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1.1. Biodiversity

Life has been evolving in the last 3,5 billion years. Along the way thousands of different organisms
developed, some of them disappeared along the way (like the dinosaurs for example), but the
result is that today estimates point out that, currently, there are 8,7 Million species on earth.

In order to understand life diversity, scientists have categorized life forms in groups, accordingly
to their characteristics and evolution.

Since natural sciences aroused, it was somehow evident that was both important and useful to
measure life diversity. Therefore, Taxonomy, in Biology, arose as an important discipline that
encompasses the description, identification, nomenclature, and classification of organisms. This
life classification is permanently being updated accordingly to new findings.

Image 2. Currently major life forms are grouped in 6 Kingdoms: Animalia, Plantae, Fungi, Protista,
Eubacteria, Archaebacteria.

Despite Taxonomy being able to provide an organization within life diversity, during the 80’s
Biodiversity concept gained strength, providing a way to measure the diversity variability of life on
Earth. Biodiversity concept established a connection between space, time and species diversity
and representativity. It is a multi-level concept depending on the subject that we are addressing:
Intra-species diversity: diversity between individuals or populations of a certain species. Having
the human population as an example it is easily understandable that phenotypic characteristics,
for example height diversity, eye colour within humans are an outcome of its genetic diversity.

Certain location / area / ecosystem diversity: diversity of species or habitats and their
representativity within a particular geographical area. For example, to evaluate the biodiversity of
a country it is important not only to list species, but also their abundance and their interaction
diversity, in space and time, between each other and with abiotic factors, which constitutes a
diversity of habitats and ecosystems.

This project has been funded with support from the European Commission. This communication reflects the
views only of the author, and the Commission cannot be held responsible for any use which may be made of the

information contained therein.