"Where did life come from?" is such a tantalizing question, but our understanding is still tenuous, the issue controversial, and so we rarely teach it in public school biology class.
At most, they might cover Miller-Urey, which means excluding the last 70 years of discovery.
At most, they might cover Miller-Urey, which means excluding the last 70 years of discovery.
There are 3 stages we need to understand:
1. Origin of self-replicating ('autocatalytic') monomers
2. Origin of high fidelity replication
3. Encapsulation of replication systems
1. Origin of self-replicating ('autocatalytic') monomers
2. Origin of high fidelity replication
3. Encapsulation of replication systems
Synthetic biology is already yielding helpful findings.
There's a much larger 'chemical space' of nucleic acids that never arose on Earth that are capable of high fidelity replication. These can be called XNA's, xeno nucleic acids.
RNA/DNA had cousins!
nature.com/articles/s4146…
There's a much larger 'chemical space' of nucleic acids that never arose on Earth that are capable of high fidelity replication. These can be called XNA's, xeno nucleic acids.
RNA/DNA had cousins!
nature.com/articles/s4146…
I won't review details of "RNA World".
The important thing for students to know is that, while we don't know certain specifics, we've found many paths by which life could have arisen, but without evidence of early prebiotic environments, our models are based on approximation.
The important thing for students to know is that, while we don't know certain specifics, we've found many paths by which life could have arisen, but without evidence of early prebiotic environments, our models are based on approximation.
I find it enormously satisfying to know that a little thermodynamic gradient a few billion years ago, a smallish delta G, led to a self-sustaining chemical process that can visit other planets, adapt to the vacuum of space, or argue about deep-dish pizza on Twitter.
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