The Rule, Not the Map
Nature · · 6 min read · By No Design Editorial
A young bird raised under a false sky orients to the wrong star. What it inherits is not the constellations but a rule for reading them.
Many migrating birds hold course at night partly by the stars, and we know how in unusual detail because of a set of experiments Stephen Emlen ran in the 1960s using a planetarium.
Raise a young indigo bunting under an artificial sky that rotates around the wrong star, and it will orient to that star instead. The bird is not born knowing the constellations. It is born with a rule: find the point the sky turns around, and treat that as north. The rule then has to be calibrated against a real rotating sky during a particular window of early life.
That is a more demanding claim than the popular one, not a weaker one, because the rule and the learning period have to fit each other. An innate instruction to look for a fixed point is useless without a developmental window in which to apply it, and the window is useless without the instruction.
It is worth being straight about something else here. The popular design argument for migration leans heavily on irreducible complexity, the claim that the system fails if any part is removed. For migration that does not hold. Birds carry redundant systems, a star compass, a magnetic sense, a sun compass, landmarks, and knocking one out does not ground them. A test you only apply when it returns the answer you want is not a test.
What survives is stronger. The monarch butterfly's journey from Canada to central Mexico takes more generations than any single butterfly lives, so no individual has flown the route and returned to teach it. The insect arriving in a forest it has never seen is running a program it could not have learned from anyone who completed the trip.
'And it is He who made the stars for you, that you may be guided by them through the darkness of land and sea.' (Quran 6:97)
From Chapter 12: The Art of Migration.
Tags: Migration, Navigation, Corrections, Quran