[Lamarck needs Darwin: the search for purpose in the study of evolution and of history].

Lamarck's theory of the inheritance of acquired characteristics and immediate responses to environmental challenges has offered a promise of protagonism of human beings and their fellow travellers, the other organisms, in the evolutionary process. Darwin's theory about evolution by natural selection does not offer this consolation and does not presuppose anything else other than gradual changes in the composition of natural populations. The study of ecology, ethology, neurobiology, animal culture, psychology and human history reveals that the lamarckian interpretations of change and character transmission processes always assume what they intend to explain, that is previous processes of darwinian evolution that guarantee the adaptive nature of the observed responses. The permanent search of direction and intentionality in evolutionary processes by many scientists suggests the limited acceptance of materialistic explanations as those offered by Darwin's theory.