How Horror Works, II

The most effective monsters of horror fiction mirror ancestral dangers to exploit evolved fears. For most of human evolutionary history, we have faced threats in the domains of predation, conspecific violence, contagion, status loss, and dangerous nonliving environmental features. We thus very easily acquire fears directed toward threats from these domains. This chapter argues that the nonrandom distribution of human fears is reflected in horror, which features stimuli that mirror evolved fears, often in incarnations that are exaggerated and/or counterintuitive for increased salience, including giant spiders, supernormal monsters such as evil clowns, and physics-violating ghosts. Many monsters are also equipped with contagion cues, thus exploiting an evolved disgust mechanism. Some monsters evoke moral disgust through their violation of norms. To strengthen audiences’ emotional responses to such monsters, horror artists often provide descriptions of characters’ reactions which are mirrored by the audience through an adaptive mechanism enabling emotional contagion.

Non-paradoxical evolutionary stability of the recombination initiation landscape in Saccharomycetes

The nonrandom distribution of meiotic recombination shapes heredity and genetic diversification. A widely held view is that individual hotspots — favored sites of recombination initiation — are always ephemeral because they evolve rapidly toward extinction. An alternative view, often ignored or dismissed as implausible, predicts conservation of the positions of hotspots if they are chromosomal features under selective constraint, such as gene promoters. Here we empirically test opposite predictions of these theories by comparing genome-wide maps of meiotic recombination initiation from widely divergent species in the Saccharomyces clade. We find that the frequent overlap of hotspots with promoters is true of the species tested and, consequently, hotspot positions are well conserved. Remarkably, however, the relative strength of individual hotspots is also highly conserved, as are larger-scale features of the distribution of recombination initiation. This stability, not predicted by prior models, suggests that the particular shape of the yeast recombination landscape is adaptive, and helps in understanding evolutionary dynamics of recombination in other species.