Science: for the sheer fun of it!
Despite frequently expressed assumptions to the contrary, science – whether it's botany or some lesser intellectual pursuit – isn't always about having an idea and undertaking an experiment to test it. Anyway, that type of investigation can be hard work. Fortunately, there is an alternative approach that basically studies ‘what's there’ and muses on why that might be (or not …), so-called blue skies research[1]. Sadly, the latter type of science – which I think is much more fun and interesting – is less likely to get financed than the ‘there's a definite question that we aim to answer’ type of study, and is generally much less common. Nice then to see that, in conversation with Sarah Williams in the Howard Hughes’ Medical Institute's Fall 2013 issue of the HHMI Bulletin[2], Dr Richard Flavell (Sterling Professor of Immunobiology at Yale School of Medicine[3]) promotes the view that observation-driven studies have a place in science. He goes further in saying that, ‘there's nothing wrong with a lab team doing observational study after observational study. They are still helping advance the science, and likely providing fodder for hypothesis-driven studies to come …’. Now that is my kind of science. I do hope those who fund research are listening to – and heeding – this! Unfortunately, I suspect the more usual reaction to requests to finance such work from the grant-awarding bodies would be similar to that which prompted this acknowledgement in a scientific paper: ‘I thank the National Science Foundation for regularly rejecting my (honest) grant applications for work on real organisms (cf. Szent-Gyorgyi, 1972) …’[4] (from Leigh Van Valen's* paper, ‘A new Evolutionary Law’[5]. But occasionally studies along the lines of ‘let's just see what turns up’ do appear. Take, for example, Michael Proctor and Margaret Bradshaw's first in a planned series of papers on scanning electron microscopy (SEM[6]) examination of leaves of British sedges in New Journal of Botany**[7]. Acknowledging that the ability to identify sedges in the field is important to many vegetation studies but recognising that inflorescences are available for only a short period each year, the pair have concentrated on SEM studies of leaf surfaces to assist those identification endeavours. Whilst the duo don't advocate taking a SEM into the field, they do believe that such SEM studies will be ‘useful in putting leaf characters on a firmer footing, and drawing attention to characters which could be useful for identification with a hand-lens or low power microscope’ (which can be taken into the field …). The images need to be seen to be properly appreciated, but the imaging of epicuticular waxes in, for example, Figure 1f attests to their high quality. Bring on Part 2! [For those expecting to read about ‘botanist’ Richard Flavell PhD, FRS, CBE, former Director of the John Innes Centre, etc.[8], I'm sorry to ‘disappoint’ – Ed.] * Leigh van Valen is an American evolutionary biologist probably best known for the Red Queen Hypothesis[9]. ** This is the official organ of the BSBI, the leading society in Britain & Ireland for the study of plant distribution and taxonomy[10]. The Botanical Society of Britain and Ireland was formerly called the Botanical Society of the British Isles, and represents a name change every bit as slick as that of the WWF (which changed from World Wildlife Fund to World Wide Fund for Nature in 1986[11]) and which also allows it to keep its abbreviation of BSBI (which is an initialism not an acronym[12]) the same.
Image: Robert Hooke, 1665. Micrographia. Jo. Martyn and Ja. Allestry, London.
[1] http://en.wikipedia.org/wiki/Blue_skies_research; [2] http://bit.ly/1lKj0e2; [3] http://www.hhmi.org/scientists/richard-flavell; [4] http://slate.me/1eeX9IC; [5] Evolutionary Theory 1: 1–30, 1973; [6] http://bit.ly/1gAQ1J7; [7] New Journal of Botany 3: 197–204, 2013; [8] http://reut.rs/JDul3q; [9] http://en.wikipedia.org/wiki/Leigh_Van_Valen; [10] http://www.bsbi.org.uk/; [11] http://bit.ly/197OASw; [12] http://en.wikipedia.org/wiki/Acronym.
Caught in the act …
Examples abound of ancient life forms trapped in suspended inanimation within amber (fossilised tree resin[1]) and which give us clues about ancient – maybe even extinct – biota and their ecology (e.g. ‘The past is bright, the past is … amber’[2]). A revelation concerning amber-encased plant material suggests that current sexual reproduction in angiosperms may have remained little changed in over 100 million years. This insight comes from a new, albeit extinct, species named Micropetasos burmensis and work by George Poinar et al.[3] with amber deposits from the mid-Cretaceous in Burma (Republic of the Union of Myanmar[4]). Although given a binomial (with a formal description in English, as now permitted[5]) and clearly a flowering plant, the team ‘prefer to leave the question of its exact familial relationships open at this time’. However, arguably the most interesting aspect of this discovery is the sight of pollen tubes growing out of two grains of pollen and penetrating the flower's stigma (the receptive part of the female reproductive system[6]). This precedes fertilisation of the egg, which would have begun the process of seed formation[7], had this act of plant coitus not been interrupted. Curiously, this is not mentioned explicitly in the journal article, but was only discerned in the press release promoting it[8]. Was that statement too outrageous or speculative for inclusion in the journal article? Surely not; legitimate commentary such as this ought to be encouraged, and only serves to make the discovery even more interesting. Come on, lads, don't hide your light under a bush(-el)[9] … [OK, you can relax, I've saved you the trouble of finding that story about 165-million-year-old fossil insects caught during copulation. Text – and pictures – at the Smithsonian's website[10] – Ed.]
