Polly may want a cracker, but if Polly is an African gray, she'll likely be able to ask for more than just that. With good socialization, either a Congo or timneh African gray parrot can be a loving pet for decades.
Geography
Both Congo and timneh African gray parrots come from Africa, but are common in different parts of the continent. Congo African grays evolved in Central Africa, ranging from the Ivory Coast to western Kenya, and as far south as Tanzania and Angola. The geographic range of the timneh is much smaller, concentrated along the coastal areas of western Africa, including Guinea, Ghana and the Ivory Coast.
Size and Color
Although many African gray parrots look almost identical, there are differences between the Congo and timneh parrots. Congo African gray parrots are larger than timneh. Congos can be up to 14 inches tall and weigh approximately 1 pound. The smaller timneh usually only grows 10 inches tall and weighs 6 ounces less than the Congo.
The two parrots have slight differences in color. The timneh is a dark, charcoal grey, while the Congo can range from dark to light grey. The timneh also has a pink upper beak, but the Congo has a solid black beak. The tail feathers of the Congo African gray are bright red, but the timneh has dark maroon tail feathers.
Personality
Both types of African gray parrots are intelligent, cautious birds. Dr. Irene Pepperberg from the University of Arizona estimated in 1995 study that they have the intelligence of a 5-year-old child and the temperament of a 2-year-old. Both Congos and timnehs will bond with their human caregivers, but Congos generally only like one person at a time, while the timneh circle often extends to more members of the family.
Timneh African grays are often considered to be calmer and more even-tempered than their larger relatives. The timnehs mature quicker, have fewer anxiety issues and suffer less from nervous feather plucking. While Congo and timneh African grays can make fantastic pets with the right socialization and training, a timneh may be a better choice for a novice bird owner.
Talking Ability
Both timneh and Congo African grays are generally great talkers. Since timnehs mature quicker, they will often begin using words and simple sentences at 6 months of age. Many Congos don't start talking until after they are a year old.
Most Congos will mimic the voice of the person they are talking to. In contrast, most timnehs have their own voices, which has been compared to a munchkin from "The Wizard of Oz" movie or a small child.