sentence: Migratory animals know their locations by the intensity of the field.
sentences_before: Animals that undergo long migrations depend on the magnetic field for a guide. The magnetic field is used for many things in these migratory animals.
sentences_after: They know the time because of circadian rhythms the field produces. Migratory animals are born with a magnetic map in their head that allows them to migrate great distances safely. Their ability to sense the magnetic field is because of magnetic particles. Other animals have a chemical compass based on a radical pair mechanism.
concept_name: migratory animal
headings: Earth's magnetic field Migratory Animals
categories: Earth Magnetism