Why are vertical elements, such as tall perches or upper levels, recommended in an Andalusian run?

Answer

To satisfy their instinct to roost high for safety against ground-based threats like hawks and owls.

Because Andalusians are capable flyers and need vertical exploration, incorporating tall roosting areas helps satisfy their instinct to seek height for safety against aerial predators, even when housed in a managed setting.

Why are vertical elements, such as tall perches or upper levels, recommended in an Andalusian run?
SpacehousingChickenAndalusianRearing