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September 09, 2021

 

Increasingly Humans are developing a new artery, indicating that we are still evolving.

When imagining how our species could look in the future, it's common to get carried away with details like height, brain size, and skin colour. Even now, minor changes in our body show how unpredictable evolution may be.

Consider something as simple as an extra blood vessel in our arms, which, if current trends continue, may become commonplace in a few generations.

According to researchers from Flinders University and the University of Adelaide in Australia, an artery that runs down the centre of our forearms while we're still in the womb isn't disappearing as frequently as it used to.

That implies there are more adults than ever before who have an extra vascular channel running beneath their wrist.

In 2020, Flinders University anatomist Teghan Lucas remarked, "Anatomists have been investigating the incidence of this artery in people since the 18th century, and our work indicates it's obviously rising."

"When it comes to evolution, the prevalence was around 10% in people born in the mid-1880s compared to 30% in people born in the late 20th century, so that's a huge increase in a relatively short period of time."

Three major arteries in the forearm - median in the center. (ilbusca/Digital Vision Vectors/Getty Images)


The median artery, which transports blood down the centre of our arms to feed our growing hands, originates quite early in the development of all humans.

It normally regresses after eight weeks, leaving the job to two other vessels: the radial (which we can feel when taking a person's pulse) and the ulnar.

Anatomists have known for a long time that the median artery's withering isn't a guarantee. It may linger for another month or so in certain circumstances.

It may still be pumping when we're born, nourishing either just the forearm or, in some cases, the hand as well.

Lucas and colleagues Maciej Henneberg and Jaliya Kumaratilake from the University of Adelaide analysed 80 limbs from cadavers given by Australians of European heritage to compare the prevalence of this persisting blood channel.

On passing, the donors ranged in age from 51 to 101, indicating that they were nearly all born in the first half of the twentieth century.

The researchers recorded how often they came across a chunky median artery capable of delivering a good supply of blood and compared the statistics to records gleaned from a literature search, taking into account tallies that would over-represent the vessel's appearance. Their findings were published in the Journal of Anatomy in 2020.

The fact that the artery is three times as frequent in adults now as it was more than a century ago is a remarkable discovery that implies natural selection favours individuals who keep this extra bit of blood flow.

"This rise could have been caused by changes in genes involved in median artery formation, or health issues in mothers during pregnancy, or both," Lucas adds.

We could suppose that having a long-lasting median artery would provide a steady supply of blood to dexterous fingers and powerful forearms long after we were born. However, having one puts us at a higher risk of developing carpal tunnel syndrome, a painful ailment that limits our ability to use our hands.

It will take a lot more detective work to figure out what kinds of factors play a big part in the processes that lead to a persistent median artery.

Whatever they are, we are sure to see more of these vessels in the future years.

"By 2100, the majority of people will develop median artery disease of the forearm," Lucas said.

The reemergence of a knee bone called the fabella, which is also three times more prevalent today than it was a century ago, parallels the dramatic increase of the median artery in adults.

Small microevolutionary changes add up to large-scale variances that identify a species, no matter how minor they are.

Together, they produce new pressures, leading us down new paths of health and sickness that we may find difficult to envisage right now.


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April 16, 2018
Earth's magnetic field is pretty adept at flipping polarity. The poles have swapped, reversing north and south, many times over the planet's history.

