Monday, 11 September 2017

Valuing the velvet worm: noticing the most inconspicuous of species

Most of the recent television documentaries or books I've encountered that discuss extra-terrestrial life include some description of the weirder species we share our own planet with. Lumped together under the term 'extremophiles' these organisms appear to thrive in environments hostile to most other life forms, from the coolant ponds of nuclear reactors to the boiling volcanic vents of the deep ocean floor.

Although this has rightly gained attention for these often wonderfully-named species (from snottites to tardigrades) there are numerous other lifeforms scarcely noticed by anyone other than a few specialists, quietly going about their unassuming business. However, they may provide a few useful lessons for all of us, including that we should acknowledge there may be unrecognised problems generated when we make rapid yet radical modifications to local environments.

There is a small, unassuming type of creature alive today that differs little from a marine animal present in the Middle Cambrian period around five hundred million years ago. I first read about onychophorans in Stephen Jay Gould's 1989 exposition on the Burgess Shale, Wonderful Life, and although those fossil marine lobopodians are not definitively onychophorans they are presumed to be ancestral. More commonly known by one genus, peripatus, or even more colloquially as velvet worms, there are at least several hundred species around today, possibly many more. The velvet component of their name is due to their texture, but they bear more resemblance to caterpillars than to worms. They are often described as the ‘missing link' between arthropods and worms but as is usually the case this is a wildly inappropriate term in this context of biological classification. The key difference to the Burgess Shale specimens is that today's velvet worms are fully terrestrial: there are no known marine or freshwater species.

Primarily resident in the southern hemisphere, the largely nocturnal peripatus shun bright light and requiring humid conditions to survive. Although there are about thirty species here in New Zealand, a combination of their small size (under 60mm long) and loss of habitat means they are rarely seen. The introduction of predators such as hedgehogs - who of course never meet peripatus in their northern hemisphere home territory - means that New Zealand's species have even more to contend with. Although I frequently (very carefully) look under leaf litter and inside damp logs on bush walks in regions known to contain the genus Peripatoides - and indeed where others have told me they have seen them - I have yet to encounter a single specimen.

There appears to be quite limited research, with less than a third of New Zealand species fully described. However, enough is known about two species to identify their population status as 'vulnerable'. One forest in the South Island has been labelled an 'Area of Significant Conservation Value' thanks to its population of peripatus, with the Department of Conservation relocating specimens prior to road development. Clearly, they had better luck locating velvet worms than I have had! It isn't just the New Zealand that lacks knowledge of home-grown onychophorans either: in the past two decades Australian researchers have increased the number of their known species from just seven to about sixty.

Their uncanny resemblance to the Burgess Shale specimens, despite their transition from marine to terrestrial environments, has led velvet worms to be described by another well-worn phrase, 'living fossils'. However, is this short-hand in any way useful, or is it a lazy and largely inaccurate term? The recent growth in sophisticated DNA analysis suggests that even when outward anatomy may be change little, the genome itself may vary widely. Obviously DNA doesn't preserve in fossils and so any such changes cannot be tracked from the Cambrian specimens, but the genetic variation found in other types of organisms sharing a similar appearance shows that reliance on just external anatomy can be deceptive.

Due to lack of funding, basic taxonomic research, the bedrock for cladistics, is sadly lacking. In the case of New Zealand, some of the shortfall has been made up for by dedicated amateurs, but there are few new taxonomists learning the skills to continue this work - which is often seen as dull and plodding compared to the excitement of, for example, genetics. Most people might say so what interest could there be in such tiny, insignificant creatures as peripatus? After all, how likely would you be to move an ant's nest in your garden before undertaking some re-landscaping? But as shown by the changing terminology from 'food chains' to 'food webs', in most cases we still don't understand how the removal of one species might generate a domino effect on a local ecosystem.

I've previously discussed the over-reliance on 'poster' species such as giant pandas for environmental campaigns, but mere aesthetics don't equate to importance, either for us or ecology as a whole. It is becoming increasingly clear that by weight the majority of our planet's biomass is microbial. Then come the insects, with the beetles prominent both by number of species and individuals. Us large mammals are really just the icing on the cake and certainly when it comes to Homo sapiens, the rest of the biosphere would probably be far better off without us, domesticated species aside.

It would be nice to value organisms for themselves, but unfortunately our market economies require the smell of profit before they will lift a finger. Therefore if their usefulness could be ascertained, it might help generate greater financial incentive to support the wider environment. Onychophorans may seem dull, but there are several aspects to them that is both interesting in itself and might also provide something fruitful for us humans.

Firstly, they have an unusual weapon in the form of a mechanism that shoots adhesive slime at prey. Like spider silk, is it possible that this might prove an interesting line of research in the materials or pharmaceutical industries? After all, it was the prickly burrs of certain plants that inspired the development of Velcro, whilst current studies of tardigrades (the tiny 'water bears' living amongst the mosses) are investigating their near indestructability. If even a single, tiny species becomes extinct, that genome is generally lost forever: who knows what insights it might have led to? Although museum collections can be useful, DNA does decay and contamination leads to immense complexities in unravelling the original organism's genome. All in all, it's much better to have a living population to work on than rely on what can be pieced together post-extinction.

