Life On Mars: Colonists Could Evolve Quickly, Become Separate Human Species

When humans eventually get to Mars and establish a colony, one scientist believes the living conditions indemic to the Red Planet will, over time, force the people there to evolve into a separate human species. And in the general evolutionary scale of things, the evolution would occur fairly quickly.

While many scientists worry about just getting humans to Mars, evolutionary biologist Scott Solomon of Rice University ponders what might happen to the humans that have already made the journey, established a colony, and thrived. How would this outpost of humanity be different than, say, the colonies of America or Australia hundreds of years ago? And given the conditions humans would have to endure to survive on Mars, how would that affect the colonists over an extended period of time?

Solomon, author of Future Humans: Inside the Science of Our Continuing Evolution, wrote on Nautilus (per Sputnik News) that human colonists on Mars could very well diverge and evolve into an entirely new species of humans. He bases the suggestion on the colonists on Mars being subjected to the “founder effect,” a phenomenon whereby a species adapts quickly to a new environment. But Solomon also thinks that on the Red Planet the rate of evolution might become accelerated.

“This happens routinely to animals and plants isolated on islands — think of Darwin’s famous finches. But while speciation on islands can take thousands of years, the accelerated mutation rate on Mars and the stark contrasts between conditions on Mars and Earth, would likely speed up the process.”

Solomon points out that evolving “quickly” is relative, considering that the evolution of new species usually takes millions of years. Still, the founder effect could push humans to adapt and evolve in “just a few hundred generations, perhaps as little as 6,000 years.” The conditions that would contribute to eventually creating a separate human species, among others, would include the thin Martian atmosphere, the effects of the gravity on the colonists and their progeny, and the effects of the various forms of radiation that constantly bombards the planet.

The surface radiation of Mars is extreme compared to that of Earth and colonists will not escape all of it, no matter how well protected they might be against it. Although the radiation, which a colonist in just 500 days will experience six times the amount safely allowed workers for the U.S. Department of Energy in a year, can and will cause disease, but Solomon suggests that the radiation will also promote rapid evolution because of the increase in genetic variance.

One of the alterations might present itself in how the Mars colonists’ skin evolves to accommodate the radiation. This could happen to two ways. Colonists will eventually have skin far darker than anyone on Earth due to an increase in the production of melanin or the body will alter itself to produce another skin coloration. (Solomon suggests orange skin derived from the production of pigment from carotenoid, which produces color in carrots.)

Another evolutionary enhancement to the human body might come with thicker bones, a compensatory adaptation to the fact that Mars’ gravity is only 0.38 that of Earth. A weaker gravity would cause a reduction in bone density, which Sputnik News notes would occur at 50 percent in just the first two or three years on the planet, according to endocrinologist Michael Holick. The thicker bones would give the later generations of Mars a “more robust appearance” than that of the first several generations of colonists.

Solomon also notes that there are far more factors that would impact colonists’ lives (such as the absence of Earth-like microbial life, which is ubiquitous on Earth), conditions that the colonists would have to adapt to or face death.

Solomon’s views are somewhat controversial, with scientists like Philipp Mitteröcker, a theoretical biologist at the University of Vienna, who finds it unlikely for a new human species to evolve on Mars and points out that there are human populations on Earth that have been isolated for thousands of years yet show no sign of a separate speciation.

Regardless, either view will remain moot until humanity lands and colonizes the Red Planet. In September, Space.com listed a few of the planned endeavors to get humans to Mars in the future, the article prompted by Space X’s CEO Elon Musk announcing that he was hoping to have a working colony on Mars within the next 50 to 100 years. It was noted that NASA has plans for a Mars manned space station and outpost, called Mars Base Camp, that is scheduled for 2028 (but cuts in funding to the space agency from the U.S. government cut severely extend that date into the future).

Other parties expressing interest in someday establishing a colony on Mars include the Netherlands-based nonprofit Mars One, which has plans to place a colony on the planet by 2027. There have also been plans in the works for a cooperative venture between the European Space Agency and Russia about getting humans to Mars. China has also talked about heading out to Mars, but its space program currently is centered on getting people on and into a Moon base.

[Featured Image by Algol/Shutterstock]