<![CDATA[io9: speciation]]> http://tags.lifehacker.com/assets/base/img/thumbs140x140/io9.com.png <![CDATA[io9: speciation]]> http://io9.com/tag/speciation http://io9.com/tag/speciation <![CDATA[Species Diversity Not Caused By Environment]]> Accepted scientific wisdom holds that new species arise because of geographic separation - the same bird evolves differently on two different islands. But a new study overturns this idea, challenging the importance of environment as a driver of evolution.

Published this week in Nature, the new study shows that even when a group of creatures is not separated by mountain ranges, and isn't forced to find a niche in the ecosystem via natural selection, new species will evolve over hundreds of generations. The researchers created a mathematical model of speciation, when one species evolves into many, which tracks emergence of species over 2,000 generations. The model was based on scientific observation of how new species have evolved all over the Earth.

Above, you can see the model, showing how species transform over time. Each color represents a species. What begins as a uniform single-color group slowly evolves into several distinct species. But this occurs via mutation and sexual selection, not from the creatures growing distant from each other geographically. And not from competing for different niches in the environment. In this model, there are no niches and no geographical boundaries.

So what's the big deal? In short, it means that new species can arise without competion for environmental resources. Sexual selection alone is enough to produce species diversity.

According to the New England Complex Systems Institute, which funded the study:

The study found that over generations the genetic distance between organisms in different regions increases, and groups of organisms spontaneously form groups that can no longer mate, causing a patchwork of species across the area. The number of species increases rapidly until it reaches a relatively steady state.

"One can think about the creation of species on the genetic level in the same way we think about the appearance of many patterns, including traffic jams," said [researcher] Yaneer Bar-Yam. "While the spatial environment may vary, specific physical barriers aren't necessary. Just as traffic jams can form from the flow of traffic itself without an accident, the formation of many species can occur as generations evolve across the organisms' spatial habitat."

The study authors are not claiming that enviroment is unimportant. They are simply saying that under some circumstances, it is not a necessary ingredient for evolutionary transformation.

Nevertheless, this study overturns the typical view of evolution. It turns out that we don't need adaptation to a hostile natural environment to evolve new forms of life. We can do it just by having offspring and mutating over time.

via Nature and New England Complex Systems Institute

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<![CDATA[Has a New Species of Insect Appeared in the Middle of London?]]> When an unknown insect starts showing up in ever-growing numbers in London, England, the most logical step would be to take one to some experts so they can identify it. What do you do when the insects first appear in the experts' own back yard, the Wildlife Garden outside the Natural History Museum? Even after checking it against the museum's collection of 28 million bug specimens, no one is sure what species this is. How could an entire species go undetected in an urban area until now? Or, stranger still, what could cause a totally new species to appear and flourish like this?

The bugs are tiny, roughly rice-sized, and they feed on the seeds of plane trees. They probably don't pose a serious threat, although invasive species are never good news, if that's what they turn out to be. Their numbers are increasing steadily, and they've already been found beyond the museum's grounds. Entymologists thought they had a match with Arocatus roeselii, a central European insect that lives near alder trees, but Arocatus roeselii has a reddish coloration.

Experts with the museum think the bugs might be Arocatus roeselii that moved in and flourished without their natural predators, but they've left open the possibility that these bugs are an entirely new, undiscovered species of insect. Why they suddenly appeared in the middle of a major city is unknown. If anyone can come up with a good explanation, it's the io9 readers. Can you come up with some totally implausible (or totally plausible, for you hard SF sticklers) reasons for the presence of these alien bugs? Image by: BBC News.

Mysterious insect baffles experts. [BBC News]

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