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The value of arthropod survey, inventory and monitoring projects depends on accurate identification of the taxa under study. While the impact of misidentifications in biodiversity projects is less obvious and immediate than the impact of misidentifications of pests, parasitoids or medically important arthropods, accurate identifications are at the heart of most biodiversity work and are crucial to conservation biology. Furthermore, correct names are predictive, they open the door to the literature on the taxa involved, and allow the data from a study to be properly shared and archived.

Identifying organisms usually demands effort, resources and expertise, and is therefore associated with a cost, but those costs are almost infinitely variable, ranging from essentially free (easily recognized species such as lady beetles) through to thousands of dollars (potentially invasive species in difficult taxa for which there are no keys). Identification costs between these extremes will vary according to the experience of the identifier, the nature of the taxon, and the availability of reference collections, revisions, reviews, monographs and regional works. For these reasons, the pre-set fees for identification implemented by various institutions are impractical and cannot possibly be based on a real per-specimen cost estimate. There is no point in trying to generate generalized figures for the "real cost of insect identification" based on the effort required to identify individual specimens, since in the ideal world any insect should be as readily identifiable as lady beetles and butterflies are today. Identification costs would be uniformly low if, for example, there was a central web site with links to user-friendly, richly illustrated, authoritative, regional keys for all adequately known insects. Instead of asking what it should cost to have individual insect species identified again and again, we should be addressing the costs of developing the tools needed to make those individual identifications simple and accurate.

Meeting the societal cost of insect identifications
Canadians need the capability to identify all of our species, most of which are insects, for a number of good reasons over and above our legal commitments to do so because of the Biodiversity Convention, new federal Species at Risk Legislation, and related laws at national, provincial and regional levels. We need to recognize pests and beneficials, invasive and threatened species, species of interest to related disciplines such as ecology, bioindicator species, species of potential pharmaceutical value, etc. Most insect species are currently difficult, and therefore costly, to reliably identify except by specialists with access to good reference collections. Repeated expenditures to identify species that require specialized expertise and specialized facilities or literature therefore represents an ongoing and significant cost to our society, legitimately met in part by the tax dollars that subsidize the museums and associated systematists who handle these identifications. This, however, is an inefficient approach to meeting the need for identifications and one that could be compared to "giving a man a fish" in the ancient aphorism "give a man a fish and you feed him for a day, teach him to fish and you feed him for a lifetime". What we need to do is to provide our population of naturalists, ecologists, conservation biologists, and others with the necessary tools to do as many of their own identifications as possible.

The tools required, and therefore the products that the taxonomic community must be adequately supported to develop, are as follows:

1) Primary revisions. Basic revisions are the building blocks upon which all further efforts (indeed, all of biology) stands. There is no point in talking about identifications of a taxon in which significant numbers of species have not yet even been described. Good revisions have always included identification tools, although keys in primary revisions are often difficult or impossible for non-specialists to use.

2) Reviews, handbooks and regional monographs. Usually built upon a framework provided by primary revisions, secondary treatments of major taxa such as the highly acclaimed Insects and Arachnids of Canada series go a long way towards making significant groups of insects readily identifiable. Most still require significant expertise and experience, and most (but not all) are difficult to use reliably without a reference collection.

3) User-friendly identification guides. Once fundamental revisions and regional reviews have been developed for a taxon, the next logical step is to use that foundation to develop easily used identification guides. Here in Ontario, any naturalist with a hand lens can now identify several groups for which there are provincial or northeastern North American field guides (for example: dragonflies, macro-moths, butterflies, lady beetles, tiger beetles, long-horned beetles)

4) New tools for insect identification. Newly available software, hardware and other technology is providing unprecedented opportunities for new approaches to insect identification such as computer (matrix) keys and automated identification systems. Implementation of these approaches may allow us to bypass step 3 above, but step 1 remains essential and step 2 will normally be a prerequisite.

The question of interest, then, is not "how much do identifications cost?" but "how can we expedite the above steps to minimize the societal cost of insect identifications?" Steps 1 and 2 (revisions and reviews) must be recognized as fundamental, as there is no point in discussing efficient ways of facilitating identifications if basic taxonomic data are not available for the taxa in question (description, name, comparison to related species, distribution, dichotomous keys). Assuming, then, that the already scarce resources needed for this fundamental work will not be diverted to implement steps 3 and 4 (development of second generation identification tools), what can be done to minimize the societal cost of insect identifications?

