β How does a caterpillar change into a butterflyβ?β
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These tiny eggs will develop not only the parts needed to be a caterpillar but also later a butterfly. They grow "imaginal discs," clusters of cells that later form adult body parts like wings, antennae, and legs. The journey to a butterfly starts at inception.
After hatching from its egg, the butterfly is in its larva, or caterpillar, stage. It now has one job and one job only: EAT.
For the next few weeks, the caterpillar devours leaves to fuel its rapid growth. As it grows plumper, it will molt (shed its skin) several times to transform into a larger version of itself. Some species of butterfly will end up being 100 times larger than when it started.
Eating can also be a defensive mechanism. Some caterpillars will intentionally eat plants that contain toxins, making them poisonous to other predators even after they've transformed into butterflies.
It's "The Final Molt-down" for the butterfly as it molts for the last time to form a shiny, hard chrysalis that protects against extreme temperatures, parasites, and moisture loss.
Now the fun part begins: How do you transform all those caterpillar parts into butterfly parts? You liquefy yourself, of course!
The caterpillar will digest itself, releasing enzymes that dissolve most of its tissues. It's often said that the chrysalis will contain a "soup" of caterpillar parts, but it's probably more accurate to call it a "stew" because not all of its body parts dissolve.
Crucially, the imaginal discs survive this digestion process and use this protein-rich broth to fuel the rapid growth of wings, antennae, legs, eyes, and other butterfly features.
β "Figure 1" by Royal Society is licensed under CC BY 3.0. |
As butterfly parts grow (like the wing vein structure, shown in blue above), some parts get smaller (like the digestive system, shown in red) since butterflies will change their eating habits from fibrous plants to simple nectar. This process of transforming from a caterpillar to a butterfly will take about 2-4 weeks to complete.
The adult butterfly will emerge from its chrysalis with the help of a hormone that provides the strength needed to bust out. It's a little less dramatic than how the Metapod evolves into a Butterfree in PokΓ©mon, but it's still an amazing process.
β Source: Be Smartβ |
And after being folded up for several weeks, the butterfly's wings need to stretch out. It pumps a blood-like substance called hemolymph into its wings so they can expand and harden for flight.
Now the adult butterfly has a new job: make more butterflies. A butterfly will court mates with scents and elaborate aerial dances. Some butterflies lay their eggs close to where they were born, but others, like the Monarch butterfly will embark on continent-spanning migrations to lay their eggs on the other side of the world. Then the cycle will begin again.
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βSources for this week's newsletterβ
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"Telling the bees is a Western European tradition in which bees are told of important events, including deaths, births, marriages and departures and returns in the keeper's household....After the death of Queen Elizabeth II in 2022, the Royal Beekeeper, John Chapple, informed the bees of Buckingham Palace and Clarence House of her passing and the accession of King Charles III."
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