With their bright orange wings and spectacular migration, monarch butterflies (Danaus plexippus) are one of the most popular insects in the world. However, their population has declined in recent decades as they have faced habitat loss and other threats.
Monarch butterfly life cycle
Monarch butterflies go through four life stages: egg, larva, pupa, and adult.
They can mate multiple times, sometimes for 16 hours at a time. Afterward, the female begins to lay eggs on the milkweed plants. Monarch butterfly eggs are the size of the head of a pin and feature vertical ridges.
Female monarch butterflies typically lay 300 to 500 eggs on different species of milkweed plants (Asclepias), but they are known to lay more than 1,100 eggs in captivity.
However, only about 10% of those eggs survive to the larval stage due to heavy predation by spiders and bedbugs. The eggs take between three and five days to hatch.
Facts about its wings
Monarch butterflies have orange wings with a pattern of black veins. The females are of a darker hue and have thicker veins, while the males have two black spots in the veins of their hind wings.
The edge of the wings is black with white, brown and yellow spots on both males and females.
On the other hand, monarch butterflies usually measure between 7 and 10 centimeters, as the National Wildlife Federation maintains.
They’re poisonous?
Monarch butterflies are poisonous to most of their predators. This is because during the larval stage, they feed exclusively on milkweed sap, which contains toxins called cardenolides.
Thus, adult butterflies retain the toxins they ate as larvae, making them poisonous to predators such as birds, frogs and lizards, according to research published in the journal Current Biology.
In fact, the bright colors serve as a warning sign of its toxicity to other species. And while most birds learn to associate an insect’s bright colors with bitterness and vomiting, some birds, such as the black-headed thick-billed, have evolved to enjoy the taste of monarch butterflies.
