Some tarantula species exhibit pronounced sexual dimorphism. Within species there is considerable variation in patterns of sexual dimorphism. Males and females exhibit no sexual dimorphism. Some species of anglerfish also display extreme sexual dimorphism. Evidence suggests a negative correlation between sexual size dimorphism and incidences of sexual cannibalism. Anole lizards show prominent size dimorphism with males typically being significantly larger than females. Members of the genus exhibit strong sexual dimorphism. Polygynous primates have the highest sexual dimorphism, and polygamous and monogamous primates have less. Similar sexual dimorphism and mating choice are also observed in many fish species. The degree of sexual dimorphism varies by subspecies. Chloroplasts in plants are notable as they exhibit a distinct chloroplast dimorphism. The species does not display any obvious sexual dimorphism. In addition, the breed exhibits sexual dimorphism with females having more angular heads than males. He gave as examples sexual size dimorphism and mimicry. The bird is one of many bird species to exhibit marked sexual dimorphism.