In the latest iOS update, Apple added room for the fifth digit.
The fifth digit actually had two additional joints and became somewhat opposable to the rest of the hand.
The fifth digit doesn't do much of anything anyway, so what would you lose if you didn't have one?
Anatomically, it consists of the distal manual phalanx of the fifth digit or, in layman's parlance, the tip of the little finger.
Study Design: Nuchal thickness, humerus and femur lengths, hyperechoic bowel, hypoplastic fifth digit (clinodactyly), and any gross anatomic defects were measured or ascertained in singleton pregnancies that were undergoing genetic amniocentesis.
Suppression of digits in hoofed mammals frequently has occurred in the following sequence: the pollex (first digit) is the first to be suppressed, then the minimus (fifth digit), the index (second digit), and finally the annularis (fourth digit).
The loss of the first toe on the front foot led to the four-toed condition common in the Eocene; the fifth digit persisted, although it was somewhat weak.
The fifth digit of the hindfoot was the next to disappear in the evolutionary sequence, and all known forms beyond the lower Oligocene had only three toes in each foot.
Actually, we know from other specimens of Dilophosaurus that it had a fourth and fifth digit on each pes, but these are extremely reduced, and were not preserved in the holotype specimen.
In 2008, the distal manual phalanx of the fifth digit of a hominin was excavated in Denisova Cave (51°40′ N; 84°68′ E) in the Altai Mountains, Russia.
