The Chicken and the Egg - Which came First? An Accurate, but Not Very Serious Analysis
It is one of the great questions of science and an almost equally great question of comedic potential - which came first, the chicken or the egg? In this short article I will endeavour to answer this paradox of cyclical cause and effect with a mix of light science and humour (just wade through the light science to get to the humour).
And yes - as far as I am concerned, there IS a clear and very definite answer to this question!!
The Religious Chicken and Egg
I'm a believer in science, but to briefly consider the religious perspective;
In the Judeo-Christian religions, God creates 'fowl that may fly above the earth' but makes no mention of any egg before the fowl. The assumption would therefore perhaps be that chickens come first?
In Buddhism and in some other religions including those of the ancient Mayans and Aztecs, there is a cyclical view of creation, so time repeats itself and there is no beginning. If this implies eternity, then can we make the assumption that neither comes first?
In the Hindu faith, as I understand it, chickens and other birds are created by Lord Brahma, and there is a process of destruction and renewal. But there is also the concept of a 'cosmic egg' from which all of the universe was created, including animals and birds, so in terms of original creation perhaps an egg - if not a chicken egg - comes first?
The Ancient History of the Chicken and Egg Question
You think the chicken and the egg question is a recent one? Not a bit of it. It's a question which dates back to antiquity as can be seen in this quote by Aristotle the Greek c350 BC, who also related the seeming impossibility of the conundrum to the birth of man:
- 'If there has been a first man he must have been born without father or mother – which is repugnant to nature. For there could not have been a first egg to give a beginning to birds, or there should have been a first bird which gave a beginning to eggs; for a bird comes from an egg.'
Plutarch, in the 1st century AD also saw the conundrum:
- 'the problem about the egg and the hen ... (is) ... a difficult problem which gives investigators much trouble.'
And in the 5th century AD, the Roman philosopher Macrobius appreciated that this question could be both a source of amusement to many, and also a serious question of science (much the approach that my article takes):
- 'You jest about what you suppose to be a triviality, in asking whether the hen came first from an egg or the egg from a hen, but the point should be regarded as one of importance, one worthy of discussion, and careful discussion at that.'
The Basic Assumptions
We must first start with a couple of basic assumptions so we understand exactly what we are talking about.
1) The definition of a 'chicken' is clear enough - we are talking about a bird which zoologists can classify as a chicken (Gallus gallus domesticus). But the definition of an 'egg' is less obvious. 'Egg' is a general term, and eggs have been around much longer than chickens. That is plainly apparent - dinosaur eggs, frog eggs, fish eggs - need I say more? Therefore in order to make the question worthwhile debating, we must make clear, in the question 'Which came first, the chicken or the egg', that the first basic assumption is that we are talking specifically about a chicken egg - which hatches into a chicken. Not just any old egg which hatches into a different bird or even a different animal, like a dinosaur or a frog.
2) When we talk about an egg in this context, we must also be clear whether we are talking about an unfertilised egg or a fertilised egg. I think the importance of this will immediately become very apparent. An unfertilised egg will of course break the chicken-egg-chicken-egg sequence because it won't hatch into anything - the best that can happen to it is that it will just become a boiled egg or a scrambled egg or an omelet. Therefore the second assumption we will make is that we are talking about a fertilised egg - ie: one which is capable of developing into a chicken.
In a nutshell (or an eggshell) we are therefore really asking 'which came first, the chicken or the fertilised chicken egg?' It is on this basis that the rest of the discussion below will be considered.
The Evolution of Chickens and Chicken Eggs
Where do chickens come from? And don't say from eggs, or we'll be back to square one! Chickens are birds, and birds have a long evolutionary history dating back to the time of the dinosaurs. Indeed the prevailing current opinion (and my own strongly held belief) is that birds evolved from dinosaurs. Certainly many if not all dinosaurs laid eggs so these eggs came before chickens or chicken-like birds, but as I've already declared under 'Basic Assumptions', that's just not good enough for a worthwhile debate. Of course eggs of some description came before chickens, so we must limit this specifically to chicken eggs. So let us return to relatively recent times and the most recent evolutionary change which led to a chicken.
The modern chicken is believed to have evolved from the jungle fowl of Asia. But which jungle fowl? There are two species, the red jungle fowl and the grey jungle fowl and some recent genetic evidence suggests that the domestic chicken may actually be a cross between the two species - a hybrid. If so, this may have some relevance to our question as we shall see under 'The Argument for the Egg.'
The Argument for the Chicken
So who thinks the CHICKEN came first? Well quite recently a lot of media attention promoted the case for the chicken, and it's all to do with a protein called ovocledidin-17, found only in chicken ovaries. Scientists had discovered that this protein was instrumental in controlling the development of the egg-shell. Therefore, without the chicken ovary the egg shell could not form. Some reputable scientists felt that this indicated that the chicken containing ovocledidin-17 must have come first.
