The Zoo has been following the work of the Zoological Society of London and this evening it looks at the ground-breaking work being done at the Bedfordshire attraction involving chimps and heart surgeons.
Click above to watch ITV News Anglia's Olivia Paterson report
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A mild, windy and cloudy day with perhaps some brief breaks in the cloud. The cloud may be thick enough at times for light drizzle at times.
Mild, windy and mainly dry.
It's not Father Christmas' usual mode of transport but these young patients didn't seem to notice.