Tuesday, 31 May 2016
Edser Gonna Roll
One of the inherent features of science is that ideas proposed as hypotheses will always be tested to exhaustion in the attempt to disprove them, not in order to dethrone the scientist, but to ensure the progress of science follows as true a path as possible. that’s not to say it is the perfect 100% truth, but the closest we can get to it as tested by a broad spectrum of methods, all approaching the idea and prodding at its cracks. If an idea is not a valid explanation of a phenomenon, then the cracks will spread and the hypothesis will crumble. If it stands up to the onslaught, it is integrated into the wider understanding of the Universe and new hypotheses are proposed on the back of it. Hence, “standing on the shoulders of giants”.
What science is not is a big pot into which you can toss random pieces of information gleaned from a range of sources because they seem to support your argument. Science is a blind process, led by data in very small steps towards nowhere in particular, other than an increased realisation that we are nowhere near a comprehensive understanding of Life, the Universe and Everything. Scientists are, by definition, full of self-doubt and cautious in making sweeping statements. Their comfort zone is an infinitesimally thin slice of confidence defined by the sensitivity and robustness of the tools with which hypotheses are tested.
The whole problem with the world is that fools and fanatics are always so certain of themselves, and wise people so full of doubts.
Bertrand Russell (1933) “The Triumph of Stupidity”. In: Mortals and Others: Bertrand Russell's American Essays, 1931-1935, vol.2. Routledge.
With annoying regularity, there are a few, certain individuals who creep out of the wiring to forward their, at best, pseudoscientific ideas. These aren’t even out and out believers having a go for Jeezus. They are often independent researchers on the margin of academia, with an obsession for trying to persuade others that they have made a world changing discovery in evolutionary theory, or that we need to rewrite history, according to their version of events. It’s basically trolling, and unfortunately I seem to number in their target group, alongside the more obvious, usual suspects, Richard Dawkins, Brian Cox, etc. etc. etc.
It’s “Me, me, me”, with "You, you, you"
One persistent character, if he manages to slip around a Twitter block, or tracks you down to some other forum, is John Edser, a self-styled independent researcher with a bone to pick: he advocates old style Darwinism and not reductionist neo-Darwinism most popularised by Richard Dawkins’ "The Selfish Gene".
Edser is trying to undo forty year’s worth of progress in gene-centred biology. He’s also got a huge chip on his shoulder about being kicked off Dawkins’ old website forum, most probably for arguing the toss. His bean focusses on a detail of Bill Hamilton’s formulae for altruism amongst genetic relatives,
“ ”selfish genism" only represents a gross misuse of W.D. Hamilton's oversimplified model of Darwinism, created to allow the evolution of organism fitness altruism in nature, which in Darwinism is prohibited as a falsification. Hamilton's rule rb>c is only a tautology. This means cause and effect reverses when it is misused as RD routinely misuses it, as a bona fide theory.”
Edser is alluding to Hamilton's Rule which predicts that genes should increase in frequency within a population
when rB > C, where
r = the genetic relatedness of the recipient (i.e.,probability that a gene picked randomly from each at the same locus is identical by descent)
B = the additional reproductive benefit gained by the recipient of the altruistic act,
C = the reproductive cost to the individual performing the act.
Spelt out, altruism occurs when a relative will benefit more than the cost to the altruist. For example, female red squirrels in Yukon, Canada, adopt orphaned pups if they are sufficiently closely related, and she doesn’t have too many in her own brood; females always adopt orphans when rB > C, but never when rB < C. The major suggestion here is that all behaviour is selfish because under the right conditions, there is always a profit to be made from being generous.
Helping relatives, who are essentially partial copies of you, to survive is equivalent to helping a fraction of yourself to survive, as conjured up by your genome/DNA (r=1/2 for children and siblings, r=1/4 for grandchildren, r=1/8 for 1st cousins, etc.). The ultimate might be to salvage a costly situation by sacrificing yourself to save them, for example, by drawing a predator’s attention away, while also alerting the others to the threat. One outcome is that you all get annihilated, ending the gene-line there and then. Alternatively, if you can successfully intervene, it’s just possible that some of your genes will survive the day to perhaps get passed on to future generations. This apparently selfless process contributing to natural selection is therefore called kin selection, and the only exception to this is when individuals are clones, such as honeybees and Imperial Stormtroopers and Young Conservatives, for which a special case of eusocial kin selection applies.
So, this altruistic martyrdom is just an optimal solution for selfishness because, ultimately, individuals only have themselves in mind as natural selection works at the level of the gene, and individuals are the culmination of all the characteristics coded in their genome. Emergence is a popular term in modern biological sciences, and you could say that the self is an emergent property of gene interaction, and in higher organisms, the interaction of neurones in generating sentience. However, much of an individual and their behaviour remains deterministic, based upon their genetic code. This is the source of another huge misunderstanding by Selfish Gene naysayers like Edser, but also the reason for the recent hysteria over epigenetics, namely that natural selection acts on genes, including genes that code for proteins that moderate the expression of other genes.
If genetics includes inheritance of changes in DNA sequences, for example, because of mistakes made when making copies of genes, then epigenetics has been coined as the umbrella term for all other heritable changes that do not involve direct changes to DNA, including the influence of environment and the accumulation of experiential adaptations. This is counterintuitive and most probably contradicts what most people were taught at school and college, that the Weismann barrier makes feedback from cells to genes impossible, so adaptations gained during a lifetime can’t be passed on, meaning Lamarckian evolution was always wrong, and it took Darwin to come along and put things right. Well, better at least. Without the tempting idea that Darwin was a beard-hair’s breadth away from encountering Mendel’s pea genetics, Darwin was at a disadvantage when it came to particulate inheritance. He got the big picture pretty much correct, but we can’t very well blame him for being a bit sketchy on molecular biology. Nonetheless, given how far off he was with Pangenesis, it would be funny to see his later leanings towards Lamarckianism being partially vindicated by epigenetics.
