Spiders fluoresce under UV light and possess a huge diversity of fluorophores. Remarkably, spiders are the only known group in which fluorescence is "taxonomically widespread, variably expressed, evolutionarily labile, and probably under selection and potentially of ecological importance for intraspecific and interspecific signaling". A study by Andrews et al. (2007) reveals that fluorescence has evolved multiple times across spider taxa, with novel fluorophores evolving during spider diversification. In some spiders, ultraviolet cues are important for predator-prey interactions, intraspecific communication, and camouflaging with matching fluorescent flowers. Differing ecological contexts could favor inhibition or enhancement of fluorescence expression, depending upon whether fluorescence helps spiders be cryptic or makes them more conspicuous to predators. Therefore, natural selection could be acting on expression of fluorescence across spider species.