Name: Sun bear (Helarctos malayanus)

Where it lives: Southeast Asia

What it eats: Ants, bees, beetles, honey, termites, fruit, plants, small mammals and birds

Why it’s awesome: Sun bears often stand on their hind legs and can look so similar to humans they’ve been mistaken for people wearing costumes.

Sun bears are the smallest bears in the world. While grizzly bears (Ursus arctos horribilis) can weigh more than 700 pounds (320 kilograms), sun bears weigh between 60 and 150 pounds (30 to 70 kg) and are between 4 and 5 feet (1.2 to 1.5 meters) long.

Related: Qinling panda: The shrunken pandas that diverged 300,000 years ago and sometimes come out brown

Found in Malaysia, China, Thailand, Laos, Cambodia, India, Bangladesh and Myanmar, sun bears take their name from the golden or white patch on their chests, which resembles the rising sun. Although they’ve been nicknamed “dog bears” because of their stocky build and short muzzles, these tree-dwelling mammals are best known for their human-like behavior. They often stand on their hind legs and have even been seen waving.

In the wild, standing frees up their front paws so they can reach for food such as fruit and dig into beehives and termite nests for honey and insects. They also have a 12-inch (30 centimeters) tongue to help them get their food — the longest tongue of any bear.

Sun bears also stand to check out their surroundings and to scare away other animals such as tigers, as it enables them to display their colorful chest patch as a warning sign. Standing upright also helps them to smell over longer distances.

Female sun bears have even been spotted walking around on their hind legs while carrying their babies in their arms. This may help mother bears, called sows, to spot predators and safely move their offspring around.

Recently, a captive sun bear named Angela became an internet sensation after she stood up and waved to visitors at Hangzhou Zoo in China. Her build, posture and behavior seemed so human that people thought she was a performer in costume.

Exactly why these bears appear to wave is unknown, but it could be to communicate.

A study published in the journal Nature in 2019 found that captive sun bears are excellent communicators and can mimic each other’s facial expressions to build bonds — a behavior that humans do too. Biologists at Arizona State University and the University of Arizona suggest sun bears have evolved to be skilled tree climbers and because of this dexterity, may wave simply because they can.

Sun bears are classified as vulnerable on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species because of habitat loss and hunting. They are poached for bile from their gall bladders, which is used in traditional medicine, and for their paws, which are eaten.