What does “life” mean to you? As we previously explored on Lurking Beyond, alien life might not look like anything we can recognize. Rather than the humanoid aliens offered by popular sci-fi imaginings, alien life could be deeply strange and unfamiliar.
Researchers Stuart Bartlett and Michael L. Wong published a paper in April of this year to redefine “lyfe” as we know it.
“Lyfe is defined as any system that fulfills all four processes of the living state, namely: dissipation, autocatalysis, homeostasis, and learning,” they write in their paper.
“We contend that most standard definitions of life are restrictive and may blind future astrobiological research from life that is hiding in plain sight,” the authors argue. They take particular offense with NASA’s current definition of life, which is “a self-sustaining chemical system capable of Darwinian evolution.”
Honestly, that’s my new Tinder bio. But NASA’s definition is too narrow and Earth-centric for these scientific mavericks.
What do the four pillars of “lyfe” represent? Essentially, the researchers have created a series of questions that can be applied to any kind of system, no matter its size or location, to determine if it’s “alyve.”
Dissipation: Can the system exchange one type of energy for another? A simple example is a plant that converts radiant energy from the sun into food through photosynthesis?
Autocatalysis: Will the system continue to reproduce exponentially under ideal conditions? Think of a colony of yeast continuing to grow until it eats up all the sugar available in a piece of bread dough.
Homeostasis: Can the system maintain a relatively stable existence within certain parameters? Even though outward temperatures might vary wildly, humans maintain consistent body temperature.
Learning: We can understand this one pretty easy, right? The authors define “learning” as a system’s ability to store and process information.
In a recent paper in the Proceeding of the National Academy of Sciences of the Untied States of America, Sid Perkins posits that life (or “lyfe”) is most likely to be found in ancient lava tubes.
“If Mars ever hosted life, it may have moved into such refugia as the planet evolved and surface conditions became increasingly harsh. Indeed, some researchers suggest that microbial life may yet hang on in the Red Planet’s underground havens,” Perkins writes.
Lava tubes can burrow down deep into the crust of a planet, chewing up rock or ice to drop hundreds and hundreds of meters. Astronomers have spotted partially collapsed lava tubes on the moon, which used to have strong volcanic activity. Perkins believes that these might provide future habitats for human colonists, safe from the harsh surface conditions. And it’s possible that the lava tubes provided similar shelter for ancient alien races.
If that life does exist, perhaps flourishing in such extreme conditions, it isn’t likely to look like the life that evolved on Earth. Just as deep-sea life appears strange to us, so too may alien life. Maybe lyfe will indeed catch on and completely change the conversation about alien existence. Because according to Bartlett and Wong, the real challenge is not finding lyfe in the universe, but recognizing it when we do.