Weekly Review

Biological Parallel

Migratory species survive extreme navigation challenges through periodic recalibration across multiple sensory systems. Bar-tailed godwits integrate magnetic, stellar, and barometric data during 11,000-km nonstop flights. Arctic terns cross-reference three independent compass systems, shifting weight between them as signals degrade. Monarch butterflies use time-compensated sun compasses that reset against the light-dark cycle. Salmon cascade from magnetic to olfactory navigation at transition points. The common architecture: no single sensor is perfect, so periodic cross-referencing catches drift before it compounds.