If epigenetic modifications are not direct changes to genes, then they must include any additional factors that can be added onto the structure of DNA to moderate gene expression. One example of this type of modification is tagging by DNA methylation. Methylation is thought to be central to controlling the differentiation of stem cells, into liver or muscle cells, etc., but also less helpfully, it’s also implicated in cardiovascular disease, cancers and ageing. The biochemical process adds methyl (-CH3) groups onto cytosine nucleotides occurring early in a gene sequence, where they then physically block progress along the DNA of the large protein complexes that form factories for gene expression. Effectively, a gene is switched off, but what controlled the off switch? The answer, of course, is another gene, so this interaction of genes is ultimately traceable back to a genetic sequence.
Jerry Coyne puts it this way,
“… gene expression is itself caused by differences in DNA sequence, and that those regulatory bits of DNA evolve precisely like “structural” genes themselves? And why on earth must “flexibility” reside more on changes in gene expression than on the structure of proteins themselves? We have no idea whether changes in gene regulation evolve more rapidly than changes in gene structure. Finally, Dawkins himself emphasizes the interactive nature of genes in The Selfish Gene, using another metaphor that of genes as individuals rowing in a crew boat (the organism). They all have to stroke in harmony to make the boat move, but you can still make it move faster by substituting a stronger oarsman for a weaker one. Selection often proceeds by that route: replacing one gene form with another in a way that keeps the vehicle—the organism—moving forward.
Further, there’s no sharp distinction between “regulatory” and “structural” genetic elements … some bits of DNA that regulate others themselves produce proteins: the so-called “transcription factors”. And a change in a gene making a transcription-factor protein (the famous Hox genes are one example) can cause changes in how other genes are regulated. A mutated “regulatory” protein, for example, can change how it interacts with the genes it regulates, so that a structural gene has regulatory effects.”
You nit of selection
When Darwin wrote about natural selection, even without the genetics at hand, he had the equivalent of kin selection in mind. He did have a huge amount of accumulated evidence and field observations, but then again so did Alfred Russel Wallace. Yet Wallace upheld the alternative concept that natural selection operates on groups of individuals, and this is the version of evolution that Edser is harking back to, except he is not so much resurrecting a phoenix from the ashes, as excising a shrivelled corpse.
At the time, when it was still young and gay, the debate was vibrant, with differences in opinion over the scale or unit of natural selection continuing well into the 1960s, largely fuelled by group selection champion, Noble prize winning zoologist Konrad Lorenz. Then along came Bill Hamilton and his Rule was the final nail in the coffin for group selection, and with it died the old saying, “for the good of the species”. There was only the individual, with relatives at increasing genetic distances.
A compromise of a multi-level selection, including group selection, was proposed by David Sloan Wilson and Elliott Sober. Think of a nested set of Russian matryoshka dolls, where each doll is a subsequent selection level: proceeding, gene, cell, individual, group. Despite the lack of evidence, group selection continues to attract it’s defenders, most notably sociobiologist Edward O. Wilson in a surprise about turn, and less so Edser in predictable consistency, despite the growing evidence in support of Hamilton’s explanation for altruism. Ironically, Edser sees classic Darwinism as being threatened by gene-centrism and suggests that Hamilton, a left-wing sociologist, was politically motivated to artificially ensure that animal behaviour exhibited altruism alongside the long-held view of “Nature, red in tooth and claw”. The conclusion has to be that Edser seems confused.
One important source of Edser’s confusion is the definition of the Hamilton equation parameters, in relation to units of selection. They have received a lot of attention, mainly because “benefits” are very difficult to assess and can be a mixture of direct and indirect influences. But he is wrong about the misuse of Hamilton’s work, and his claim that it lacks supporting evidence. Part of the problem lies in failing to recognise that the rule is a generality, expanding the definition of relatedness to include social bonding, and the multifarious delivery of benefits making them intangible and hard to identify. Importantly, the rule is not equally applicable under restrictive conditions (Birch 2013).
Nonetheless, in addition to the surrogate mother squirrels, the correctly applied rule has been demonstrated in favouritism for relatives in sun-tailed monkey colonies, within extended human families in South African townships, and as a motivation for sounding alarm calls and alerting groups of relatives in a number of species, etc., etc., etc.. There has also been an important maths-based analysis that confirms the statistical validity of the parameters in Hamilton’s original formulation (Rousset 2015). The evidence is mounting, atop a pile that is already insurmountable. He’s tried many times to get noticed, but his argument is confused and easily dismissed. It’s time; Edser really should find a new obsession.
Edser has been invited to respond here but prefers to screengrab text from his computer and upload it to Twitter. The result is that it is not possible to read what he writes because it is too small, nor search back through his past comments, making it difficult to understand quite what he is saying. Twitter is also transient and limiting for debate and excludes a wider audience who might want to comment. For that reason we are at a stalemate. *
− − − − − − − − − − − − − − − − − − − − − − − − −
Apologies to Denis Noble (Oxford) for mistaking him for Edser. I hope he didn't see, or if he did, he didn't mind my mistake. Thanks to Joachim for pointing it out.
Jonathan Birch (2013) Hamilton’s rule and its discontents. The British Journal for the Philosophy of Science 65, 2, 381-411.
François Rousset (2015) Regression, least squares, and the general version of inclusive fitness. Evolution 69, 11, 2963–2970.
* Seagoon: Stalemate!
Moriarty: Stale mate? It was fresh this morning mate!
Spike Milligan & Larry Stephens (1956) The Nasty Affair At The Burami Oasis, The Goon Show, 7(1). Recorded: 30/9/56.