Marie Read / Ruby-throated Hummingbird (Archilocus colubris), male flying in to feed from cardinal flowers (Lobelia cardinalis) New York, USA. August.

Marie Read / Northern cardinal (Cardinalis cardinalis) male perched amid snow-covered branches, New York, USA, February.

Alan Murphy/ BIA / Northern Cardinal (Cardinalis cardinalis) male and Pyrrhuloxia (Cardinalis sinuatus) male fighting, Texas

Alan Murphy/ BIA / Northern Cardinal (Cardinalis cardinalis) female flying, Texas

Donald M. Jones / Pyrrhuloxia (Cardinalis sinuatus) male feeding on Ocotillo (Fouquieria splendens) flowers, southern Arizona

Alan Murphy / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Alan Murphy / Northern Cardinal (Cardinalis cardinalis) male, Texas

Alan Murphy / Pyrrhuloxia (Cardinalis sinuatus) female, Texas

Jeff Rotman / Symbiotic emperor shrimp (Periclimenes imperator / Zenopontonia rex) living in the gills of a spanish nudibranch (Hexabranchus sanguineus) Red Sea, Egypt

B&S Draker / Northern Cardinal (Cardinalis cardinalis) male eating Possum Haw Holly (Ilex decidua) berries. Bandera, Hill Country, Texas, USA.

Steve Gettle / Northern Cardinal (Cardinalis cardinalis) male, Brighton, Michigan

Rolf Nussbaumer / Northern Cardinal (Cardinalis cardinalis) male feeding young Brown-headed Cowbird (Molothrus ater) New Braunfels, San Antonio, Hill Country, Central Texas, USA

Rolf Nussbaumer / Northern Cardinal (Cardinalis cardinalis) male perched on branch of Crape Myrtle (Lagerstroemia) New Braunfels, San Antonio, Hill Country, Central Texas, USA

LYNN M. STONE / Female Northern Cardinal (Cardinalis cardinalis) perched on branch in snow storm, Illinois, USA

Jack Dykinga / Scarlet monkey flowers {Mimulus cardinalis} and White firs {Abies concolor} at base of steep canyon walls, Fork North Creek, Zion National Park, Utah, USA

Jack Dykinga / Flowering Lobelia (Lobelia cardinalis) beside a pool with submerged Yellow pond lily (Nuphar polysepala) and Cypress (Taxodium sp) in El Cielo Biosphere Reserve, Tamaulipas, Mexico

Rolf Nussbaumer / Northern Cardinal {Cardinalis cardinalis} male drinking from pond, Hill Country, Texas, USA

Rolf Nussbaumer / Northern Cardinal {Cardinalis cardinalis} female in flight, Hill Country, Texas, USA

TOM MANGELSEN / Northern cardinal fluffed up in tree. (Cardinalis cardinalis) Montana

Rolf Nussbaumer / Northern cardinal male bathing {Cardinalis cardinalis} Texas, USA

Rolf Nussbaumer / Northern cardinal, juvenile male {Cardinalis cardinalis} Texas, USA

David Tipling / Cardinal lory (Chalcopsitta cardinalis) in flight. Savo Island, Solomon Islands.

Magnus Lundgren / Wild Wonders of China / Free swimming juvenile spanish dancer (Hexabranchus sanguineus) in the night, Kenting National Park, Hengchun Peninsula, Taiwan

Magnus Lundgren / Wild Wonders of China / Free swimming juvenile spanish dancer (Hexabranchus sanguineus) in the night, Kenting National Park, Hengchun Peninsula, Taiwan

Heather Angel / Scarlet monkey flower (Mimulus cardinalis). The high position of the stamens and stigma ensure that the heads of hummingbird pollinators make contact with them whilst nectaring. Cultivated in garden,...

John Shaw / Yellow-billed cardinal (Paroaria capitata). Pantanal, Brazil, September.

Marie Read / Backyard setup for photographing Ruby-throated Hummingbirds (Archilocus colubris) in summer, New York, USA. A natural food plant (cardinal flower (Lobelia cardinalis)) in a floral tube of water is tie...

Marie Read / Backyard setup for photographing Ruby-throated Hummingbirds (Archilocus colubris) in summer, New York, USA. A medical syringe is used to inject a few drops of sugar solution into the flower (set up in...

Marie Read / Northern Cardinal (Cardinalis cardinalis) female perched amid berries and seedheads with falling snow, New York, USA. November. Non-ex.

