This kind of thing is really interesting. I would recommend the book "Mutants", by Armand Marie Leroi for more examples.
Pharyngula has good comment on the subject:
"We have a long history in developmental biology of studying the most amazing freaks of nature — damage to developing organisms can produce astonishingly ghastly results as the embryo tries to regulate and recover, yielding results that are
almost normal. There's even a whole subdiscipline of the field, teratology, dedicated to studying aberrations of embryology. The word is perfect, since it is derived from a Greek root that means both "wonders" and "monsters"."
http://scienceblogs.com/pharyngula/2...y_horrible.php