Methods | Statistics | Clinical | Educational | Industrial |
Professional items | World psychology | Vestigiality describes
homologous characters of organisms that have seemingly lost all
or most of their original function in a species through
evolution. These may take various forms such as anatomical
structures, behaviors and biochemical pathways. Some of these
disappear early in embryonic development, but others are
retained in adulthood. Although the term serves a purpose in
many gross phenotypic characteristics, vestigial has probably
little applicability to DNA sequences, be they genes or non-
coding sequences. The term junk DNA is a revealing example. It
is a value or judgmental term, which has become less utilized in
genetics, as many of the sequences once believed to be “junk”
have been discovered to have a function. Vestigial structures
are often called vestigial organs, although many of them are not
actually organs. These are typically in a degenerate, atrophied,
or rudimentary condition, and tend to