Can a Chicken become a cock?

Sex-changing animals
Actually the chicken can and does change sex, a well know fact among egg farms. The known occurences happen about every 1 in a 10,000. We have observed an egg-laying hen change into a crowing/breeding rooster. There are numerous explanations for this most having to do with the keeping the species going. But it is observed in egg-laying barns where no roosters have been present that a hen will change.

There are some animals that change sexes, but the chicken isn't one of them. I recall a marine biologist I once met telling me that all very large groupers -- the ones that weigh hundreds of pounds -- are females because only mature specimens can grow that large and all groupers change to females as they mature. It's called sequential hermaphroditism. When males turn into females, it's called protandry, and when it's the other way around, it's called protogyny. Only fish and some invertebrates demonstrate sequential hermaphroditism.
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