Agency and space in Darwin's concept of variation

In Kwa's discussion of evolutionary time, he positions Darwin's "natural selection" as heir to an 18th Century mechanicist understanding of nature's history, even when taking to account the important innovations that he brought to it. The key to a modern historical understanding of nature was the concept of variation. Variation was predicated on an understanding of the active role of organisms vis-a-vis their environment. When we place evolutionary theory in the larger framework of the new historical understanding of the 19th century, different conceptualizations of time and space come into focus. Time would become the relational sequence between events, rather than the neutral background on which timeless laws of nature unfold. Space became the theatre on which organisms act out the advantages which variations in their biological constitution had given them.