It may finally have been revealed why Adelaide's giant pandas Wang Wang and Funi have failed to produce offspring - they just don't fancy each other.
New research has found the reproductive rates of giant pandas living in zoos are substantially increased when they show a liking for one another.
The study in Nature Communications says breeding programs could be improved if pandas are allowed to choose their own mates.
Study author Meghan Martin-Whintle and her colleagues studied 40 pandas at a conservation and research centre in China that were allowed to freely choose between two potential partners.
Individual pandas were placed in the centre of an enclosure and given visual access to potential mates.
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The study revealed both mating success and cub production were significantly enhanced when a panda showed a strong preference for a particular partner and were enhanced even more if both pandas shared a liking for each other.
"Incorporating mating preference trials into captive panda breeding programs could therefore prove to be a cost-effective and efficient way to ensure the continued survival of pandas," the study said.
Wang Wang and Funi were brought together in Adelaide in 2009, on loan from China for a decade, with the aim of producing panda babies.
But so far there's been no pitter patter of little panda feet, with the lack of success usually blamed on the extremely short fertility window which lasts just 48 hours.
Earlier this year the sensitive subject of just when a baby could be expected was raised in federal parliament in a question from LNP Senator James McGrath.
"It is a very personal question - it's not something I'm inclined to ask a panda about," the environment department's Stephen Oxley replied.
Perhaps the question Senator McGrath should have asked is did anyone check if Wang Wang and Funi actually like each other.
