In this April 4, 2017 photo, Zoologist Martha Llanes caresses baby chimpanzee Anuma II, left, while Ada hangs on to her leg, at Llanes' apartment in Havana, Cuba. She has forgiven them every transgression. It's hard to stay angry at a baby chimpanzee when it clambers up your leg and into your arms and plants a kiss on your cheek in a plea for forgiveness. (Photo by Ramon Espinosa/AP Photo)

Dog Xiaoniu dressed in clothes walks across a street with its owner (not pictured) in Shanghai, December 19, 2014. According to local media, Xiaoniu accompanies its owner to the food market everyday and is able to walk with its hind legs for up to about an hour. (Photo by Reuters/Stringer)

A competitor wearing a kilt and standing on a barrel throws a bowling ball between her legs during the “Brigaball” contest at the annual Bundanoon Highland Gathering, showcasing traditional Scottish events, held in the town of Bundanoon, located southwest of Sydney, April 9, 2016. (Photo by David Gray/Reuters)

Galagos, more commonly known as bush babies, are tiny African primates with remarkable jumping abilities. Thanks to the elastic energy stored in the tendons of their lower legs, small-eared galagos can jump 6 feet straight up in the air. (Photo by Traer Scott/Chronicle Books)

Ramela Meseljevic, a 7 year-old girl born without both of her hands and one of her legs shorter than the other, writes during classes in the her school in Begov Han, Bosnia and Herzegovina December 2, 2015. International Day of Disabled Persons is observed on December 3 with the theme "Inclusion matters: access and empowerment of people of all abilities". (Photo by Dado Ruvic/Reuters)

Meital Ben Ari, a co-founder of “Freedom Farm” pats Gary, a sheep with leg braces, at the farm which serves as a refuge for mostly disabled animals in Moshav Olesh, Israel on March 7, 2019. (Photo by Nir Elias/Reuters)

A baboon clings to the leg of an internally displaced boy at a camp on the outskirts of the town of Qol Ujeed, on the border with Ethiopia, Somaliland April 17, 2016. Across the Horn of Africa, millions have been hit by the severe El Nino-related drought. In Somaliland and its neighbouring, also semi-autonomous, Puntland region, 1.7 million people are in need of aid, according to the United Nations. In Somaliland itself, the most affected areas include the northwest Awdal region bordering Ethiopia. (Photo by Siegfried Modola/Reuters)

Sakakibara Kikai's engineer Go Sakakibara poses with the bipedal robot Mononofu during its demonstration at its factory in Shinto Village, Gunma Prefecture, Japan on April 12, 2018. Developed at Sakakibara Kikai, a maker of farming machinery, LW-Mononofu is a 28-feet tall, two-legged robot weighing in at more than 7 tonnes. It contains a cockpit with monitors and levers for the pilot to control the robot's arms and legs. (Photo by Kim Kyung-Hoon/Reuters)