Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, eats a rice cake with fruit on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner 

Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, eats a rice cake with fruit on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner 

Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, eats a rice cake with fruit on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner 

Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, eats a rice cake with fruit on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner 

Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, receives a rice cake with fruit on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner TPX IMAGES OF THE DAY 

Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, eats a rice cake with fruit on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner 

Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, receives a rice cake with fruit on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner 

Western lowland gorilla Fatou, the world's oldest according to the Berlin zoo, eats a cake on her 65th birthday at the zoo in Berlin, Germany, April 13, 2022. REUTERS/Lisi Niesner 

A Western-lowland gorilla takes part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken March 11, 2021. REUTERS/John Sibley 

A Western-lowland gorilla takes part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken March 11, 2021. REUTERS/John Sibley 

Western-lowland gorillas take part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken through glass March 11, 2021. REUTERS/John Sibley 

A Western-lowland gorilla takes part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken March 11, 2021. REUTERS/John Sibley 

A Western-lowland gorilla mother Mjukuu takes part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken March 11, 2021. REUTERS/John Sibley 

A Western-lowland gorilla mother Mjukuu takes part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken March 11, 2021. REUTERS/John Sibley 

Western-lowland gorillas take part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken March 11, 2021. REUTERS/John Sibley 

Western-lowland gorillas take part in a Mother’s Day picnic provided by their keepers during a photo-call at ZSL London Zoo in London, Britain, March 11, 2021. Picture taken March 11 2021. REUTERS/John Sibley 

Richard, a western lowland gorilla, who was tested positive for COVID-19 on February 25, 2021, eats a branch inside its enclosure at closed Prague Zoo amid the coronavirus disease (COVID-19) outbreak in Prague, Czech Republic, November 10, 2020. Picture taken November 10, 2020. REUTERS/David W Cerny 

Richard, a western lowland gorilla, who was tested positive for COVID-19 on February 25, 2021, sits inside its enclosure at closed Prague Zoo amid the coronavirus disease (COVID-19) outbreak in Prague, Czech Republic, November 10, 2020. Picture taken November 10, 2020. REUTERS/David W Cerny 

Richard, a western lowland gorilla, who was tested positive for COVID-19 on February 25, 2021, sits inside its enclosure at closed Prague Zoo amid the coronavirus disease (COVID-19) outbreak in Prague, Czech Republic, November 10, 2020. Picture taken November 10, 2020. REUTERS/David W Cerny 

Richard, a western lowland gorilla, who was tested positive for COVID-19 on February 25, 2021, eats vegetables inside its enclosure at closed Prague Zoo amid the coronavirus disease (COVID-19) outbreak in Prague, Czech Republic, November 10, 2020. Picture taken November 10, 2020. REUTERS/David W Cerny 

A five-day-old baby male western lowland gorilla is fed by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. Picture taken November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is fed by his mother Buu as his father Echo embraces her at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla looks on as he is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla tries to feed from his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is raised by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is feed by his mother Buu as his father Echo touches her at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu as children watch them at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla looks on as he is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla is fed by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla sleeps on his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla looks on as he is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca 

A five-day-old baby male Western lowland gorilla looks on as he is held by his mother Buu at Bioparc Fuengirola in Fuengirola, southern Spain November 13, 2020. REUTERS/Jon Nazca TPX IMAGES OF THE DAY 

A western lowland gorilla eats vegetables at closed Prague Zoo amid coronavirus disease (COVID-19) restrictions in Prague, Czech Republic, November 10, 2020. The zoo offers meal vouchers for people to contribute to feed its animals as a part of a fundraising project during lockdown. REUTERS/David W Cerny 

A western lowland gorilla eats vegetables at closed Prague Zoo amid coronavirus disease (COVID-19) restrictions in Prague, Czech Republic, November 10, 2020. The zoo offers meal vouchers for people to contribute to feed its animals as a part of a fundraising project during lockdown. REUTERS/David W Cerny 

A western lowland gorilla nurses her young in the primate house as the National Zoo reopens for socially-distanced patrons for the first time since the start of the coronavirus disease (COVID-19) outbreak in Washington, U.S. July 24, 2020. REUTERS/Jonathan Ernst 

Thandi, a 1,5-years-old Western lowland gorilla is seen at the Antwerp zoo, in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo, in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman TPX IMAGES OF THE DAY 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman TPX IMAGES OF THE DAY 

A new born baby Western lowland gorilla is seen with its mother Mambele at the Antwerp zoo in Antwerp, Belgium June 25, 2020. REUTERS/Yves Herman 

Western lowland gorilla Fatou eats a hard-boiled Easter Egg during a media event at the Zoo in Berlin, Germany, April 16, 2019. REUTERS/Fabrizio Bensch TPX IMAGES OF THE DAY 

Western lowland gorilla Fatou eats a hard-boiled Easter Egg during a media event at the Zoo in Berlin, Germany, April 16, 2019. REUTERS/Fabrizio Bensch