Trivia nights would have been a lot easier 300 million years ago. In the Early Permian Epoch, Earth had one just one ocean, Panthalassa, with one massive supercontinent in it, Pangea.
Pangea is just one of several supercontinents our planet has created over its 3.5 billion year history. They form as Earth's tectonic plates slide over its mantle, a process that breaks up landmasses and reforms them in new combinations—which is why geologists just found a chunk of Canada sticking to Australia, or why fossils of Lystrosaurus, a stocky, pig-like reptile, are found in the very separate locations of Antarctica, India and South Africa, and nowhere else. The slow grind of continents is imperceptible to us, but it is happening right this minute. “Continents on these plates typically move, I would say, at the rate your fingernails grow," geologist Ross Mitchell tells NPR.
Where were we 300 million years ago?
Absolutely nowhere—life on Pangea was human-free (pause for wistful thinking), but when we puzzle-fit the modern continents back to where they were 300 million years ago, it reveals how your country may have shared its borders with some very different neighbors.
This conceptual map called 'Pangea Politico' was designed by amateur cartographer Massimo Pietrobon to show how different the world would be if Pangea hadn't broken up some 200 million years ago. Pietrobon's map is more about politics than total geological accuracy, so the scales of some nations aren't perfect, but it shows the approximate location of how our modern world sat atop the old tectonic plate arrangement.
To zoom, click the map. Image credit: Massimo Pietrobon.
With great gusto, Pietrobon describes an ancient world where America and Russia are cozier neighbors, Santa Claus lives in South Korea, Cuba is land-locked, and Antarctica and India share the same climate. As translated (imperfectly) from Italian:
“And so the United States find themselves in front of the muzzle all the Arabs, while in the south they border directly with both Cuba and Colombia!
We Europeans, on the other hand, find Africa at home at last. Enough of the thousands of deaths at sea to get to Europe, now they get there by bike!
Again, finally, African Americans get together with their African cousins tout-court and can visit them by bus.
Not only that, the Moroccans will finally lead to Quebec on foot!"
'Pangea Politico' makes a timely and ultimately humanitarian statement about our borders and political feuds. “Gathering the world in one piece of land represents a return to the unity of the planet, to the unity of the human race, in spite of the divisions that are so convenient for our rulers!" writes Pietrobon.
Taking a long view of geology results in the same epiphany astronauts experience when they look at our pale blue dot from way out there. As Apollo 14 astronaut Edgar D. Mitchell famously said: “From out there on the moon, international politics looks so petty. You want to grab a politician by the scruff of the neck and drag him a quarter of a million miles out and say, “Look at that, you son of a bitch."
Where will we be 250 million years from now?
So we've seen the past in Pangea. What about the future? Current plate movements are slowly reshaping the world once again. Africa is on a collision course with southern Europe, as is the Australian Plate with Southeast Asia. Over the next 250 million years, it's very likely Earth will form another supercontinent of epic proportions, although experts disagree on exactly how it will come together—will it be Amasia, Pangea Proxima, or Novopangaea? Whether that landmass is a human-free place too is anyone's guess, but if so, let's hope it's for the right reasons and not the wrong ones.
Amasia forming over the North Pole. Source: Yale University, Nature
Reactive oxygen species (ROS) accumulate in the gut of sleep-deprived fruit flies, one (left), seven (center) and ten (right) days without sleep.
- A study provides further confirmation that a prolonged lack of sleep can result in early mortality.
- Surprisingly, the direct cause seems to be a buildup of Reactive Oxygen Species in the gut produced by sleeplessness.
- When the buildup is neutralized, a normal lifespan is restored.
We don't have to tell you what it feels like when you don't get enough sleep. A night or two of that can be miserable; long-term sleeplessness is out-and-out debilitating. Though we know from personal experience that we need sleep — our cognitive, metabolic, cardiovascular, and immune functioning depend on it — a lack of it does more than just make you feel like you want to die. It can actually kill you, according to study of rats published in 1989. But why?
A new study answers that question, and in an unexpected way. It appears that the sleeplessness/death connection has nothing to do with the brain or nervous system as many have assumed — it happens in your gut. Equally amazing, the study's authors were able to reverse the ill effects with antioxidants.
