What is the primary factor that influences the size difference between male and female raptors?

The primary factor that influences the size difference between male and female raptors is sexual selection. In many raptor species, this phenomenon leads to a distinct size dimorphism, where females are significantly larger than males. This size difference can be attributed to various evolutionary pressures, primarily tied to reproductive strategies.

Females, being the ones to incubate eggs and care for the young, benefit from having a larger body size. A larger female can produce and support more offspring and may also be better equipped to defend the nest against predators. Males, being smaller, can more effectively pursue prey and can have a wider range when hunting, which is beneficial for feeding the female and their young.

Sexual selection often manifests through the preference of females for larger mates, which can also drive the evolution of size differences between genders. Additionally, size can reflect the health and vigor of potential mates, making sexual selection a profound influence on the physical characteristics of raptors over time.

The other suggested factors, such as diet during youth, flight skills, and intra-species competition, either play less direct roles in determining size differences or are more related to individual development and survival rather than the overarching trends seen between male and female raptors. Therefore, sexual selection stands out as