vestigial organ
Body's obsolete part
A vestigial organ is a body part that has lost most or all of its original function through evolution.
The human appendix, wisdom teeth, and tailbone are commonly cited examples—structures that served purposes in ancestral species but now persist in reduced or functionless form.
The wings of flightless birds are vestigial organs.
Figuratively, any remnant that has outlived its usefulness: The fax machine has become a vestigial organ of modern offices.
- appendixSupplementary section after main text
- tailboneFused vertebrae at spine's base
- wisdom teethFinal molars to erupt
- body partSection of human anatomy
- atavisticReverting to ancestral type
rudimentary · evolutionary · remnant · coccyx · useless · shrunken · dormant · ancestral · Darwin · natural selection · human evolution · regression · obsolete · functionless · trace · residual · atrophy · mutation
vestigial organvital organ
Organ necessary for life
essential organ · heart · brain · lungs · liver
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