Paul Williams / Red leaf monkey (Presbytis rubicunda) mother holding baby, Danum Valley, Sabah, Borneo, Malaysia August.

Michael D. Kern / Maroon eye / Moon frog (Leptopelis uluguruensis) captive, from East Africa

Tim Fitzharris / Quaking Aspen (Populus tremuloides) grove in fall colors, Maroon Bells, Snowmass Wilderness, Colorado

Pete Oxford / Maroon eyed leaf frogs {Agalychnis litodryas} Esmeraldas, Ecuador

Oscar Dewhurst / Long-billed sunbird (Cinnyris lotenius) nectaring on flowers. Goa, India. September.

Sergio Hanquet / Purple sea urchin (Sphaerechinus granularis). Tenerife, Canary Islands.

Nick Garbutt / Orange backed red langur (Presbytis rubicunda chrysea) in rainforest understorey. Danum Valley, Sabah, Borneo, Malaysia.

Heather Angel / Broomrape (Pedicularis longiflora) in wet meadow amongst Horsetail (Equisetum sp). Maroon marks on flowers act as Nectar guides. Road from Barkham to Ruo Er Gai, Sichuan Province, China. July.

Gary Bell/ Oceanwide / Spine-cheek Anemonefish (Premnas biaculeatus) juvenile in sea anemone, Great Barrier Reef, Australia

Chase Dekker / Mountains reflected in lake, Maroon Bells, Aspen, Colorado

Bert Willaert / Spinecheek anemonefish (Premnas biaculeatus) living in a symbiotic relationship with Bubble-tip anemone (Entacmaea quadricolor). Kimbe Bay, West New Britain, Papua New Guinea

Constantinos Petrinos / Juvenile spine-cheek anemonefish (Premnas biaculeatus) in its host Bubble-tip Anemone (Entacmaea quadricolor) Lembeh Strait, North Sulawesi, Indonesia.

Constantinos Petrinos / Juvenile spine-cheek anemonefish (Premnas biaculeatus) in its host Bubble-tip Anemone (Entacmaea quadricolor) Lembeh Strait, North Sulawesi, Indonesia.

Constantinos Petrinos / Juvenile spine-cheek anemonefish (Premnas biaculeatus) in its host Bubble-tip Anemone (Entacmaea quadricolor) Lembeh Strait, North Sulawesi, Indonesia.

Constantinos Petrinos / Juvenile spine-cheek anemonefish (Premnas biaculeatus) in its host Bubble-tip Anemone (Entacmaea quadricolor) Lembeh Strait, North Sulawesi, Indonesia.

Christophe Courteau / Red leaf monkeys (Presbytis rubicunda) feeding in the canopy, Danum Valley Conservation Area, Sabah, Borneo, Malaysia.

Tim Laman / Red leaf monkey (Presbytis rubicunda) in strangler fig tree (Ficus dubia) Gunung Palung National Park, Borneo

Tim Laman / Red leaf monkey (Presbytis rubicunda) female with baby in strangler fig tree (Ficus dubia) Gunung Palung National Park, Borneo

Tim Laman / Red leaf monkey (Presbytis rubicunda) female eating fruit in strangler fig tree (Ficus dubia) Gunung Palung National Park, Borneo

Tim Laman / Red leaf monkey (Presbytis rubicunda) female eating fruit in strangler fig tree (Ficus dubia) Gunung Palung National Park, Borneo

Tim Laman / Red leaf monkey (Presbytis rubicunda) in strangler fig tree (Ficus dubia) Gunung Palung National Park, Borneo

Tim Laman / Red leaf monkey (Presbytis rubicunda) with baby, in strangler fig tree (Ficus dubia), Gunung Palung National Park, Borneo.

Tim Laman / Red Leaf Monkey (Presbytis rubicunda) in Strangler fig tree (Ficus dubia) eating a fig. Gunung Palung National Park, Borneo.

