Ongoing Evolution

EVOLUTION: Biology. Change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift.

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150-years ago Charles Darwin published his masterwork, On the Origin of Species, and the religious community has been all a-twitter ever since.

As much as I'd enjoy debating evolution vs. intelligent design with a fanatic, this piece just isn't about that. It's about evolution - or more to the point, the ongoing evolution which is taking place, here and now, all around us. And yeah, that includes Man.

For decades preeminent biologists have held the view that any significant evolution hadn't occurred for many thousands of years, and that human evolution in particular had become all but irrelevant since the emergence of Homo sapiens 50,000 years ago. But, the fact is, humans are still evolving, and the evolutionary changes taking place at this very moment are undeniable.

Below, are just two staggering examples that evolution is indeed marching on.

The Humble Earthworm: Eco-Warrior

An abandoned copper mine contaminated by run-off from industrial waste is being reclaimed by an unusual army of eco-warriors: metal-eating earthworms. Deposits of metal at sites where these worms are found creates a unique evolutionary event, yielding organisms that thrive in highly polluted environments.

"If you took an earthworm from the back of your garden and put it in these soils, it would die," said researcher Mark Hodson of the University of England in Reading.

Discovered in abandoned mines in England and Wales, these highly evolved superworms devour toxic heavy metals like lead, arsenic and copper. DNA analysis of lead-tolerant worms revealed subtle changes in the worms' make-up that were induced by the metals, and sensitive X-rays technology was used to track how the worms metabolized metal particles one-thousandth the size of a grain of salt. "These earthworms have developed adaptive mechanisms for dealing with the soil pollution," Mark Hodson says."When they ingest the soil, the metal accumulates in their tissues. But they have modified calcium pathways and secrete an enzyme that converts the metal into a less toxic form."

When the worms process the polluted soil, they excrete a slightly different version that is easier for plants to absorb. Eventually, we might be able to recruit these earthworms to accelerate the remediation process and to clean up contaminated sites.

Man: Evolving to Survive

Malaria is about 35,000 years old, with the most lethal form of it just 5,000 years old. Yet in sub-Saharan Africa and other regions where it is endemic, people have developed at least 25 new genes that protect against malaria ... including the Duffy blood type (or DARC gene) , an entirely new blood group.

More recently HIV resistance has appeared due to a genetic mutation now found in 10% of Europeans. Scientists speculate that the variant may have originally evolved as a protection against smallpox.

Paralleling the constant battle against pathogens, human sperm is evolving at higher speed, driven by the race to get to the egg before another man's sperm. And at the other end of human life span, genes which help us live longer are being selected. Evolutionary biologists previously believed that the elderly do not contribute to the gene pool and were hence invisible to natural selection, but studies have shown that children doted on by their grandmother are more likely to survive and pass on their grandmother's genes for longevity. The phenomenon is known as the "grandmother effect."

To many evolutionary biologists, suggesting that humans have undergone an evolutionary makeover from the Stone Age to present day would be nothing short of blasphemous. But modern research is doing just that. They've found an abundance of recent adaptive mutations etched in the human genome and, even more shocking, these mutations seem to be piling up faster and faster, like an avalanche of evolution. Their data shows that over the past 10,000 years human evolution has occured a hundred times more quickly than in any other period in our species' history.

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I know it sometimes seems that the race of Man is determined exterminate itself. With our bloodlust for wars and killing, our ongoing destruction of our own environment, emerging supergerms due to our overuse of antibiotics, and so on, and so on ... But, to paraphrase Jeff Goldbloom in Jurassic park - Life, it would seem, is finding a way.

You can read more about this and related articles at DiscoverMagazine's Website

There's an incredible video series by the BBC titled "Journey of Life" after the comments - if you're so inclined ...