curly tongues,” said Mr Tea.Scratching at live caterpillars, however, had never previously been reported. “Caterpillars are essentially bags of macerated leaves; the same leaves that contain these potent chemicals the milkweed butterflies seek out. To adult butterflies, they may simply be an alternative source of chemicals on which to feed,” said Mr Tea.The study has been published over at Ecology’s The Scientific Naturalist.Nature sure is weird, and could sometimes be horrible.(Image Credit: Yannkemper/ Wikimedia Commons)#Butterflies #MilkweedButterflies #Kleptopharmacophagy #Mating #Ecology #Entomology #Pheromones #Caterpillars

This Self-Righting Drone Uses Ladybug Inspired Wings to Get Back Up“When life knocks you down, you’ve got to get back up.”Ladybugs stand by this quote, and quite literally. When knocked down and stuck on their backs, ladybugs are capable of self-righting themselves by utilizing their strong outer wings, known as elytra, and by thrusting their legs or hind wings in order to reorient themselves.These little creatures have existed for a very long time and Charalampos Vourtsis—a doctoral assistant at the Laboratory of Intelligent Systems, Ecole Polytechnique Federale de Lausanne in Switzerland—notes that “Over that time, they have developed several survival mechanisms that we found to be a source of inspiration for applications in modern robotics.” Inspired by this, researchers have developed self-righting drones, equipped with artificial elytra for the same purpose. This allows the drones to stabilize and reorient themselves when caught in awkward positions and even improves their aerodynamic capabilities during flight, as tests and experiments by researchers have shown. For example, long elytra, which they found were the most effective, were tested by the team on different inclines of 10°, 20°, and 30°. The drones were successful in self-righting themselves in all scenarios except for the steepest incline. The drones were also able to reorient themselves on several different terrains, namely: pavement, coarse sand, rocks, shells, and wood chips. While the drones were unable to do so in fine sand and grass, the researchers believe that further optimization may help the drones to accomplish this. A non-negligible lift offsetting the weight of the drone was also noted by the team, regarding it as a bonus.Image: EPFL-LIS#drones #ladybug #elytra #aerodynamics #insects #science #engineering #entomology #stabilization