Wednesday, 15 February 2017

Backyard bonanza: collating stats for a predator-free future

I've previously discussed how a lack of understanding of statistics can cause consumers to make poor choices, so it would seem that increasing the public's understanding of them can only be a good thing. Therefore, along the lines of New Zealand's annual garden bird survey, I decided to do a bit of citizen science. My aim was to record the highest number of each fauna species seen at one time, either actually in my garden or seen from my garden. The time frame was a calendar year, so as to take into account seasonal migrations and food availability. As an aside, it might have been easier to count flora (after all, it doesn't move very fast) but with Auckland being the weediest city in the world and my floral knowledge much weaker than my recognition of fauna, I opted for the easier option of any animal that I could see without using a microscope.

A meta-analysis released this month states that almost twenty-five percent of birds on the IUCN Red List of Threatened Species are being affected by climate change. In addition, with last years' announcement to make New Zealand predator-free by 2050, such surveys might be useful for locating concentrations of introduced pest species. In a way, I'm providing a guide that anyone can follow with the minimum of effort (hint, hint). So here are my results, followed by some more information:

Class/species Native/self-introduced Number seen
Ant (unknown species) Yes Numerous
Asian paper wasp No 3
Black field cricket Yes 4
Bumble bee No 1
Bush cockroach Yes 14
Cabbage tree moth Yes 7
Cabbage white butterfly No 2
Cicada Yes 2
Click beetle Yes 2
Common bag moth Yes 1
Crane fly Yes 1
European earwig No 1
Ground beetle Yes 2
Honey bee No 1
Housefly No 7
Ladybird Yes 2
Monarch butterfly Yes 17
Shield bug Yes 3
South African praying mantis No 22
Tree weta Yes 18
Bird dropping spider Yes 1
Black cobweb spider Yes 1
Black house spider Yes 1
Daddy long-legs Yes 3
Jumping spider Yes 1
Nurseryweb spider Yes 1
Slater spider Yes 1
White tail spider No 1
Earthworm No 5
Tiger worm No Numerous
Springtail No Numerous
Centipede Yes 3
Common garden snail No 9
Rainbow skink No 2
Australasian hawk Yes 1
Blackbird No 2
Black headed gull Yes 3
Eastern rosella No 4
Fantail Yes 2
Goldfinch No 3
Greenfinch No 2
House sparrow No 14
Myna bird No 4
Rock pigeon No 5
Silvereye Yes 7
Song thrush No 1
Spotted dove No 1
Starling No 4
Tui Yes 1
Cat No 2
Chicken No 1
Dog No 1
Hedgehog No 1
Mouse No 1
Rabbit No 1

The first thing that seems obvious is just how many non-native species I observed, some deliberate introductions whilst others accidentally brought to New Zealand, but all within the past two centuries.

Now for some interesting comments about how statistics can be (mis)interpreted:

1) The method I chose to order the table by could affect how easy it is to find key points of interest. Alphabetical order is familiar but is simply a well-known form of cataloging. Therefore it can be seen as a neutral form of presentation, not emphasising any particular pattern of the results. Had I ordered by native/non-native, it might have become more apparent how many of the latter bird species there are. If I had ordered all species in one list by this method, rather than in separate classes, the pattern would have been obscured again. So simply by selecting a certain order, results can appear to support a certain notion.

2) How useful is this data if it lacks supporting information? By this, I mean factors that might affect the count: Is it a common or garden (yes, that's a pun) location or an highly unusual one? Is the locale urban or rural? What are the surroundings? How big is the garden and how much vegetation is there? Is the vegetation primarily native or non-native? I could go on like for this ages, but clearly to get a more sophisticated understanding of the causes behind the figures, this information is necessary. Even then, two locations that are almost identical to a casual observer might appear profoundly different from the vantage point of say, earthworms. I will admit to (a) having built 2 weta motels and a bug motel; and (b) feeding silvereyes in winter; and (c) having made a tui sugar water feeder that has been totally ignored. Go figure!

