Prof. Lloyd Morgan made some interesting experiments in the
instincts of birds, by rearing chickens and wild fowl from an
incubator, so that they never could have learned anything from
their parents. He found that they needed to be taught almost
everything necessary to the proper conduct of their lives--not
only to distinguish what was good to eat, but even the very
acts of eating and drinking. They showed no fear of the human
race, and plainly did not understand the language of their own
mother when he placed them near her. The mothercluck of the hen
had no meaning for the incubator chick, who nevertheless came
promptly when he called. These experiments proved conclusively
that young birds are taught--or learn by imitation, which is
the same thing--to eat and drink, to understand their native
tongue, to recognize and procure their food, and to fear
mankind.--OLIVE THORNE MILLER, “The Bird Our Brother.”
(1775)