Members of the Pontifical Swiss Guard stand by at St. Peter's Square before Pope Francis delivers his traditional Christmas Day Urbi et Orbi speech to the city and the world from the main balcony of St. Peter's Basilica at the Vatican, December 25, 2021. (Photo by Yara Nardi/Reuters)

Yoandri Hernandez Garrido, 37, proudly displays his 12 fingers in Baracoa, Guantanamo province, Cuba. His condition, known as polydactyly, is relatively common, but it's rare for extra digits to be so perfect.

Polydactyly or polydactylism (from Ancient Greek πολύς (polus) "many" + δάκτυλος (daktulos) "finger"), also known as hyperdactyly, is a congenital physical anomaly in humans, dogs, and cats having supernumerary fingers or toes. Polydactyly is the opposite of oligodactyly (fewer fingers or toes).

A fellow officer comes to the aid of injured patrolman C.V. Satt, who was pelted with rocks and beer bottles during a clash between police and relief demonstrators in Denver September 23, 1935. (Photo by Henry G. Eisenhand/AP Photo)

People in traditional costumes prepare before competing in the 55th Verdiales music contest in Malaga, southern Spain December 28, 2016. Verdiales is a form of traditional Flamenco music, which is common in the province of Malaga. Members of singing groups, known as “pandas”, wear traditional costumes decked with flowers and other accessories as they perform in the contest, which is held annually on December 28. (Photo by Jon Nazca/Reuters)

South Korean youths dance to electronic music during the Ultra Music Festival Korea at Olympic Stadium on June 10, 2016 in Seoul, South Korea. (Photo by Jean Chung/Getty Images)

Taylor Swift performs at the Billboard Music Awards. (Photo by Chris Pizzello/Invision)