Behaviour 2019
I like it striped! Banded shrimps occupy more habitats than non-banded ones
Marco Elias1, Arthur Anker1, Felipe Gawryszewski2. 1Universidade Federal de Goiás, Goiânia, Goiás, Brazil; 2Universidade Federal de Goiás, Goiânia, Goiás, Brazil; 3Universidade de Brasília, Brasília, Distrito Federal, Brazil

Striped species are known as examples of disruptive coloration, making their detection difficult. However, stripes can also work as motion-dazzle, disrupting the perceived speed, working well for small-sized species. Thus, striped preys may reduce the detection via disruptive coloration and, after detection, reduce the chances of capture via motion-dazzle. This would enable them to survive in a larger range of habitats than non-striped preys, which are often background matched and dependent of habitat colours to concealment. To test this, we gathered data on colour, ecology, and body size of snapping shrimps (Alpheus). Using images, information on body size, habitat use, and controlling relatedness, we show that stripes are more likely to evolve in habitat generalists. This was corroborated by qualitative and quantitative approaches. Both suggested this effect to be stronger for smaller species, but the latter revealed an interaction of habitat use and size on the colour contrast: smaller generalists had higher contrasts than average-sized and specialists. Predators, body size, and frequency of habitats are likely to have influenced the evolution of colour patterns in alpheids.