Herbário da Universidade de Coimbra

Herbaria in a time of global change

Since the beginning of agriculture, mankind grew both in number and in the sophistication of demands on biological resources. At present, the changes we have inflicted on the ecosystems acquired such a velocity that they require from us a fast understanding of the consequences of our actions, a full comprehension of the planet we live in, and a radical change in our way of life where required. Necessity and insight will speed up the latter. As for the first two, the biological collections throughout the world, the electronic technologies and the specialists, the taxonomists, are the assets to rely on.

Biodiversity is enormous, but accountable. Roughly 1.75 million species have been described. Insects are, by far, the largest group. Photosynthetic organisms, those that produce vital oxygen and upon which all life depends, are algae and plants, and some kind of bacteria. Known plants total 354.626 species, more or less (e.g. Groombridge, B., Jenkins, M.D., 2002, UNEP-WCMC). 

Biological collections, called herbaria for plants, are physical databases of the variability of biodiversity. More than 250 years of collecting (at least since Linnaeus, 1753) have contributed to a vast worldwide collection of plant specimens kept in good condition in the many global herbaria. The largest herbarium in the world is at Paris (P), with c. 8 million specimens. Herbarium specimens document the incredible diversity of plants and are the foundation of our knowledge of it. Their labels document the identity, habitat, phenology and distribution of species.

Only using large quantities of material is possible to make comparisons and draw scientific conclusions. In these large collections, specimens may even exist that turn out to be new to science! Also, only using material of a wide age span can conclusions be drawn on changes in habitats and whole ecosystems. Old material investigated long ago can reveal new aspects when re-examined in the light of new techniques; nowadays, even DNA can be extracted from it.

Fast communication and information exchange are fundamental to adequately accelerate the investigation on biodiversity. This has never been made so easy with the present-day electronic facilities that both store enormous amounts of information and easily access information in the internet. Biodiversity informatics facilitates the efforts to resolve the intrinsic slowness of the study of biodiversity due to the enormous number of the existing organisms and the fact that they are deposited in so many scattered collections. It does so by creating new efficiencies for data capture and retrieval, and providing novel approaches for interdisciplinary analysis and visualization. This is particularly relevant when it comes to repatriate the large amount of information contained in the most relevant herbaria of the western, once colonizing, countries (CBD 5.1.6.) . To link all information available on each species is the ultimate goal of the Global Biodiversity Information Facility (GBIF) and also to make it ready to use in an interactive way together with all the other information on the geographical area of the species, from climate to soil. This opens a world of scopes that can even involve climate change. Such global sharing of information is possible only when the criteria for database construction meet GBIF requirements on inter-operability.

In the present scenario, the specialists, the taxonomists, are called to produce biological information and decision at faster rates. It takes a long time to train taxonomists because their job is multidisciplinary and on many organisms. In spite of the importance of their work, a combination of factors is leading taxonomists themselves towards extinction in various parts of the world. This problem was recognized as an impediment to conservation and sustainable use of biodiversity by the CBD. In 1988, at a meeting of the Global Taxonomy Initiative, it was signed The Darwin Declaration. This Declaration was on removing this “taxonomic impediment” and to promote capacity building in taxonomy. Since then, Darwin Initiatives addressed to taxonomic expertise and biological collections have multiplied throughout the world (e.g. Kew Repatriation of Herbarium Data for Northeast Brazil).