A pair of rare cotton-top tamarin monkeys are the newest additions at Disney’s Animal Kingdom.

Disney World shared photos of the twins, which were born at the park about a week ago. They are the first cotton-top tamarin monkeys to be born at the park since 2001, according to Disney.

At just a week old, the four-inch-long baby monkeys can be seen clinging to their mom and dad in their habitat on Discovery Island. The parents will carry the babies on their backs for as long as 14 weeks, Disney said.

Once fully grown, cotton-top tamarins will be about the size of a squirrel and weigh less than a pound.

Native to Colombia, cotton-top tamarins typically found in the tropical forests in the northwest region of the country. With fewer than 7,500 remaining in the wild, the monkeys are considered a critically endangered species. Illegal pet trade and habitat loss have contributed to their population decline.

Disney says it’s has worked with organizations like Protect Titi to help protect the species.