The Ythan estuary, 20 kilometres from Aberdeen, is one of the most inhospitable spots in the British Isles. But despite a cruel climate, the area teems with life. What could be the attraction for the hordes of eiderducks, wading birds, fish and seals that descend on this outpost? The answer lies in the shifting sands. The most detailed study of its kind ever undertaken reveals a thriving microscopic world within the tidal sands and mud. All the species here - humans included - are interlinked in a complex "web of life" maintaining nature's delicate balance.
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