So we have renewed confirmation that every human being alive today is descended from a single mother, who lived 200,000 years ago. Hallo, cousins!

The lady in question is known as mitochondrial Eve. The name comes from examining the mitochondria which are the energy factories in each human cell. Conveniently they are only inherited through the female line, and have 37 genes which rarely change. In addition they have a variable region which changes fast enough and regularly enough to time the small genetic variations which do occur.

These observations need to be matched against genetic models which use different sets of assumptions about migration, and expansion, and take into account random growth and extinction. In this study, published in the journal Theoretical Population Biology, ten different models were studied side by side – making the result the most robust and reliable to date.

Of course the genetic identification of a single ancestor does not mean that we have discovered the first woman. We know nothing about her predecessors, and it is generally thought that a number of small human populations lived in different habitats before dying out. It would appear that mitochondrial Eve mothered the only line which happened to survive.

An interesting thought strikes me. Traditional moralists have argued that there are certain extreme circumstances in which polygamy would not be forbidden by the natural law.  But polyandry is always forbidden. However, in the case of mitochondrial Eve, polyandry would certainly be beneficial in order to achieve more general genetic diversity. Indeed if there were only one woman around – and several males, polyandry would be almost inevitable. Perhaps polyandry was simply too unthinkable for the male moral theologian.

Of course this is small beer compared with a new fossil discovery, published in Nature Geoscience (also on August 17). These take us back 650 million years, and are the earliest evidence of animal body forms, somewhat like a primitive sponge – 70 million years earlier than previous evidence.

Perhaps they are our ancestors too – but this might be harder to demonstrate.


About Quentin

Science Editor, Catholic Herald. Portrait © Jacqueline Alma
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11 Responses to Grandmama

  1. Ion Zone says:

    There is also a man we are all descended from, whom scientists have called Adam, though Eve and he never met (they lived thousands of years apart).

  2. Ion Zone, i was not aware of this. Do you have anu background sources of information? I imagine that the method of tracking used must have differed the that used by women.

  3. claret says:

    When do the millions of years in millions of years become meaningless? Could these ‘sponges’ not be 651 million years old as opposed to a mere 650 million? It would appear obvious that they could be as it is only a minor difference until one remembers that the minor difference is a million years!
    I read somewhere that there is/ are tribes in the Amazon that have no concept of ‘time’ whatsoever and that we can all learn from them that time is no more than a human invention to help us cope with our surroundings.
    So these things that are spoken of in millions of years are nothing more than a description of something that has no basis in fact other than they just happened.
    If this be the case then it so happens that there is an Adam and an Eve.

  4. I can’t say that I agree with you, Claret. Just the other day I was reading a professional historian who emphasised the importance of learning dates. The reason was quite simple: with dates you know what occurred before an event, what was occurring elsewhere which might have affected the incident, and what occurred afterwards to which the event might have contributed.

    of course dates in the remote past are bound to be approximate, and often need revising. But we do need an idea of scale. And, again, we need to know sequences. It’s hard enough to trace evolution reliably even with the dates. It would be impossible without.

  5. claret says:

    But Quentin that is my point. An historian inevitably relies on time because to be an historian requires it, but suppose there is no such thing. We are so used to time that every single thing we do is measured by it and so we are lost without it as we need it to make sense of the world but our need does not make something real that is unreal.
    How can anything be dated at 650 million years old? It is a totally meaningless figure because we have no concept of it. We are happy to quote it but really can anyone grasp it? Can you explain it except by repeating it? How old is the God we believe in?
    Time is a human concept and, as such, does not exist at all and is just something we have invented that does not exist in reality.
    Things just happen. Adam and Eve happened. We are the proof of it, not time.

  6. Claret, this might get interesting. Let’s hope some others join us.

    Here’s a starting point from me. Time is a measurement of change. The criterion can vary: it might be the swings of a pendulum, or the earth going round the sun, or the annual repetition of the seasons – or a thousand other sequences of approximate regularity. From which we derive a first conclusion: before Creation there was no time. Nothingness precludes change.

    To those occurrences we need to attach a number. Thus 60 pendulum swings might make a minute or 10 sequences of 4 seasons might make 10 years. 650 million years is not in principle different from 650 minutes. While we can’t get our imaginations around that period (as I can get my imagination around the idea that about six lifetimes have passed since Elizabeth 1) that doesn’t make it any less real. Nor does it prevent us from having a conception of it. And it’s certainly important for an evolutionist or geologist to know the length of processes if they are to be better understood. their subject.

    All these measurements are relative to each other, I would agree that there is no such thing as ultimate time against which they can be compared.

    It may be that the difficulty lies in attaching the necessary number to the chosen criteria of change. Are numbers real? Or do they refer to merely human notation. There’s a problem!

