Humans Turning Animals into Night Owls

Kaitlyn Gaynor et al., in a study published in Science in June, found that in areas of high human activity, animals are choosing to conduct more of their own affairs at night. Animals in such areas were 36 percent more active at night as opposed to day compared to animals in areas where human activity is lower. The results were drawn from a meta-analysis of 76 papers and covered 62 species of larger mammals across six continents. The nocturnal shift is occurring irrespective of the type of human activity (e.g., hunting, resource extraction, agriculture, development). What remains to be determined is what effect this turn toward nocturnality will have on the animals themselves and the ecosystems they inhabit, particularly as humans continue encroaching on wildlife habitat.