In addition, for such tiny creatures, velvet worms have developed complex social structures; is it possible that analysis of their brains might be useful in computing or artificial intelligence? Of course it is unlikely - and extinction is nothing if not natural - but the current rate is far greater than it has been outside of mass extinctions. Losing a large and obvious species such as the Yangtze River dolphin (and that was despite it being labelled a ‘national treasure') is one thing, but how many small, barely-known plants and animals are going the same way without anyone noticing? Could it be that right now some minute, unassuming critter is dying out and that we will only find out too late that it was a vital predator of crop-eating pests like snails or disease vectors such as cockroaches?

It has been said that ignorance is bliss, but with so many humans needing to be fed, watered and treated for illness, now more than ever we need as much help as we can get. Having access to the complex ready-made biochemistry of a unique genome is surely easier than attempting to synthesise one from scratch or recover it from a long-dead preserved specimen? By paying minimal attention to the smallest organisms that lie all around us, we could be losing so much more than just an unobtrusive plant, animal or fungus.

We can't save every species on the current endangered list but more attention could be given to the myriad of life forms that get side-lined by the cute and cuddly flagship species, usually large animals. Most of us would be upset by the disappearance of the eighteen hundred or so giant pandas still left in the wild, but somehow I doubt their loss would have as great an impact on the surrounding ecosystem than that of some far less well known flora or fauna. If you think that's nonsense, then consider the vital roles that bees and dung beetles play in helping human agriculture.

Although the decimation of native New Zealand wildlife has led to protective legislation for all our vertebrates and a few famous invertebrates such as giant weta, the vast majority of other species are still left to their own devices. That's not to say that the ecosystems in most other countries are given far less support, of course. But without funding for basic description and taxonomy, who knows what is even out there, never mind whether it might be important to humanity? Could it be that here is a new field for citizen scientists to move into?

Needless to say, the drier climes brought on by rising temperatures will not do peripatus any favours, thanks to its need to remain in damp conditions. Whether by widespread use of the poison 1080 (in the bid to create a pest-free New Zealand by 2050) or the accidental importation of a non-native fungus such as those decimating amphibians worldwide and causing kauri dieback in New Zealand, there are plenty of ways that humans could unwittingly wipe out velvet worms, etal. So next time you watch a documentary on the demise of large, familiar mammals, why not spare a thought for all those wee critters hiding in the bush, going about their business and trying to avoid all the pitfalls us humans have unthinkingly laid for them?

Tuesday, 29 August 2017

Cerebral celebrities: do superstar scientists harm science?

One of my earliest blog posts concerned the media circus surrounding two of the most famous scientists alive today: British physicist Stephen Hawking and his compatriot the evolutionary biologist Richard Dawkins. In addition to their scientific output, they are known in public circles thanks to a combination of their general readership books, television documentaries and charismatic personalities. The question has to be asked though, how much of their reputation is due to their being easily-caricatured and therefore media-friendly characters rather than what they have contributed to human knowledge?

Social media has done much to democratise the publication of material from a far wider range of authors than previously possible, but the current generation of scientific superstars who have arisen in the intervening eight years appear party to a feedback loop that places personality as the primary reason for their media success. As a result, are science heroes such as Neil deGrasse Tyson and Brian Cox merely adding the epithet 'cool' to STEM disciplines as they sit alongside the latest crop of media and sports stars? With their ability to fill arenas usually reserved for pop concerts or sports events, these scientists are seemingly known far and wide for who they are as much as for what they have achieved. It might seem counterintuitive to think that famous scientists and mathematicians could be damaging STEM, but I'd like to put forward five ways by which this could be occurring:

1: Hype and gossip

If fans of famous scientists spend their time reading, liking and commenting at similarly trivial levels, they may miss important material from other, less famous sources. A recent example that caught my eye was a tweet by British astrophysicist and presenter Brian Cox, containing a photograph of two swans he labelled ‘Donald' and ‘Boris'. I assume this was a reference to the current US president and British foreign secretary, but with over a thousand 'likes' by the time I saw it I wonder what other, more serious, STEM-related stories might have been missed in the rapid ebb and flow of social media.

As you would expect with popular culture fandom the science celebrities' material aimed at a general audience receives the lion's share of attention, leaving the vast majority of STEM popularisations under-recognised. Although social media has exacerbated this, the phenomenon does pre-date it. For example, Stephen Hawking's A Brief History of Time was first published in 1988, the same year as Timothy Ferris's Coming of Age in the Milky Way, a rather more detailed approach to similar material that was left overshadowed by its far more famous competitor. There is also the danger that celebrities with a non-science background might try to cash in on the current appeal of science and write poor-quality popularisations. If you consider this unlikely, you should bear in mind that there are already numerous examples of extremely dubious health, diet and nutrition books written by pop artists and movie stars. If scientists can be famous, perhaps the famous will play at being science writers.

