FIGURE 2 in The Encyclopedia of Life vs. the Brochure of Life: Exploring the relationships between the extinction of species and the inventory of life on Earth

FIGURE 2. Relationships between the rate of description of new species ('Discovery', left axis; current values, 1 = 10,000 species/ year; logarithmic scale), the time needed to describe all the species at that rate ('Time', right axis; in years; logarithmic scale), and the number of species that are lost to extinction during this time ('Biodiversity loss', horizontal axis; logarithmic scale). Three estimates of the total number of species living in year 2000 are considered: a very low estimate, 3 million (thin curves); a middle estimate, 10 million (dotted curves), and a high estimate, 100 million (thick curves). For each case, two curves are shown: discovery rates (D curves, like, D3 for 3 million species or D100 for 100 million) and time to complete the Encyclopedia of Life (i.e., time to extinction of the species indicated in the horizontal axis; t curves, like t10 for 10 million). Vertical and horizontal dotted lines are used in the figure as an example and evidence that, if the total number of species existing in year 2000 is estimated in 10 million (dotted curves), ca. 106 species (point a) will be lost during the completion of the Encyclopedia (in a time span above 100 years, point b) if we work at a rate of discovery close to 7 times the current one (point c).