Scientists' responses to this question were, according to *this piece* in today's Guardian UK, among the things that started Rupert Sheldrake's apostasy from his brother scientists.
The truth is, these scientists didn't actually know how pigeons find their way home, but couldn't admit it, and so tried to jam their answers into the dogmatic boxes they'd made for themselves. Hence they were the very opposite of scientific, and acted like theologians or priests.
Science postulates that there's an area in the brain that's religious. Hence religion is innate to us, and it doesn't matter what the religion's about, whether God, politics, philosophy, economics, or anything else. We have the innate propensity to believe, and what we believe becomes so much who we think we are that we're prepared to die for it, and some of us actually do.
This also means we have to get rid of those whose beliefs threaten our own. We usually do this by killing them, or banishing them from polite society by ensuring they can't get work again, or simply by laughing at them.
Whenever a group of the like-minded congregate around an idea, the idea soon becomes dogma, and the group quickly assumes all the characteristics of a church.
We're all Believers.