A TERRARIUM is usually a vivarium for small land animals or a sealed transparent globe for growing plants – and you’ll have to look up vivarium.

This Terrarium is much bigger, not the size of the Menwith Hill golf ball obviously, but large enough when inflated to house a very mobile man and woman (on the press night, and sometimes two men, which no doubt brings a whole new ball game to both the choreography and couture).

Courtesy of globe designers and fabricators JBL Leisure, Terrarium – Dance In A Bubble is performed by Debbi & Riccardo Meneghini or Daniel Connor & James Southward in a thick plastic, see-through orb with a zip for access, and a capacity for inflation and deflation that outdoes the Greek and Spanish governments.

The reason for this global phenomenon is the 60th anniversary of the North York Moors National Park, whose rivers, birds, landscapes, beaches, monks, insects and flowers have inspired Leeds choreographer Simon Birch, composer and soundscape designer Jon Hughes and costume designer Becs Andrews.

Hughes’s music – the outstanding feature of this new commission – is constructed from sounds recorded on the Moors, bird song, the flowing waters of the River Esk and such like, combined with cello, violin, percussion and vocal improvisations and plainchant.

A series of voiceovers also provides a poetic narrative context, complementing the extensive programme notes that explain the dancers’ progress through the moorland seasons and countryside from autumn into winter and onwards to spring and a summertime represented by the flower-power suits and waistcoats at the finale.

The dancers become more entwined, more gymnastic, more daring and physically responsive to the globe’s bouncy walls as the night progresses – and no, the bubble never bursts, only deflating around them at the exhausted finale.

Terrarium – Dance In A Bubble, Simon Birch Dance Company, Wykeham Abbey, near Scarborough, last Wednesday; now on tour until August 12. Box office: 0113 243 8765 or yorkshiredance.com