What is the most important part of a scientific paper? Arguably, it’s the Results section– although there are those who might propose that it’s the authors (scientists after all are humans and appreciate having their names associated with the science – especially if it is deemed to be first-rate and published in a high impact journal). But, there is one section that’s deemed to be of such unimportance that it’s not worthy of scrutiny during peer review and usually survives intact as the authors intended. And that section should never be overlooked in reading a paper because, although it’s not the most important, it can often be the most revealing in terms of the background or context to the work that’s detailed elsewhere in the article. That section is the Acknowledgements, which comes into its own in papers such as that by Stephanie Crofts and Philip Anderson on cactus form-and-function.
Investigating how “the influence of cactus spine surface structure on puncture performance and anchoring ability is tuned for ecology”, the enterprising duo examined the puncturing and anchoring ability of the spines of six species of cactus. Why?
Well, according to the Introduction, cactus spines appear similar to porcupine quills, and, since the biomechanics of the latter as defensive mechanisms have been previously tested, but those of the former have not, they thought it was about time that the plant-like porcupines are subject to the same degree of scrutiny. Which all seems like sufficient justification to me.
They duly carried out the necessary tests which included perforating chicken and pork products with cactus spines to test such important properties as the plant protuberances’ penetrative power, and difficulty in their removal (for a graphic image of this technique, see Jennifer Leman’s article).
I won’t give away the results here because this news item is really about the Acknowledgements section, that oft-overlooked gem of science writing (which so often reveals the science practitioners human side). It is often said that artists suffer for their art; seemingly, both Croft and Anderson suffered for their science as we can infer from the last sentence of the paper’s Acknowledgement, which simply states “Finally, we thank the makers of the Swiss Army Knife for including tweezers on their classic knife.” Ouch!*
* A less painful piece of cactus-related research is provided by Chang Li et al. who report the “fog harvesting of a bioinspired nanocone-decorated 3D fiber [sic.] network”. Inspired and informed both by spider webs and cactus spines they’ve developed a structure that can effectively harvest water from fog (“tiny water droplets suspended in the air”). Although the specifics of this biomimetic solution may differ to that found in nature, the overall effect and mechanism is similar to water-abstraction by desert-dwelling plants in arid, but fog-frequented, places world-wide.
An aspiration for the work is that it will be of benefit as part of an agricultural irrigation system in water-deficient countries, where fog-collection schemes** are being considered as ways of alleviating water-scarcity issues. For more on the moisture-harvesting abilities of plants – and animals (we must keep the zoosensitive readership happy), we recommend Malik et al.’s topical review.
** The ever-mischievous Mr Cuttings wonders if this was actually predicted last millennium, by ‘Tyneside’s favourite band’ Lindisfarne in their song ‘Fog on the Tyne’. Everybody interprets the last word to be the name of the mighty river Tyne in the north-east of England. Maybe we’ve been getting it wrong all these years. What if the ‘tyne’ referred to is in fact tine, the name for a prong of a fork? Which ‘pointy thing’ can be likened to a … cactus spine. However, and much like the issue with the quatrains of Nostradamus, it’s only after an event has come to pass that any ‘prediction’ can be understood. Which makes it little use as a prediction. Sorry, this is just ‘end-of-term’ foolishness from Mr C – the reason for which is provided by the next, final, plant cutting.
Crofts, S. B., & Anderson, P. S. L. (2018). The influence of cactus spine surface structure on puncture performance and anchoring ability is tuned for ecology. Proceedings of the Royal Society B: Biological Sciences, 285(1891), 20182280. https://doi.org/10.1098/rspb.2018.2280
Li, C., Liu, Y., Gao, C., Li, X., Xing, Y., & Zheng, Y. (2019). Fog Harvesting of a Bioinspired Nanocone-Decorated 3D Fiber Network. ACS Applied Materials & Interfaces, 11(4), 4507–4513. https://doi.org/10.1021/acsami.8b15901
Ju, J., Bai, H., Zheng, Y., Zhao, T., Fang, R., & Jiang, L. (2012). A multi-structural and multi-functional integrated fog collection system in cactus. Nature Communications, 3(1). https://doi.org/10.1038/ncomms2253
Pan, Z., Pitt, W. G., Zhang, Y., Wu, N., Tao, Y., & Truscott, T. T. (2016). The upside-down water collection system of Syntrichia caninervis. Nature Plants, 2(7). https://doi.org/10.1038/nplants.2016.76
Sharma, V. Balaji, R. & Krishnan, V. (2018). Fog-Harvesting Properties of Dryopteris marginata: Role of Interscalar Microchannels in Water-Channeling. Biomimetics 3 (2), 7. https://doi.org/10.3390/biomimetics3020007
Malik, F. T., Clement, R. M., Gethin, D. T., Krawszik, W., & Parker, A. R. (2014). Nature’s moisture harvesters: a comparative review. Bioinspiration & Biomimetics, 9(3), 031002. https://doi.org/10.1088/1748-3182/9/3/031002