Diversity and extinction of tongues and species

Some years ago, at a rather posh function in a swanky London venue, I got talking to a peer of the realm. By this point I had been drinking my endless glass of wine for some time (they have stealthy waiters at these kinds of dos), and didn’t quite catch his name, but he had been, apparently, head of a large supermarket chain. And his response to me mentioning the word ‘biodiversity’ has stuck with me. “When I took over at M&S”, he said - or was it Morrisons, or maybe Sainsbury’s? - “I noticed that we stocked loads of different kinds of tomatoes. I said that we should just stock one kind, but make sure it was a fucking good tomato. I sometimes think the same about biodiversity: focus on just a few species, but make sure they are fucking good species.”

Well, an interesting take I suppose, and perhaps the logical outcome of a purely utilitarian approach to nature. But not, I submit, a view that would go down well with many conservation groups. No place in this world for God’s own prototypes, the weird and the rare never considered for mass production. No place for a grass-powered bear reluctant even to reproduce, or a fish content to spend its entire life in a tiny pool.

So anyway I filed away the anecdote, to be dusted off from time to time when the occasion arises. But I got to thinking about it again just recently, after reading the excellent Lingo: A language-spotter’s guide to Europe by Gaston Dorren. Over 60 brief chapters, this book provides pen portraits of dozens of European languages, from the behemoths of English, German, and French to tiddlers like Manx, Monegasque and Sorbian. It is full of fascinating nuggets, such as the plural for the Welsh word cwm being (naturally) nghymoedd. There are also examples of useful words that English might consider - the German Gönnen, for example, “the exact opposite of ‘to envy’: to be gladdened by someone else’s fortune.” Interesting that we happily adopted Schadenfreude but not this… Other favourites include the Dutch Uitwaaien, to relax by visiting a windy, chilly, rainy place; the Sorbian Swjatok for the enjoyable hours that follow the end of the working day; the wonderful Greek Krebatomourmoúra, “similar in meaning to ‘pillow talk’ but with a greater element of discord”; and the Slovene Vrtičkar, “strictly speaking no more than a hobby gardener with an allotment, but the word also suggests that the person is more interested in spending time with other vrtičkars than in growing vegetables and flowers.”

More than these fun pieces of trivia, however, the book gives a valuable overview of the languages and people of my home continent, including useful tips - tricks to identify written languages, a primer in the cyrillic alphabet - as well as a potted history of conquest and subjugation. But it is also a study of loss: of the extinction and near extinction (and, more positively, occasional resurrection) of our continent’s linguistic diversity.

The parallels with biological diversity are striking, and of course I am not the first to make them. Indeed this lovely paper by Tatsuya Amano and colleagues  actually presents a full macroecological analysis of the world’s 6909 languages, formally assessing extinction risk based on the same criteria that the IUCN use to assess species. They show that around a quarter of all languages are threatened based on a small ‘range’ or population sizes (spoken in an area of less than 20 square kilometres, or by fewer than 1000 people), or an alarming rate of decline. Their maps showing hotspots of diversity and threats, and their analyses of drivers of change, also have a familiar look to those of us more used to examining spatial patterns in biodiversity.

Of course this seems sad, just as the loss of diversity within languages is also troubling, as we lose the ability to express uniqueness of place and of our connection with the landscape. But the thing with language is that it is so personal - especially for me, now, watching my kids go through the endlessly fascinating process of acquiring it. And so whereas I unequivocally want to prevent the extinction of species, as far as languages go - well, a little part of me agrees with the good Lord above. Diversity is great in theory, but in practice…? Basically, I want my kids to learn a fucking good language.

Happily, at this point in time, I have no conflict to resolve: English, for better or worse, is just such a language. But what if I’d got that job in north Wales a few years back? Not only might I have had to contend with the frankly unthinkable proposition of children on mine shouting for Wales in the Six Nations, what about the possibilities for mischief opened up by kids speaking a language I can’t understand? And while bilingualism has many advantages, wouldn’t it be kinder to your kids to have them fill the ‘second language’ part of their brain with something more ‘useful’? Spanish or Mandarin or something else that opens up new parts of the world to them?

No doubt this attitude arises in part from my monoglot culture, beautifully captured in the Eddie Izzard quote with which Dorren begins his book, “Two languages in one head? No one can live at that speed! Good Lord, man, you’re asking the impossible!” On the contrary, learning two, three, four languages seems perfectly possible in many parts of the world. But for those seriously threatened languages, well, keeping them alive - truly alive, not simply remembered - means that some people’s children have to learn them. And I can’t help wondering: is that really fair?

