The Toadflax Saga – episode two

In tonight’s episode: a long-lost cousin turns up, Lin gets called a monster by a Swede, Charles reverts to type, and alternative views of life battle for the Gould medal.

(If that’s all too much, skip to the end for a film on the dangers of wearing a large cardboard saxophone in public)

 

Before diving into the tangled story of Linaria again, here’s the cousin: a similar plant which has also been reclassified by botanists. It’s Misopates orontium, known in English not very flatteringly as Weasel’s Snout, also as Lesser Snapdragon – which is not a surprise because it used to be in the Antirrhinum (snapdragon) genus. These family and name changes remind me of soap-opera storylines: I can imagine the reclassified species crying:  ‘But I just don’t know who I am anymore!’

 Linaria and the snapdragons have had cameo roles to play in the long-running story of evolution (Beast-enders? Sorry). It all started with the Swedish botanist Carl Linnaeus  (1707-78, above), Professor of Medicine at Uppsala University, and perhaps  the most important biologist  of the 18th century.  In a colossal labour he brought together all that was known about plants in the whole world till that point, and if that wasn’t enough he included all animals as well in his great monument, the binomial system of names for all living things (i.e. genus  and species ).

In 1742 a botanical student named Liöberg  found, growing on an island near Stockholm, a plant whose flowers resembled those of Linaria vulgaris but which instead of being symmetrical either side of a vertical plane (known as zygomorphic), were radially symmetrical (or actinomorphic), having five equal petals and five spurs.  Here is a photo of a modern version, from a blog which tells this story too – well  worth a look here.

 

Eventually this conundrum came the way of Linnaeus, who was most discomfited by the discovery, since he believed strongly that all species were created separately by God and hence could not change.  He assumed it must be a hybrid with an unknown plant and in 1744 called the plant Peloria – the Greek for ‘monster’. The example was discussed by Charles Darwin over a century later, when he had  studied the snapdragon (Antirrhinum majus) in detail : the members of this similar genus also hybridise easily and show occasional radial symmetry. Darwin showed that peloric flowers were not hybrids but bred true, and published his findings in 1868 in The variation of plants and animals under domestication .  He regarded it as a possible reversion to a previous evolutionary stage, describing it as:

… an actual, though partial, return to the structure of the ancient progenitor of the group. If this view be correct, we must believe that a vast number of characters, capable of evolution, lie hidden in every organic being. But it would be a mistake to suppose that the number is equally great in all beings. We know, for instance, that plants of many orders occasionally become peloric; but many more cases have been observed in the Labiatæ and Scrophulariaceæ than in any other order; and in one genus of the Scrophulariaceæ, namely Linaria, no less than thirteen species have been described in a peloric condition.  On this view of the nature of peloric flowers, and bearing in mind what has been said with respect to certain monstrosities in the animal kingdom, we must conclude that the progenitors of most plants and animals, though widely different in structure, have left an impression capable of redevelopment on the germs of their descendants.

(The variation of plants and animals under domestication [1868] , Ch. 13, available here)

Later still, when the science of genetics had developed, it was assumed that the ‘monster’ of radial symmetry or ‘pelorism’ was due to the mutation of a gene.  Recently it has been shown that in fact vertically symmetrical (zygomorphic) and peloric flowers have the same genes, and the difference is in how they are controlled by ‘an extensive, heritable methylation of the gene’( more detail here).

This is the sort of half-chance that can be seized on by anyone with an anti-Darwin axe to grind.  For example, by Googling Linaria and evolution I came across a website apparently about Darwin, and on it a blog post for April 3rd 2011 (here),  in which the author recounts the Peloria story but concludes that since the genes are the same in peloric and non-peloric plants there is no mutation and hence ‘the foundational evidence for evolution is a legacy of facade and outright fraud.’ Despite the author’s  having a biological degree, this seems to be because he has confused the fact that one gene is identical in the two plants, with the idea that the whole DNA of the two forms is identical – well, that combined with misunderstanding of how science develops and some wilful bias. He concludes that: ‘The Linaria story highlights why evolution, while once a theory in crisis during the twentieth century, is now in crisis without a theory’.

Though in the story he tells he makes it clear he is nostalgic for the days of Linnaeus’s religious beliefs, the name of the site, the nature of the posts, and his account of himself appear scientific and do not mention a religious view. In his section about himself the author writes that his site:

….  presents the history of evolution with a time-line of discoveries, people, and ideas. With over a century of unprecedented biological research since the publication of The Origin of Species, now is the time to reflect on the scientific evidence of evolution. This blog is a forum for focusing on one of today’s hottest and contentious topics – evolution.

I can imagine a school student looking for essay material helping  themselves to a lot of this – I was a psychology lecturer and I know all about cut-and-paste essays.  The concealment of  the real purpose of  blogs like this seems to me to be both deliberate and  dishonest:  hoping to attract students and steer them towards unfounded opinions and wilful misinterpretations which masquerade as scientific evidence written by a scientist.

This author is not the only one – his ‘Reference Library’ gives a list of people who have published religious tracts dressed up as respectable science – I have come across some  before, for example a man who has put biology videos on Youtube which don’t mention his real agenda.

All this subterfuge is not accidental.  A couple of posts ago I mentioned Stephen Jay Gould and his unwavering campaign, together  with the American Civil Liberties Union, against the teaching of creationism in schools. Promoters of the literal truth of Genesis used to have American law on their side:  all teaching of evolution in schools was banned till as recently as 1968, when the proscription was overturned.  However, even then, as Gould notes in this article,  biology textbook publishers continued to cater for the religious market by not mentioning evolution in books aimed at schools – so that he himself, one of the theory’s most eloquent exponents, could not study it until he went to college.  From that point the only channel left open to creationists was to present their ideas as ‘science’ and to demand time on the science curriculum – a strategy tried in Arkansas and defeated in court in 1981 with the aid of Gould on the witness stand.  The battle is far from over and clearly this strategy of deception is still the path of a many producers of professional-looking internet resources.

I leave the last words to Gould:

The argument that the literal story of Genesis can qualify as science collapses on three major grounds: the creationists’ need to invoke miracles in order to compress the events of the earth’s history into the biblical span of a few thousand years; their unwillingness to abandon claims clearly disproved, including the assertion that all fossils are products of Noah’s flood; and their reliance upon distortion, misquote, half-quote, and citation out of context to characterize the ideas of their opponents. [Stephen Jay Gould, “The Verdict on Creationism”, The Skeptical Inquirer, Winter 87/88, pg. 186]

Now, that saxophone: I was overjoyed to find that the cleverly named Polish band Pink Freud have released a video which just seems made for this blog post:

Coming up next: a lovely flower, a short write-up, and a perfect song.

 

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2 Comments

Filed under Linaria, Misopates

2 responses to “The Toadflax Saga – episode two

  1. Ceridwen

    A splendid post. And I had never heard of weasel’s snout.
    There are whole museums devoted to the promotion of creationism you know.http://www.guardian.co.uk/science/2012/jun/06/evidence-creation-museum . I could weep.

    • I hadn’t seen that Guardian item – we miss lots of things now we don’t have the paper edition. At least the efforts of Gould and others mean that public money isn’t going into this fantasy. I could get started on faith schools too – better get back to the botany.

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