March 18 (UPI) -- An evolution theory espoused 161 years ago by naturalist Charles Darwin has finally been proven, University of Cambridge researchers reported on Wednesday.
Research led by Laura van Holstein, of the Cambridge biological anthropology department, confirmed that mammal subspecies are more crucial in evolution that previously thought.
The study, published Wednesday in the journal Proceedings of the Royal Society B, says the research can be used to predict which species are most likely to become endangered or extinct.
The study builds on Darwin's work explained in his 1859 book "On the Origin of Species," in which he hypothesized natural selection, known commonly as "survival of the fittest."
He published the book after visiting the Galapagos Islands to observe the dynamics of its plants and animals, and argued that organisms evolve through natural selection. His observations conflicted with the Bible's account of creation and caused significant controversy.
"Darwin said animal lineages with more species should also contain more varieties," van Holstein said. "Subspecies is the modern definition. My research investigating the relationship between species and the variety of subspecies proves that subspecies play a critical role in long-term evolutionary dynamics and in future evolution of species. And they always have, which is what Darwin suspected when he was defining what a species actually was."
The current research confirmed Darwin's hypothesis using evidence from naturalists working prior to Darwin. It also confirmed that evolutionary changes occur differently in land-based and sea mammals, largely because of differences in their capability to roam freely.
"If a natural barrier like a mountain range gets in the way, it can separate animal groups and send them off on their own evolutionary journeys," she said. "Flying and marine mammals, such as bats and dolphins, have fewer physical barriers in their environment."
The ability or inability for species to roam can be compromised by human activity, including logging or deforestation. The study could be used to anticipate how these disruptions can affect the habitats of species, researchers said.