Incredible Resilience Displayed: Individuals on Earth Capable of Consuming Toxins and Barely Surviving Breathing Processes
Human evolution ain't done jogging, mate. Without a doubt, Mother Nature started molding us long ago when we exited our African home and wandered across the globe. She tailored us with natural selection to adapt to each environment we inhabited.
Recent research by Harvard Medical School scientists has revealed the presence of 347 locations in the human genome where natural selection occurred as our ancestors migrated out of Africa and adapted to different environments.
Speaking of remarkable adaptations, check out the folks in Bolivia. They live in areas with arsenic-rich soils and water, which is lethal to most of us but doesn't even phase them. Not only do they manage to ingest this poison daily, but some have also developed enzymes that break down arsenic in the liver, making it harmless. This adaptation came into being about 7,000 years ago due to natural selection, and it's been a standard in their genetic makeup ever since.
Tibetans are another group that's got some serious evolutionary superpowers. Living above 4,000 meters, they've got half the oxygen that those at sea level get. But they compensate for this by increasing blood flow to their vital organs. Using special devices, researchers discovered that Tibetans circulated blood twice as much as average people, with no difference in heart rate or blood pressure.
The secret behind this incredible blood flow is nitric oxide and its metabolites, which cause their blood vessels to dilate, like a full-body "viagra" effect. Analysis of their blood revealed that Tibetans have ten times higher concentrations of these metabolites compared to lowlanders.
The genius adaptation: Tibetans evolved to deliver more oxygen to their internal organs without increasing hemoglobin levels, which would have made their blood too thick, putting a heavy strain on their hearts.
Last but not least, there are the Bajau people in the Pacific, who can dive to depths of 70 meters without the need for scuba gear, holding their breath for 13-15 minutes on a single breath. What's their secret? Their spleens, my friend. Compared to nearby Saluan people, the Bajau's spleens are larger on average, and in some cases, up to 2-3 times larger.
Having larger spleens not only stores more oxygen but also makes the process of oxygenating blood about 10% more efficient than their land-dwelling counterparts. The Bajau's adaptations are primarily due to a mutation in a gene that regulates thyroid hormone levels, which directly influences spleen size.
All told, scientists discovered more than twenty variations of genes that distinguish the Bajau from their terrestrial neighbors. At depth, their hearts slow down, their blood vessels contract, and their eyes "see" underwater as clearly as we do above water.
So there you have it, mate—people are adapting like crazy, and it's all thanks to natural selection. It's clear that evolution is still going strong, and it'll be fascinating to see what changes arise next!
Bonus Info:- Drinking milk? Yeah, that's a mutation too. Around 5,000 years ago, people didn't drink milk in adulthood. But after the development of animal husbandry, a gene variant that maintained lactase production in adults emerged. This mutation was linked to women, who passed down these beneficial gene changes through generations.
- Women drive natural selection. A study done in Tibet uncovered that women who adapted better to high altitudes had more children. The more offspring a woman had, the higher the chance her children would inherit these genetic adaptations and pass them on.
- Science has proven that human evolution continues, as we adapt to various ecosystems, such as the health-and-wellness practices that arise from our connection with Mother Nature.
- Intriguingly, recent research in environmental-science reveals that natural selection played a significant role in the adaptation of humans when they migrated out of Africa.
- The studies at Harvard Medical School discovered over 300 locations in the human genome where natural selection occurred, demonstrating our remarkable ability to adapt to diverse climates and lifestyles.
- Fitness-and-exercise enthusiasts might find it fascinating to learn about the folks in Bolivia, who have developed an enzyme that breaks down arsenic in their livers due to natural selection.
- Climate-change is not our only challenge, as the Tibetans have adapted to live in low-oxygen environments with remarkable blood flow and oxygen storing capabilities in their spleens.
- Space-and-astronomy aficionados should take note of the Bajau people, who have evolved to dive significantly deeper than others, with larger spleens for more efficient oxygen use – a marvel of natural selection.
- Food-and-drink choices, such as consuming milk, can also be traced back to gene mutations that emerged around 5,000 years ago, thanks to human adaptability and natural selection.
- From pets to travel, it is evident that relationships with each other, our environment, and even our companions have been shaped by natural selection, driving the evolution of human traits over time.
- As we continue to explore the mysteries of our planet, technology will undoubtedly play a vital role in uncovering more examples of human adaptations, illuminating the marvels of natural selection and our evolving world.