3) Are there any other obvious factors that could affect wildlife? How managed is the location? Are chemicals such as weedkiller used or is the garden solely organic? Again, this can have a massive effect on wildlife, such as pesticides that remove insects at the base of food webs. On the one hand, if mine is an organic garden surrounding by neighbours who spray their foliage, then it could be an island of suitability in a comparatively barren terrain. But alternatively, if most of the neighbourhood isn't fauna-friendly, how likely would my garden get visited even on the off-chance by animals that can't live in the wider area?

4) Of course there's also contingency within natural selection. For example, quite by chance some species can survive on foods not native to their ecosystem. Although stick insect numbers in New Zealand were drastically reduced thanks to DDT, gardens don't need to contain their native food plants in order to support them. In the south-west of England, three species of accidentally-introduced New Zealand stick insect have flourished for decades on the likes of roses! Also, unusual events can affect populations: in this case, the two rainbow skinks appeared several months' after laying some ready lawn so I can only assume their eggs arrived with the turf, the previous five years having seen no skinks whatsoever.

5) When it comes to surveys, timing is also important. As you might expect, most of my observations took place during the day, with the only nocturnal ventures being on clear nights when using my telescope. The moths and hedgehogs were mostly seen at night, whilst had I included birds I could hear as well as see, then a morepork would have been added to the list. Again a simple prejudice, in this case sight over sound, has skewed the statistics. The large number of mantises were not adults but nymphs all hatching from a single ootheca. As for the monarch butterflies, they were a combination of caterpillars, chrysalis and adults, having appeared in much greater numbers this year than previous, despite no additional swan plants (their only food). Interesting, a clump of twenty or so mature swan plants a few streets away hasn't yielded any monarchs in any of the three stages. Presumably, predators such as wasps are responsible.

The sheer randomness of nature is exciting, but doesn't exactly help to uncover why populations are such as they are found via small-scale studies. Oh, and further to the damage invasive species have wrought on native wildlife, you may be interested to learn that none of the mammals belonged to me, the cats and dog being owned by friends and neighbours whilst the rabbit was an escapee from a dozen houses away!

6) Finally, there's the scale prejudice. Although I have a basic microscope, I didn't include such tiny wonders as tardigrades and bdelloid rotifers, even though garden moss and leaf litter respectively has revealed these wee critters. My page of nature photographs shows this prejudice, with microscopic fauna getting their own page.

So, what can we learn from this, apart from the large number of non-native species commonly found in Auckland? Perhaps that raw data can be presented in ways to obscure patterns or suggest others, should the publisher have an agenda. Furthermore, without access to highly detailed meta data, the statistics by themselves tell only a small part of the story and as such are open to wide-ranging interpretation by the reader. Therefore the next time you read about some percentage or other, remember that even without manipulation or omission, survey data is not necessarily pure, unsullied and free of bias.

Monday, 30 January 2017

Hold the back page: 5 reasons science journalism can be bad for science

Although there's an extremely mixed quality to television science documentaries these days (with the Discovery Channel firmly at the nadir) - and in stark contrast to the excellent range of international radio programmes available - the popular press bombards us daily with news articles discussing science and technology. Both traditional print and online publications reach an enormous percentage of the public who would never otherwise read stories connected to STEM (Science, Technology, Engineering and Mathematics). Therefore these delivery channels and the journalists who write material for them face an immense challenge: how to make science accessible and comprehensible as well as interesting. How well they are doing can be judged by the general public's attitude towards the subject...which is currently not that great.

In November 2016 Oxford Dictionaries stated that their Word of the Year was 'post-truth', which refers to 'circumstances in which objective facts are less influential...than appeals to emotion and personal belief.' Clearly, this is the antithesis of how good science should proceed. Combined with the enormous output from social media, which gives the impression that anyone's opinion is as valid as a trained professionals and you can see why things aren't going well for critical thought in general. Did you know that a Google search for 'flat earth' generates over 12 million results? What a waste of everyone's time and data storage! As they said about Brexit: pride and prejudice has overcome sense and sensibility. Here then are five reasons why popular science journalism, mostly covering general news publications but occasionally dipping into specialist magazines too, can be detrimental to the public's attitude towards science.

