Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus), three climbing tree. Northern Colombia.

Floris van Breugel / Young California fan palm (Washingtonia filifera) in sunshine among older palms in a remote oasis in Anza-Borrego Desert State Park, California, USA March

Bernard Castelein / Common cotton grass (Eriophorum angustifolium) Klein Schietveld, Brasschaat, Belgium, May.

Lisa Hoffner / Wild Cotton-top tamarins (Saguinus oedipus) climbing up fallen branches in dry tropical forest of Colombia, South America. IUCN List: Critically Endangered

Thomas Marent / Cotton-top Tamarin (Saguinus oedipus) in tree, northern Colombia

Claus Meyer / Cotton-top Tamarin (Saguinus oedipus), Colombia

Lucas Bustamante / Ceiba or Kapok (Ceiba pentandra) tree in the Amazon Basin. Yasuni National Park, Orellana, Ecuador

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus), two in tree. Northern Colombia.

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus) sitting in tree, looking at camera. Northern Colombia.

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus), two sitting in tree, looking downwards. Northern Colombia.

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus) looking at camera whilst holding on to tree trunk. Northern Colombia.

Suzi Eszterhas / Cotton-top tamarin (Saguinus oedipus) resting on branch. Northern Colombia.

Hanne & Jens Eriksen / Arabian gazelle {Gazella gazella} and Chestnut-bellied sandgrouse {Pterocles exustus} drinking from pool of water, Oman

Hanne & Jens Eriksen / Chestnut bellied sandgrouse male drinking {Pterocles exustus} Jaaluni, Oman

Hanne & Jens Eriksen / Chestnut bellied sandgrouse {Pterocles exustus} male, collecting water in feathers, Jaaluni, Oman

Melvin Grey / Chestnut-bellied sandgrouse (Pterocles exustus olivascens) male. Ndutu, Tanzania.

Melvin Grey / Chestnut-bellied sandgrouse (Pterocles exustus olivascens) pair in flight. Meru National Park, Kenya.

Melvin Grey / Chestnut-bellied sandgrouse (Pterocles exustus olivascens) male soaking feathers to provide chicks at nest with water. Meru National Park, Kenya.

Hanne & Jens Eriksen / Chestnut bellied sandgrouse (Pterocles exustus) flock in flight, Oman, February

Hanne & Jens Eriksen / Chestnut bellied sandgrouse (Pterocles exustus) juvenile feeding, Oman, May

Christine Jung / Chestnut-bellied Sandgrouse (Pterocles exustus), Mirbat, Oman

Thomas Rabeil / Chestnut Bellied Sandgrouse (Pterocles exustus) on sandy ground at seasonal waterhole. Dilia Achetinamou, Termit Tin Toumma National Park, Sahelo-Saharan Biome, Niger.

Thomas Rabeil / Group of Chestnut Bellied Sandgrouse (Pterocles exustus) in flight at seasonal waterhole. Dilia Achetinamou, Termit Tin Toumma National Park, Sahelo-Saharan Biome, Niger.

Thomas Rabeil / Chestnut Bellied Sandgrouse (Pterocles exustus) standing on sand. Dilia Achetinamou, Niger, Africa.