I think there must be something similar involved in migratory animals, in that the 'memory', if that is what it is, that guides them back to the various places they go to must be somehow embedded in their tissues.
Case in point is migratory eels in Sydney Australia.
The eels of Centennial Park (on the near east side of the city) may be among the city's least attractive native residents but the journey they take to breed is nothing less than astonishing.
Once in its life, every eel in Sydney gets the urge to reproduce.
When conditions are right - usually during a rainy autumn - they set off from Centennial Park and cross into Randwick Racecourse. The eels slither part of the way over land but mostly stick to stormwater drains and other water courses.
They continue south through the densely populated suburb of Kensington, across the Australian Golf Course, into the swampy Eastlakes area and across the Lakes Golf Course.
As the long-finned eels get closer to Botany Bay, their gills begin to change in preparation for saltwater and their eyes enlarge. From the golf course, they travel through swamps alongside Southern Cross Drive before entering Botany Bay at Sydney Airport's third runway.
That journey seems remarkable enough for an eel that may have spent up to 30 years (for the females) in the same sleepy pond, but it is only the prelude to a 2000-kilometre swim to New Caledonia.
The eels breed in extremely deep tropical waters in the Coral Sea, with females laying up to 20 million eggs. Perhaps unsurprisingly, the exhausted adult eels die once they have spawned their offspring.
But then another remarkable thing happens - when the eggs hatch they begin to float south on ocean currents.
They start as small gum leaf-shaped larvae, growing into see-through ''glass eels'' - a stage that protects them from predators in the sea - before becoming juvenile elvers as they reach the east coast of Australia.
Driven by instinct, the eels locate Botany Bay, swim back up through the ponds, across the golf courses, through the drainpipes, across Royal Randwick and then into Centennial Park to start a life in the shadows of the lillies.
Read more: http://www.smh.com.au/environment/conse ... z2pNs1qWgx
Personally I think there is some mechanism, not yet understood, by which memories are made available to biological organisms generally. I'm sure it is not something in the brain alone, as very simple creatures don't navigate by abstractions - they simply 'know'. The story says 'by instinct', but it's a marvellous thing, whatever it is.
He that knows it, knows it not.