How many species make up the global biodiversity? Is it 3 million or 100 million? The degree of uncertainty is surprising and only a few small groups are really ‘known’. It is a field where the collection and classification of information over past centuries has been a fragmented affair based on varied criteria. Yet over time these efforts have nevertheless produced an impressive body of knowledge that taxonomists worldwide have now decided to classify and enumerate in a coherent manner. RTD info looks at the compilation of the Catalogue of Life, a genuine directory of the biosphere with a Europe section managed by the Species 2000 Europa project, financed by the European Union.
Listing and classifying life itself is to attempt to bring order to its chaotic profusion. Commenced by Linneus in the 18th century and attempted by Aristotle much earlier, for a long time it seemed an impossible task. Even today, we are still a long way from achieving the goal. To date, we have named and, to a degree, described about 1.7 million species. But the question is, 1.7 million out of how many? We still have no idea. Perhaps between 5 and 10 million, although some estimates are as high as 100 million. Surprising as it may seem, the degree of uncertainty (from 1 to 60) regarding the number of living species on Earth is far greater today than the uncertainty about the number of stars in the galaxy. Only a few small groups have been described relatively extensively: the vertebrates, vascular plants, corals, and butterflies, for example. Together, these represent no more than 5% of existing species.
The ‘genome’ of the biosphere The famous biologist Edward Wilson, Professor at Harvard University, made an appeal back in 2000 for man to make a major effort to put an end to his ignorance of the life around him. In an editorial in the magazine Science, he called for "a concentrated effort, comparable to that of the human genome project (HGP), to make a global inventory of biodiversity, from pole to pole and from whales to bacteria, within a relatively short period”. Wilson estimated the cost of the task at 500 dollars per species, making about 5 billion dollars in all over ten to 20 years. This is not much more than the cost of the human genome project and, to his thinking, would be just as useful to the health of the planet as the HGP was for man.
If this almost Herculean task seems less unrealistic today, it is mainly because of the new means made available by the growth of computers and the internet over the past 20 years. As Frank Bisby, of Reading University (UK), Coordinator of the Species 2000 Europa project, explains: “There is a parallel between the needs of the science of biodiversity and the opportunities offered by globalisation and the interoperability the internet permits.”
According to this British researcher, the parallels are evident at three levels: first, in terms of the global dispersion of biodiversity experts. Secondly, in their interdependency, as “those who set conservation priorities need information from neighbouring regions or climatically similar regions located on distant continents”. And finally, because the science of biodiversity involves continually switching the focus from field observations at the most local level to very general concepts such as ecosystems, biomasses(1), flora, fauna, the impact of invasive species, etc. "As a result, a central objective of the computerisation of biodiversity is to develop systems that permit the interoperability and synthesising of knowledge through extensive sets of local systems, so as to include them in a global architecture of knowledge,” states Frank Bisby.
Directory of life This is essentially what is involved in compiling the Catalogue of Life (CoL), an ambitious international project of which Species 2000 Europe is the European component. This pooling and classifying of existing knowledge is an essential stage in improving our knowledge of the living world as, at present, the information is extremely dispersed. Although admittedly we have come a long way from the time of monographs devoted to each species – with Indian ink drawings of physiological particularities, in the case of invertebrates made with the aid of a magnifying glass or microscope, and also associated with a reference specimen carefully stored away in a jar or drawer in a national museum.
Most information is now available in electronic form and some museums have already digitised many photographs of their exhibits. Major progress has therefore been made – even if electronic information is far from being the rule – but, at the same time, these new technologies have permitted a profusion of databases founded on different criteria (local species, groups of species, etc.), resulting in an unfortunate dispersion of information.
The Species 2000 researchers believe that there are as many as 150 global – thus non-regional – databases, each containing details of between 10 000 and 25 000 species that must be networked to bring together all the species defined. For Europe alone, scientists working on the Europe section had the task of pooling the knowledge stored in 24 global databases. “The work proved much more complicated than we had envisaged,” admits Pamela Harling of Reading University, one of the programme managers. “The databases were very heterogeneous and were the result of very different approaches.” Despite this, the programme has been successful with 18 databases already incorporated on the Species 2000 website and the rest due for inclusion by the time the project expires at the beginning of 2006. The next step will be to include more local databases to have a truly satisfactory coverage for Europe.
The product of all these efforts, the Catalogue of Life is a genuine directory of life. It is presented in the form of a dynamic list, available on the internet in real time and updated once a year by a CD-ROM that is distributed free of charge. You simply enter the Latin name of a species to obtain, with just a few clicks, a series of pieces of information which, in the past, would have taken months to collect and with a very high risk of error. Eight key elements are provided for each entry: current scientific name, synonyms, common names, family and classification, reference database, geographical distribution (when available), and scientific references corresponding to the data provided.
