Many people think of evolution as a thing of the past. Something that started billions of years ago with single-celled organisms and ended with modern humans. But that could not be farther from truth. Contrary to popular belief, humans have not stopped evolving. It is still happening and we are actively changing. And it is possible that it is happening faster than ever. Let’s take a look at the scientific evidence for this.
Let’s start with the human eye. Not the inner workings of the eye, but the colour of it. Roughly 17% of the world’s population has blue eyes. But 10,000years ago people with blue eyes were unheard of. Researchers believe that blue eyes come from a mutation in a single ancestor between 6000-10,000 years ago. When one recognises that modern humans have existed for much longer than that, it is clear that evolution could not have stopped with the rise of humanity.
And what about the brain? It turns out that our brains have actually been shrinking over the last 30,000 years. The average volume of the human brain has decreased form 15000 cubic centimetres to 150 cubic centimetres. That is a reduction in size of 10%.
About the teeth—For example, wisdom teeth. They are the last set of morals in our mouths, and they were helpful to our early ancestors who are tough, uncooked foods, that wore away their teeth. But today thanks to cooking and cutlery, our food has become softer and easier to chew. As a result, our jaws have become much smaller and there is not just enough room left for the wisdom teeth anymore. According to some estimates, 35% of the population now are born without wisdom teeth. Some researchers believe that wisdom teeth will eventually disappear altogether. Those of us who sill grow wisdom teeth, often have to surgically remove them.
As evolution continues, it is likely that the humans of the future will not have to deal with this painful struggle.
We can even see traces of human evolution in our lungs. People who are native to Tibet are able to live in the Himalayan Mountains with low oxygen levels, but it is ot that they are just used to it. But living with low oxygen levels over several generations has led to mutations in their genes. As a result of this genetic evolution, Tibetan people’s blood produces more of the oxygen-transporting protein called haemoglobin.
What is precisely more fascinating than all of this is that, evolution in humans appears to be speeding up. In the past 5000 years, humans have evolved up to 100 times more quickly than at any time in last 6 million years. The widespread assumption is that human evolution has slowed down because we have conquered nature, is absolutely not correct. Rather we simply have developed ways to curate our surrounding and experiences to our liking.
Many Chinese and African adults cannot digest lactose and milk, but in Europe the situation is reverse. Another reason we are seeing an increase in evolutionary speed is the rise in global population. As the population grows, humans are reproducing more frequently, and that means mutations are able to be passed on.
Evolutions in humans probably won’t stop any time soon. In fact, it will likely continue on until humans become something else entirely.