Sue Flood / Chestnut mandibled toucan (Ramphastos ambiguus swainsonii) near Boca Tapada, Costa Rica. January 2011

Diane McAllister / Swainson's Hawk juvenile (Buteo swainsonii) stretching its wings while perched on a fence in rural Palomino Valley. Nevada, USA, August

Mary McDonald / Chestnut-mandibled Toucan (Ramphastos ambiguus swainsonii) adult bird perched on the edge of the forest. Laguana del Lagarto, Costa Rica, Central America.

Neil Lucas / Chestnut mandibled toucan, Panama, Central America

Hanne & Jens Eriksen / Swainson's hawk (Buteo swainsoni) in flight. Saskatchewan, Canada, August.

Marie Lochman / Dusky antechinus (Antechinus swainsonii) Australian Alps, Kosciuszko NP, New South Wales, Australia.

Marie Lochman / Dusky antechinus (Antechinus swainsonii) Australian Alps, Kosciuszko NP, New South Wales, Australia.

Jiri Lochman / Dusky antechinus (Antechinus swainsonii) female with pouch young protruding out of the pouch, Kosciuszko NP, New South Wales, Australia.

Jiri Lochman / Dusky antechinus (Antechinus swainsonii) female with pouch young protruding out of the pouch, Kosciuszko NP, New South Wales, Australia.

Jiri Lochman / Dusky Antechinus (Antechinus swainsonii) Kosciuszko NP, New South Wales, Australia.

Jiri Lochman / Dusky antechinus (Antechinus swainsonii) female with pouch young protruding out of the pouch, Kosciuszko NP, New South Wales, Australia.

Jiri Lochman / Dusky antechinus (Antechinus swainsonii) Kosciuszko NP, New South Wales, Australia.

Heather Angel / White-collar burnet moth (Zygaena carniolica) nectaring on Catnip (Nepeta nuda). Greece. July.

Ernie Janes / Red Lupin 'My Castle' (Lupinus) with Blue Lupin 'The Governor' behind and Catmint (Nepeta) in garden. Norfolk, England, UK, May.

Ernie Janes / Red Lupin 'My Castle' (Lupinus) with Blue Lupin 'The Governor' behind and Catmint (Nepeta) in garden. Norfolk, England, UK, May.

Jane Burton / Portrait of toddler playing with black-and-white kitten using catnip mouse toy. Model released

Jane Burton / Toddler trying to get black-and-white kitten to play with a catnip mouse. Model released

Mark Taylor / Bengal x Birman cat, Spice, eating leaves from a catmint / catnip plant {Nepeta sp}

Jane Burton / Young domestic Ferret {Mustela putorius furo} playing with catnip mouse toy

Jane Burton / Domestic Cat {Felis catus} Red burmese male 'Ozymandias' luxuriating in the scent of catmint / catnip

Jane Burton / Domestic Cat {Felis catus} Tortoiseshell-and-white 'Alexandria' rubbing herself on flowering catmint / catnip

Jane Burton / Domestic Cat {Felis catus} Red burmese male 'Ozymandias' luxuriating in the scent of catmint / catnip

Jane Burton / Domestic Cat {Felis catus} cream Burmese juvenile 'Primrose' rubbing herself on flowering catmint / catnip

Stephen Downer / John Downer P / A cats' opium den - domestic cats are attracted to catnip for the volatile oils (neptalactones) the plant contains (Resolution restriction - image digitised from film, 'Weird Nature' tv series)

Phil Savoie / Garden bumblebee (Bombus hortorum) male, in flight approaching Pink catmint flower, Monmouthshire, Wales, UK.

Linda Pitkin / Cat-mint (Nepeta cataria), locally rare plant, Langley Vale Wood), Surrey, England, August. Vulnerable species in England.