A protester takes part in a demonstration as part of the Fridays for Future movement amid the ongoing climate crisis in Milan, Italy on October 6, 2023. (Photo by Claudio Furlan/LaPresse/Rex Features/Shutterstock)

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)

Singer Rihanna performs onstage during the 2011 Billboard Music Awards at the MGM Grand Garden Arena May 22, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images for ABC)

Members of the Cyclophonica band play instruments as they make a stop during a ride in Rio de Janeiro May 17, 2015. The Cyclophonica band was formed by a group of musicians riding bicycles around the city, mixing sport and culture and entertaining people on the streets, according to its founder Leonardo Fuks. (Photo by Pilar Olivares/Reuters)

Singers Steven Tyler (L) and Nicole Scherzinger perform onstage at the iHeartRadio Music Festival held at the MGM Grand Garden Arena on September 24, 2011 in Las Vegas, Nevada. (Photo by Ethan Miller/Getty Images for Clear Channel)