Will Watson / Boulder in heathland from the Senni Formation. Mudstone layers were deposited in freshwater lakes during the Lower Devonian. Cat's Back, Black Mountains, Herefordshire, England, UK. May.

David Tipling / Pin-tailed sandgrouse (Pterocles alchata) male soaking breast feathers to carry water back to young, Belchite, Aragon, Spain, July

David Tipling / Pin-tailed sandgrouse (Pterocles alchata) two males soaking breast feathers to carry water back to young, Belchite, Aragon, Spain, July

David Kjaer / Pin-tailed sandgrouse (Pterocles alchata) male collecting water in belly/breast feathers, Spain July

Dave Watts / Common Buzzard (Buteo buteo) with white feather on breast, perched on tree branch in woodland, UK

Tui De Roy / Red-footed Booby (Sula sula) white morph represents only five percent of the Galapagos population but is reverse elsewhere, Genovesa Tower Island, Galapagos Islands, Ecuador

Doug Perrine / White tern (Gygis alba candida) pulling chick under breast to brood. Sand Island, Midway Atoll National Wildlife Refuge, Papahanaumokuakea Marine National Monument, Northwest Hawaiian Islands, USA.