Image: Marie Majaura/Wikimedia Commons.
[1] http://en.wikipedia.org/wiki/Amber; [2] Annals of Botany 105(6): vi, 2010; [3] Journal of the Botanical Research Institute of Texas 7(2): 745–750, 2013; [4] http://en.wikipedia.org/wiki/Burma; [5] PhytoKeys 5: 1–3, 2011; [6] http://bit.ly/1gbBuCK; [7] http://www.sciencedaily.com/articles/s/seed.htm; [8] http://bit.ly/Kwalkh; [9] http://bit.ly/19XhYZQ; [10] http://bit.ly/JDDUzz.
A positive plethora of plant papers!
Unusually for this column (why give the ‘competition’ a free bit of publicity, after all?), I here wish to promote The Scientist magazine[1]. As a general science news item site it occasionally features plant-related items, but it has surpassed itself with its 1st January 2014 collection[2]. Not only does it feature a wonderful image of the fruit of the lotus plant on its cover, but it also contains four big plant articles(!!!). By way of introducing that compilation, Mary Aberlin observes in her editorial[3] that, ‘the panoply of fictional plants offers a large and varied dose of the weird and wonderful. But there's no need to resort to fiction to find truly unusual plant characteristics’… so, read on! Accordingly, the selection comprises an item by Abby Olena that considers halotropism, a newly identified tropism in roots[4]. This showcases a study by Carlos Galvan-Ampudia et al. that demonstrates active growth of roots of several plant species away from sites of high salt content, and which is not gravitropism[5]. This work begs the question of how many other tropisms might still await discovery in that understudied plant organ. In ‘Green gold’ Tracy Vence reports on the discovery of gold bioaccumulation in eucalyptus leaves[6], which was covered in our very own Plant Cuttings item ‘Money doesn't grow on trees … (2) [Or, From cuddly koalas to bird poo …]’[7]. Megan Scudellari's article[8] begins by posing the question, ‘What do cells, genes, mutations, transposons, RNA silencing, and DNA recombination have in common?’: the answer – but, of course! – is that all were first discovered in plants; she then considers how plant DNA is challenging preconceptions about the evolution of life (including our own species). And Dan Cossins considers the question of whether plants ‘talk’ to each other[9]. Reviewing a wide-ranging body of work, the conclusion is that plants do communicate and interact with each other, both above and below ground, in surprisingly subtle and sophisticated ways. And by way of demonstrating how the time is right for certain ideas, Kat McGowan has an item in Quanta Magazine on ‘The secret language of plants’[10]. Almost inevitably these sorts of articles raise the spectre of how intelligent plants are, and that issue is given a good airing in Michael Pollan's New Yorker article[11]. What a great botanical start to the New Year! [Visit YouTube for a documentary on plant intelligence[12] and also if you want to know what plants talk to each other about[13] – Ed.]
Image: Ryan Kitko/Wikimedia Commons.
[1] http://www.the-scientist.com/; [2] http://bit.ly/1lKAlDs; [3] http://bit.ly/1lKApDh; [4] http://bit.ly/1gAY0G3; [5] Current Biology 23: 1–7, 2013; [6] http://bit.ly/JYm4H8; [7] Annals of Botany 112(9): vi, 2013; [8] http://bit.ly/1cTjTQg; [9] http://bit.ly/1iJCfHh; [10] http://bit.ly/1cTk0eL; [11] http://nyr.kr/1da9p0N; [12] http://bit.ly/1cTk7qO; [13] http://bit.ly/1lKARRO.
Everything benefits from a little lift
Roots generally absorb water from the soil and transport it above ground to the stem, branches, etc. Where the soil is too dry for water to be absorbed by the roots, the roots might actually lose water to the soil and risk being damaged if that situation persists. However, in some arid conditions where upper soil water levels may be very low and near-surface roots could otherwise subsequently become damaged, water absorbed by roots at depth may be transported upwards and released through those near-surface roots into the soil that surrounds them at night-time[1]. During the following day that root-released water is taken up and transpired from those shallower roots. This phenomenon is known as hydraulic lift (HL[2]) and can have substantial benefits to the plant doing the lifting (e.g. greater daily carbon gain, increased growth and increased nutrient uptake); in a coincidentally altruistic way, HL may also benefit neighbouring plants[3]. It has also been postulated that HL might enhance nutrient availability to plants by stimulating microbially controlled nutrient cycling; experimental support for which notion has now been provided by Zoe Cardon et al.[4]. Working with sagebrush (Artemisia tridentata var. vaseyana), the team not only demonstrated increased rates of nitrogen cycling in surface soil layers around plants where HL was permitted, but also increased uptake of nitrogen into their inflorescences as seed was set. Or, in the words of John Stark (one of the study's co-authors and professor at Utah State University's Department of Biology and Ecology Center), ‘What we're discovering is, through a process called hydraulic lift, plants also leak water into the bone-dry surface soil to release nutrients and stir microbial activity critical to the plants’ survival’[5]. All of which just goes to show that whenever presented with a problem, Nature usually finds an elegant, even uplifting, solution. Sage bush, that there sagebrush. [HL is nowadays better replaced by the term hydraulic redistribution[6], since it can occur/take place upwards (HL) and/or downwards (hydraulic descent); see, for example, Kevin Hultine et al.'s article ‘Hydraulic redistribution by deep roots of a Chihuahuan Desert phreatophyte’[7]. For a review of water release through plant roots, see Iván Prieto et al.'s New Phytologist article[8] – Ed.]
