"The father-mother family with two children isolated in a city flat is already insufficient." — Konrad Lorenz

When I was about ten, I discovered evolution by reading a book by Wilhelm Boelsche and seeing a picture of Archaeopteryx.

I grew up in the large house and the larger garden of my parents in Altenberg. They were supremely tolerant of my inordinate love for animals.

In the course of evolution, it constantly happens that, independently of each other, two different forms of life take similar, parallel paths in adapting themselves to the same external circumstances.

Practically all animals which move fast in a homogeneous medium have found means of giving their body a streamlined shape, thereby reducing friction to a minimum.