New tools for insect identification – magic bullets or massive matrices?
The addition of molecular techniques to the taxonomists’ arsenal has been one of the major (albeit most costly) advances of the last twenty years, and the use of molecular tools for insect identification has already shown great potential to expedite the identification of cryptic species, formerly unidentifiable life stages, and critical taxa such as disease vectors. Recent claims that molecular approaches comprise the only solution to the taxonomic crisis, however, should be taken with a grain of salt. Similar claims have been made by champions of emerging technologies (quantitative phenetics, cuticular hydrocarbons, gel electrophoresis, DNA-DNA hybridisation) in the past, in each case generating a flurry of interest (and funding) but never making a significant impact on how organisms are identified. Some molecular biologists are now proposing that DNA sequences really will provide the magic bullet that earlier genetic technologies failed to yield. While I do not wish to be in any way critical of my colleagues’ very interesting and worthwhile research programs in molecular taxonomy, I would like to suggest that some of the claims being made by proponents of these research programs comprise gross hyperbole and, although they may increase the flow of funding into their research programs, they are not in the best interest of taxonomy as a whole. For example, a recent paper by Hebert et. al. (2002) argues that "the sole prospect for a sustainable identification capability lies in the construction of systems that employ DNA sequences as taxon ‘barcodes’". The authors base their case for this exclusive approach on the claim that "taxonomic expertise is collapsing", combined with the rather peculiar argument that a reliance on morphological taxonomists means that only professional taxonomists will be able to identify things, whereas molecular identifications will free us from that dependence. Their claim that "since few taxonomists can critically identify more than 0.01% of the estimated 10–15 million species, a community of 15000 taxonomists will be required, in perpetuity, to identify life if our reliance on morphological diagnosis is to be sustained" seems to ignore that fact that once a taxon has been revised and reviewed (prerequisites for both molecular and morphological identification) identifications can usually be done by non-specialists. Furthermore, once a taxon is reviewed it is usually not that difficult to develop a user-friendly identification guide (and, as elaborated below, it is now especially practical to do so). We do not need a community of butterfly taxonomists in perpetuity to identify butterflies (although we do need butterfly taxonomists for many other reasons!), nor should we be dependant on taxonomists to identify most other taxa if the right tools are at hand. Hebert et. al. argue that the right tool, a system of DNA barcodes, can be developed for about a billion dollars (presumably American dollars), significantly less than that directed to other megascience projects such as the Human Genome project. While I admire the innovative research program proposed by Hebert et. al. have proposed, it is not the right tool with which to minimize identification costs of Canadian insects.

Having rejected, at least for the moment, a molecular solution to the taxonomic impediment, what are the alternatives? In my opinion, the Canadian entomological community is already moving in the right direction, and has been doing so for a long time through the production of secondary identification products such as checklists and catalogues, manuals, and handbooks. Although progress is slowed by our diminished ranks, opportunities to capitalize on readily available computer hardware and software combined with tremendous advances in digital imaging have set the stage to build on the infrastructure so successfully developed over the last century, and to render the Canadian insect fauna largely identifiable by non-taxonomists. One way this might be expedited is through the widespread use of expert systems or matrix keys developed using software such as LINNEAS, DELTA, 20Q, or LUCID. These programs expedite the construction of non-hierarchical keys that allow the user to select any character and character state from a list (or group of illustrations) rather than being constrained to a sequence of characters as in a traditional dichotomous key. More importantly, matrix keys such as LUCID allow for the almost limitless use of the photographs and other illustrations necessary to make any key user-friendly. In my opinion, the widespread availability of matrix keys on the web will represent the major revolution in insect identification over the next 20 years. This will happen quickly if taxonomists are given adequate credit for the production of matrix keys (ie, if there is a mechanism by which they can be reviewed and recognized as legitimate scientific publications), if funding is available (substantially less than a billion dollars!), and if our diminished taxonomic community is able to continue to generate the revisions and reviews which are necessary prerequisites to the development of morphological or molecular identification tools.

What can be done now to make Canadian insects more identifiable?
Compared to the world insect fauna of millions of insect species, Canada’s total fauna of tens of thousands of species is relatively manageable. Keys already exist to virtually all genera and most species, and Canadian taxonomists are already world leaders in the development of identification tools for all of the major insect orders. Perhaps it is time to launch a unified national effort to produce a guide to the insects of Canada. This could be done either by providing funding and an appropriate venue (a digital journal) for the publication of matrix keys to major groups, or by launching a community-wide effort to develop a more traditional product incorporating photographs of every genus and most species of Canadian insects. The cost of publishing photographs has plummeted in recent years, and new technology for image acquisition makes it easier than ever before to obtain digital images of specimens and characters at any magnification. Many taxonomists have already built up major image libraries, and it is likely that a good proportion of our community of taxonomists would be willing to contribute expertise, time and images as co-authors of the Insects of Canada.

The development of a paper guide to Canadian insects and a concomitant library of images covering every genus in the country would also simultaneously deal with the limiting step in putting together a matrix key for web publication (the assembly of an image library), so these two suggestions are by no means mutually exclusive. Both suggestions require funding, and either could be managed as a flagship project of the Biological Survey of Canada.

¹Recently, the Scientific Committee for the Biological Survey has been discussing the per-specimen costs of insect identification, which prompted me to develop this essay.

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Biological Survey of Canada (Terrestrial Arthropods) home page

Newsletter of the Biological Survey of Canada (Terrestrial Arthropods)

Volume 22 No. 1, Spring 2003

The real costs of insect identification¹

Newsletter of the Biological Survey of Canada (Terrestrial Arthropods)

Volume 22 No. 1, Spring 2003

The real costs of insect identification1

The real costs of insect identification¹