What’s the best [botanical…] use for a 3-D printer?

Not only can you take flowers apart, with a 3D printer you can put together flowers the way YOU want.

Answer: Printing flowers (of course!). But not to display in a florist’s for sale to those who only like to look at them and not smell them (that would work for me and lilies, though. I really can’t abide their so-called scent…) or have to deal with them once they’ve died. Rather, this item is about exploiting the potential of 3-D printing (also known as additive manufacturing) to investigate a scientific problem.

Now, in some corners of academia, scientists are not considered to be creative, enterprising or even imaginative. We don’t subscribe to that blinkered, stereotypical view here. And to prove how erroneous that myopic notion is, scientists* Tobias Policha et al. have shown themselves to be more than a match for the imagination and creativity of their supposedly more enterprising artsy colleagues. The team were aware that flowers of the Ecuadorean cloud forest-dwelling, epiphytic orchid Dracula lafleurii – which grows amongst, and resembles, fungi in shape, colour and scent – were pollinated by small drosophilid flies [related to fruit flies (principally in the genus Zygothrica (Grimaldi, 1987))] that are normally associated with mushrooms. But, what was it about the flowers that attracted the insects: appearance, or odour? Short of ‘creating’ odour-free plants, or spray-painting the flowers different colours – and which would introduce their own problems of interpretation – the ingenious solution was to generate replica flowers.

Using 3-D printing technology they made realistic artificial, but colour-matched, flowers from odour-free surgical silicone to which scent was added. Not only flowers, but also floral parts were fabricated. And, by judicious mixing-and-matching of natural and artificial structures with and without appropriate odours, the team deduced the genus-defining features of Dracula. Which were a mushroom-like, ‘gilled’ labellum and a showy, patterned calyx that enhance the orchid’s pollinator attraction by exploiting the visual and chemosensory perceptual biases of the visiting flies. The paper has another surprise; the abstract’s concluding sentence: “Our techniques for the manipulation of complex traits in a nonmodel system not conducive to gene silencing or selective breeding are useful for other systems”. Understatedly confirming – and contrary to a myth that arabo-overenthusiastic ne’er-do-wells might perpetuate – that you don’t have to limit your botanical studies to model systems! Now, that’s imaginative… and enterprising…

* OK, to be fair, the paper’s authors are a mix of scientists and an artist (third-named author Melinda Barnadas of University of California at San Diego’s Department of Visual Arts and co-founder of Collective Magpie, international art entity). But, I still like to think that it was the scientists with the imagination to collaborate with their more artistic colleague that has led to this most creative and enterprising piece of research…

[Ed. – this paper elegantly builds upon and extends the work of Eric Campos et al. who used 3-D printed ‘representations’ of flowers to investigate moth-pollination preferences. And for more on the relationship between pollinating insects and olfactory and visual cues, check out Natalie de Ibarra et al.]

Further reading

Tobias Policha, Aleah Davis, Melinda Barnadas, Bryn T. M. Dentinger, Robert A. Raguso, Bitty A. Roy, 2016, 'Disentangling visual and olfactory signals in mushroom-mimickingDraculaorchids using realistic three-dimensional printed flowers', New Phytologist, vol. 210, no. 3, pp. 1058-1071 http://dx.doi.org/10.1111/nph.13855

Grimaldi, D. A. 1987. Phylogenetics and taxonomy of Zygothrica. Bulletin of the American Museum of Natural History 186:103–268.

Eric O. Campos, Harvey D. Bradshaw, Thomas L. Daniel, 2015, ' Shape matters: corolla curvature improves nectar discovery in the hawkmoth Manduca sexta ', Functional Ecology, vol. 29, no. 4, pp. 462-468 http://dx.doi.org/10.1111/1365-2435.12378

Natalie Hempel de Ibarra, Keri V Langridge, Misha Vorobyev, 2015, 'More than colour attraction: behavioural functions of flower patterns', Current Opinion in Insect Science, vol. 12, pp. 64-70 http://dx.doi.org/10.1016/j.cois.2015.09.005