Gary K. Smith / Mistle thrush (Turdus viscivorus) feeding on Mistletoe berries (Viscum album), England, UK. March

Nick Upton / Poet's cassia / Osyris (Osyris alba) bush with red berries among coastal maquis scrubland. A plant in the mistletoe family semi-parasitic on the roots of other species, near Nafplio, Argolis, Peloponn...

Alan Williams / Mistletoe (Viscum album) growing on Apple tree (Malus domestica) in orchard Cheshire, England, UK, August.

Laurie Campbell / Mistletoe (Viscum album) close-up of berries, England, December.

Laurie Campbell / Mistletoe (Viscum album) close-up of berries, England, December.

Laurie Campbell / Mistletoe (Viscum album) close-up of berries, England, December.

Laurie Campbell / Mistletoe (Viscum album) close-up of berries, England, December.

Paul Harcourt Davies / Berries of Yellow-berried mistletoe (Loranthus europeaus). Podere Montecucco, Umbria, Italy, February.

Fabrice Cahez / European mistletoe (Viscum album) Vosges, France, December.

Fabrice Cahez / European mistletoe (Viscum album) Vosges, France, December.

Julian Hume / Illustration of extinct birds Wahi grosbeak (Chloridops wahi) (above) and the King kong finch (C. regiskongi) (below) feeding on the fruit of Sandalwood (Santalum freycinetianum) on O'ahu, Hawaii.

Michael Hutchinson / Mistletoe (Viscum alba) stem growing from Apple tree bark (Malus sp) Herefordshire, UK, May