Two ring-tailed lemurs, born in the Small Primate House, have been named Nelly and Kelly.
The male twins, who were born in November to mum, Phoebe and dad, Frank, were sexed last week.
Upper Primates Section Leader, Pat Stevens, said: “We’re really pleased with the boys’ progress.
“They’ve already started to leave mum and explore independently, so they’re coming on in leaps and bounds.”
“Phoebe is a very experienced mum, as this is her fifth litter, so she’s coping really well with two of them.”
Ring-tailed lemur babies are born after a gestation period of 132 days.