Mourning Doves were everywhere in the part of rural Georgia where I grew up. For the longest time I thought their name was ‘Morning’ Dove. Eventually it sunk in that their low drawn out call sounds like someone in mourning (slow learner am I). Their calls are therefore nostalgic to me, so it’s good that we have many Mourning Doves right here in Peachtree Park.
The Mourning Dove is also known as the Turtle Dove, American Mourning Dove or the Rain Dove, and was once known as the Carolina Pigeon or Carolina Turtledove. It is one of the most abundant and widespread of all North American birds. The bird is a strong flier, capable of speeds up to 55 mph. 
Pigeons and doves constitute the bird family Columbidae, which includes about 310 species. The Mourning Dove is a part of this family as is the Rock Pigeon which is ubiquitous in parking lots and on on the heads of statues all over the world. 
A Mourning Dove’s nest is constructed of twigs, conifer needles, or grass, and is of flimsy construction. Mourning doves will sometimes requisition the unused nests of other mourning doves, other birds, or even mammals such as squirrels.  You will find heir nests in dense shrubbery, in the ranches of evergreens and even on the ground.
Like other members of the Columbide family, the mourning dove drinks by suction, without lifting or tilting its head. It often gathers at drinking spots around dawn and dusk.  Sometimes, first thing in the morning, if I start down the steps towards the backyard I’ll startle a dozen or more drinking from the edge of the pond and off they’ll go with their trademark whistling sound created by their wings.
Mourning Doves eat almost exclusively seeds, which make up more than 99% of their diet. Rarely, they will eat snails or insects. Mourning Doves generally eat enough to fill their crops and then fly away to digest while resting. They often swallow grit such as fine gravel or sand to assist with digestion. The species usually forages on the ground, walking but not hopping. 
References and Additional Information
 Wikipedia: Mourning Dove
 The Sibley Guide to Birds, second edition – David Allen Sibley
 Cornell – All About Birds: Mourning Dove
 Cornell – All About Birds: Mourning Dove – sound
 The Breeding Bird Atlas of Georgia – UGA Press: Schneider, Beaton, Keyes and Klaus, Eds.
 Wikipedia: Columbadie