Dunnock relatively lower success for females. In times of scarcity, female territories expand to accommodate the lack of resources, causing males to have a more difficult time monopolizing females. Hence, females gain a reproductive advantage over males in this case. The dunnock possesses variable mating systems. Females are often polyandrous, breeding with two or more males at once, which is quite rare among birds. This multiple mating system leads to the development of sperm competition amongst the male suitors. DNA fingerprinting has shown that chicks within a brood often have different fathers, depending on the success of the males at monopolising
Common kestrel name "tinnunculus" is Latin for "kestrel" from "tinnulus", "shrill". Common kestrel The common kestrel ("Falco tinnunculus") is a bird of prey species belonging to the kestrel group of the falcon family Falconidae. It is also known as the European kestrel, Eurasian kestrel, or Old World kestrel. In Britain, where no other kestrel species occurs, it is generally just called "the kestrel". This species occurs over a large range. It is widespread in Europe, Asia, and Africa, as well as occasionally reaching the east coast of North America. It has colonized a few oceanic islands, but vagrant individuals are generally rare;