When is a Statement Scientific?

Some right wing religious commentators are upset about this article by biologist Greg Hampikian (to my embarrassment I got involved in one such debate and was overwhelmed by the level of feeling). What is interesting about this is the nature of the accusation. For example:

such utter, scientifically false rubbish that it leaves one gasping

“An anti-ID biology professor who doesn’t even know the facts of life, let alone evolution

“Junk Biology Promotes Uselessness of Men

In other words commentators are not just disagreeing with the feminist message (I tend to agree with them) but implying that Hampikian has asserted something that is scientifically false. Furthermore it is not just false, but obviously false. So, given Hampikian’s qualifications the only logical conclusion is that he is lying and lying in a crude way that will easily be discovered.

When it comes down to it there are  three things that Hampikian asserted that have been called scientific errors:

  • That the father’s sperm does not merge with the mother’s egg.

I must confess this does seem wrong and I don’t understand what he is getting at.  The sperm is completely absorbed by the egg which seems to be as about merged as you can get.

  • Women are both necessary and sufficient for reproduction, and men are neither.

Discussions of necessary and sufficient are always a bit tricky as there are almost always some kind of implied conditions.  Only a very special set of statements are necessarily true under all conditions – mathematical statements, statements that are true by definition etc.  Clearly with current technology male sperm is required for reproduction and the only way we know to make such sperm is from a man.  So women are not sufficient. I think perhaps Hampikian was referring to the fact that the sperm could have been created many months or even years before fertilisation. So it is not necessary to have a man around for conception. The other possibility is that he was referring to fact that the technology exists to manufacture DNA and insert it into an egg – although we are a long way from manufacturing a complete set of male DNA – while we have no concept of how to manufacture an egg.  It is a rash statement by Hampikian which is open to many interpretations – but this was an opinion piece not a scientific paper.

  • Identifying “you” with the unfertilised egg in your mother’s womb.

This is the one that really got people excited.  They felt that this was clearly biologically wrong – that “you” were created when the egg was fertilised. 

It is easy to see why this is important to people  with certain religious and political beliefs.  They want to clearly identify the creation of an individual with fertilisation because they also believe that destroying the embryo at any point after fertilisation, i.e. early abortion, is tantamount to murder.  Hampikian is identifying the individual with an even earlier stage in the process of development, but anything that blurs the link between fertilisation and creation of an individual is contrary to some religious beliefs.

I don’t want to dispute whether fertilisation is the point where an individual is created. I would only say that it is not a scientific question.  If you believe in the soul and think that is the point where the soul is linked to the embryo then it is a theological question.  If you are concerned about the rights of the embryo it is a legal question. If you are concerned about the ethics of abortion or research on embryos it is an ethical question.  Or you may simply regard it is a matter of definition – how do you define “individual”.  But none of these are scientific issues.  Scientists know a lot about the chemistry and biology of reproduction and, with the possible exception of his statement about sperm not merging, everything that Hampikian wrote is consistent with what is known (as you would expect from a professor of biology).

What evidence do commentators produce to back up their assertion that this a gross scientific error? There are quite a lot of assertions that it is obviously true and anyone disagreeing is guilty of obfuscation – but this is not evidence.  The only real evidence is extracts from biology textbooks about fertilisation such as

Human development begins at fertilization [with the joining of egg and sperm, which] form a single cell called a zygote. This highly specialized…cell marks the beginning of each of us as a unique individual.

and

a new, genetically distinct human organism is formed.

These need a bit of dissection. It is a scientific statement to say when a cell becomes genetically distinct and when development begins. But Hampikian does not say anything about either of these.  He just writes about “you” which is not a scientific term.  On the other hand statements about what marks the beginning of us an individual or human organism is a matter of definition. These terms carry much more with them than science. When something is a human individual is very much an open debate and has many emotional, legal, religious and other connotations.  Two scientists could agree on every detail of the chemistry and biology, they could make an identical film of what happens, but still differ as to whether to call the fertilised egg an  individual.  Indeed some scientists have identified other (later) stages in the development process with the start of the individual including syngamy, implantation in the uterus, and 14 days after fertilisation (when the embryo can no longer split into more than one individual).  This was not the result of experiments or careful observation as to when the individual began.  It was a definition based on a different interpretation of known facts based on concerns which are outside the science.

