1 A change of direction, usually by 180°. It commonly refers to a change of polarity of the geomagnetic field.
2 A form of homoplasy; resemblance between two taxa because one of them has gained a new character, then lost it again, and the other taxa has never gained it. Reversal by character loss is common; there is much doubt about whether it ever occurs by regaining a lost character.
Users without a subscription are not able to see the full content. Please,
or login to access all content.