Evolved Exoskeletons: How Our Bodies Would Change

Imagine a world where, instead of endoskeletons, humans had evolved exoskeletons. This hypothetical reveals fascinating insights into the limitations and implications of such a biological structure.

The End of Mosquito Bites

In a world dominated by exoskeletons, life-threatening mosquito bites would become a relic of the past. Mosquitoes evolved because biting humans for blood was the most efficient way for them to obtain nutrients. With exoskeletons, our outer layers would be much harder, leaving little to no access for mosquitoes to feed. This marks a significant improvement in our quality of life, as the chances of contracting diseases like malaria and dengue fever would decrease dramatically.

Biological Limitations of Exoskeletons

The first challenge with an exoskeleton would be the prohibitive support structure. Unlike endoskeletons, which are located internally, exoskeletons are on the outside. This structural benefit is also a limitation. For instance, while insects like crabs and lobsters have smaller sizes, the principle reason is the need for a biologically expensive support system.

Adaptations to Size and Form

Adapting to exoskeletons would necessitate substantial changes in body size and shape. Most animals with exoskeletons are relatively small, and this is largely due to the limitations imposed by the exoskeleton system. The exoskeleton provides structural support but also restricts growth. As we grow larger, the muscles that support our body would need to be proportionally larger and stronger, but this is constrained by the exoskeleton's rigid nature.

There are two primary solutions to the muscle limitation problem: increasing the number of legs or reducing body weight. The former could result in a multi-legged human similar to a centipede centaur, while the latter would involve dropping down to a significantly shorter stature, like a primate. This would allow for bipedal posture and support.

Other Biological Adaptations

Beyond skeletal and muscular changes, exoskeletons would lead to other significant transformations in the body. Musculature would need to be restructured for efficient operation, leading to changes in body shape. For instance, we likely wouldn't need teeth anymore, with our mouths equipped for tearing and crushing food. Additionally, our sensory organs for touch would be altered, requiring thin-skinned sensory organs designed specifically for handling small objects.

These changes would not only affect our physical form but would also impact our way of living. Our clothing would need to adapt to work over our non-pliable, hard exoskeletons. Moreover, our senses, including touch and grip, would be significantly weaker compared to humans with endoskeletons.

Insights from Nature

To further understand the limitations and adaptations of exoskeletal structures, we can look at nature. Insects, which also have exoskeletons, face similar challenges. The size of insects is limited by the efficiency of their circulatory and respiratory systems, which do not support larger sizes as effectively. Furthermore, the entire exoskeleton of many insects is shed and replaced with each growth phase, which can leave them vulnerable to predators until their new exoskeleton hardens.

Conclusion

Evolved exoskeletons would lead to radical changes in our form, function, and way of life. While the idea is intriguing, it also highlights the intricate balance between biological structures and environmental pressures. The question of why insects are not human-sized is a testament to the constraints imposed by exoskeletal systems and the adaptations necessary for survival.