We don't understand animal navigation.

This is Rupert Sheldrake's dangerous idea.

No one knows how pigeons home, or how swallow migrate, or how green turtles find Ascension Island from thousands of miles away to lay their eggs. These kinds of navigation involve more than following familiar landmarks, or orientating in a particular compass direction; they involve an ability to move towards a goal.

Why is this idea dangerous? Don't we just need a bit more time to explain navigation in terms of standard physics, genes, nerve impulses and brain chemistry? Perhaps.
But there is a dangerous possibility that animal navigation may not be explicable in terms of present-day physics. Over and above the known senses, some species of animals may have a sense of direction that depends on their being attracted towards their goals through direct field-like connections. …

The obvious way of dealing with this problem is to postulate complex interactions between known sensory modalities, with multiple back-up systems. The complex interaction theory is safe, sounds sophisticated, and is vague enough to be irrefutable. The idea of a sense of direction involving new scientific principles is dangerous, but it may be inevitable.