Domestic chicken used evolve, it's super effective! The first known chicken to be born without an egg has surfaced in Sri Lanka.
Via: bbc.co.uk
Evolution or freak occurrence?
This adorable baby, born in Sri Lanka, is the first known "live birth" chicken. Under normal conditions, domestic chickens will lay a clutch of eggs over several days and then incubate them with their bodies for a gestation of approximately three weeks.
However, in this case the chick hatched inside the mother hen and was incubated for 21 days internally before being born. While the baby is happy and healthy, the hen unfortunately did not survive. An autopsy revealed she died to to internal injuries, which is to be expected since chickens are not (currently) equipped for live birth.