Which Came First.

Alright, I’ve had it.

Once again today I heard someone say “it’s a chicken-and-egg thing”. This refers, of course, to that stale old chestnut “Which came first, the chicken or the egg?” This trite saying is supposed to be an example of an impenetrable mystery, but it is nothing of the sort. The least understanding of biology, given a moment’s thought, easily resolves the question.

How does speciation occur? Is it by some creature starting its life as one species and ending up as another? Obviously not. New forms of life arise through mutation, through the imperfect transfer of genetic information from parent to child. So in this example something that was not-quite-a-chicken laid an egg containing the world’s first chicken.

Which came first? The egg. Move on.

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  1. The trite saying bothers me as well. I’m glad you have dispatched it.

    Posted October 22, 2005 at 7:29 pm | Permalink
  2. Malcolm says

    Thanks Bill,

    That’s a particularly irritating one. It would be gratifying if a broadside from my blog were enough to sink it for good, but I’m not optimistic.

    Posted October 24, 2005 at 11:10 am | Permalink
  3. Spur says

    Not so fast, my friend. Your explanation presupposes that the concept chicken is a sharp one, which is a highly tendentious assumption. I say that if we were to trace the evolution of the chicken backwards, we would never come across an animal about which we would say: it’s a chicken, but its mother isn’t a chicken. So I don’t think there’s an answer to the question about the chicken or the egg, though not for the usual reason.

    Posted October 29, 2005 at 12:46 am | Permalink
  4. Malcolm says

    Hi Spur,

    Chickenhood is a distinction that we get to make, and our ability to make such a discrimination is an implict precondition of the coherence of the example. If we can’t agree on what a chicken is, then we should not be using the term in allegedly serious questions. If it is important to have an answer, then define “chicken” and off you go. We do this all the time. My twenty-year-old daughter can’t drink legally now, but in September of 2006 she will be able to.

    Also, your argument doesn’t change the fact that all variation happens between generations, not within the life of a single organism.

    Posted October 29, 2005 at 1:27 am | Permalink
  5. Spur says

    The problem is that we have never sharply defined chickenhood. That’s not to say that we don’t know what a chicken is. In most cases we can say whether something is a chicken or not. But if we were to trace the evolution of the chicken backwards, we would come across borderline cases–animals that aren’t clearly chickens and aren’t clearly not chickens. And worse, the transition from definite chickens to these borderline cases wouldn’t be sharp either! Nothing about our current definition of chickenhood would allow us to settle these cases, because we haven’t defined chickenhood sharply.

    Posted October 29, 2005 at 2:43 pm | Permalink
  6. Malcolm says

    Well, Spur, you are quite right that speciation is not (with the extremely rare exception of the successful “hopeful monster”) an event that is detectable at the time it happens, but is, rather, visible only in retrospect.

    If we cared enough to make a strict genetic definition of a chicken, however, we could draw the “not-a-chicken-yet”/”yup-here’s-a-chicken” line unambiguously, and the first thing on the chicken side would be an egg. If not, then we can simply acknowledge that chickens arose through a gradual process of speciation over a span of time. But in each case any variation occurs between mother and egg.

    The point is that there is no mystery here, no paradox, and no reason to be perpetuating this hackneyed expression.

    Posted October 31, 2005 at 11:18 am | Permalink
  7. Kevin Kim says

    2010: Dinosaur Comics confirms that it’s the egg.

    See here.

    (BTW, Aristotle is saying “peisomai,” which in this context means “I shall suffer”– probably because of the headache caused by his contemplation of the chicken/egg “dilemma.”)

    Posted February 12, 2010 at 7:30 am | Permalink
  8. Malcolm says

    Excellent, Kevin! Thanks.

    Posted February 12, 2010 at 10:29 am | Permalink

One Trackback

  1. […] In a gratifying development, it appears that scientists have finally weighed in on that dimwitted question concerning the chicken and the egg. As w.w.w. readers will recall, of course, from thepost matter had in fact already been settled. […]