Studies have shown that sympatric speciation appears to occur more often in predator free environments. Without the threat of predators males can display more elaborate and colorful traits (Higashi, Takimoto, & Yamamura, 2009). This can be observed in many lake dwelling species of cichlids. A new color or different pattern could be a way to compete with stronger males of the common color or patterns (Elmer, Lehtonen, & Meyer, 2009). Without having to worry about predators they would not have to worry about remaining camouflaged.

Competition and differences in environmental resources are some other factors that can lead to sympatric speciation (Thibert-Plante & Hendry, 2011). Thibert-Plante and Hendry found that without mate choice sympatric speciation never occurred. Their study also revealed that mate choice alone was not enough and that it has to be paired with a difference in available resources or competition.

Elmer, K., Lehtonen, T., Meyer, A. (2009). Color assortative mating contributes to sympatric divergence of neotropical cichlid fish. Evolution. 63(10), 2750-2757.

Higashi, M., Takimoto, G., & Yamamura, N. (1999). Sympatric speciation by sexual selection. Nature, 402(6761), 523-526.

Thibert-Plante, X., & Hendry, A. (2011). Factors influencing progress toward sympatric speciation. Journal Of Evolutionary Biology, 24(10), 2186-2196.