Credit: Wikimedia Commons.

If Elon Musk ever has his way, humans could settle Mars as early as 2024. The goal is to move our earthling butts to another planet and finally become an interplanetary species, one less vulnerable to extinction. In the process, however, we might actually be triggering the rapid evolution of a new species that is more adapted to the alien environment — in this case, Mars. That’s what a recent study seems to hint at, listing some of the risks people trying to conceive on Mars might face and discussing some of the ethical implications that arise from it.

Would you raise your kids on Mars?

In many respects, the fourth planet from the sun is pretty Earth-like. However, while it was once home to flowing rivers and oceans of water, today the Red Planet is barren and inhospitable to life, despite our biggest hopes that one day we might find life there or at least some evidence of past life.

Both NASA and the famous SpaceX CEO Elon Musk want to establish a permanent colony on Mars at some point. This means that settlers there will also have to have babies in order to expand the colony. However, with its freezing temperature, thin atmosphere, low gravity, and a slew of other perils, Mars isn’t exactly the nicest place to raise children. Actually, according to a new study published in the journal Futures, it will be quite the ordeal.

“Reproduction on Mars will be necessary for colony survival and subsequent expansion,” the team of researchers wrote the new paper. “Unfortunately, such an endeavor comes with titanic challenges.”

The average temperature on Mars is about -80 degrees Fahrenheit (-60 degrees Celsius), although it can vary from -195 F (-125 C) near the poles during winter to as much as 70 F (20 C) at midday near the equator. The carbon-dioxide-rich atmosphere of Mars is also roughly 100 times less dense than Earth’s on average, but it is nevertheless thick enough to support weather, clouds, and winds. A thin atmosphere means much more radiation from the sun reaches Mars’ surface than on Earth. This increases the risk of developing brain cell damage and various cancers. And concerning reproduction, it will also severely impact sperm count. Some of these radiation effects may be offset if the colony is located deep under the Martian surface — but it’s unclear at this point how safe humans would be in such conditions.

Mars also has a much weaker gravity than on Earth, about a third of we’re used to. This means that there’s far less pressure and stress on the human body, which sounds like good news. The problem is that this sudden change in gravity will impact human health, as previous studies on astronauts stationed to the ISS have shown. Altered vision and increased pressure inside the head are among the physiological changes both men and women experience following space flight. These symptoms have been lumped together by NASA under the ‘visual impairment intracranial pressure syndrome’, or VIIP syndrome for short. Scientists hypothesized that at least one of the causes for VIIP syndrome could be related to the redistribution of body fluid toward the head due to microgravity exposure.

Microgravity also seems to change the brain structure of astronauts. Although Mars has some gravity, it’s conceivable that it could have similar effects on colonists’ health — albeit to a less degree than on the ISS — since it’s much lower than Earth’s. What’s more, babies born on Mars would face huge problems adjusting to Earth, if they ever decide to travel there. For example, one NASA scientist, Al Globus, gives an example of someone who weighs 160 pounds. “If I went to a 3g planet, the equivalent of moving from Mars to Earth, I would weigh almost 500 pounds and would have great difficulty getting out of bed,” Globus told Live Science in 2011.

Some might interject that many of these issues can be solved with technology: We can build better shelters and, at the end of the day, Martian settlers will just have to alter their babies’ genome in order for them to adapt to alien conditions. But this would entail a set of ethical and social challenges the likes of which humans have never before experienced. It could mean that some people would simply not be allowed to have kids, for instance. Also, in a very resource-limited Martian society, very weak or ‘useless’ individuals might have to be discarded for the greater good of the colony.

“The idea to protect life at every stage of development may not be suited to a Mars colony,” the authors wrote. “An inhospitable environment and a small mission crew may result in the elevation of the value of group over the individual.”

“The method of CRISPR makes possible adaptive genetic engineering,” the authors wrote. “We should consider the idea of genetic human enhancement before and during that mission.”

In doing so, however, we might end up creating a new species of humans.

For centuries, ever since the first astronomers turned the first rudimentary telescopes towards Mars, mankind has imagined encountering Martians. Ironically, these fabled Martians might just end up being a new race of Earthlings.