The medical study of teratogenesis
or grossly deformed individuals is called teratology
(the study of "monsters" or "wonders"). Monster
is a pejorative
term for a grossly deformed individual. These severely deformed humans rarely survive, although there have been some celebrated examples such as Joseph Merrick
, known as the 'Elephant Man'. Some cases, such as conjoined twins
, were formerly regarded as monsters, but are now candidates for surgery.
With greater understanding of the origins of these phenomena, this field now overlaps other fields of medicine, particularly developmental biology and embryology.