Image: Wikimedia Commons.
[1] http://bit.ly/1f8ztLj; [2] http://bit.ly/1cHqclC; [3] Trends in Ecology and Evolution 13: 232–235, 1998; [4] PNAS 110: 18988–18993, 2013; [5] http://bit.ly/1f8zI94; [6] http://bit.ly/1cTpOoE; [7] Tree Physiology 23: 353–360, 2003; [8] New Phytologist 193: 830–841, 2012.
Your botanical ‘one-stop shop’
There are plant biology journals that seem to concentrate on a single taxon (you know the ones I mean!) – e.g. The Plant Journal[1] and The Plant Cell[2]. There are others devoted to the molecular biology of plants, such as the aptly named Plant Molecular Biology[3], and to plant physiology, such as the equally aptly named Plant Physiology[4]. And all do good things. But for my mind the best general plant biology (in the best traditions of botany, from sub-cellular events to ecosystems via such sub-disciplines as anatomy and physiology) journal is still the Annals of Botany[5]. Now I might be biased – after all, it published my very first foray into science publication[6], I am a Handling Editor for the journal, and it hosts this monthly column – but it's still the longest-running (founded in 1887[7]), and arguably the best of its kind. OK, the New Phytologist[8] comes a close second – and contains some very good items (some of which have been showcased in this very column over the years – e.g. ‘Soil → roots → stem → atmosphere …’[9]) – but I still associate it with pollen diagrams, mycorrhiza and effects of ozone on plants (yes, I know it's changed somewhat, but that is how it appeared to me in the 1970s and 1980s …). So what is the special appeal of the ‘Original Phytologist’? It's just that its coverage is so wide and every issue has items of interest to those who like to maintain a broad appreciation of plant biology/botany. Take, for instance, the January 2014 issue, which – for me – has at least five items of note: Chong Wei Jin et al's review ‘An underground tale: contribution of microbial activity to plant iron acquisition via ecological processes’[10]; and the research articles of Andrej Pavlovič et al., ‘Feeding on prey increases photosynthetic efficiency in the carnivorous sundew Drosera capensis’[11]; Melanie Horbens et al., ‘Ontogenetic tissue modification in Malus fruit peduncles: the role of sclereids’[12]; Katerina Koutsovoulou et al., ‘Campanulaceae: a family with small seeds that require light for germination’[13]; and Bo Hu et al., ‘Root cortical aerenchyma inhibits radial nutrient transport in maize (Zea mays)’[14]. All of which have stories to tell, and are informative and also educational: each contributing to the bigger picture that is an appreciation – if not yet a full understanding – of the life of the green plant. Whilst few, if any, of these articles are likely to be cited in my own papers (that is not the sort of botany my own scholarly activity covers these days), they all stand a very good chance of featuring in lectures to my undergraduates. And all of these articles are firmly in keeping with the educational remit of the journal's owners (the Annals of Botany Company), ‘To promote the science of botany …’[7]. So whether you are a botanical educator or researcher (or both!), if you haven't yet tried the journal, why not? i.e. do read past the journal's front matter such as these Plant Cuttings, the ContentsSnapshots and book reviews and dip into the research articles, invited reviews, etc. – you might even enjoy it. But, be warned, the Annals of Botany can be habit-forming (though not all habits are bad for you …). Happy reading!
Image: Hu et al., 2014. Annals of Botany 113: 181–189.
[1] http://bit.ly/1eCnoJK; [2] http://www.plantcell.org/; [3] http://link.springer.com/journal/11103; [4] http://www.plantphysiol.org/; [5] http://aob.oxfordjournals.org/; [6] Annals of Botany 50: 717–720, 1982; [7] http://annalsofbotanycompany.com/about; [8] http://bit.ly/1dqpqKF; [9] Annals of Botany 112(3): iv, 2013; [10] Annals of Botany 113: 7–18, 2014; [11] Annals of Botany 113: 69–78, 2014; [12] Annals of Botany 113: 105–118, 2014; [13] Annals of Botany 113: 135–143, 2014; [14] Annals of Botany 113: 181–189, 2014.