Within the last 20 million years, Earth has fallen into the pattern of pole reversal every 200,000 to 300,000 years, and between successful swaps, the poles sometimes even attempt to reverse and then snap back into place.
About 40,000 years ago, the poles made one such unsuccessful attempt, and the last full swap was about 780,000 years ago, so we're a bit overdue for a pole reversal based on the established pattern.
The planet's magnetic field is already shifting, which could signify the poles are preparing to flip, and while we can't yet confirm that a reversal is on the near horizon, it is well within the realm of possibility.
While a pole reversal isn't entirely uncommon when you consider Earth's history, this time it could have serious implications for humanity.
To try to determine whether or not a flip is imminent, scientists have begun using satellite imagery and complex calculations to study the shifting of the magnetic field.
They've found that molten iron and nickel are draining energy from the dipole at the edge of the Earth's core, which is where the planet's magnetic field is generated.
They also found that the north magnetic pole is especially turbulent and unpredictable. If the magnetic blocks become strong enough to sufficiently weaken the dipole, the poles will officially switch.
Again, while it is not a certainty that the switch will happen soon, this activity at the Earth's core suggests that it is possible in the near future. So, how might a pole switch impact our lives?
The Earth's magnetic field protects the planet from solar and cosmic rays. When the poles switch, this protective shield could diminish to as little as one-tenth of its typical ability.
The switching process could take centuries, and the entire time, radiation would be able to get closer to the planet than usual.
Eventually, this radiation could reach the surface of the Earth, rendering some regions uninhabitable and causing entire species to go extinct.
Before that happened, though, a weakened magnetic field would likely impact orbiting satellites, which have suffered from memory failure and other damagewhen exposed to such radiation in the past.
Damage to satellites caused by decreased protection from the magnetic field could affect the satellite timing systems that control electric grids.
These grids could fail, leading to worldwide blackouts that experts predict could last for decades.
Without functioning electric grids, we couldn't use cell phones, household appliances, and so much more. The sudden blackouts would have hospitals scrambling for backup power sources, putting countless lives at risk.
GPS technology would also be compromised, affecting everything from military operations to our ability navigate our cars.
Additionally, we are becoming more reliant on technology by the day, with autonomous vehicles, artificial intelligence (AI), and other innovations all advancing rapidly.
By the time a pole switch did take place, these innovations could be a regular part of our daily lives, furthering the potential for disruption.
It's true that we live in an age where data rules all. From how we communicate to how we get around to how our governments and critical facilities run, it all comes down to how we send and store data, so if the world's satellites are damaged or rendered nonfunctional, life as we know it could forever change.
But this isn't a doomsday prediction. While the poles will inevitably flip again at some point, our ability to recognise this possibility in advance allows us to prepare for it.
For starters, satellite companies can begin to collaborate, sharing ideas with one another on how to equip satellites to deal with a pole reversal.
Government and university researchers can focus their efforts on developing new satellites specifically designed to withstand extreme radiation and space weather.
Governments, businesses, and communities can come together to form action plans.
They can find ways to store energy and ensure the public is educated on the subject of pole reversal, so that when it happens, the situation won't cause widespread panic.
Earth's poles have been switching for millions of years, and they will continue to do so for the foreseeable future. The best thing we can do is prepare now so we're ready the next time it happens.
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October 22, 2016
Stephen Hawking

In a lecture at the University of Cambridge this week, Stephen Hawking made the bold claim that the creation of artificial intelligence will be "either the best, or the worst thing, ever to happen to humanity".
The talk was celebrating the opening of the new Leverhulme Centre of the Future of Intelligence, where some of the best minds in science will try to answer questions about the future of robots and artificial intelligence - something Hawking says we need to do a lot more of.
“We spend a great deal of time studying history," Hawking told the lecture, "which, let’s face it, is mostly the history of stupidity."
But despite all our time spent looking back at past errors, we seem to make the same mistakes over and over again.
"So it’s a welcome change that people are studying instead the future of intelligence," he explained.
It's not the first time Hawking has been worried about artificial intelligence.
Last year, he joined Elon Musk and hundreds of other experts in writing an open letter asking the governments to ban autonomous weapons that might one day be able to turn against humans.
He's also previously said that "the development of full artificial intelligence could spell the end of the human race".
In Wednesday's lecture, he admitted he was still worried about "powerful autonomous weapons" and "new ways for the few to oppress the many", which come with artificial intelligence.
But he said if we can think about and address these issues now, the technology also has the potential to do good.
"We cannot predict what we might achieve when our own minds are amplified by AI," he said.
"Perhaps with the tools of this new technological revolution, we will be able to undo some of the damage done to the natural world by the last one – industrialisation. And surely we will aim to finally eradicate disease and poverty."
The Leverhulme Centre of the Future of Intelligence at the University of Cambridge, where Hawking is also a professor, has received more than US$12 million (£10 million) in grants to run research projects that will enhance the future potential of artificial intelligence, while carefully addressing the risks.
The centre was inspired partly by the university's Centre for Existential Risk, which already offers courses in subjects such as "Terminator Studies", in order to examine future potential problems for humanity.
While that centre focusses on a range of threats - such as climate change and war - the new Leverhulme Centre will look specifically at the issues that could arise from machines that think and learn like humans.
"Machine intelligence will be one of the defining themes of our century, and the challenges of ensuring that we make good use of its opportunities are ones we all face together," said director of the Leverhulme Centre, Huw Price.
"At present, however, we have barely begun to consider its ramifications, good or bad."
With Google already developing artificial intelligence that can learn from its own memory; Elon Musk worrying about humans become the dumb "house pets" of AI in the future; and computer systems already rivalling four-year-olds in IQ tests, it's definitely something worth thinking about sooner rather than later.

As Hawking says, it might end up being "crucial to the future of our civilisation and our species".
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