Do animals really have instincts?

Across the animal kingdom, different species seem to have instinctual ways of finding their way through life: Newly hatched sea turtles that know to reach the ocean by moonlight, birds that migrate thousands of miles as the seasons change, and lioness mothers that know to nurse, protect and teach their young. But are these really instincts?

Before we ask how instinct works, we need to know what instinct is.

"To talk about instinct really is not possible unless you are also talking about the other side of the coin, which is acquired or learned [behaviors]," Robert Lickliter, a developmental psychobiologist at Florida International University, told Live Science.

In other words, "instincts" are actually behaviors influenced by factors that aren't immediately obvious. For instance, scientists long thought that imprinting — a behavior in which poultry, including turkey, geese, chicken and duck hatchlings, somehow identify and follow their mother — was an instinct: an innate, predetermined, genetically formed tendency that seemed unexplainable.

But starting in 1963, developmental psychologist Gilbert Gottlieb made a revolutionary discovery: Duck hatchlings are attracted to their mother's vocalizations because they make their own vocalizations inside the egg as an embryo, priming their auditory systems before they are even born. Gottlieb's duckling experiments pioneered a new understanding of what we mean by "instinct" and whether hardwired behaviors exist at all.

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As with the duckling example, other influences can happen before birth, while an organism is still developing.