Early experience affects foraging behavior of wild fruit-bats more than their original behavioral predispositions

There are immense consistent inter-individual differences in animal behavior. While many studies have documented such behavioral differences, often referred to as individual personalities, little research has focused on the underlying causes and on determining whether they are innate or based on individual experience. Moreover, most studies on animal personalities have described consistent differences in behavior under laboratory conditions. We aimed to examine the impact of the early experienced environment on individual animal behavior, and to compare it to that of the individuals original genetic predisposition. Additionally, we explored the correlation between personality traits measured indoors and the animals outdoor behavior. We studied Egyptian fruit bats, in which vast behavioral variability and plasticity have already been demonstrated. We raised bats in a captive colony under either enriched or impoverished environments and assessed their personality under controlled laboratory conditions. We then released the bats into the wild and tracked their foraging using GPS. Bats that had experienced an enriched environment during early life displayed increasing boldness and exploratory behavior when foraging outdoors, demonstrating how early-life experience can affect adult behavior. The individuals original predispositions did not predict their later foraging behavior. Our findings shed new light on the interplay between innate and experienced-based effects on individual behavior. Significance statementAnimals exhibit individual personalities, but how they are shaped is unknown. By employing controlled manipulations on new-born bat pups and GPS-tracking them outdoors as adults, we reveal that the early life conditions bats are exposed to have a significant impact on their foraging behavior as adults. We moreover show that the original individual predispositions of the bats do not predict their behavior. These findings enhance our understanding of the developmental factors that shape animal behavior and emphasize the vital importance of environmental enrichment during early life stages.