Another result of this media hubbub is that in order to be heard, some scientists may be guilty of the very hype usually blamed on the journalists who publicise their discoveries. Whether to guarantee attention or self-promoting in order to gain further funding, an Australian research team recently came under fire for discussing a medical breakthrough as if a treatment was imminent, despite having so are only experimented on mice! This sort of hyperbole both damages the integrity of science in the public eye and can lead to such dangerous outcomes as the MMR scandal, resulting in large numbers of children not being immunised.

2: Hero worship

The worship of movie stars and pop music artists is nothing new and the adulation accorded them reminds me of the not dissimilar veneration shown to earlier generations of secular and religious leaders. The danger here then is for impressionable fans to accept the words of celebrity scientists as if they were gospel and so refrain from any form of critical analysis. When I attended an evening with astrophysicist Neil deGrasse Tyson last month I was astonished to hear some fundamental misunderstandings of science from members of the public. It seemed as if Dr Tyson had gained a personality cult who hung on each utterance but frequently failed to understand the wider context or key issues regarding the practice of science. By transferring hero worship from one form of human activity to another, the very basis - and differentiation - that delineates the scientific enterprise may be undermined.

3: Amplifying errors

Let's face it, scientists are human and make mistakes. The problem is that if the majority of a celebrity scientist's fan base are prepared to lap up every statement, then the lack of critical analysis can generate further issues. There are some appalling gaffes in the television documentaries and popular books of such luminaries as Sir David Attenborough (as previously discussed) and even superstar Brian Cox is not immune: his 2014 book Human Universe described lunar temperatures dropping below -2000 degrees Celsius! Such basic errors imply that the material is ghost-written or edited by authors with little scientific knowledge and no time for fact checking. Of course this may embarrass the science celebrity in front of their potentially jealous colleagues, but more importantly can serve as ammunition for politicians, industrialists and pseudo-scientists in their battles to persuade the public of the validity of their own pet theories - post-truth will out, and all that nonsense.

4: Star attitude

With celebrity status comes the trappings of success, most usually defined as a luxury lifestyle. A recent online discussion here in New Zealand concerned the high cost of tickets for events featuring Neil deGrasse Tyson, Brian Greene, David Attenborough, Jane Goodall and later this year, Brian Cox. Those for Auckland-based events were more expensive than tickets to see Kiwi pop star Lorde and similar in price for rugby matches between the All Blacks and British Lions. By making the tickets this expensive there is little of chance of attracting new fans; it seems to be more a case of preaching to the converted.

Surely it doesn't have to be this way: the evolutionary biologist Beth Shapiro, author of How to Clone a Mammoth, gave an excellent free illustrated talk at Auckland Museum a year ago. It seems odd that the evening with Dr Tyson, for example, consisting of just himself, interviewer Michelle Dickinson (A.K.A. Nanogirl) and a large screen, cost approximately double that of the Walking with Dinosaurs Arena event at the same venue two years earlier, which utilised US$20 million worth of animatronic and puppet life-sized dinosaurs.

Dr Tyson claims that by having celebrity interviewees on his Star Talk series he can reach a wider audience, but clearly this approach is not feasible when his tour prices are so high. At least Dr Goodall's profits went into her conservation charity, but if you consider that Dr Tyson had an audience of probably over 8000 in Auckland alone, paying between NZ$95-$349 (except for the NZ$55 student tickets) you have to wonder where all this money goes: is he collecting ‘billions and billions' of fancy waistcoats? It doesn't look as if this trend will soon stop either, as Bill Nye (The Science Guy) has just announced that he will be touring Australia later this year and his tickets start at around NZ$77.

5: Skewing the statistics

The high profiles of sci-comm royalty and their usually cheery demeanour implies that all is well in the field of scientific research, with adequate funding for important projects. However, even a quick perusal of less well-known STEM professionals on social media prove that this is not the case. An example that came to my attention back in May was that of the University of Auckland microbiologist Dr Siouxsie Wiles, who had to resort to crowdfunding for her research into fungi-based antibiotics after five consecutive funding submissions were rejected. Meanwhile, Brian Cox's connection to the Large Hadron Collider gives the impression that even such blue-sky research as the LHC can be guaranteed enormous budgets.

As much as I'd like to thank these science superstars for promoting science, technology and mathematics, I can't quite shake the feeling that their cult status is too centred on them rather than the scientific enterprise as a whole.  Now more than ever science needs a sympathetic ear from the public, but this should be brought about by a massive programme to educate the public (they are the taxpayers, after all) as to the benefits of such costly schemes as designing nuclear fusion reactors and the research on climate change. Simply treating celebrity scientists in the same way as movie stars and pop idols won't help an area of humanity under siege from so many influential political and industrial leaders with their own private agendas. We simply mustn't allow such people to misuse the discipline that has raised us from apemen to spacemen.