An English anthropologist says she’s proven Darwin’s theories about species and subspecies.Understanding how species become subspecies and then new species can help evolutionary scientists.Naturalists, scientists who document species, have worked for centuries using whatever the contemporary tools were.
An anthropology doctoral student at the University of Cambridge has analyzed centuries of naturalist data to prove a longstanding theory from Charles Darwin’s work. The crux of the work is in the relationship between how species evolve into subspecies and whether that presages new species.
Laura van Holstein said in a statement that the way subspecies emerge depends on whether the species is by land, by air, or by sea. “Subspecies form, diversify and increase in number in a different way in non-terrestrial and terrestrial habitats, and this in turn affects how subspecies may eventually become species,” she said.
We see this kind of branching represented in concurrent species, like the isolated and specialized groups of finches Darwin himself studied in the Galapagos Islands. One of the most familiar examples might be the wildcat, which refers to one of two species that are very closely related—domestic cat ancestor the African wildcat, and the European wildcat. In turn, each species has subspecies. These are all totally separate from specific kinds of wild cats like Pallas cats or fishing cats.
Darwin was working from his own observations and studies, but van Holstein has synthesized centuries of previous naturalist data into one cohesive explanation that she says proves Darwin’s theories. Civilians have long wondered if the way humans have collapsed many species’s habitats is causing differences in evolution—whether shortening the time frame that species evolve with new mutations or branching different groups into new species more quickly.
This research says that’s likely the case, and suggests environmental activists trying to protect habitat or slow climate change can choose where to focus based on how species are being affected most.
“The impact on animals will vary depending on how their ability to roam, or range, is affected,” van Holstein said. “Animal subspecies tend to be ignored, but they play a pivotal role in longer term future evolution dynamics.”
In the past, naturalists often worked by traveling and documenting everything they saw, writing detailed and uniform descriptions and drawing or watercoloring specimens. They’d travel for months or years to distant places and preserve plant specimens to bring back. Preserved animals became huge draws in museums, offering regular people their only chance to see some kinds of exotic creatures up close.
This means there’s a rich history in the form of surviving documents from these naturalists, creating a visual and taxonomical history that researchers like van Holstein can use. Naturalists are considered scientists, the same way a taxonomist is part of a subset of biologists. But their work was often extremely dangerous—and it still is.
Modern naturalists have a different scope of work, from using cameras and smartphones to negotiating war zones or disputed territories. Today, biodiversity scientists often carry this mantle, helping to validate discoveries of new species and specializing in the distinct ecosystems van Holstein has shown play a huge part in how species fracture, emerge as subspecies, and evolve. Check out the massive Biodiversity Heritage Library for naturalist illustrations and documents going back to the 1400s.