This is a gynandromorph cardinal, half male and half female... a genetic abnormality that happens when the sex chromosomes (Z and W in birds) do not separate normally during early embryonic development. Credit for this find goes to Bob Motz and the photos were taken by Jim Frink. (via Kottke)Addendum: Discussion elsewhere indicates some of these bicolor cardinals may not be gynandromorphs, but rather partially leucistic birds (via i am the finch wench).
