A "Taxonomist" ist someone who ...

1) describes species
2) revises taxa
3) works code compliant
4) has an academic education in taxonomy
5) has comprehensive knowledge of a taxon
6) can identify a group of organisms
7) is paid for taxonomic work
8) is member of a systematic society

These are only a few possible criterias. Not all of them apply to all circumstances. There are amateur-taxonomists who make valuable contributions to taxonomic work and unfortunately not all educated taxonomists are being paid for their work.

Why does the world need taxonomy?

Taxonomy is the area of biological research that deals with the naming (nomenclature), identification and classification of organisms. For the task of systematically organizing nature taxonomists use morphological traits (e.g. anatomy, flower composition). They also employ methods of chemistry, biochemistry and genetics in order to clarify relations between different organisms. Depending on area of expertise taxonomists conduct their work in natural collections, museums, botanical gardens, industries (e.g. pharmaceutical industry), universities and other research institutions. Although results of taxonomic research often remain “invisible” they constitute the foundation for many research endeavours in the field of life science.

One area where taxonomy matters and affects us most directly is the choice of appropriate sources of food. How else would we know which plants are edible or poisonous? (Example: Cinnamon) Furthermore without the recording of nature by taxonomists we would not have access to knowledge necessary to implement nature conservation. We would not be able to identify species that are in need of protection or prioritize geographic regions for conservation. It would be likewise impossible to estimate the magnitude of species loss. Research about the impacts of climate change also needs taxonomy in order to recognize existing patterns in nature. The comparison of old and new taxonomic data in combination with climate data for instance provides clues about the impacts of climate change. The discovery of numerous active pharmaceutical ingredients would have been impossible without taxonomic research (Examples: Umckaloabo®, Calanolide A, Teatree oil). There are 50.000 plant species used worldwide for medical purpose alone. By identifying plant species and studying their genetic make-up taxonomists make significant contributions to pharmaceutical research. Biological control of pests in agriculture and conservation is another field where taxonomy plays an important role (Example: Gumtree, St Helena). The same can be said in regards to the monitoring and control of invasive species which has increasingly become a challenge worldwide (Example: Ladybird, Germany).

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