  7. claret says:

    Somewhere in the recesses of my mind is a Catholic ‘teaching’ that God is outside of time. If that is the case then there must be a state in which time does not exist, and if God exists then at what point did he move from his non-time to our earthly time.
    I suppose we could refer to secular time and to sacremental being. At every Mass we engage in sacremental being because we are back at the Last Supper.
    At some point science tells us that the flow of time will be reversed does it not? So that we then end up back at the ‘Big Bang.’ (Not ‘we’ exactly but what ever is left on earth. The seas/ waters only, perhaps.)
    This is all so confusing that it brings me back to the conclusion that there is no such thing as time. But as you say I would like to see what others have to say on the subject. I feel my contribution to be a bit shallow but it helps me to have a more literal understanding of Genesis!

  8. One route in approaching the question of God and time arose because of the claim that if God could see what I was doing in the future then I must be obliged to do that. I have no freewill because all is settled in advance. But of course this does not happen, looking backwards. I know what I did yesterday but I was free at the time to choose to do it. From this the idea was derived of a God who looked down on time – as one might look down on a table. He would see past present and future – in fact the whole of time laid out as a plateau which he could observe. Of course this is a very human metaphor, and we must not repeat the frequent mistake of applying human imagination to God.
    Perhaps Jesus got as close as we can in human terms when he said “Before Abraham was, I am.” This would suggest an essential present in God, and a fluctuating, contingent, change in his creation. But the statement is metaphorical or poetic rather than a scientific proposition.
    I don’t know about scientists thinking that time must reverse. I do know that some of their sequential equations work as well backwards as they do forwards. But that’s just at a mathematical level. Then you have speculations based on the time frames of relative movement, and movement faster than light. String theory is a fertile source of bright ideas – such as the infinite repetition of universes. All of this makes our simple belief in an infinite loving God seems rather pedestrian and obvious by comparison.

  9. Horace says:

    As I understand it modern science views time as a dimension; there are the three dimensions that we are familiar with, and then a fourth dimension which is time.
    String theory even suggests that there might, in some sense, be even more dimensions – perhaps 10 or even 26!
    Sticking to the simple 4 dimensions, I see no problem in time extending to millions or billions of years any more than space extending to millions or billions of miles.

    As Quentin has hinted the trouble with considering time as a dimension becomes evident when we try to discuss ‘free will’. Even worse, to me, is the problem of consciousness itself.

    Many years ago I was working in my office when I heard sounds of a scuffle outside. I went to see what was happening and was confronted by a lady walking down the corridor towards me – with no clothes on! I said something fairly stupid like – “Can I help you?”. She replied “The world is going to end and I shall be God.” I was temporarily confused and this must have shown because she repeated herself clearly and distinctly – obviously having decided that she was talking to the local idiot. This gave me time to recover and we chatted amicably for perhaps a minute, during which time I suggested that, as it was a cold day, perhaps it would be a good thing if she put on some clothes while waiting for the end of the world. We walked, arm in arm, down the corridor to the waiting room where we found a bewildered ‘accompanying nurse’ collecting various objects of clothing from different corners of the room. Two other patients, with admirable British composure, were sitting quietly pretending that nothing unusual was happening.

    When I saw the good lady a few minutes later she informed me that she had had a ‘blackout’ in the waiting room. (The episode was, in fact, an epileptic fit.)
    From her point of view she had been unconscious.
    From my point of view I had been talking with a perfectly conscious and reasonable human being (albeit with some unusual ideas!).

    So what is consciousness? And how can we conceive of consciousness unrelated to memory and therefore ‘outside of time’?

  10. Malteser says:

    If we are all descended from one woman, just as the Church has always taught and the Bible clearly states, it seems reasonable to suppose that the Church might also be right about us all being descended from one man.

    Why are we so reluctant to recognise scientific evidence in support of Church teaching? Our atheist friends have no qualms about citing scientific evidence that (allegedly) supports their views. If we don’t wise up to this quickly, we have no chance of winning the battle with secularism.

  11. Iona says:

    (Only just caught up with this thread)
    Horace: you don’t have to assume that the lady was unconscious, even from her own point of view, while she was talking with you. She could have been in a dissociated state of consciousness, of which she had no subsequent memory.

    As for Time, it is a basic concept without which we cannot carry on our daily lives nor communicate with one another, but from a God’s-eye view it has no reality. God sees everything all at once, not because he has foresight (to see into the future) and a good memory (to see into the past) but because that’s how it is for him. He also sees our free choices; which are none-the-less free for being observed by him.

    (I can’t imagine how those Amazon tribes manage if they really have no time-related words or concepts. Can anyone tell me any more about them?)

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