Aliens could be anywhere, which is why we haven't found them.

Is it because aliens can't light fires that we haven't found them anyplace in the universe?

Researchers propose in a recent paper that life on low-oxygen exoplanets would be unable to generate combustion, a critical step in the creation of human technology.

Although fire is a natural phenomena, evidence suggests that humans first learned how to regulate it between 300,000 and 400,000 years ago. 

This eventually enabled early civilisations to process and shape metals, ushering in the Bronze and Iron Ages. 

This led in the invention of the internal combustion engine, a historical revolution.

Some claim that boiling food caused brain growth, allowing humans to continue their tremendous development.

However, laboratory experiments have revealed that oxygen levels below roughly 18% do not allow for complete burning.

This implies that even if life did thrive on such a planet, it would never be able to build advanced technology to either locate us or assist us in finding them.

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