Tim Laman / Red leaf monkey (Presbytis rubicunda) female feeding in Strangler fig tree (Ficus dubia) Gunung Palung National Park, Kalimantan, Borneo, Indonesia.

Tim Laman / Red leaf monkey (Presbytis rubicunda) female feeding on fig, in Strangler fig tree (Ficus dubia) Gunung Palung National Park, Borneo.

Tim Laman / Red leafmonkey (Presbytis rubicunda) female in Strangler fig tree (Ficus dubia), Gunung Palung National Park, Borneo.

Linda Pitkin / Spine-cheek anemonefish (Premnas biaculeatus) in host Bulb-tentacle sea anemone (Entacmaea quadricolor) Lembeh Strait, North Sulawesi, Indonesia, February 2016

Glenn Bartley/ BIA / Maroon-bellied Parakeet (Pyrrhura frontalis), Atlantic Rainforest, Brazil

Melvin Grey / Silver-beaked tanager (Ramphocelus carbo magnirostris) adult male, Asa Wright, Trinidad

Tim Fitzharris / Maroon Bells, Maroon Lake, Colorado

Tim Fitzharris / Mountains in autumn, Elk Mountains and Maroon Bells, Maroon Bells-Snowmass Wilderness Area, Colorado

Christophe Courteau / Maroon / Red leaf monkey / Langur (Presbytis rubicunda) eating fruits in tree, Danum Valley Conservation Area, Sabah, Borneo, Malaysia.

Christophe Courteau / Maroon / Red leaf monkey / Langur (Presbytis rubicunda) eating fruits in tree, Danum Valley Conservation Area, Sabah, Borneo, Malaysia.

Murray Cooper / Maroon-tailed Parakeet (Pyrrhura melanura) trio taking flight, Ecuador

Nick Garbutt / Maroon langur (Presbytis rubicunda) in rainforest canopy. Danum Valley, Sabah, Borneo.

Nick Garbutt / Maroon langur (Presbytis rubicunda) in rainforest canopy. Danum Valley, Sabah, Borneo.

Nick Garbutt / Maroon langur (Presbytis rubicunda) in rainforest canopy. Danum Valley, Sabah, Borneo.

Nick Garbutt / Maroon langur (Presbytis rubicunda) in rainforest canopy. Danum Valley, Sabah, Borneo.

Pete Oxford / Maroon-tailed Parakeet (Pyrrhura melanura) feeding on fruit, Mashpi Rainforest Biodiversity Reserve, Pichincha, Ecuador

Georgette Douwma / Spinecheek anemonefish (Premnas biaculeatus) male with bleached anemone, Bunaken National Park, North Sulawesi, Indonesia

Alex Mustard / Spinecheek anemonefish (Premnas biaculeatus) pair in their host anemone on a coral reef. The larger fish is the female. Fiabacet Island, Misool, Raja Ampat, West Papua, Indonesia. Ceram Sea.

Adrian Davies / Red Leaf monkey (Presbytis rubicunda) feeding on fruit, Sabah, Borneo.

Pascal Kobeh / Juvenile spine-cheek anemonefish (Premnas biaculeatus) in a bleached bulb-tentacle sea anemone (Entacmaea quadricolor) Bismark Sea, Papua New Guinea.

Thomas Marent / Red Leaf Monkey (Presbytis rubicunda) feeding on leaves, Tawau Hills Park, Sabah, Borneo, Malaysia

Dong Lei / Maroon Oriole (Oriolus traillii traillii) male perched on branch in tropical forest, Xishuangbanna National Nature Reserve, Yunnan Province, China. March.

Paul Williams / Red leaf monkey (Presbytis rubicunda) mother and baby, Danum Valley, Sabah, Borneo, Malaysia August.

Paul Williams / Red leaf monkey (Presbytis rubicunda) mother and baby, Danum Valley, Sabah, Borneo, Malaysia August.

Alex Hyde / Maroon langur / Red leaf monkey (Presbytis rubicunda) Danum Valley, Sabah, Borneo.