Misumena’s doubles The fundamental reason for this painstaking work is to put an end to the many problems posed by species identification and nomenclature. Flushing out the synonyms is a particular headache for taxonomists. One such example is the spider Misumena vatia, also known as the crab spider, which is very common in Western Europe where it often lurks waiting for its prey at the centre of flowers, and depending on its mimetic abilities for concealment. Like many other species of varying size and colour with a very wide distribution range, Misumena vatia has been given a great many different scientific names, each author believing he was dealing with a species not previously described. The great Linneus himself, who was no doubt confronted with two very different specimens, named it Aranea calycina in 1758 and Aranea 4-lineata in 1761. Clerck, who was the first to describe Misumena vatia in 1757, also fell into the trap when he described Araneus vatius a few years later, when it was in fact the same spider. Over the decades and the centuries, this same species has been given about 30 different names (Aranea citrina, Aranea sulphurina, Misumena citrea, Thomisus pratensis, etc.). The experts finally detected these synonyms when examining the descriptions and reference specimens conserved in collections. But it is still not unusual for a taxonomist to name a ‘new’ species that already has a name elsewhere in the world.
Thanks to the Catalogue of Life, the end to the problem is now in sight, as this offers a unified and validated list. On entering Misumena vatia, a complete list of all the synonyms is displayed as well as the sites to visit to obtain further information on the species. “This will be a very valuable tool for all those who have to name species,” explains Pamela Harling. “Not just people involved in conservation, but also international control bodies (involved in combating the trade in species, for example) or agricultural organisations such as the FAO or the European Environment Agency."
Thus, if researchers want to know the impact of more intensive farming practices on a region whose insect population was studied in detail a few decades ago, they can make a census of present populations and then compare them with those of the past. A tool such as the Catalogue of Life will make it possible to improve the quality of analysis and avoid any confusion.
Objective 2011 In March 2005, scientists celebrated the entry of the 500 000th species to the Catalogue of Life. They hope to reach the 800 000 mark by 2006, which means they will have listed half of all known species. After that, the task will become more difficult as it will require increasing recourse to regional databases that pose more complicated problems of synonyms and heterogeneity of data. The aim remains to catalogue all described species by 2011, thus providing a solid central body of knowledge around which every year scientists will be able to organise the new knowledge they never fail to discover.
Classification is an ongoing exercise as new discoveries are made revealing unsuspected links, in particular due to progress in genetics. Every year, researchers describe thousands of new insects, about 2 000 unknown flowers, between ten and 20 species of bird previously unknown to ornithologists, and countless worms, algae, bacteria and viruses. In short, this is an impressive flow of new information that must be incorporated in the database. This is why updating and maintenance is a vital aspect of a project of this kind – as indeed it always has been for collection specimens.
Yet this influx of new knowledge remains very insufficient when compared with the scale of life. At the present rate, it will take several centuries to describe even a significant portion of it. “There are at present fewer than 10 000 taxonomists in the world, and they are particularly absent where they are most needed, namely in the tropical countries – even if Brazil is a fortunate exception,” points out Pamela Harling. To make matters worse, there are some areas of life – centipedes, for example – with which only a handful of specialists are familiar, and they are coming up to retirement age. But despite these problems, the fact remains that the Catalogue of Life is an excellent new tool and one that will prove increasingly valuable to all those who are trying to understand our fragile biodiversity and to protect it for future generations.
(1) There are two principal types of biomass, terrestrial and aquatic. They represent biotic regions characterised by a distinctive set of ecosystems.
A profusion of bases…
The Catalogue of Life brings together the most diverse data on life, as obtained from the Bacteriology Insight Orienting System (BIOS), the International Legume Database and Information System (ILDIS), the Australian Faunal Directory, and specialised databases on cephalopods (Cephbase), anemones (Hexacorallians ...
The Biota cluster
The European Union finances many programmes on biodiversity, via the Biodiversity Project Cluster (Biota), which includes dozens of sometimes very large-scale projects. Their common objective is to try and resolve conflicts between biodiversity, society and the economy, define tools and indicators to ...
The Catalogue of Life brings together the most diverse data on life, as obtained from the Bacteriology Insight Orienting System (BIOS), the International Legume Database and Information System (ILDIS), the Australian Faunal Directory, and specialised databases on cephalopods (Cephbase), anemones (Hexacorallians of the World), viruses (The Universal Virus Database) or spiders (The World Spider Catalogue).
Species 2000 Europa draws on European databases, such as Fishbase (30 000 entries) and Algaebase (38 000 entries), Titan which is concerned with wood beetles (15 000 entries) and Species fungorum, which lists several thousand mushroom varieties.
The Biota cluster
The European Union finances many programmes on biodiversity, via the Biodiversity Project Cluster (Biota), which includes dozens of sometimes very large-scale projects. Their common objective is to try and resolve conflicts between biodiversity, society and the economy, define tools and indicators to measure trends in biodiversity, and catalogue (through databases) the elements of which it is composed. Examples are the recent environmental project Alarm, which is interested in the effects of various elements (climate change, toxic agents, decline of pollinators, etc.) on the environment, Bio Hab, which is trying to improve knowledge of natural habitats, Metabird, focused on birds, and Plant Dispersal, which is studying the effects on plants of the fragmentation of habitats.