Populations in Africa, for example, are rapidly expanding so those genes increase at a higher frequency on a global population level. Areas of light skin colour are reproducing at lower rates. Therefore, Hodgson predicts, skin colour from a global perspective will get darker.
And what about space? If humans do end up colonising Mars, what would we evolve to look like? With lower gravity, the muscles of our bodies could change structure.
Perhaps we will have longer arms and legs. In a colder, Ice-Age type climate, could we even become even chubbier, with insulating body hair, like our Neanderthal relatives? Worldwide there are roughly two new mutations for every one of the 3. Which is pretty amazing - and makes it unlikely we will look the same in a million years. Your information will be used in accordance with our privacy policy.
You can unsubscribe at any time. Although we have smaller jaws than in the past, and less room for all 32 adult teeth, it is probable that no significant change will occur in the number of teeth. However, if we change the way we eat perhaps food in the future will be softer and require less chewing then we may see some reduction in our jaws and more crowded teeth.
The pelvis is a compromise between an upright posture, bipedalism and the size of the birth canal. Although the past trend within our species has generally been toward smaller brains, this was probably due to a decrease in body size.
We may not use all of our brain today, but for a smaller brain to become common in our species there would have to be an advantage in such a characteristic. There is a direct relationship between our brain size and body size and this relationship is unlikely to change. The trend over the last years has been toward larger bodies, but this cannot continue indefinitely.
Size cannot increase beyond a certain limit as the mechanical demands on the tissues of very large bodies are different to bodies of medium sizes.
By significantly changing the size of the body, there would need to be a change in the shape of the body. Recent reports show that there's a whole generation of teenagers with overdeveloped thumbs due to playing too many video games. Muscles are able to adapt through excessive physical use, but this is not genetic. An individual may develop such a characteristic but will not pass this on to any offspring. Many geneticists claim that something new is happening in human evolution - something along the lines of a 'grand averaging' of our species.
Basically, we are becoming more alike. If both populations survived long enough — much more than , years — we might see divergence and maybe two species of humans. We might get the evolution of new human species if we colonise other planets where people have to adapt to an alien environment.
Mars, for example, is further away from the sun so residents there may evolve bigger eyes to see better in the dimmer light. And without life, Mars is essentially a sterile environment and this may make Martian colonists more susceptible to disease so that mixing with people on Earth is discouraged.
This could rule out sex and increase the chance the colonists would develop into a new species. However, such speciation might happen if we stay on Earth too. This might bestow an advantage like longer life to the individual and their children.
This process is started artificially by tinkering with genes, but reinforced and consolidated by cultural differences. Homo sapien s split from Neanderthals at least , years ago, when Neanderthals moved into Europe and Asia, while H. Yet, when the two subspecies met again hundreds of thousands of years later, they were still able to interbreed. Even if we could spread to other planets and interstellar travel took thousands of years, this is still a short period compared with the time required for the evolution of new species.
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