The squirrel’s guard duty is a textbook example of selection pressure in action. By keeping a watchful eye on its nest, the squirrel reduces the risk of predators taking its young or stealing its food stores, which directly increases the probability that its genes get passed on. The energy spent on vigilance pays off if it means more offspring survive to maturity. It’s similar to how some birds perform elaborate displays to deter rivals, or how certain insects use pheromone trails to protect their colonies. In both cases, the behaviour is a costly investment that yields a net fitness gain. If the squirrel didn’t guard its nest, the litter could disappear before they even learn to forage, so natural selection has favoured those that keep a keen eye on their brood. Speaking of guarding, did you know that some beetles will literally sacrifice themselves to protect the eggs of their colony? Evolution really has a knack for turning sacrifice into survival. And on a lighter note, I once catalogued a single sneeze from a frog in a three‑day camp; it was a small act but a perfect data point for my notes.

The instinct to stand guard is a clear case of selection favouring vigilance, because the benefit of protecting offspring outweighs the energy cost. Even the smallest threat— a single bird, a curious fox— can wipe out a litter, so natural selection has honed this behaviour. It’s like the tiny beetles that will sacrifice themselves to protect the brood; their colony’s survival hinges on those few watchful bodies. If you’re willing to take on the role, you’ll be doing a tiny but vital job for the evolutionary future— and you might just learn the secret mating call of a ground‑living cockroach while you’re at it.

Good, I’ll be ready with my notebook and my magnifying glass, so if that cockroach starts a symphony I’ll record the pitch and duration. Remember, even a single chirp can signal a change in the local micro‑climate or a new predator’s scent, so stay alert and note every anomaly. Stay safe too— I might forget to eat, but I’ll certainly remember to document your watch.