Many birds and animals imprint on what they see and hear at birth. Cowbird females lay their eggs in another bird’s nest and let the host bird raise their young. Yet the Cowbird fledglings do not imprint on the host bird.
Interestingly, they sneak out at night and return to the nest in the morning. The mother cowbird stays near the nest and will call to her baby. The mother’s pay close attention to whether or not their young survive. If the host mother kicks the Cowbird egg out of her nest, sometimes the mother Cowbird will destroy that host bird’s nest.
What is still a mystery is how the Cowbird babies find their way into a Cowbird flock and survive to mate. They must learn how to eat what a Cowbird eats and behave like a Cowbird to survive. This is the opposite behavior of many other birds.