[saghm]

You have the draw the line _somewhere_ though, right? If not biologically, at least linguistically we don't call other birds chickens, and we don't call other animals with shared common ancestors chickens, and I don't think that you can argue that the common ancestors of chickens and, say, primates, can be referred to as both "human" without being prescriptivist to the point that you'd be dictating rules that essentially zero English speakers actually follow.

To be clear, I don't disagree with you that my argument makes little sense biologically; my point is that the question itself is phrased in a way that doesn't really parse correctly in a scientific sense. To me, it reads more like a semantics question (i.e. it depends on your definition of "chicken" and "egg) because the only way to get a scientifically precise answer is to expand the definition of "chicken" beyond recognition.

[nurettin]

Yes, we need to draw a line and the question seems flawed. Sure, it makes you think, it is funny, but it contains an invalid assumption that the line's width is a single generation. If we assume that the question is about species, it takes thousands of generations for an offspring not to be able to reproduce with its ancestors.