Bernard Castelein / Coquerel's sifaka (Propithecus coquereli) in tree, relaxing, Ankarafantsika National Park, Madagascar

Bernard Castelein / Silky sifaka (Propithecus candidus) in tree, Marojejy National Park, Madagascar. Critically endagered species.

Houdin and Palanque / Decken's sifaka (Propithecus deckenii) grooming each other, Tsimembo area, Madagascar. Lenses for Conservation project.

Houdin and Palanque / Decken's sifaka (Propithecus deckenii) female and her young playing, Tsimembo area, Madagascar. Lenses for Conservation project.

Houdin and Palanque / Decken's sifaka (Propithecus deckenii) female and her young playing, Tsimembo area, Madagascar. Lenses for Conservation project.

Houdin and Palanque / Decken's sifaka (Propithecus deckenii) Tsimembo area, Madagascar. Lenses for Conservation project.

Houdin and Palanque / Decken's sifaka (Propithecus deckenii) grooming each other, Tsimembo area, Madagascar. Lenses for Conservation project.

Lorraine Bennery / Sifaka de Decken (Propithecus deckenii), sitting in tree, Tsingy de Bemaraha National Park, Madagascar, Endangered, endemic.

David Pattyn / Diademed sifaka (Propithecus diadema diadema) pair, Maromizaha Reserve, Andasibe Mantadia area, eastern Madagascar. August.

Cyril Ruoso / Verreaux's sifakas (Propithecus verreauxi) in Madagascar ocotillo (Alluaudia procera) trees Berenty, Madagascar.

Cyril Ruoso / Verreaux's sifaka (Propithecus verreauxi) two resting Berenty, Madagascar.

Nick Garbutt / Adult male Diademed Sifaka (Propithecus diadema) 'skipping / dancing' across open ground between forest fragments, eastern Madagascar.

Nick Garbutt / Infant Golden-crowned Sifaka (Propithecus tattersalli) on its mother's back. Forests adjacent to the village of Andranotsimaty, near Daraina, northern Madagascar. Critically endangered species.

Nick Garbutt / Golden-crowned Sifaka (Propithecus tattersalli) leaping through forest canopy. Forests adjacent to the village of Andranotsimaty, near Daraina, northern Madagascar. Critically endangered species.

Andy Rouse / Coquerel's Sifaka (Propithecus coquereli) jumping, Palmarium Reserve, Madagascar

Andy Rouse / Coquerel's Sifaka (Propithecus coquereli) jumping, Palmarium Reserve, Madagascar

Andy Rouse / Coquerel's Sifaka (Propithecus coquereli) climbing tree, Palmarium Reserve, Madagascar

Andy Rouse / Coquerel's Sifaka (Propithecus coquereli) jumping, Palmarium Reserve, Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) mother carrying baby. Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) mother carrying baby. Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) mother carrying baby. Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) jumping ('dancing') across ground, Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) portrait, Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) jumping ('dancing') across ground, Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) jumping ('dancing') across ground, Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) jumping across ground with baby on its back, Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) jumping across ground with baby on its back, Madagascar

Andy Rouse / Verreaux Sifaka (Propithecus verreauxi) in forest, Madagascar

Andy Rouse / Verreaux Sifakas (Propithecus verreauxi) jumping ('dancing') across ground, Madagascar

Andy Rouse / Coquerel's Sifakas (Propithecus coquereli) in coastal rainforest, Palmarium Reserve, Madagascar

Nick Garbutt / Golden-crowned Sifaka or Tattersall's Sifaka (Propithecus tattersalli) in forest near Andranotsimaty, Daraina, north east Madagascar. Critically Endangered.

Nick Garbutt / Milne-edward's sifaka lemur (Propithecus diadema edwardsi) infant head portrait, Ranomafana National Park, south east Madagascar.

Nick Garbutt / Verreaux's sifaka lemur (Propithecus verreauxi) hanging in relaxed posture from a branch in the canopy, Berenty Private Reserve, southern Madagascar.

Nick Garbutt / RF- Verreaux's sifaka lemur (Propithecus verreauxi) hanging from branch while feeding in canopy. Berenty Private Reserve, southern Madagascar. Endangered species. (This image may be licensed either a...

Inaki Relanzon / Silky sifaka (Propithecus candidus) adult with juvenile in tree, Marojejy National Park, North Madagascar Critically endangered, November 2010

Inaki Relanzon / Milne-Edwards' sifaka (Propithecus edwardsi) with young on its back, Ranomafana National Park, Madagascar, Endangered, September

Alex Hyde / Diademed Sifakas (Propithecus diadema diadema) family group with baby in tropical rainforest. Andasibe-Mantadia National Park, Eastern Madagascar. IUCN Endangered Species.

Alex Hyde / Diademed Sifakas (Propithecus diadema diadema) family group with baby in tropical rainforest. Andasibe-Mantadia National Park, Eastern Madagascar. IUCN Endangered Species.

Andy Rouse / Verreaux's sifaka (Propithecus verreauxi) running carrying baby, Berenty Private Reserve, Madagascar

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October

Anup Shah / Verreaux's sifaka (Propithecus verreauxi) mother carrying baby 'hopping' across open ground to reach new feeding area, Berenty Private Reserve, Madagascar, October