Marie Read / Bird-friendly garden in full bloom in summer, New York, USA, including purple coneflowers (Echinacea purpurea) and green-headed coneflowers (Rudbeckia laciniata), black-eyed susans (Rudbeckia sp.), be...

Alan Murphy/ BIA / Northern Cardinal (Cardinalis cardinalis) male, Texas

David Fleetham / Imperial commensal shrimp (Periclimenes imperator / Zenopontonia rex) on Spanish dancer nudibranch (Hexabranchus sanguineus) at night. Philippines.

Karine Aigner / Portrait of a Northern cardinal (Cardinalis cardinalis) female with white background, Block island, Rhode Island, USA. Bird caught during scientific research.

E.J. Peiker/ BIA / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Alan Murphy/ BIA / Northern Cardinal (Cardinalis cardinalis) feeding on berries, Texas

Alan Murphy/ BIA / Pyrrhuloxia (Cardinalis sinuatus) male flying, Texas

Alan Murphy/ BIA / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Alan Murphy/ BIA / Pyrrhuloxia (Cardinalis sinuatus) male on cactus, Texas

Alan Murphy/ BIA / Northern Cardinal (Cardinalis cardinalis) male, Texas

Alan Murphy/ BIA / Pyrrhuloxia (Cardinalis sinuatus) female on prickly pear catus, Texas

Alan Murphy/ BIA / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Ingo Arndt / Giant painted locust (Phymateus saxosus) Isalo National Park, Madagascar

Ingo Arndt / Giant painted locust (Phymateus saxosus) Isalo National Park, Madagascar. August.

Ingo Arndt / Giant painted locust (Phymateus saxosus) Isalo National Park, Madagascar. August.

Ingo Arndt / Giant painted locust (Phymateus saxosus) Isalo National Park, Madagascar. August.

Ingo Arndt / Giant painted locust (Phymateus saxosus) Isalo National Park, Madagascar. August.

Thomas Marent / Vermilion Cardinal (Cardinalis phoeniceus) female, Guajira Peninsula, Colombia

Thomas Marent / Vermilion Cardinal (Cardinalis phoeniceus) male, Guajira Peninsula, Colombia

Thomas Marent / Vermilion Cardinal (Cardinalis phoeniceus) male feeding on seed, Guajira Peninsula, Colombia

Thomas Marent / Vermilion Cardinal (Cardinalis phoeniceus) male, Guajira Peninsula, Colombia

Steve Gettle / Northern Cardinal (Cardinalis cardinalis) male, North America

Lorraine Bennery / Giant painted locust (Phymateus saxosus) mating, Andringitra National Park, Madagascar, November.

Lorraine Bennery / Giant painted locust (Phymateus saxosus), Andringitra National Park, Madagascar, November.

Jack Dykinga / Northern cardinal (Cardinalis cardinalis) male on the ground, Catalina State Park, Arizona, USA, May.

Rolf Nussbaumer / Northern Cardinal (Cardinalis cardinalis), adult male perched on icy branch of Christmas cholla (Cylindropuntia leptocaulis), Hill Country, Texas, USA. February

Rolf Nussbaumer / Northern Cardinal (Cardinalis cardinalis), adult male perched on icy branch of Possum Haw Holly (Ilex decidua) with berries, Hill Country, Texas, USA. February

Rolf Nussbaumer / Northern Cardinal (Cardinalis cardinalis), adult male perched on icy branch of Possum Haw Holly (Ilex decidua) with berries, Hill Country, Texas, USA. February

Rolf Nussbaumer / Northern Cardinal (Cardinalis cardinalis), adult female eating Elbow bush (Forestiera pubescens) berries, Hill Country, Texas, USA. May

Rolf Nussbaumer / Northern Cardinal (Cardinalis cardinalis), male eating Elbow bush (Forestiera pubescens) berries, Rio Grande Valley, South Texas, Texas, USA. May

Roger Powell / Northern cardinal (Cardinalis cardinalis) male singing over breeding territory, La Chua Trail, Paynes Prairie, Reserve, Gainsville, Florida, USA April

Mary McDonald / Pyrrhuloxia (Cardinalis sinuatus) at feeding station near pond, Madera Canyon, Arizona, USA, April.

Mary McDonald / Pyrrhuloxia (Cardinalis sinuatus) in tree near pond, Madera Canyon, Arizona, USA. April.

