Note: This is a science outreach piece belonging to a series I wrote for the newsletter of the Fredericton Botanic Garden. I’d be happy to see it modified for use elsewhere and so am posting the text here under a CC BY-SA 4.0 license. If you use it, though, I’d appreciate hearing where and how.
I went for a walk in the Garden last week, and it was lovely to see the colours on display – nature in all shapes and sizes, with another species offering a different look everywhere I turned. I’m not talking about the flowers – although those were nice too. I’m talking about our Garden of Insects.
The Garden of Insects isn’t a signed attraction. It’s not something we built, or even intended. It’s just the way nature is: insects are everywhere. That’s not a bad thing: insects are beautiful, and important, and fascinating. (They don’t deserve the fear and disgust they sometimes provoke. OK, perhaps most of could agree that mosquitoes aren’t our favourite neighbours on the planet, but close up even they are surprisingly beautiful). In the Garden on any given day you might see a brilliantly-coloured butterfly flitting across a bed, a striped and industrious bumblebee pushing deep into a flower in search of pollen, or a busy team of ants tending the planthoppers they farm. You might see ladybeetles hunting aphids on the leaves of your favourite plant – while aphid mothers, incredibly, give birth to aphid babies already swollen with their aphid grandbabies. You might see the tunnels left by leafmining fly larvae chewing their way through just the middle layers of a leaf – tunnels that grow wider as the larvae grow, as if you spent your childhood burrowing through the white filling of a giant Oreo cookie, eating as you went.
You might think I was making this stuff up, but I’m not. Any way you can possibly imagine of making a living – and many ways you probably can’t – has been taken up by some insect, somewhere. This is partly because of evolution’s power to solve problems in unexpected ways. It’s also partly because insects are so astonishingly diverse.
I’m not sure how many plant species there are in our Garden – perhaps a few hundred, counting both planted and wild species. (New Brunswick has about 2000 plant species; worldwide, the figure is about 250,000). The Garden has a handful of amphibians and reptiles, perhaps a dozen mammals, and likely a hundred or so bird species. But insects? It’s hard even to guess. If my back was to the wall, I might say 1,200 insect species in the Garden, perhaps 20,000 for New Brunswick; but I wouldn’t be at all surprised if the real numbers were double that.
Actually, that might be the most surprising thing about insects: that we don’t know, even to a rough approximation, how many species we share our planet with. About a million different species of insects have been identified by scientists worldwide, but estimates of how many remain to be discovered run the gamut from another 2 million to, believe it or not, 300 million! And while many of the undiscovered marvels are waiting for us in the depths of unexplored rainforests, there are sure to be species new to science here at home – even in the Garden. Work done by postdoc Julia Mlynarek in my laboratory, for example, recently showed that flies emerging from leaf mines on the goldenrod pictured above belong not to one species (Ophiomyia quinta) but two (O. quinta and a species not yet named). That’s a small advance, granted; but DNA sequencing we’re doing now may reveal a few more new species or dozens, and that’s just among leafminers attacking a few species of goldenrods and asters.
So on your next trip to the Garden, by all means enjoy the flowers. But don’t stop there. With a little bit closer look there’s a lot more to see, with an insect story on every flower, behind (or inside) every leaf, and under every log. Take advantage of our Garden of Insects!
© Stephen Heard (email@example.com) July 18, 2016, but licensed CC BY-SA 4.0..
Other Botanic Garden newsletter outreach pieces):