Dove

A small to medium-sized bird of the pigeon family — peace symbol across cultures, the white morph used in religious imagery, and the common name shared with the genus including the rock pigeon of every city worldwide.

Dove vs. pigeon

There’s no biological distinction between “dove” and “pigeon” — both refer to members of the family Columbidae. The names are used inconsistently:

Smaller species are often called “dove.”
Larger species are often called “pigeon.”
The same species can be called either, depending on context.
“Rock pigeon” and “rock dove” are the same bird (Columba livia).

White doves used in releases at weddings or doves-of-peace symbolism are typically domesticated rock pigeons bred for the white morph.

Symbol of peace

The dove as a symbol of peace traces to:

Genesis 8 — the dove returning to Noah’s ark with an olive branch, symbolizing the end of the Flood.
Christian iconography — the Holy Spirit depicted as a dove.
Ancient Greek myth — doves sacred to Aphrodite.
Picasso’s stylized white-dove drawings during the 1940s peace movement.

The release of doves at international gatherings (UN events, Olympics, weddings) draws on this multi-culture symbolism.

Mourning dove

In North America, the mourning dove (Zenaida macroura) is among the most abundant birds — its slow descending “coo-OOO-coo” call is one of the iconic sounds of American summer. Despite their numbers, mourning doves are also one of the most-hunted gamebirds, with over 20 million taken annually. The population sustains the harvest because of their high reproductive rate.

Crop milk

Doves and pigeons produce a unique substance called crop milk to feed nestlings. Unlike mammalian milk, crop milk is a curd-like secretion from the crop lining — produced by both parents, fed to squabs (chicks) for the first 1-2 weeks. Only doves/pigeons, flamingos, and male emperor penguins produce anything analogous to milk among birds.

Passenger pigeon’s extinction

The closely-related passenger pigeon (Ectopistes migratorius) was once perhaps the most abundant bird in the world — flocks of billions darkening North American skies. Hunted for meat throughout the 19th century, the species crashed catastrophically; the last passenger pigeon, Martha, died in 1914 at the Cincinnati Zoo. Their extinction is one of the most-cited examples of human-caused biodiversity loss, and a focus of theoretical de-extinction research.