Charles Darwin
Charles Darwin argues that all life is connected through descent with modification, shaped over long periods by natural selection.
Competition for limited resources means that organisms possessing advantageous variations are more likely to survive and reproduce, gradually shaping new species over time.
Faced with a fragmented and incomplete geological fossil record, Darwin relied heavily on biogeography alongside other lines of evidence to support evolutionary descent.
Evolution operates as a branching process where diverse species diverge from common ancestors rather than progressing in a linear, purposeful ladder toward biological perfection.