Evolution Quote by Lee Spetner
““A mutation that reverses the effect of a previous one (called a back mutation) could at one stroke revive a complex function that had been earlier shut off. If you didn’t know it was a back mutation you might be tempted to think it added a lot of information to the genome. But once you know that a single mutation cannot add more than one bit of information, you know that the complexity must have already been in the genome. The mutation must have turned ‘ON’ what had been an existing, but dormant, system.””
About This Quote
Source Paper: Evolutionary Genetics, Lee Spetner, 1995
A back mutation can reactivate a previously dormant complex function, showing that the genetic information was already present.
In simple terms: A single mutation can’t add new information, only turn existing systems on.
Key Takeaway
Recognize that complexity may be hidden, not newly created.
Themes
evolution
genetics
information theory
Mood
analytical
curious
Type
scientific
educational
When to use this quote
- genetic research
- medical genetics
- synthetic biology
- evolutionary studies
Key Concepts
back mutation
genomic complexity
latent systems
Questions to Reflect On
- What hidden capacities might genomes possess?
- How does this view affect interpretations of evolutionary innovation?
A Different Perspective
If multiple mutations interact, the simple bit‑limit may not hold.
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