According to a new one study published in the journal Nature Astronomy, some alien civilizations may be intelligent but face limitations in technological development due to the characteristics of their atmosphere.
One of the most important factors identified in the study is the oxygen level in the atmosphere. Oxygen plays an important role in the evolution of life, and researchers suggest that its availability may be critical to the development of technologically advanced species.
The article emphasizes that, apart from the need for respiration and metabolism in multicellular organisms, oxygen is crucial for the development of fire – and fire is a hallmark of a technological civilization. However, if the planet lacks sufficient oxygen levels, this could prevent the fires necessary for technological development.
“On Earth, fire certainly played a crucial role in the rise of human civilization and the rise of technology,” the study explains.
Cooking was important for our development, it gave us more energy and possibly helped increase the size of our brains. Fire has also been used by humans to control the environment and aid us in hunting.
“By far the most important role of fire in the rise of human civilization, however, is its use as an energy source,” the article says.
“It probably started as a way to retain heat, expanding the range of environmental conditions suitable for settlements. This then evolved into more complex applications such as metal smelting and tool making. Finally, it provided the energy source and fuel that ushered in the Industrial Revolution and led to the Anthropocene.”
The article calls this phenomenon an “oxygen bottleneck” and suggests that oxygen-starved alien species, while intelligent, will remain technologically untapped. The authors of the article suggest that the lack of oxygen may isolate these creatures, limiting their development.
An oxygen bottleneck could prevent intelligent, tool-using, and possibly communicative species from evolving into technologically advanced species capable of contacting us, perhaps explaining the lack of contact.
The team suggests other possible ways that primitive species could produce heat, such as focusing the rays from their stars or geothermal energy, but none are as simple or readily available as combustion.
Co-author Adam Frank hypothesizes that intelligent beings on planets with low oxygen levels would not be able to use fire to cook food, control the environment or create complex technologies.
Experts urge caution when interpreting potential technical signals from planets where oxygen levels are insufficient. This could be an important factor in weeding out unsuitable objects in the search for intelligent life in space.