This whole thing needs putting in perspective. It is an opinion piece. The whole idea is present interesting, novel and possibly controversial ways of looking at thiings. Hampikian is simply using the non-scientific word “you”, with all its emotional connotations, to give such a view of your origins. Had he been trying to make a different point he might have wrote about how you used to be trillions of disparate atoms scattered about the earth which came together in an organised way.  Some sociologists might talk about how you were the result of sociological forces that defined your role in society.  Some psychologists might talk about the factors in your early childhood that made you into an individual human being. This is an Op Ed piece not a science text book. Of course Hampikian knows the basics of human reproduction as does every kid who has done school science.  To suggest that he was trying to mislead the public on this is absurd.

9 Responses to “When is a Statement Scientific?”


  1. 1 Neil Rickert September 3, 2012 at 2:25 pm

    I’m glad to see your blog is again active.

    I looked at the NYTimes article, after seeing a post on that at UD. My take was that Hampikian was being intentionally speculative and provocative, especially provocative.

    My choice was to stay out of the discussion. I didn’t want to defend Hampikian, since I don’t agree with him. On the other hand, I thought the accusations that he was scientifically illiterate were absurd. I’m not sure why people can’t tell that he was being deliberately provocative.

    • 2 Mark Frank September 3, 2012 at 2:35 pm

      Neil thanks. I regret getting involved with that particular discussion but the issue of what is scientific and what is not is kind of interesting.

      • 3 Neil Rickert September 3, 2012 at 3:24 pm

        My take would be that there is no such thing as a scientific statement. There are statements by scientists, but that’s not the same thing. Science is an institution, which encompasses ways of investigating nature. But science isn’t a person and does not make statements.

        I’ve disagreed with Jerry Coyne on the same sort of issue. He sometimes says words to the effect that science refutes religion. But it doesn’t. It is silent on the question. It may lead many scientists to be highly skeptical of religion (and rightly so, in my opinion). But it is not the nature of science itself to make such judgements.

        My point: We should avoid treating statements by people (even by prominent scientists) as if they were statements by science.

        Rather than saying “that statement is scientific”, I should more appropriately say “that statement is consistent with current scientific knowledge” and even then I should add “in my opinion.”

  2. 4 petrushka September 4, 2012 at 3:33 pm

    Didn’t I read somewhere that more than 90 percent of the mutations carried by a human individual originate in sperm. That indicates to me that most purifying selection happens at or just before fertilization. So while males are not absolutely necessary, and some species seem to have done away with them or made them optional. they may be an important source of variation and fecundity.

    Do any of the programs that model population genetics model this feature of maleness? Am I off the cliff?

    Is it even possible to select for evolvability in this sense? Is there any consensus as to why sex?

    • 5 Mark Frank September 4, 2012 at 3:44 pm

      I am not a biologist but I think the largest source of variation comes from crossing over between the genomes rather than mutation of one or other gamete.

    • 6 Neil Rickert September 4, 2012 at 4:42 pm

      Didn’t I read somewhere that more than 90 percent of the mutations carried by a human individual originate in sperm.

      I am not a biologist, either, but that does seem likely. The ova are produced early in the life of the woman, and preserved for a long time. Sperm are being continuously produced. I expect that there’s a lot more opportunity for mutation to occur in sperm than in ova.

      Is there any consensus as to why sex?

      I’m not sure. I have been surprised to read, in many places, that sex is a puzzle. Yet, to me, it seems obvious. I’m looking at it in terms of learning theory, and from that perspective you need the recombinant genetic engineering that occurs with crossovers, so as to maintain variation within the population.

      This is why I sometimes say that I am not a neo-Darwinist. The Darwinists want natural selection to be a filter that reduces variation. I say that variation is important, and is what protects a population from going extinct. So, for me, the production of potentially useful variation (as opposed to natural selection) is the most important part of what drives evolution.

      • 7 petrushka September 4, 2012 at 5:42 pm

        It seems to me there is utility in producing zillions of potential offspring having an elevated mutation rate, and eliminating those having fatal mutations before you invest much in rearing them.

        The difficult part is figuring out how such a system could evolve and be maintained. I think that’s where the controversy lies.

  3. 8 petrushka September 4, 2012 at 4:36 pm

    But over time the sequences change. This is where I’m just making a wild conjecture. but It would seem that sequence changes or point mutations would be more likely fatal than crossover. So if a species is going combine the ability to evolve with the ability to avoid the dreaded genetic meltdown, then you need fecundity and purifying selection.

    It just strikes me as not a coincidence that sexually reproducing species produce hundreds of millions of sperm for every one that successfully passes on its genes, AND sperm for various reasons have a higher mutation rate than eggs. (Mostly because they are the result of more divisions.) So species that produce few offspring seem to subject themselves to a rate of purifying selection comparable to that of single celled organisms.

    I’m not a biologist either, and this is just a wild conjecture. But I wonder if it is modeled in software.


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