The study, from researchers at Harvard Medical School (HMS), is published in the journal Cell.
An unexpected culprit
The new research examines the mechanisms at play in sleep-deprived fruit flies and in mice — long-term sleep-deprivation experiments with humans are considered ethically iffy.
What the scientists found is that death from sleep deprivation is always preceded by a buildup of Reactive Oxygen Species (ROS) in the gut. These are not, as their name implies, living organisms. ROS are reactive molecules that are part of the immune system's response to invading microbes, and recent research suggests they're paradoxically key players in normal cell signal transduction and cell cycling as well. However, having an excess of ROS leads to oxidative stress, which is linked to "macromolecular damage and is implicated in various disease states such as atherosclerosis, diabetes, cancer, neurodegeneration, and aging." To prevent this, cellular defenses typically maintain a balance between ROS production and removal.
"We took an unbiased approach and searched throughout the body for indicators of damage from sleep deprivation," says senior study author Dragana Rogulja, admitting, "We were surprised to find it was the gut that plays a key role in causing death." The accumulation occurred in both sleep-deprived fruit flies and mice.
"Even more surprising," Rogulja recalls, "we found that premature death could be prevented. Each morning, we would all gather around to look at the flies, with disbelief to be honest. What we saw is that every time we could neutralize ROS in the gut, we could rescue the flies." Fruit flies given any of 11 antioxidant compounds — including melatonin, lipoic acid and NAD — that neutralize ROS buildups remained active and lived a normal length of time in spite of sleep deprivation. (The researchers note that these antioxidants did not extend the lifespans of non-sleep deprived control subjects.)
Image source: Tomasz Klejdysz/Shutterstock/Big Think
The experiments
The study's tests were managed by co-first authors Alexandra Vaccaro and Yosef Kaplan Dor, both research fellows at HMS.
You may wonder how you compel a fruit fly to sleep, or for that matter, how you keep one awake. The researchers ascertained that fruit flies doze off in response to being shaken, and thus were the control subjects induced to snooze in their individual, warmed tubes. Each subject occupied its own 29 °C (84F) tube.
For their sleepless cohort, fruit flies were genetically manipulated to express a heat-sensitive protein in specific neurons. These neurons are known to suppress sleep, and did so — the fruit flies' activity levels, or lack thereof, were tracked using infrared beams.
Starting at Day 10 of sleep deprivation, fruit flies began dying, with all of them dead by Day 20. Control flies lived up to 40 days.
The scientists sought out markers that would indicate cell damage in their sleepless subjects. They saw no difference in brain tissue and elsewhere between the well-rested and sleep-deprived fruit flies, with the exception of one fruit fly.
However, in the guts of sleep-deprived fruit flies was a massive accumulation of ROS, which peaked around Day 10. Says Vaccaro, "We found that sleep-deprived flies were dying at the same pace, every time, and when we looked at markers of cell damage and death, the one tissue that really stood out was the gut." She adds, "I remember when we did the first experiment, you could immediately tell under the microscope that there was a striking difference. That almost never happens in lab research."
The experiments were repeated with mice who were gently kept awake for five days. Again, ROS built up over time in their small and large intestines but nowhere else.
As noted above, the administering of antioxidants alleviated the effect of the ROS buildup. In addition, flies that were modified to overproduce gut antioxidant enzymes were found to be immune to the damaging effects of sleep deprivation.
The research leaves some important questions unanswered. Says Kaplan Dor, "We still don't know why sleep loss causes ROS accumulation in the gut, and why this is lethal." He hypothesizes, "Sleep deprivation could directly affect the gut, but the trigger may also originate in the brain. Similarly, death could be due to damage in the gut or because high levels of ROS have systemic effects, or some combination of these."
The HMS researchers are now investigating the chemical pathways by which sleep-deprivation triggers the ROS buildup, and the means by which the ROS wreak cell havoc.
"We need to understand the biology of how sleep deprivation damages the body so that we can find ways to prevent this harm," says Rogulja.
Referring to the value of this study to humans, she notes,"So many of us are chronically sleep deprived. Even if we know staying up late every night is bad, we still do it. We believe we've identified a central issue that, when eliminated, allows for survival without sleep, at least in fruit flies."
