Given the question: Given the following passage  "By the mid-1870s, most scientists accepted evolution, but relegated natural selection to a minor role as they believed evolution was purposeful and progressive. The range of evolutionary theories during "the eclipse of Darwinism" included forms of "saltationism" in which new species were thought to arise through "jumps" rather than gradual adaptation, forms of orthogenesis claiming that species had an inherent tendency to change in a particular direction, and forms of neo-Lamarckism in which inheritance of acquired characteristics led to progress. The minority view of August Weismann, that natural selection was the only mechanism, was called neo-Darwinism. It was thought that the rediscovery of Mendelian inheritance invalidated Darwin's views.",  answer the following question. Note that the answer is present within the text.  Question: What made people believe less in Darwinistic views on evolution?
The answer is:
inheritance