The process of dying out is as old as life on Earth is. Species come into being, change and die out. The natural extinction of one species goes on for thousands of years. Man, however, speed up this process many times over. They intervene the evolution of species, though they don't know, which consequences that will have. The first piece of circumstantial evidence is the dissappearance of species in wide parts of their spreading area. Examples are to be found in the early Middle Ages, already. For the most part it's simply a question of direct (hunting) or indirect extermination (destruction of the biotop) and not a question of natural dying out. Natural processes like climatical change seldom have a part in it.

In the 20th century more species of animals were extinct in Thuringia than in all centuries before. As 80% of the 400 extinct species are little, inconspicuous invertebrates, it's hardly noticed even today.

The Great Bustard (Otis tarda) was breeding in Thuringia until 1956. This imposing crane prefers open and large fields and meadows. The food mainly consists of seeds and small insects. Great Bustards are very timid. The modern industrialized agriculture with all its side effects like use of biocides, extensive agriculture and the "clearing up of the land" is the main cause for the drastic decline. The wiring of the countryside (electrified routes) demands many victims of this species, because the climsy fliers often have accidents in the high tension lines.

The Rock Sparrow  (Petronia petronia) as a breeding bird was seen in Thuringia in 1931 last. As a Southern European it lives in the open land around the castles and villages along the Muschelkalk-slopes to the north and south of the Thuringian forest. It has its last stable occurence in the "Drei-Gleichen-Area" southwest of Erfurt. The causes of decline are unclarified.

The Insects represent the largest part among the exterminated animals. The time of the disappearance of many species is not registered. Often only a specialist for some groups of insects can tell wether the species is extinct or not.

The destruction of the living spaces is the main cause for the extermination of the vetebrates. But none of this species has been specificly exterminated.