Mallee fowl spend nine to eleven months a year preparing a 3ft by 6ft (1 metre by 2 metre) mound that will act as an incubating nest. The eggs are laid in this nest and covered by soil and vegetation. The decomposing vegetation generates heat to keep the eggs warm. During the incubation period adult birds check the temperature of the nest using their beaks and alter the composition of the mound to maintain a temperature around 90 degrees Fahrenheit (33 degrees Celsius).
When the eggs hatch, the chicks break out of their shells, crawl through 2 feet of the nest material, and then can immediately run into scrub. Within 24 hours of hatching they can fly. Neither the mother nor father mallee fowl give their offspring any more attention or training, yet instinct alone is sufficient for them to behave exactly as their parents did as adults.
A number of creationist have claimed that the mallee fowl could not have arisen by evolution, due to the requirement for everything to be working together, and the inability of evolution to create complete complex systems at once.