No, it is highly improbable that humans can evolve to not need oxygen.
The biological requirements for complex, energy-intensive organisms like humans make anaerobic existence exceptionally difficult, if not impossible, according to current scientific understanding.
Why Humans Need Oxygen
- Energy Requirements: The human body demands a significant amount of energy to maintain its complex processes.
- Anaerobic Limitations: Anaerobic respiration (without oxygen) is far less efficient than aerobic respiration (with oxygen).
- Vertebrate Constraints: The reference text explicitly states, "The larger and more complex an organism, the more energy it needs to maintain its processes. There are no entirely anaerobic vertebrates for this reason." This highlights a fundamental barrier to vertebrate life, including humans, evolving to become entirely anaerobic.
- Evolutionary Impact: Furthermore, even if humans could somehow generate sufficient energy without oxygen, their evolutionary path would have been drastically different. The reference notes, "without oxygen we wouldn't have evolved lungs and probably not a voice either, so we wouldn't look much like we do now." This emphasizes that the very physical structure of humans is intrinsically linked to an oxygen-rich environment.
The Hypothetical Human Without Oxygen
If humans somehow evolved to exist without oxygen, they would likely be vastly different from what we currently recognize as human. They wouldn't possess lungs or a voice, suggesting a completely different respiratory system and communication method. Such profound changes make the prospect of humans evolving to not need oxygen incredibly unlikely.