1) Most science writers on daily newspapers or non-specialist periodicals don't have any formal science training. Evolutionary biologist Stephen Jay Gould once pointed out that journalists have a tendency to read summaries rather than full reports or scientific papers, thus distancing themselves from the original material before they even write about it. The problem is that an approach that works for the humanities may not be suitable for science stories. We're not critiquing movies or gourmet cuisine, folks!

As an humorous example of where a lack of research has led to a prevalent error,  a 1984 April Fools' Day spoof research paper by American journalism student Diana ben-Aaron was published in 350 newspapers before the original publisher admitted that Retrobreeding the Woolly Mammoth was phoney. One of the facts that ben-Aaron made up (and still remains unknown) is that woolly mammoth had fifty-eight chromosomes. This number is now ubiquitous across the World Wide Web from Wikipedia to the Washington Post, although I'm pleased to see that the National Geographic magazine website correctly states the situation. Clearly, anyone who follows the President Trump approach that "All I know is what's on the Internet" isn't going to get the correct answer.

This isn't to say that even a scientifically-trained journalist would understand stories from all sectors: the pace of advance in some fields is so fast than no-one can afford the time to maintain a sophisticated understanding of areas beyond their own specialism. But it isn't just particular research that is a concern: general concepts and methodology can be ignored or misunderstood; whilst a lack of mathematical training can easily restrict an understanding of how statistics work, with error bars and levels of significance often overlooked or misrepresented.

Related to this ambiguity and margin for error, journalists love to give definitive explanations, which is where there can be serious issues. Science is a way of finding ever more accurate explanations for the universe, not a collection of unchangeable laws (excepting the Second Law of Thermodynamics, of course). Therefore today's breakthrough may be reversed by tomorrow's report of sample contamination, unrepeatable results or other failure. It's rarely mentioned that scientists are willing to live with uncertainty - it's a key component of the scientific enterprise, after all. Yet in the event of an about turn or setback it's usually the scientists involved who get blamed, with accusations ranging from wasting public money to taking funding from something more worthwhile. Meanwhile, the journalist who wrote the original distorted account rarely gets held responsible. As for the one-sided scare stories such as nicknaming GM crops as 'Frankenfoods', this lowers what should be a serious public debate to an infantile level extremely difficult to overthrow.

2) How many science documentaries have you seen where the narrator says something along the lines of “and then the scientists found something that stunned them”? Such is the nature of story-making today, where audiences are deemed to have such short attention spans that every five minutes they require either a summary of the last ten minutes or a shock announcement. This week I saw a chart about bias within major news organisations: both CNN and USA Today were labelled as 'sensational or clickbait'. I've repeatedly read about scientists who were prompted by journalists towards making a controversial or sensational quote, which if published would distort their work but provide a juicy headline. It seems that limiting hyperbole is a critical skill for any scientist being interviewed.

Journalists don't owe invertebrate paleontologists, for example, a free lunch but there is a lot of good professional and occasionally amateur science being conducted away from the spotlight. Concentrating on the more controversial areas of research does little to improve science in the public's eye. Even reporting of such abstract (but mega-budget) experiments as the Large Hadron Collider seems to be based around headlines about 'The God Particle' (nearly six million results on Google) A.K.A. Higgs Boson (less than two million results). Next thing, they'll be nicknaming the LHC ‘The Hammer of Thor' or something equally cretinous. Although come to think of it…

The World Wide Web is far worse than printed news, with shock headlines ('It Was The Most XXX Ever Found - "It Blew My Mind," Expert Says') and over-inflated summaries that would make even lowbrow tabloids blush. Even specialist periodicals are not immune to the syndrome, with New Scientist magazine being particularly at fault. In 2009 it published the silly headline 'Darwin was wrong' which drew the ire of many biologists whilst providing a new form of ammunition for creationists. In 2012 their special 'The God Issue' turned out to contain less than fifteen pages on religion - but then it is meant to be a popular science periodical! In this vein the Ig Nobels seem to get more attention than the Nobel Prizes as journalists look for a quirky man-bites-dog angle to convince the public that a science story is worth reading.

