Precocial

Precocial development — found in ratites, waterfowl, shorebirds, grouse, and megapodes — requires substantial yolk reserves in the egg, so eggs are proportionally large relative to adult body mass. Newly hatched precocial chicks can thermoregulate independently within 24-48 hours and forage independently (though often guided by parents). The spectrum between precocial and altricial is actually a continuum, with 'semi-precocial' (gulls, terns) and 'semi-altricial' (herons) intermediate types.