Two new golden lion tamarin monkeys have been born at the Cleveland Metroparks Zoo, the second and third to be born in the past year to their parents.

Golden lion tamarins (Leontopithecus rosalia), considered one of the most endangered mammals on Earth, are bright orange-colored monkeys that live in small family groups. The large amount of hair around the face resembles a lion's mane, earning the species its name. Golden lion tamarins are born weighing around 2 ounces (56 grams), with their eyes open and all of their hair. Adults on the other hand, typically weigh 22 to 25 ounces (623 to 708 grams) and grow between 13 and 16 inches (33 to 41 centimeters) long. [See some other cute baby animals.]

The two newest tamarin additions were born on Dec. 27 to Brie and Cumin, who gave birth to big brother Orolito 10 months ago. The sexes of the newest additions to the family have yet to be determined (the sex of monkeys cannot be verified immediately after birth).

Golden lion tamarins live in small family groups and all members of the group, including the adult males and adolescents, cooperate in raising the young.

Golden lion tamarins are one of the most endangered mammals on earth. (Image credit: Cleveland Metroparks Zoo)"We're very happy with these infants as it not only helps grow the population, but it also allows Orolito to learn valuable parenting skills while he helps with the rearing of these two baby tamarins," said Chris Kuhar, the zoo's curator of primates and small mammals. "We hope to continue the success we've had with this species in the future."

Sadly, deforestation and habitat loss have forced the entire population of golden lion tamarins into a small region in eastern Brazil. Consequently, almost all golden lion tamarins found in U.S. zoos are considered to be on loan from the Brazilian government.

In an attempt to save the golden lion tamarins, the species has been made part of a Species Survival Plan (SSP) organized by the Association of Zoos & Aquariums. Through the SSPs, zoos and institutions collaborate to manage the population of endangered species. Since 1997, The Cleveland Metroparks Zoo has contributed 19 golden lion tamarin births to the SSP.

"Cleveland Metroparks Zoo continues to support the population management goals and conservation work of the golden lion tamarin SSP," Kuhar said.

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