3) Talking of which, journalists want to reach the widest possible audience and therefore looking for human angle is a prominent way to lure in readers. The two most recent Brian Cox television documentary series, Human Universe and Forces of Nature have concentrated on stories around families and children, with the science elements being interwoven almost effortlessly into the narrative.

In print and digital formats this bias means that the focus is frequently on articles that might directly affect humanity, especially medical, agricultural and environmental stories. This puts an unbalanced emphasis on certain areas of science and technology, leaving other specialisations largely unreported. This might not appear bad in itself, but lack of visibility can cause difficulties when it comes to maintaining public funding or attracting private philanthropy for less commercial and/or more theoretical science projects.

Another method used to make science more palatable is to concentrate on individual geniuses rather than team efforts. I assume only a very small proportion of the public know that theoretical physicists do their best work before they are thirty years old, yet the seventy-five year old Stephen Hawking (whose name is now a trademark, no less) is quoted almost every week as if he were Moses. He's well worth listening to but even so, Professor Hawking seems have become a spokesperson for almost any aspect of science the media want a quote on.

4) With competition tougher than ever thanks to social media and smartphone photography, journalists face ever tighter deadlines to publish before anyone else. This can obviously lead to a drop in accuracy, with even basic fact-checking sometimes lacking. For example, a year or two ago I sent a tweet to the British paleopathologist and presenter Dr Alice Roberts that the BBC Science and Environment News web page stated humans were descended from chimpanzees! She must have contacted them fairly rapidly as the content was corrected soon after, but if even the BBC can make such basic blunders, what hope is there for less reputable news-gathering sources? As with much of contemporary business, the mentality seems to be to get something into market as quick as possible and if it happens to be a smartphone that frequently catches fire, we'll deal with that one later. The Samsung Galaxy Note 7's recent debacle is the gadget equivalent of the BBC error: beating the opposition takes precedence over exactitude.

It's one to thing to define science as striving towards more accurate descriptions of aspects of reality rather than being a series of set-in-stone commandments, but publishing incorrect details for basic, well-established facts can only generate mistrust of journalists by both scientific professionals and members of the public who discover the mistake. Surely there's time for a little cross-checking with reference books and/or websites in order to prevent the majority of these howlers? Having said that, I find it scary that a major media organisation can commit such blunders. I wonder what the outcry would be if the BBC's Entertainment and Arts News page claimed that Jane Austen wrote Hamlet?

5) Finally, there's another explanation that has less to do with the science journalists themselves and more with what constitutes newsworthy stories. Negativity is the key here, and as such science news is swept along with it. For example, the BBC Science and Environment News web page currently has three articles on climate change and animal extinctions, an expensive project technology failure, earthquake news and a pharmaceutical story. Like a lot of political reports, those concerning STEM subjects concentrate on the bad side of the fence. Unfortunately, the dog-bites-man ordinariness of, for example ‘Project X succeeds in finding something interesting' usually precludes it from being deemed media-worthy. The ethos seems to be either find a unique angle or publish something pessimistic.

One tried and tested method to capture attention is to concentrate on scandal and error: science is just as full of problems as any other aspect of humanity. Of course it is good to examine the failure of high-tech agriculture that led to the UK's BSE 'mad cow' disease outbreaks in the 1980s and 90s, but the widespread dissemination of the supposed link between MMR and autism has caused immense damage around the world, thanks to a single report being unthinkingly conveyed as rock-hard evidence.

Bearing in mind that journalism is meant to turn a profit, perhaps we shouldn't be surprised at how misrepresented scientific research can be. It's difficult enough to find the most objective versions of reality, considering all the cognitive bias in these post-truth times. There are no obvious answers as to how to resolve the issue of poor quality science reporting without either delaying publishing and/or employing scientifically-trained staff. The market forces that drive journalism unfortunately mean that STEM stories rarely do science justice and often promote a negative attitude among the rest of mankind. Which is hardly what we need right now!