Luiz Claudio Marigo / Maroon-bellied parakeet (Pyrrhura frontalis) perched on branch, Serra Bonita Private Natural Heritage Reserve (RPPN Serra Bonita), Camacan, Southern Bahia State, Eastern Brazil.

Luiz Claudio Marigo / Maroon-bellied parakeet (Pyrrhura frontalis) perched on branch, Serra Bonita Private Natural Heritage Reserve (RPPN Serra Bonita), Camacan, Southern Bahia State, Eastern Brazil.

Luiz Claudio Marigo / Silver-beaked tanager (Ramphocelus carbo) Pantanal, Brazil.

Robin Chittenden / Silver-beaked tanager (Ramphocelus carbo) perched, Trinidad and Tobago.

Chien Lee / Red Leaf Monkey (Presbytis rubicunda)and young, Danum Valley Field Centre, Borneo, Malaysia

Chien Lee / Red Leaf Monkey (Presbytis rubicunda), Danum Valley Field Centre, Borneo, Malaysia

Bernard Castelein / Monks leaving the gompa after a prayer during the Torgya festival. Galdan Namge Lhatse Monastery, Tawang, Arunachal Pradesh, India. January 2014.

Roland Seitre / Maroon-fronted Parrots (Rhynchopsitta terrisi) captive, endemic to Mexico. Endangered species.

Roland Seitre / Maroon-fronted Parrot (Rhynchopsitta terrisi) captive, endemic to Mexico. Endangered species.

Konrad Wothe / Silver-beaked Tanager (Ramphocelus carbo) male, Costa Rica, Central America

Sebastian Kennerknecht / Red Leaf Monkey (Presbytis rubicunda) female and male, Tawau Hills Park, Sabah, Borneo, Malaysia

Sebastian Kennerknecht / Red Leaf Monkey (Presbytis rubicunda) in tree, Tawau Hills Park, Sabah, Borneo, Malaysia

Robin Chittenden / Silver-beaked Tanager (Ramphocelus carbo magnirostris) on flower stem, Trinidad, Trinidad and Tobago, April

Alex Mustard / Maroon hermit crab / gold ring hermit crab (Pagurus hemphilli) climbs on a kelp leaf, covered in colonial seamatts. Browning Pass, Port Hardy, Vancouver Island, British Columbia, Canada. North East Pa...

Sebastian Kennerknecht / Red Leaf Monkey (Presbytis rubicunda) juvenile in tree, Danum Valley Conservation Area, Sabah, Borneo, Malaysia

Sebastian Kennerknecht / Red Leaf Monkey (Presbytis rubicunda) female foraging in tree, Tawau Hills Park, Sabah, Borneo, Malaysia

Sebastian Kennerknecht / Red Leaf Monkey (Presbytis rubicunda) mother and juvenile feeding on vines on fence, Tawau Hills Park, Sabah, Borneo, Malaysia

Sebastian Kennerknecht / Red Leaf Monkey (Presbytis rubicunda) on fence, Tawau Hills Park, Sabah, Borneo, Malaysia

Suzi Eszterhas / Maroon leaf monkey / Langur (Presbytis rubicunda) sitting in tree, Danum Valley Conservation Area, Sabah, Borneo, Malaysia

Tim Fitzharris / Cottonwood (Populus sp) trees in autumn near Maroon Bells, Colorado

Luiz Claudio Marigo / Maroon / Reddish bellied parakeet (Pyrrhura frontalis) eating banana, mountainous Atlantic Rainforest of Serra Bonita Natural Private Heritage Reserve (RPPN Serra Bonita) municipality of Camacan, Sout...

Luiz Claudio Marigo / Maroon / Reddish bellied parakeet (Pyrrhura frontalis) two perched on branch, mountainous Atlantic Rainforest of Serra Bonita Natural Private Heritage Reserve (RPPN Serra Bonita) municipality of Camac...

