Egg embryo is adequately developed it hatches, i.e. breaks out of the egg's shell. Some embryos have a temporary egg tooth they use to crack, pip, or break the eggshell or covering. The largest recorded egg is from a whale shark, and was in size. Whale shark eggs typically hatch within the mother. At and up to , the ostrich egg is the largest egg of any living bird, though the extinct elephant bird and some dinosaurs laid larger eggs. The bee hummingbird produces the smallest known bird egg, which weighs half of a gram (around 0.02 oz). Some eggs laid
Bare-faced go-away-bird in two disjunct areas in Africa: one in Ethiopia, and the other in Burundi, DRC, Kenya, Malawi, Rwanda, Tanzania, Uganda and Zambia. It occurs in open woodland, thickets and in cultivation with scattered trees. It may be found up to 1,400 m, but at Loita up to 2,200 m in scattered cedar, acacia and evergreen scrub. Two geographically isolated races are accepted: These birds primarily eat fruits, leaf buds, and seeds. Like other Touracos, the bare-faced go-away-bird lays two to three greenish-white eggs each mating season. Nests are often built in tall acacia trees. Bare-faced go-away-bird The bare-faced go-away-bird ("Corythaixoides