Monday 2 July 2018

What are dragonflies for?




A young lady had just seen an emperor dragonfly.  While impressed with its size she wasn't really sure how to react. "What are they for?" she asked.

That is a huge question for me to answer.  I'm used to people asking the same question about wasps, ants and mosquitos that people regard as pests.  "Why do we have to put up with them? They are useless!" That makes sense. To most of us, they are just a nuisance.

A creationist might argue that these creatures were created from the mind of God for some particular purpose. Perhaps all of creation, including humans, was put on earth as part of some great purpose that we can't comprehend? I don't think so.

A Darwinist would tell you that life evolves due to natural selection, so that all of the vacant niches in an ecosystem are filled by a diversity of animals and plants. And we are just one of those animals! What is our niche then? Certainly a very complex one and a dominant one, but that may not last for long. In fact, it hasn't lasted long.

Dragonflies have been here for 300 million years while we have only just arrived. So a dragonfly might well ask, "Humans? What are they for?"

On another level, I could paraphrase the question in other ways. "What do dragonflies do? How do they contribute? Why should I care?"

My first reaction is that dragonflies are stunningly beautiful. The intricacy of their biology and the amazing colours and patterns that they have are justification enough for caring about their conservation. You won't find anything that beautiful in Top Shop or Jack Wills and you don't have to pay a licence fee to enjoy them in a visual sense.

I was only a little surprised to find that this young lady had no idea about the life cycle of a dragonfly.  Like the earliest naturalists such as Gilbert White, she found it amazing that they don't come from caterpillars. The adults lay their eggs in water where they live for several years as nymphs. That sounds rather poetic and sweet but those nymphs are major aquatic predators that eat anything from mosquito larvae to sticklebacks. Like the monsters in the Alien films, their face mask shoots out to grab prey and haul it back into their inexpressive jaws. Dragonfly nymphs are truly amazing and totally alien to us. They have subtle and cryptic camouflage, they breathe underwater and they have jet propulsion.

After a couple of years spent eating everything that they can catch in the pond, they get an urge to metamorphosize.  That's not something that us humans can even contemplate. Imagine that you have another being, alive beneath your skin, and that it will burst out from your back, sprout wings and fly away like an angel, even like a god.

That new creature has so many alien features. Most of its head is composed of spherical, compound eyes that can see all around. It has four wings that are synchronised to make it fly like a helicopter or a drone, jinxing sideways, forwards and backwards at high speed. And why? So that it can catch smaller insects, so violently and efficiently that you might hear the click of its cerotein jaws as it snaps up a midge.

Dragonflies are predators, but they are also prey, most spectacularly for hobby falcons that snatch them up on the wing, but also for humble sparrows and rare bitterns that pick them off as they emerge.

So, in utilitarian terms, what are they for?  They have a part to play in the ecosystem that keeps us all alive. They are predators and also prey, eating the insects that we call pests and feeding other animals like birds and fish that we might also consume. But chiefly they are simply inspiring. Without them our world would simply be less inspiring and infinitely poorer. How can I explain any of that to a contemporary young lady who has absolutely no connection the natural world?