Yale astronomer Pieter van Dokkum has a passion for insects—especially dragonflies, which he photographs in exquisite detail near his home in Connecticut. He captured this time-lapse video, below, of the metamorphosis of a common green darner dragonfly from a larval nymph.
More of his photos can be found in the new large-format book Dragonflies: Magnificent Creatures of Water, Air and Land (Yale University Press, 2015), which we profile in Scientific American’s April issue. Here, in van Dokkum’s words, is the story behind the video:
“In the early evening the dragonfly nymph climbs to the top of a reed. She then bends her abdomen while breathing in air, cracking open her skin right below the head. The dragonfly emerges headfirst and upside down. Hanging from the nymph shell, she has to wait until her legs harden before she is able to crawl out and turn around. In the space of about 15 minutes she extends her wings by pumping air into them. Over the next three to four hours her abdomen slowly extends and hardens. Shortly before dawn she spreads her wings. With the first light of the sun the newly emerged dragonfly takes off on her maiden voyage, leaving her old life (and skin) behind.
The sequence of photographs was taken over the course of a single night, starting around 10 P.M. and ending around 8 A.M. I took these shots manually, with a camera on a tripod: as described above, some phases happen quite quickly, requiring a shutter press every second or so, and others take several hours.
I had visited a pond near my home for several nights in search of a nymph that was about to undergo metamorphosis. This involved wading in the pond at night and inspecting the vegetation to see if there was a nymph on its way to the top. I finally found one and set up my camera, a comfortable chair and a book, plus reading light: I was expecting to spend the entire night there. The moment everything was in place lightning filled the sky and it became clear that a big thunderstorm was about to begin. As there was no possibility of safely photographing the nymph where we were, I decided the both of us should leave. I cut off the reed, with the nymph halfway to the top, and gently placed it on the passenger seat of my car. I drove home, secured the reed in a small tripod just outside the garage and set up my camera in the garage looking out. The nymph continued its upward journey as if nothing had happened and began the metamorphosis after it reached the top.”