Sciency Words is an ongoing series here on Sci-Fi Ideas celebrating the rich and colorful world of science and science-related vocabulary. For today’s special Alien August edition of Sciency Words, we turn our attention to the term:
To rephrase a line from The Wrath of Khan: put simply, biopoiesis is life from lifelessness. Sometimes also called abiogenesis, it is a process–the details of which remain unclear–by which non-living chemicals turn into a very basic form of genetic material.
In 1871, Charles Darwin wrote a letter to his friend, J.D. Hooker, in which he speculated on the origins of life on Earth. Darwin famously described a “warm little pond” full of chemicals. Driven by heat or electricity or something, these chemicals formed proteins, which then began forming the earliest living things.
Our understanding of chemistry and biochemistry is a bit more sophisticated today than in Darwin’s time. We can fill in a few more details about this “pond.” We can say that it contained amino acids. These amino acids received energy (perhaps from sunlight, perhaps from hydrothermal vents, perhaps from lightning strikes or meteorite impacts) causing them to recombine in strange ways.
All of a sudden, the amino acids were alive! (Depending on your definition of life. Are self-replicating molecules really “alive”? I’ll leave that question to the more philosophically minded.)
But if biopoiesis is that simple, why don’t we see it occurring around us all the time? Because conditions on Earth have changed, and Earth’s current residents prevent new ones from developing. As Darwin wrote: “[…] at the present day such matter would be instantly devoured, or absorbed, which would not have been the case before living creatures were formed.”
So we can’t observe biopoiesis in progress here on Earth, and due to the shifting, sinking, and reforming of Earth’s tectonic plates, any fossilized proto-organisms that we could have examined are probably lost forever. Our only option, therefore, is to turn to the science of astrobiology.
In the last few decades, we’ve learned that organic chemicals are strewn all over the cosmos, just waiting for a jolt of energy to start biopoiesizing them. We’ve found organic material on meteorites. We’ve found it in the accretion disks around young stars. We’ve even found a cloud of organic material drifting near the super-massive black hole at the center of our galaxy.
So while we may never fully understand how life began here on Earth, there’s a good chance we’ll one day get to watch biopoiesis in action somewhere else.
Article by James Pailly. Check out James’ blog for more great science articles.