Science finds human evolution is speeding up

At a hospital in the year 3000, a mother waits nervously as the doctor examines her newborn child.

Staring at the baby’s squashed face and knobbly feet, the doctor glances over to his chart. So far, so good. Just beneath the surface of the skin, huge arteries pump blood to curiously large hands.

Then, examination complete, the doctor darts across the room on his hoverboard and hands the child to her excited mother. “She’s perfect”, he declares.

Nobody knows exactly what future humans will look like. Indeed, predictions range from the mundane – slightly bluer eyes or darker skin – to the completely bizarre.

Humans could one day grow beaks, making trips to the dentist a thing of the past, predicted biologist Dr Gareth Fraser in 2013. In the same year, neuroscientist Dean Burnett argued that rigid human fingers could slowly evolve into tentacles as touch screens take over the world.

Today, these predictions sound more like science fiction than reality. But while tentacles and beaks may be a long way off, a new study by Australian scientists suggests that more subtle changes in human anatomy may be emerging faster than ever.

The group’s research shows that many babies born today look different to those born only 150 years ago. They have shorter faces, new bones in their feet and legs and an extra artery in their arms.

And their wisdom teeth, once used by ancient humans to chew foliage, are missing.

The scientists call these changes microevolution. “A lot of people thought humans have stopped evolving. But our study shows we are still evolving – faster than at any point in the past 250 years”, says Dr Teghan Lucas, one of the scientists involved in the study.

Dr Lucas and her colleagues believe the changes are occurring because modern humans live in a favourable environment. “We have advanced as a species to the point where natural selection no longer removes the outliers in the gene pool.”

When Charles Darwin proposed the theory of evolution in 1859, only half of British children survived to celebrate their 21st birthday. Today, that figure stands at an astonishing 99%.

Indeed, due to early death or infertility, many ancient humans were not able to reproduce. Now, modern medicine means more people have the chance to pass on their genes.

The result is a series of unexpected changes in the human body – from extra arteries to smaller jaws.

For a long time, scientists thought that evolution was slowing and humans had nearly reached their final form. Then, in 2007, shock research quashed that conventional wisdom.

Humans and chimpanzees separated 6 million years ago. But when American academics analysed DNA samples from the two species, they found fewer differences than they were expecting, indicating that human evolution was slower in the distant past.

In fact, the scientists concluded that over the past 10,000 years, humans have evolved up to 100 times faster than ever before.

Now, a decade later, Dr Lucas believes that the process is accelerating once again.

So, will humans ever stop evolving?

Superhumans

Definitely, say some. Most evolutionary changes happen in small or isolated populations where significant mutations can become established in the gene pool, points out anthropologist Ian Tattersall. Today, mass movement of the human population makes meaningful evolution unlikely. And there is yet another, more terrifying force which may stop human evolution in its tracks – mass extinction.

The opposite is true, say others. The results of the scientific research are clear. Human evolution has sped up, not stopped. In the 1880s, only 10% of babies born retained the extra artery in their arm throughout their life. Today, the figure is 30% and scientists predict that by 2100, a majority will have the blood vessel. As long as humans remain wandering the Earth, evolution will continue.