Sentinel Duty in Animal Behavior

During my seven years in the army, I was in a survey crew. Our job was to go out into the wilderness and survey objects to be fired upon by the artillery unit. Because we were accustomed to being on our own and concealing our movement with the terrain and natural objects, we were frequently assigned sentinel duty. That meant our survey crew was deployed around the perimeter of where our unit was sleeping for the night. We were there to watch for any enemy coming close to our unit. In combat, we were especially vulnerable, because we had no protection ourselves, and were frequently in enemy territory. Sentinel duty was essential for the survival of the whole unit, but it was a dangerous duty.

Animals also practice sentinel duty. Birds are especially adept at having sentinels during their migratory journeys when they are vulnerable to hawks, wolves, foxes, cats, snakes, and a wide variety of mammals. Studies have shown that most birds migrating in groups have a single bird to watch for predators while the other birds in the flock are foraging. Because sentinels are by themselves, easy to identify, and further from a place of safety than the rest of the flock, they are frequently the first to be eaten.

For humans, giving your life to protect the group is considered a moral responsibility. Why would a bird serve as a sentinel? If you believe in “survival of the fittest,” then being a sentinel makes no sense at all. You and your progeny can be quickly removed from the population, and any beneficial DNA you may have had is gone forever. Sentinel duty does not select the most fit of the flock and allow them to survive and produce more offspring.

Many animal behaviors in the natural world do not promote the survival of the individual but contribute to the group’s advancement. Sentinel duty seems to be built into life-forms to allow survival in a constantly changing environment. God has designed a wide variety of behaviors into living things to enable Earth to be full of every kind of living creature. Sentinel duty is one of those genetically programmed behaviors.

— John N. Clayton © 2020