Disclaimer: This a work of fiction, a mere figment of my imagination.
Abstract: Life on Mars as we know it doesn’t exist on the “surface”, but there is potential for the Martian subsurface to host a habitat for life. The information that we have gathered about the Red Planet’s subsurface right now, doesn’t tell a whole lot about whether it’s a habitable environment or not but, we have brains, so let’s imagine that the subsurface is hospitable for organisms. If it is hospitable, what would be the characteristics of the animals living there? What would they look like?
Let me give you a rough idea about them, with some illustrations.
Now, for the kind of organism I would like to present, talking about a micro-organism would be boring, so let’s say the habitat can be sustainable for a small “animal”. Speaking about how the organism would perform basic metabolic functions, etc. would require a clear understanding of the chemical nature of the Martian subsurface, because there’s a lot of science which my poor brain is incapable of grasping easily, mainly a lot of chemical equations and biochemical processes, let’s just stick to the physiological aspects of this organism as it would be easier for me to present.
The organism is subterranean, i.e. it dwells underground. Hence it is comparable to the subterranean organisms we have here on Earth. Another comparison we can make is to the Fossorial animals. A Fossorial (from Latin fossor, meaning “digger”) animal is one that is adapted to digging and lives primarily, but not solely, underground. Some examples are badgers, naked mole-rats, clams, meerkats, and mole salamanders. Using these known organisms as references, we could predict what adaptations our Martian subterranean animal would be equipped with. There are six major physical adaptations that may exist in the animal:
- Fusiform: Meaning a spindle-shaped body, tapered at both ends, adapted for the dense subsurface.
- Poor (or lack of) eyesight: Due to darkness in the subterranean environment, visual organs would be completely useless.
- Small (or missing) external ears: In order to reduce friction while burrowing it is efficient to reduce protrusions on the body.
- Short and stout limbs: Shorter limbs enable more strength output, which is important for locomotion.
- Short and broad forelimbs: Forelimbs are broad as a higher surface makes it easier to excavate. Long claws also help loosen up burrowing material for the hind limbs to disperse back.
- Short or no tail: Enables little to no locomotor activity or use to burrowing animals.
- Skeletal adjustment: The skeleton would show a triangular skull, chisel shaped teeth, prenasal ossicle (inner ear) and effectively fused or short lumbar vertebrae (segments in the backbone).
The following Illustrations would present a better understanding of the adaptations.
I present to you this skeletal diagram of how the animal would look like. From the points discussed, we would also be able to predict how the muscle groups would work. This particular “rodent” would boast exceptional neck and forelimb muscles that would enable it to provide high power output necessary for burrowing.
If we take a look at the skull, we can observe that it would be particularly streamlined. Also, take note of the huge mandibles (could be assigned to cartilage and small muscles for precise movements too).
The important part here is the auditory chamber (I made this word up). Subterranean animals usually possess sensitive auditory organs which can be modified to be sensory. These organs enable them to understand their surroundings through seismic vibrations and sounds.
Finally, the forelimb:
As the forelimb does most of the “digging” work, the tip of the phalanges is modified to be long. Also, having shorter limbs increases output power.
These predictions are in no way accurate (lol). It’s not possible to make accurate predictions without more information about the ecosystem of the animal. Knowing the ecosystem too wouldn’t be enough, as other factors like mode of nutrition, mode of reproduction, etc. would come into play. But as I said before, this is a mere figment of my imagination which I hope could spark some sort of idea or enjoyment in your head. Cheers.
Michalski, Joseph and Onstott, Tullis and Mojzsis, Stephen and Mustard, John and Chan, Queenie H. S. and Niles, Paul and Johnson, Sarah: The Martian subsurface as a potential window into the origin of life Nature Geoscience, December, 2017