Tony Wu / Spanish dancer nudibranch (Hexabranchus sanguineus) scavenging the reef at night in Ambon, Indonesia

Alan Murphy/ BIA / Pyrrhuloxia (Cardinalis sinuatus) male perching on cactus, Texas

Alan Murphy/ BIA / Pyrrhuloxia (Cardinalis sinuatus) female, Texas

Alan Murphy/ BIA / Northern Cardinal (Cardinalis cardinalis) male flying, Texas

Nate Chappell/ BIA / Northern Cardinal (Cardinalis cardinalis) fledgling begging for food from male, Texas

Nate Chappell/ BIA / Northern Cardinal (Cardinalis cardinalis) and Pyrrhuloxia (Cardinalis sinuatus) males fighting, Texas

Marie Read / Northern cardinal (Cardinalis cardinalis) male (right) feeding his mate in spring as part of courtship/pair formation, termed "allofeeding", New York, USA, May.

Marie Read / Northern cardinal (Cardinalis cardinalis) male (right) feeding his mate in spring as part of courtship/pair formation, termed "allofeeding", New York, USA, May.

Marie Read / Northern cardinal (Cardinalis cardinalis) male (right) feeding his mate in spring as part of courtship/pair formation, termed "allofeeding", New York, USA, May.

Bernard Castelein / Rainbow Milkweed locust (Phymateus saxosus) near Tsaranoro massif, Andringitra NP, Madagascar

Nate Chappell/ BIA / Pyrrhuloxia (Cardinalis sinuatus) pair, Texas

Donald M. Jones / Pyrrhuloxia (Cardinalis sinuatus) male atop a cactus, southern Arizona

Donald M. Jones / Pyrrhuloxia (Cardinalis sinuatus) male feeding on Ocotillo (Fouquieria splendens) flowers, southern Arizona

Donald M. Jones / Pyrrhuloxia (Cardinalis sinuatus) male feeding on Ocotillo (Fouquieria splendens) flowers, southern Arizona

Donald M. Jones / Pyrrhuloxia (Cardinalis sinuatus) male feeding on Ocotillo (Fouquieria splendens) flowers, southern Arizona

Donald M. Jones / Pyrrhuloxia (Cardinalis sinuatus) male feeding on Ocotillo (Fouquieria splendens) flowers, southern Arizona

Donald M. Jones / Pyrrhuloxia (Cardinalis sinuatus) male feeding on Ocotillo (Fouquieria splendens) flowers, southern Arizona

Claudio Contreras / Northern cardinal (Cardinalis cardinalis) male perched, Laredo Borderlands, Texas, USA. April

Claudio Contreras / Northern cardinal (Cardinalis cardinalis) male perched, Laredo Borderlands, Texas, USA. April

Claudio Contreras / Northern cardinal (Cardinalis cardinalis) male perched, Laredo Borderlands, Texas, USA. April

Claudio Contreras / Northern cardinal (Cardinalis cardinalis) female perched, Laredo Borderlands, Texas, USA. April

Claudio Contreras / Northern cardinal (Cardinalis cardinalis) female, Laredo Borderlands, Texas, USA. April

MYN / JP Lawrence / Northern cardinal (Cardinalis cardinalis) male, Oxford, Mississippi, USA. Meetyourneighbours.net project

MYN / JP Lawrence / Northern cardinal (Cardinalis cardinalis) male, Oxford, Mississippi, USA. Meetyourneighbours.net project

MYN / JP Lawrence / Northern cardinal (Cardinalis cardinalis) male, Oxford, Mississippi, USA. Meetyourneighbours.net project

MYN / JP Lawrence / Northern cardinal (Cardinalis cardinalis) male, Oxford, Mississippi, USA. Meetyourneighbours.net project

MYN / JP Lawrence / Northern cardinal (Cardinalis cardinalis) male, Oxford, Mississippi, USA. Meetyourneighbours.net project

Gerrit Vyn / Adult male Pyrrhuloxia (Cardinalis sinuatus) at desert water hole. Starr County, Texas. March.

Gerrit Vyn / Northern cardinal (Cardinalis cardinalis magnirostris) Starr County, Texas, USA. March.

Alan Murphy / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Alan Murphy / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Alan Murphy / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Alan Murphy / Pyrrhuloxia (Cardinalis sinuatus) male, Texas

Alan Murphy / Northern Cardinal (Cardinalis cardinalis) male flying, Texas