Mixed messages on Marine Protected Areas

I can’t remember the details of the first scientific conference I ever went to - not even its name - but I know it was on marine conservation, in Cardiff, and that a couple of us undergrads had made the trek from Norwich with little idea what to expect. The keynote speaker was Bill Ballantine, some of whose work on Marine Protected Areas (MPAs) in New Zealand I’d read as research for an essay. I remember no details of his talk, other than it adding to my general opinion of MPAs as a Good Thing; more memorable was his (grumpy, admirable) single word response - “No” - to a lengthy question from the floor. Anyway, this came back to me recently when I saw a new paper from Ballantine, giving a 50 year New Zealand perspective on MPAs. In particular, he suggests that the struggle to convince people of the worth of MPAs elsewhere could be greatly reduced by using New Zealand’s long (and ultimately successful) experiment as an exemplar. As it happens, another eminent MPA researcher, Timothy McLanahan, has also just published an analysis of the effectiveness of Kenyan MPAs based on data going back almost as far. These long-term perspectives give some context to the latest marine planning developments in the UK, where we are slowly (too slowly according to many voiciferous campaigners, not least Hugh Fearnley-Whittingstall, whose latest Fish Fight aired last week) progressing towards a network of marine conservation zones (MCZs). Campaigners disagree with other marine stakeholders over how much evidence is needed in order to establish these MCZs, and tempers can get rather frayed (not helped by the use of the word ‘Fight’ in the campaign; see my post from last year) - although there has been a certain rapprochment over the last year (this fishing industry view, for example, seems quite conciliatory to me and is hardly ‘anti conservation’).

So any evidence about the effectiveness of MPAs is to be welcomed, and a new study by Graham Edgar and colleagues published recently in Nature provides the most comprehensive review to date. Let me say at the outset that this is an enormously impressive piece of work: the team surveyed almost a thousand reefs from 87 MPAs and another thousand or so non-protected sites, from 40 countries around the world, using a standard methodology, their coverage allowing systematic comparisons of protected and non-protected areas using neat statistical methods. Their decision to concentrate on reefs, and on reef fish in particular, was both sensible - in that most MPAs are on reef systems, and reef fish are especially well studied - and necessary in order for the study to be feasible. It seems almost churlish to note that the 8000 or so reef fish species constitute 3-4% of described marine species, and perhaps just 1% of all marine species; but it is important that we bear this in mind when interpreting their conclusions: we have far less quantitative data on the effectiveness of MPAs for the groups constituting the majority of marine biodiversity.

Nevertheless, the scope of this study was broad enough that certain generalisations emerged. In particular, the authors were able to identify five factors that are key to the conservation success of an MPA. (“Success” here is defined using various measures including numbers of all fish species, numbers of species in key groups such as sharks, biomass of all fish, and of large fish.) These factors they term NEOLI, for No take (no fishing allowed), Enforced (effective enforcement of regulations), Old (long-established), Large (in terms of the area protected), and Isolated (separated from similar habitat by an extent of deep water or sandy substrate). They found that MPAs possessing four or five of these attributes score markedly higher than non-protected areas, particularly for total fish biomass, large fish biomass, and shark biomass. But MPAs with one or two NEOLI characteristics only were ecologically indistinguishable from unprotected sites.

And here’s where the mixed messages begin, in terms of the effectiveness of MPAs as a conservation strategy. First, across their entire dataset only four MPAs had all five NEOLI characteristics. Just five more had four characteristics. In other words, although MPAs can be very effective at achieving conservation objectives for reef fish, hardly any actually are. And as the authors say, “The low proportion of MPAs possessing four or five NEOLI features (10%), and thus regarded here as effective, probably overstates the true proportion of effective MPAs worldwide. Our survey strategy deliberately targeted well-known and well-regarded MPAs, with most large and long-established MPAs included in this study.” This is sobering indeed.

But the second mixed message is rather more subtle. Many proponents of MPAs talk them up as ‘win-win’. That is, MPAs are good for both conservation and for fisheries, largely because fish populations can build up within a reserve and then ‘spill over’ to the surrounding area, where they can be fished. This is certainly an argument I've made in the past. Yet the ‘I’ of NEOLI stands for Isolation, precisely because Isolation avoids spillover, so that protected fish stay within the MPA - in other words, an Isolated MPA specifically excludes the “presence of continuous habitat allowing unconstrained movement of fish across MPA boundaries”, which is exactly what MPAs are supposed to deliver to surrounding fisheries. Thus, one of the major contributors to the success of an MPA in conservation terms, is that it does not benefit fisheries.

