Physics · Dynamics
Exaptation
A mechanism that evolved for one function is taken over for a different function in a new context
Definition
Mechanism
A trait, structure or code sequence that was selected for one purpose in one environment turns out to serve a different purpose when the environment or use changes, and is then refined for the new purpose. Feathers are thought to have evolved for temperature regulation and only later been used for flight. The original form was not built for the new target, but being already present it gives a starting point that the new target alone could not have reached step by step. It is a one-off, decisive switch of fitness target, a weak form of raising meta-accuracy, in contrast to switching back and forth between targets repeatedly.
Invariants
- The mechanism already existed before the new function used it
- The new function is different from the one the mechanism was originally selected for
- The switch of target is decisive rather than repeatedly reversed
Risks
Failure modes
Explaining a trait's origin by its current function
Treating exaptation as a rare exception rather than one sign that natural problems have several targets
Relationships
Root pattern: builds on nothing in this library.
Used by
References
Mind
Switch one line of development back and forth between two inversely related niches, so that a path to complex function exists where no path exists within a single niche
Mind
A problem in which meta-accuracy trades off against meta-precision, so that solving it requires changing shape
Reference