Sources : Magpie

Pliny the Elder [1st century CE] (Natural History, Book 10, 50; 10, 59): [Book 10, 50] When magpies notice a person observing their nest with special attention, they transfer the eggs somewhere else. It is reported that in the case of these birds, as their claws are not adapted for grasping and carrying the eggs, this is effected in a remarkable manner: they place a sprig on the top of two eggs at a time, and solder it with glue from their belly, and placing their neck under the middle of it so as to make it balance equally on both sides, carry it off somewhere else. [Book 10, 59] A certain kind of magpie is less celebrated, because it does not come from a distance, but it talks more articulately. These birds get fond of uttering particular words, and not only learn them but love them, and secretly ponder them with careful reflection, not concealing their engrossment. It is an established fact that if the difficulty of a word beats them this causes their death, and that their memory fails them unless they hear the same word repeatedly, and when they are at a loss for a word they cheer up wonderfully if in the meantime they hear it spoken. Their shape is unusual, though not beautiful: this bird has enough distinction in its power of imitating the human voice. But they say that none of them can go on learning except ones of the species that feeds on acorns, and among these those with five claws on the feet learn more easily, and not even they themselves except in the two first years of their life. - [Rackham translation]

Martial (xiv.73): A chattering pie, I with intelligible voice salute you, my master / did you not see me you will say I am no bird. [Pica loquax certa dominum te voce saluto. / Si me non videas, esse negabis avem.]

Isidore of Seville [7th century CE] (Etymologies, Book 12, 7:46): The magpie [pica], as if the word were ‘poetic [poetica], because they pronounce words with a distinct articulation, like a human. Perching on the branches of trees, they sound out in unmannerly garrulity, and although they are unable to unfold their tongues in meaningful speech, still they imitate the sound of the human voice. - [Barney, Lewis, et. al. translation]

Thomas of Cantimpré [circa 1200-1272 CE] (Liber de natura rerum, Birds 5.104): The magpie is a very clever bird. As Pliny says, when it sees that a man is looking at its the nest, it transfers the eggs to another place, but having no claws, it puts two twigs under the eggs, so that, having been subjected to some glue from its belly, then by placing its neck in the middle, it carries the eggs balanced on the twigs. The white and black bird is a distinct variety. It establishes its nest among the thorny places, and tries to fortify it with the utmost care, with the nest on the ground inside, and the thorns on the outside all around and above, leaving only the narrowest opening through which it can enter and exit, and this in the place where the nest is most accessible. The meat of its chicks, it is said, can be eaten up to the eyes; however, unless they have been first skinned, do not yield easily to cooking. This bird, too, when it knows that it has been caught in a snare, is unmoving with its whole body, and labors to open the snare with the effort of its beak alone, and does not move the rest of its body, which is affected by despair. Pliny: Caught in its youth it can learn new words, but sometimes dies overcome by the difficulty of words. Accordingly, unless they hear from time to time what they have learned, the memory of the learning fails. They will rejoice in a strange manner if they hear again that word which they had forgotten. They choose words by thought and do not hide their intention. They have broad tongues that imitate human speech. In ancient times the Caesars had young birds fluent in Greek and Latin, discussing the day and constantly talking about new things. - [Badke translation/paraphrase]