Prey traits that facilitate matings and help forage are shaped by a combination of sexual selection and natural selection as they also tend to attract predators. At the ecological scale however, prey individuals manage this predation risk by altering conspicuous traits and behaviours leading to adverse fitness consequences. Therefore, predicting any evolutionary change as an outcome of risk management requires an understanding of the underlying mechanisms governing predator-prey interactions. By developing and addressing theoretical predictions using empirical evidence collected with a combination of field experiments, enclosure experiments, and computer simulations I investigate the following research themes: (a) predation cost of mate searching and fitness consequences of prey defence responses (space use and alternative reproductive tactics), (b) scaling up of individual prey responses to emergent population mating patterns (assortative mating), and (c) the role of habitat choice in potentially structuring populations through assortative mating. Having examined species interactions at individual- and population-level, I then go on to integrate these ideas along with climate into an ecosystem-level framework, to (d) investigate the role of animals in litter decomposition across a precipitation gradient. Based on these results, I develop a framework and link it to my short- and long-term plans which include unifying prey responses in the context of foraging and reproduction, phenotype-environment matching, effect of climate on species interactions, and ecosystem function.