#ecology

#ecology

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

The Amazing Ecological Transformation of Ascension IslandAscension Island in the south Atlantic was an unremarkable volcanic island formed around a million years ago. It had some grass and a freshwater spring, and sea turtles and birds made it their home. In 1815, a British garrison planted a vegetable garden and brought in livestock, but there were no trees at all on the island. When Charles Darwin's famous Beagle expedition stopped there in 1836, he pondered the island's possibilities.Seven years later, British botanist and explorer Joseph Hooker visited the island. Edged on by Darwin, Hooker advised the British Navy that vegetating the island would help capture rain and improve the soil. Trees would capture moisture and reduce evaporation, while their roots will break down the lava rocks and create thicker and loamy soils.Beginning in 1850 and continuing for a decade, the Royal Navy imported thousands of saplings encompassing more than 330 different species from botanical gardens in Europe, South Africa and Argentina. The plants were specifically chosen to withstand the harsh conditions of life on this volcanic desert. In twenty years, more than five thousand trees had begun to take root. They covered the crown of Green Mountain, the highest point of the island, in a lush halo of bamboo, while tall Norfolk pines flanked the slopes. These trees were planted to be used as replacement masts for sailing ships.