One of the most intriguing occurrences in nature is when a caterpillar transforms into a butterfly. This phenomenon known as metamorphosis separates youth from adulthood, two entirely separate worlds.
We already have an idea of what happens inside the pupa as the larva breaks down its own tissues by releasing enzymes. Some organs remain intact as muscles break down into protein cells to be reused later. Science textbooks usually explain this as a "soup", a mixture of structures used to create the adult body parts including the antennae, eyes, legs and wings.
To study the stages of the caterpillar, scientists would have to destroy the insect by dissecting it for observation. Scientists would have cut open many pupae at different stages of development to get a clear understanding of the transformation process.
Using a new technique called a micro-CT, two teams of scientists began capturing a series of images that show caterpillars undergoing metamorphosis. X-rays capture cross sections of the caterpillars inside of their pupae, to be combined into a virtual 3-D model.
"We use this 3D imaging technology in archaeology to analyze the internal structure of objects such as bones and pottery, but it works just as well for small bodies with complex internal anatomy like a chrysalis," archaeologist Professor Kate Robson Brown, from the University of Bristol, said.
Thanks to modern technology, researchers were able to see the structures of each organ inside the pupa. The researchers were also able to watch how each organ changes over a period of time by scanning the same chrysalis over the course of many days. With the use of this technique, the caterpillars remain unharmed, as insects are capable of tolerating large amounts of exposure to radiation.
As reported by the BBC, one of the teams of scientists analyzed the stunning blue morphos right before the butterfly emerged. The footage is featured in the BBC Four documentary called Metamorphosis: The Science of Change. Check out the 3D scans in the video below: