Heather Angel / Feeding trails made by snail using radula strip with rows of tiny teeth on geen algal film on glass pane. Tropical butterfly house, Kunming, Yunnan Province, China.

Ashley Cooper / Powder print from Pigeon or dove (Columba sp) flying into a house window. June 2007

Ashley Cooper / Triple glazed windows in old farmhouse refurbished to be as environmentally friendly as possible. Grayrigg, Cumbria, England, UK, April 2012.

Ashley Cooper / Triple glazed windows in old farmhouse refurbished to be as environmentally friendly as possible. Grayrigg, Cumbria, England, UK, April 2012.

Ashley Cooper / Insulation in old farmhouse refurbished to be as environmentally friendly as possible. Grayrigg, Cumbria, England, UK, April 2012.

Ashley Cooper / Greenhouses growing tomatoes heated by geothermal hot water near Husafell in Iceland. September 2010.

Franco Banfi / Commensal / Glass anemone shrimp (Periclimenes brevicarpalis) on Sea anemone, Pura Vida House Reef, Dumaguete, East Negros Island, Central Visayas, Philippines, Pacific Ocean.

Colin Monteath/ Hedgehog House / Frost patterns on glass, Ross Sea, Antarctica

Staffan Widstrand / Fence post with glass jars on fence outside house, Musteika Village, Lithuania, May 2015.

Pat Tuson / Two empty glass milk bottles on step, Holloway, London Borough of Islington England, UK

Pat Tuson / Five empty glass milk bottles on doorstep, Highbury, London Borough of Islington England UK

Pat Tuson / Five empty glass milk bottles on doorstep, Highbury, London Borough of Islington, England, UK