Gorillas- the exhibit opened around 1985 I believe. First Gorillas were males Gori & Samsam and female Yinka that all came from Dublin. Female Naomi (renamed Priscilla while she was at Edinburgh) came from Bristol Zoo, giving a total of two males, two females..
Over the following years several exchanges of gorillas between Edinburgh and other zoos were made, mostly to try and promote breeding. Firstly Gori (who had become a dangerous male as he matured) was sent away(permanently) to Japan. Naomi/Priscilla was later sent to Belfast and reverted to her given name. SamSam was exchanged with male Kumba from Blackpool for a period of several years and then afterwards swapped back again. Female Yinka was exchanged with female Baffia at Chessington for one year and then they swapped again. Female Momo from Stuttgart replaced Naomi as the second female of the trio. (Samsam/Yinka/Momo)
In terms of breeding these moves were all unsuccessful though and the only successful birth was a single male baby born in 1989 to Samsam & Yinka. Named Sekondi he was handraised, mainly at Twycross. He later became the father of Matadi now in Antwerp.
When the exhibit (which was never the best for gorillas) finally closed circa 2006/7, in preparation for a revamp of the enclosure for the incoming Giant Pandas, Momo returned to Germany while Samsam and Yinka travelled to Twycross 'in transit' to a home in Spain. But Twycross' own male died soon after their move so they stayed on at Twycross permanently until their deaths.
Its hard to establish some of the exact dates- one Gorilla listings page has mistakenly omitted Edinburgh completely, and some of the individuals are quite hard to find the exact dates for too.