You will be given a definition of a task first, then some input of the task.
In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

Haeckel promoted and popularised Charles Darwin 's work in Germany and developed the controversial recapitulation theory ( " ontogeny recapitulates phylogeny " ) .
Output:
Haeckel promoted and popularised Charles Darwin 's work in Germany and developed the influential but no longer widely held recapitulation theory ( " ontogeny recapitulates phylogeny " ) claiming that an individual organism 's biological development , or ontogeny , parallels and summarises its species ' evolutionary development , or phylogeny .