This is, I think, extremely pertinent to the current debate within the UK, where conservation outcomes of MPAs are often conflated with other potential outcomes. The danger here is that we end up with reserves that are suboptimal for all objectives. As in all conservation initiatives, it is much better to have specific, measurable objectives defined at the outset, so that the effectiveness of any intervention can be properly assessed. Scientific evidence has a key role in this planning process, and - frustrating as it feels - this can take time. Isn’t it worth taking just a bit more time now, to ensure our seas are properly - and effectively - protected for future generations?

On endlings and singletons

There can be few words as poignant as ‘endling’, the name given to the last surviving individual of a species. Tell me you don’t find this image of Benjamin, the last Thylacine, heartbreaking? Or that you weren’t moved by the plight of Lonesome George? And what about Martha, the passenger pigeon? Doesn't her story make you weep at our limitless environmental profligacy? But what links all of these endlings is that we know they were once members of a thriving population - in Martha’s case, one of the most abundant vertebrate species on the planet. There are other species which are known only from a single individual. These species, perhaps lacking the poignancy of endlings but arguably more significant to students of biodiversity, are known as 'singletons'.

Singletons of course are to be expected when your survey area is small, or if your look for only a short period of time. If I counted the birds in my garden for an hour tomorrow morning, I’d expect to see multiple individuals of a few species - magpies, wood pigeons, house sparrows - but I’d be very surprised to see more than one sparrowhawk or wren. However, if I extended my search to my whole street, or to the whole of Sheffield, the number of singletons would drop off precipitously. And at the scale of the UK, over the course of an entire summer, any breeding bird species by definition must be represented by at least two individuals, so there should be no singletons at all in our core avifauna. Any that remain can be dismissed as shivering vagrants blown across the Atlantic, ornithological curiosities but ecologically insignificant.

Enter the sea, though, and the number of singletons remains stubbornly high, even when we expand enormously our study region. For instance, in an analysis of European benthic invertebrates I did a few years ago, I found that about 10% of the species in our very large database (2,300 species sampled from >15,000 locations throughout European seas) were singletons. Similar patterns appear when interrogating the Ocean Biogeographic Information System database I blogged about recently. For instance, OBIS contains records for >11,500 species occurring in the seas around Britain, yet over 45% of these are represented by a single record. At the global scale, 20% of the almost 80,000 marine animal species which occur in OBIS are singletons.

What's happening here? Are these singletons simply very rare species? We expect most species to be rare, but do our surveys of marine habitats really cover so small an area that we never pick up their conspecifics? And if this is so, what does this mean for marine ecosystem functioning? Do these rare species play a role? Individually, maybe not - Kevin Gaston has written on the dominance of common species in terms of numbers, biomass, and probably ecosystem functioning, in most communities. But collectively the singletons in a sample can be abundant, and if there were particular biological characteristics associated with being a singleton, then this could be significant. Unfortunately, about the one generalisation we can make about rarely observed marine species is that we know little about their biology, so we’re not yet in a position to answer this question.

An alternative explanation is that many singletons are mistakes. When analysing diversity surveys, we can take steps to ensure that taxonomic names are consistent, for instance by using the World Register of Marine Species to ensure that we use the accepted name for each species and not one of its (often many) synonyms (I've done that in the cases mentioned above). But what if the person who sorted the sample simply got their identification wrong? There’s not much we can do about that kind of mistake, although one would hope that errors of identification are not so frequent as to explain the very high prevalence of singletons.

Probably we won’t know the answers to such questions until sampling of a few large marine ecosystems reaches a sufficient intensity that we can have confidence that surveys accurately reflect the composition and relative abundance of the species present. For now, we can at least use the presence of singletons to tell us something about how far away from such complete knowledge we are. As I suggested in my last post, in certain marine systems the answer to this is: a very long way indeed. In the meantime, we are becoming more and more aware of the threats facing many marine species. We must hope that the singletons we find in our surveys are only statistical loners, the first observed rather than the last remaining individual. If they do in fact represent the Benjamins, Marthas and Lonesome Georges of their kind, then marine biodiversity is in more trouble than we thought.