A century ago, the Roaring Twenties marked the shaking of social norms, the emergence of new identities, and the redrawing of nations. The decade changed the pace of human lives.
Today, we invite you to revisit the moments in 2020 that made us rethink the very nature of what it means to be human.
Where — and from whom — do we come? Is there a seat of consciousness in our brains? Do we evolve, like other species? In 2020, we came a little closer to finally answering these questions.
For the full list of 2020's most amazing human discoveries, go here.
Vikings may not be who we thought they were, DNA study finds
Ancient Viking warriors steal our modern-day imaginations more than most other ancient peoples.
Brutal, seafaring, and mystical, their society and mythology is the basis of one of the most influential Marvel franchises: Thor. And the actor in the titular role, Chris Hemsworth, is the stereotypical Viking: blond, blue-eyed, built, and tall.
You might say it was in his genes to play Thor. But in truth, Viking genetics tell a much more complex history than popular cultural retellings of their story would have us believe.
In September 2020, the largest-ever Viking DNA study flipped everything we thought we knew about their history on its head.
By sequencing the genomes of more than 400 Viking men, women, and children, scientists revealed this ancient warrior people may have been far more diverse in origin and behaviors than we first thought.
The study rewrites Viking lore, and demonstrates the power of modern-day scientific techniques to cut through the haze of history and reveal the truth about our ancestors.
More ancient ancestors:
In death, one form of sensory perception persists
Our final words to loved ones may not fall on deaf ears.
As humans lay dying, new research suggests one crucial sense is still functioning. The brain still registers the last sounds a person will ever hear, even if the body has become unresponsive.
The study, released in June 2020, suggests hearing is one of the last senses to disappear during death.
Scientists found that the brains of "actively dying" patients in palliative care (some unresponsive, some responsive) still registered activity in response to sounds.
The patterns of activity were similar to those seen in a sample of healthy controls, suggesting people still hear as they die.
There's certainly a difference between hearing something and understanding it. But what we do know from this work is that dying loved ones may hear something if we speak to them.
Ancient sex between different human species influences modern-day health
It was the perfect meet-cute.
Some 100,000 years ago, Homo sapiens and Homo neanderthalensis encountered one another for the first time and got to know each other — intimately.
This genetic intermingling, it turns out, was crucial for giving modern humans some pretty handy genes. By mating with the now-extinct species, we adopted some of their more useful genetic adaptations as our own.
Using new computational methods, scientists determined that the gene flow between archaic humans affects modern-day human metabolism, our response to different types of pathogens, and a scattering of neuronal traits.
These findings make it clear our ancient ancestors had a tangible impact on our physiology — one which persists today.
The more you know:
Scientists discover the roots of consciousness in the brain
Consciousness is an elusive realm of science that has confused and incited scientists for decades.
But a study published in March 2020 uncovered something new and vital about the phenomenon.
It confirmed a notion that had already been conceived: that consciousness is a delicate balancing act between an individual’s self-awareness combined with an awareness of their surroundings — and that this is balance is kept in check by the alternating activation of two neural networks, the default mode network, or DMN, and the dorsal attention network, or DAN.
While this doesn’t solve the mystery of consciousness once and for all, it does make the picture a little less grainy.
One day, the team’s work could be applied to gauge consciousness; for example, to monitor anesthesia during surgery or to come up with treatments for disorders of consciousness.
Treat your brain right:
Neuroscientists uncover how magic mushrooms "rebalance" the brain
There's no reset button on your brain. But the more scientists learn about magic mushrooms, the more we know they're about as close to a reset button as we can get.
Psilocybin — the hallucinogenic chemical in certain mushrooms — can reshape cells in the brain and increasingly shows potential for treating addiction or depression. Now, using new brain models, scientists are getting a better idea of how it all happens.
In a study published in April 2020, researchers created a realistic whole-brain model, also known as a "whole-brain connectome" — basically, a picture of all the neurons ticking away in the brain and the different neurotransmitters they are constantly lugging around. They used this to model how the human brain looks on psilocybin.
The team saw that when psilocybin was introduced, it disrupted networks in the brain — they became “destabilized” — and forced the neurotransmitters to find new pathways between brain cells.
In the future, the team hopes their model could help us learn how we can run different types of software in our brains, and in doing so, help treat conditions like depression.
More drug science:
Ancient human sex changed how some people feel pain
Really, more ancient sex? Yep. 2020.
We probably didn't feel their pain then, but about 0.4 percent of Britons probably feel it now, thanks to a genetic gift from those extinct hominids.
Research published in July 2020 found that some humans still carry the Neanderthal version of the gene SCN9A, which codes for the protein Nav1.7.
This protein, a sodium channel, essentially acts as a pain volume knob, deciding how many painful signals are sent to the spinal cord and brain.
The individuals who carry this variation seemed to have ended up with the short end of the stick. They tend to experience more pain when compared to those without it.
- Amateurs discovered an ancient grave that rewrites history
- Ancient stone tool rewrites a chapter of human history
Looking for more? See the full list of 20 discoveries that redefined humans in 2020 here.
Thank you for reading! Stay turned for another special edition of Inverse Daily coming tomorrow.