Wednesday, October 10, 2018

Birds, all birds, and nothing but birds

I know, just when you thought it was ok to go back into the water. He’s back!! But rest assured this is a short one and I could not resist. It appears (see here) that biology has forsaken everything that our cognoscenti have taught us about evolution. We all know that it cannot be discontinuous. We all knowthat the continuity thesis is virtually conceptually necessary. We all knowthis because for years we have been told that the idea that linguistic facility in humans is based on something biologically distinctive that only humans have is as close to biologically incoherent as can be imagined. Anybody suggesting that that what we find in human languagemightbe biologically distinctive and unique is a biological illiterate. Impossible. Period. Creationism!

Well guess again. It seems that the bird voicebox, the syrinx, is biologically sui generis in the animal kingdom and “scientists have concluded that this voice box evolved only once, and that it represents a rare example of a true evolutionary novelty” (1). 

But surely they don’t mean ‘novelty’ when they say ‘novelty.’ Yup, that is exactly what they mean:

“It’s something that comes out of nothing,” says Denis Dubuole, a geneticist at the University of Geneva in Switzerland who was not involved with the work. “There is nothing that looks like a syrinx in any related animal groups in vertebrates. This is very bizarre.”

Now, as the little report indicates, true novelties are “hard to come by.” But, as the syrinx indicates, they are not conceptually impossible. It is biologically coherent to propose that these exist and that they can emerge. And that their distinctive properties are exactly what people like Chomsky have been suggesting is true of the recursive parts of FL (4).

They are innovations—new traits or new structures—that arise without any clear connections to existing traits or structures. 

Imagine that, no clear connections to other traits on other species or ancestors. Hmm. Are these guys really biologists? Probably not, or at least, not for long for very soon their credentials are sure to be revoked by the orthodox guardians of EvoLang. Save me! Save me! The discontinuitists are coming!

The report makes one more interesting observation: these kinds of qualitatively new innovations serve as interesting gateways for yet more innovation. Here, the development of the syrinx could have enabled songs to become more complex and biologists speculate that this might in turn have led to further speciation. In the language case, it is conceivable that the capacity for recursion in languageled to a capacity for recursion more generally in other cognitive domains. Think of arithmetic as a new song one can sing when hierarchical recursion has snuck in.  

Is all of this correct? Who knows? Today the claim is that the syrinx is a biological novelty. Tomorrow we might find out that it is less novel than currently advertised (recall for Minimalists, FL is unique but not thatunique. Just a teensy weensy bit unique). What is important is not whether it is unique, but the fact that biology and evolution and genetics have nothing against unique sui generic one of a kind features. They are rare, but not unheard of and not beyond the intellectual pale. That means that entertaining the possibility that something, say hierarchical recursion, is a unique cognitive capacity is not living out on the intellectual edge in evolutionary La-La land. It is a hypothesis and one that cannot be dismissed by assuming that this is not the way biology works or could work. It can so work and seems even to have done so on occasion. That means critics of the claim that language is a species specific capacity have to engage with the actual claims. Hand waving is simply dishonest (and you know who you are). 

Moreover, we know how to show that uniqueness claims are incorrect: just (ha!) show how to derive the properties of the assumed unique organ/capacity from more generic traits and show how the trait/organ under consideration could have continuously evolved from these using very itty bitty steps. Apparently, this was done for fingers and toes from fish fins. If you think that hierarchical recursion is “just more of the same” then find me the fins and show me the steps. If not, well, let’s just say, that the continuists have some work ahead of them (Lucy, you have some explaining to do) if they want to be taken seriously and that there is nothing biologically untoward or incoherent or wrong in assuming that sometimes, rarely but sometimes, novelties arise “without any clear connections to existing traits and structures.” And what better place to look for a discontinuity than in in language?

Let me end by adding two useful principles for future thinking on topics related to language and the mind:

1.     Chomsky is never (stupidly) wrong

2.     If you think that Chomsky is (stupidly) wrong go back to 1

2 comments:

  1. Frankly, did you read this news item (which talks about the actual paper) to the end? The syrinx is all cartilage and even softer tissue, so its presence or absence cannot be determined in anything between crown-group birds and crown-group crocodiles. There are some 170 million years between the first members of these and their last common ancestor. If Tyrannosaurus or Diplodocus – closer to the birds than the crocodiles are, the former more so than the latter – had some surprising precursor version of a syrinx, we're not likely going to find out anytime soon.

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    1. To be honest, what interested me was not the fact of the matter concerning the syrinx (a point I made in the paragraph headed by "Is all this correct?") but the fact that biologists did not find it illegitimate to speculate that the syrinx was indeed novel. That bothered them not a jot. There was no presupposition that this was an out of bounds position. Rather they seem to think that the claim stood or fell on the evidence concerning the claim itself. This is NOT what we find in the language domain, where it is presupposed that a non-continuous conception of the mergence of linguistic facility is in virtue of being non-continuous rendered illegitimate. Biologists don't buy this.

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