Respuesta :
Birds are vertebrate, warm-blooded animals that walk, jump, or stand only on the hindlimbs, [3] while the forelimbs have evolved into wings that, like many other unique anatomical features, they allow, in most cases, to fly, although not all of them fly. They have a body covered with feathers and, sensu stricto birds, a horny beak without teeth. To reproduce they lay eggs that hatch until they hatch.