This, however, is nonsense. There were proteins before ovocledidin-17 first appeared, and these were used to harden egg shells. All other birds hatch from egg shells which don't come from chickens, and so do other animals which may not have ovocledidin-17 in their egg shells, like crocodiles. Ovocledidin therefore was NOT essential in the past for hardening eggshells. Eggs developed without it.
The argument for ovocledidin-17 doesn't get rid of the cyclical conundrum either. Even if we accept the suggestion that the chicken egg could only come from a chicken containing this protein, one still has to ask, where did the first chicken containing the protein come from? Answer - presumably, a chicken egg.
The Argument for the Egg
So who thinks the EGG came first? There are three arguments in support of the egg.
1) The first argument runs along the lines that the nature of an egg is determined by what it contains, not what lays it. To clearly demonstrate this, one can use an implausible example. If a surrogate mother Tyrannosaurus rex laid an egg from which a clucking chicken emerged complete with beak and feathers, would we describe that egg as a T.rex egg or as a chicken egg? I think we would label it as a chicken egg because a chicken emerges from it. But if we label it as a chicken egg, because it produces a chicken, it does not necessarily follow that we have to call the animal which laid the egg, a chicken. In other words, in our example, no one would describe Tyrannosaurus rex as a chicken, just because it has laid a chicken egg (leastways not to its face). So by this line of reasoning, a chicken egg first and foremost hatches into a chicken. And it is only incidental that it may have been laid by a chicken.
2) The second argument concerns hybridisation. As I have already mentioned, there is a belief that modern chickens may be a hybrid between two ancestral species of jungle fowl. If this is the case, then our answer is straightforward - two birds which were not chickens got together and produced a hybrid egg which developed into a chicken. If one accepts the hybridisation theory therefore, the first chicken egg may come after the jungle fowl parents, but it most definitely comes before the first domestic chicken offspring.
3) The third argument focuses on basic understanding of mutations. Only a mutation could change a non-chicken into a chicken, and mutations can only ordinarily occur during the recombination of DNA during the process of fertilisation of the egg. Therefore, irrespective of whether the two adults are different species, (as in the above jungle fowl example) or whether they are the same non-chicken species, the mutation to a chicken occurs at the egg stage.
Analysing the Chicken and the Egg Question
So where does this leave us on this important question?
DNA is what determines a species, so the science of this is really all about the point at which the first indisputably identifiable chicken DNA appeared. DNA doesn't alter during the life of an animal or bird. It only alters during the recombination of genetic material from two different species creating a hybrid species, or the mutation of genetic material from two individuals of the same species creating a new form. Either way, the alteration which brings about definitive chicken DNA occurs at the stage when the egg is fertilised. Definitive chicken DNA therefore occurs first of all in the fertilised chicken egg, and only second in the chicken bird.
You comprehend? If not, a plain English summary will follow.
A Plain English Summary?
So we will sum up in very plain English which even a badly retarded chicken could understand. Humans may have some difficulty however - We have to decide which came first:
Did a chicken-like bird which was very similar to a chicken but not quite a chicken give rise to an egg which was sufficiently chicken egg-like to be called a chicken egg. Or did an egg which was very similar to a chicken egg but not quite a chicken egg give rise to a bird which was sufficiently chicken-like to be called a chicken? Given that mutation occurs when the egg is fertilised, any change in status occurs at this point. Therefore, in the distant past, a female chicken-like bird which was not quite a chicken formed an egg which was not quite a chicken egg. When this egg was fertilised by a male chicken-like bird which was not quite a chicken, a DNA mutation or recombination must have occurred which was just sufficient to make the chicken-like egg sufficiently chicken egg-like for us to be able to describe it as a chicken egg. So in conclusion the fertilised egg which is clearly and unarguably a chicken egg, came before the bird which is clearly and unarguably a chicken. Simple!
Is there an entry in the Guinness Book of Records for the most references to chickens and eggs in a paragraph of English, and can I submit the paragraph above? I counted 19 chickens and 15 eggs. (Though one should never count the chickens until they are hatched).
The Next Question
The next question one may ask is:
Which came first, the chicken-like fillet which is not quite a chicken fillet as it is made of soya? Or the chicken egg-like egg which is not quite a chicken egg, because it is covered in gold foil and made of chocolate?
And which is the first to be consumed?
The Egg Came First
So that's it then. The quote from Roman philosopher Macrobius elsewhere on this page indicates that the question has probably existed since the beginnings of human thought, and has always been treated in the same way by humans - a bit of a joke question yet with a serious underlying biological puzzle. The quote shows that human beings really haven't changed very much over the millenia in the way they ponder these questions. Yet if humans haven't changed, chickens and eggs clearly have. Once upon a time chickens and chicken eggs did not exist. And if they did not exist, one must have come first.
And now the answer is clear and definitive. Without a shadow of a doubt: THE EGG (fertilised chicken egg) CAME FIRST !!!
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