I saw something similar to this dynamic during the Ondoy relief efforts of Tulong Bayan Operations. It was in stark contrast to how other operations work(personally I preferred the self-organizing kind than the heavily managed kind in use by most centers.)
The group started off with most people switching among the several tasks. Pretty soon it became clear that some people had comparative advantages at certain tasks (my wife at raking), while others had comparative and absolute advantages at other tasks (a burly retired ophthalmic surgeon at cutting with shears).
Productive groups generally learn quickly how to maximize output in situations like this, even with no guidance from a manager. Some people in the group (like me) were uniformly relatively good (or bad) at all tasks (had no obvious comparative advantage), so that their skills (or lack thereof) led them to spend the time alternating among all the tasks. I would think that primitive farming groups and, even further back, groups of hunters quickly learned who was relatively and absolutely good at which tasks.
via Sticking to What I’m Good At – Freakonomics Blog – NYTimes.com.