Luiz Claudio Marigo / Maroon / Reddish bellied parakeets (Pyrrhura frontalis) two perched on branch in mountainous Atlantic Rainforest of Serra Bonita Natural Private Heritage Reserve (RPPN Serra Bonita) municipality of Ca...

Luiz Claudio Marigo / Maroon / Reddish bellied parakeet (Pyrrhura frontalis) perched on branch in mountainous Atlantic Rainforest of Serra Bonita Natural Private Heritage Reserve (RPPN Serra Bonita) municipality of Camacan...

Luiz Claudio Marigo / Maroon / Reddish bellied parakeet (Pyrrhura frontalis) perched on branch in mountainous Atlantic Rainforest of Serra Bonita Natural Private Heritage Reserve (RPPN Serra Bonita) municipality of Camacan...

Suzi Eszterhas / Red Leaf Monkey (Presbytis rubicunda) in rainforest, Danum Valley Conservation Area, Malaysia

Birgitte Wilms / Spine-cheek Anemonefish (Premnas biaculeatus) in anemone, Solomon Islands

Juergen Freund / Shrink wrapped Yellowfin tuna steak for export, Chen Woo processing plant, Bitung, Sulawesi, Indonesia, October 2009. Fish undergoes a "clear smoke" process which turns the dull maroon fish colour int...

Murray Cooper / Maroon-tailed Parakeet (Pyrrhura melanura) pair, Ecuador

Michael D. Kern / Green tree python (Morelia viridis) maroon morph, captive, from SE Asia

Michael D. Kern / Green tree python (Morelia / Chondopython viridis) maroon morph, coiled on branch, captive, from Australia and SE Asia

Michael D. Kern / Green tree python (Morelia / Chondopython viridis) maroon morph, coiled on branch, captive, from Australia and SE Asia

Michael D. Kern / Green tree python (Morelia / Chondopython viridis) maroon morph, coiled on branch, captive, from Australia and SE Asia

Fred Bavendam / Spine-cheek Anemonefish (Premnas biaculeatus) pair living with a Bulb Tentacle Sea Anemone (Entacmaea quadricolor), Bali, Indonesia

Nick Garbutt / Maroon langur / Red leaf monkey (Presbytis rubicunda) leaping through canopy. Danum Valley, Sabah, Borneo, Malaysia

Tim Fitzharris / Quaking Aspen (Populus tremuloides) in fall colors and Maroon Bells, Elk Mountains, Snowmass Wilderness, Colorado

Hiroya Minakuchi / Red Leaf Monkey (Presbytis rubicunda), Borneo, Malaysia

Tim Fitzharris / Haystack Mountain with aspen forest, Maroon Bells-Snowmass Wilderness, Colorado

Tim Fitzharris / Quaking Aspen (Populus tremuloides) forest, Maroon Bells, Snowmass Wilderness, Colorado

Nick Garbutt / Maroon Leaf Monkey (Presbytis rubicunda) in trees. Danum Valley, Sabah, Borneo

Pete Oxford / Indian with blowdart used to shoot Maroon tailed parakeet, Llanchamacocha, Ecuador Amazon,

Chris Newbert / Spine-cheek Anemonefish (Premnas biaculeatus) juvenile, 40 feet deep, Solomon Islands

Patricio Robles Gil / Red Shining-parrot (Prosopeia tabuensis) eating berry, endemic to Fiji and Tonga

Patricio Robles Gil / Maroon-fronted Parrot (Rhynchopsitta terrisi) flock roosting, Cumbres de Monterrey National Park, Nuevo Leon, Mexico

Patricio Robles Gil / Maroon-fronted Parrot (Rhynchopsitta terrisi) pair, Cumbres de Monterrey National Park, Nuevo Leon, Mexico

Patricio Robles Gil / Maroon-fronted Parrot (Rhynchopsitta terrisi) flock roosting, Cumbres de Monterrey National Park, Nuevo Leon, Mexico

Tim Fitzharris / Maroon Bells peaks reflected in Maroon Lake, Snowmass Wilderness, Colorado