Selection of species for Terminal Terra

To highlight the dynamics over time of species' origins and extinctions, the names figuring in Terminal Terra represent different categories of species. Some 20% are species that became extinct long ago, in prehistorical time, and are only known as fossils. Another 30% of the species on display became extinct in historical times, most of them even in the past hundred years. This emphasizes the recent acceleration in extinction rates as a result of human intervention. The threat of impeding extinction is also evident from the 20% of species that are taken from the IUCN Red List of endangered species. Furthermore, about 25% is formed by a variety of extant (i.e. presently existing) species that are currently not threatened. And finally, the fact that formation of new species still continues is illustrated by the 5% of included species for which there is evidence that they originated in the past million years.

The latter three categories of extant species also include a number of very recently discovered plants and animals, to remind us that our knowledge of living organisms is still far from complete. To date, taxonomists have identified approximately 1.8 million species, mostly insects, flowering plants and vertebrates [3]. But current estimates of the number of undiscovered species —primarily fungi, invertebrates and microorganisms—range from 5 to 30 million [4]. Thus many species may go extinct without us even knowing them.

The species presented in Terminal Terra comprise all groups of organisms, with an emphasis on vertebrates and flowering plants. They include icons of fossil organisms (such as Archaeopteryx, Tyrannosaurus, mammoth and neanderthal), more recently extinct species (like dodo, quagga and passenger pigeon) and threatened species (giant panda, orang-utan, coelacanth), as well as species of economical importance (potato, petunia, yeast) or used as research models (Arabidopsis, Caenorhabditis, Drosophila), with Homo sapiens included for anthropocentric reasons. But most of the Latin names on the display will be unfamiliar to the observer, as passing representatives of the Tree of Life.

(See References for the numbered references above)