When a pattern in nature emerges, suddenly revealed through new data, I get a high unlike any other. It is this aspect of systematic and taxonomic work that I like the best, which keeps me enthralled, and which I crave whenever I get away from my beetles for too long.
Taxonomists discover patterns. We are cartographers, mapping species and their boundaries. We are often the first people to see the new lands of biodiversity, and it is thrilling to brush away the branches and see, for the first time, a new valley spread out before us, or to get hints of a new island off in the distance, and to have it come into greater clarity as we gather more data. We discover these new species in the field, in the lab, and in museums, and we use as our tools data of all sorts, including (among others) knowledge of the habitats and habits of the organisms as we encounter them in the wild; the structure of the organisms, revealed by careful examination, for my beetles under the microscope; their DNA sequences.
On Friday we received (from the ever-excellent Stacy Sotak at the University of Arizona’s UAGC facility) data for 384 DNA sequences from various species of ground beetles, mostly (of course) Bembidiina. Those 384 sequences are a treasure chest of data about these beetles, and I have spent much of the past two days absorbed with seeing what the sequences reveal, what mysteries they answer, or what mysteries they pose. In the last two days I have discovered that:
- Bembidion gebleri, common and widespread on gravel river shores in western North America, is almost certainly at least two species – there are hints it might be three. And here I have been previously disdainful of B. gebleri, as it is so boringly common! Who knew that several species lurked there! I haven’t looked at the beetles’ structures yet to see if the patterns there match the DNA sequences – that is for later today.
- Bembidion wickhami is certainly at least two species; these two species are even microsympatric, living together on the same creek shore. Wow! (This is worthy of its own post, which I will write shortly.)
- There is a species in the B. (Plataphus) planiusculum group in the Altai mountains of Russia! Dave Kavanaugh sent me specimens of Bembidion from his recent expedition there, and in it was a most curious brown, flat, small-eyed Plataphus. The DNA sequences show that it is a member of the clade I call the B. planiusculum group (including B. planiusculum, B. rufinum, B. gordoni, B. rufinum, B. simplex, and a few others), a group that I had previously only known from North America.
And there’s more, but these three are my favorites (so far – there are still a lot of sequences to look at).
Writing those discoveries down in simple, short prose does not capture the excitement involved in the events – the first initial hint that elicits a “wow!”, the close examination of the data (“really? is it real?”), and, best of all, the realization that two or more different sources of data point in the same direction (“all the ones with that 28S sequence have higher-contrast spots on the body!!!”). The discovery that the pattern is repeated in multiple places (e.g., several different genes, morphological data, geography, habitat) is the best of the best.
Being a scientist is like reading a series of novels, with unexpected crises, resolutions, and moments of calm. There are characters in which we have fallen in love, but not all of them survive, and we become accepting of a changing cast. We have difficulty putting down the book, because the plot is so engaging; sometimes we wish we could turn the page more quickly than we can. And, both to our delight and consternation, we know that the series of novels is endless, and we will never be able to finish the last page, close the book, and set it down.
If scientists had video cameras trained on them as they made their discoveries, the passion and joy that would be evident would surely excite many a child into becoming a scientist. Perhaps when the next batch of my sequences arrive in a few weeks… In the meantime, enough writing – I need to look at those sequences more! And I need to look at those specimens I took to all be B. gebleri, to see if I can see morphological patterns!