Bee hummingbird
A newly hatched bee hummingbird chick may weigh about a fingernail clipping. Its weight is less than a tenth of an ounce (2 g). Because of this, it is the smallest living bird as well as the smallest theropod dinosaur on record. Females grow to up to  long, weighing around . Male bee hummingbirds grow to be  long, weighing around .