Photo taken on Aug. 24, 2019 shows meerkats at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals. (Photos: Xinhua)

Photo taken on Aug. 24, 2019 shows a white-cheeked gibbon at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.

Photo taken on Aug. 24, 2019 shows an emperor tamarin at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.

Photo taken on Aug. 24, 2019 shows an echidna at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.

Photo taken on Aug. 24, 2019 shows a mandrill at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.

Photo taken on Aug. 24, 2019 shows an Australian pelican at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.

Photo taken on Aug. 24, 2019 shows meerkats at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.

Photo taken on Aug. 24, 2019 shows a wombat at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.

Photo taken on Aug. 24, 2019 shows an echidna at the Adelaide Zoo in South Australia. Adelaide Zoo is the second oldest zoo in Australia, boasting a history of more than 130 years with more than 2,500 animals.