In a May 2013 paper, researchers at the University of Manchester revealed stunning 3D images of the metamorphosis of the painted lady butterfly, Vanessa cardui.
The team used CT scanning to capture the tiny anatomy of the pupa on its first day.
After a caterpillar transforms into a pupa, it begins another change inside the chrysalis, a hard outer shell. The CT scanning revealed that even at this early stage of metamorphosis, many respiratory airways (in blue) are well-developed.
In the past, researchers wanting to study insect development would typically dissect a new insect at each stage of development, a timely and laborious process.
By day 13, many of the internal structures present in the butterfly are already in place. Here, tracheal system (blue), midgut (red), and waste tubules (orange) are clearly visible.
The new method can track the development of a single living organism throughout development. Over the course of two weeks, the team revealed the hidden changes occurring inside the chrysalisl.
Adult takes wing
By the time the butterfly nears completion of metamorphosis, the eyes, gut structure and antennae are clearly visible in the scans.
Radiographs of the chrysalis reveal a nearly-complete transition. The new technique could be used on other animals, such as bees and maggots, to study their development, the researchers say.