On the plane flight home, I feel the afterglow of five weeks of walking on paths in Bornean rainforest, of living smells and stubborn itches, of jumping spider faces looking up at me. So many little faces, so many newly met. I'd never seen a living Hispo before, nor most of the other species we found. It's a wonderful feeling, to have my mind full of all these spiders.
Indulge me, please, as I explain that last comment (mind full of spiders -- wonderful?), and tell you why I am a scientist. When asked about our motivations, we scientists are trained to answer that we're interested in such-and-such conceptually challenging question because of its broad applicability to this-and-that. These are valid answers as to why these studies should be done. These are the reasons resources should be invested in this research. But, is that really why most of us are scientists?
When that Phidippus audax female looked up at me 4 decades ago, I didn't think "Ah, what a perfect study organism to experiment on!" I was, simply, fascinated by her actions, by her reactions to the world around her. I was amazed by her eyes, her metallic green jaws and by the intricately diverse pelage arranged over her body. Seeing her, a whole world opened up, the world of Phidippus audax, as deep and detailed as the world of any species -- dogs, or roses -- but altogether mysterious.
But, it was when I began to look at other jumping spiders that I heard the music. I found other jumping spider species with forms and colors that differed from hers just a bit, or a lot. Her singular nature extended through her colleagues to a melody, to rhythms, variations on a theme full of patterns and yet surprises. As beautiful as an ornamented male salticid may be, ready to dance to the female, what caught my eye were the patterns in diversity. Here is a plate from my doctoral thesis, showing a part of the spider's body and how it appears in each of 35 different species (2 are the same species). Not only is each a small, abstract sculpture, but together the array of them almost dances as my eye moves from one species to the next.
There are moments when I feel I am not a scientist at all, but a curator of the most beautiful art gallery ever assembled. Each species is a work of art. Together, they make the music of diversity.
The static variation of forms we see around us makes but a short moment in this four-billion-years symphonic epic. Now that we know that Life diversified by the splitting of ancestral species repeatedly, genetic lineages branching to form the evolutionary tree of life, we can begin to hear the entire symphony. A single voice, complex in overtones, sings. It splits into two voices, almost the same, but they begin to diverge. And so the voices proliferate into a chorus as the tree of life branches. It would be cacophony, except for three principles. They are all bound by the integrity demanded for survival. They will interact, ecologically, in counterpoint, or dissonance. And, in different parts of the evolutionary tree, voices will stumble on the same melody, converging as they solve life's challenges similarly. The complexity of this evolutionary symphony is overwhelming. But there is pattern, a dynamic pattern, and hence music. This is the beauty of biodiversity. This is why I am a scientist.
Leaving Sarawak, the music of jumping spider diversity is stuck in my head.
Previously in this series:
Text and images © W. Maddison, under a Creative Commons Attribution 3.0 license (CC-BY)