On Gravity and Bones: Planetary Effects upon Humans on Other Worlds

Here's a follow up to my streak of posts that bring into focus some planetary insights gained from the gaming world.

I noticed that the physique of the protagonist Marcus Fenix is burly and juggernaut-thick. The same is true for the other characters of Gears of War. The sizes of their thighs is as big as huge logs.

Now why is that so? Allow me to propose my own hypothesis. The planet they're standing on must be slightly more massive than earth. The 26-hour day of planet Sera is another clue. Sera could be a super-earth! And we all know that bigger and more massive planets exert more gravity, which means more weight bearing down on its inhabitants. And being heavier means you need bigger bones and powerful muscles to support your weight and stand upright. Thus, you need bigger limbs on Planet Sera. This could probably explain why their nemesis, the Locust Hordes (presumed to be the indigenous natives on that planet) also come with grossly huge legs and wide arms.

Of course, in this post I particularly want to highlight the fact that a creature's physique is directly influenced by its home planet’s gravity, among other things. In contrast, a planet that has a lesser surface gravity than earth might produce animals that are taller and skinnier compared to earthlings.

So, if we ever start sending humans to settle on Mars, I’m sure that the second or third generation of marsian-humans who are born there will grow to be taller and less massive than their predecessors. While the first pioneering batch would probably suffer muscle degeneration and bone loss due to the fact that the surface gravity of Mars is only 38% of Earth's gravity. You'd feel approximately three times lighter on Mars! If you were 100 lbs on earth, you'd weigh only 38 lbs on Mars. So unless earthborn human colonists strap on weights and exercise a lot to counteract the effects of Mars’ feebler gravity, humans in its present form won’t stand a chance colonizing another world.

No, don't consider that last statement as a discouragement. Consider that as an incentive and a planetary challenge for us to find new ways to be human.

Humans on other worlds.

Links:
What if Earth Were Twice as Big?
Planet Sera (on Freebase)
Planet Sera (On Gears of War Wiki)