Dyke et al. 2013 Put Microraptor In The Windtunnel… Badly

Dyke et al. have put a Microraptor into the wind tunnel:
http://www.nature.com/ncomms/2013/130918/ncomms3489/full/ncomms3489.html
Nothing good could come of this, one immediately suspects, but let’s suspend our cynicism for a moment. In some ways I’m pleased, since some don’t think Microraptor flew at all; also, in my book I’d invited people to experiment with a style of use of the hind wings I’d advocated there. But, you might say, surely they didn’t actually investigate my model, did they? (Check my earlier post)

Well… they didn’t “ignore” it as much as you’d expect. My model has the toes pointing out sideways… which means the knees tend to point somewhat sideways but basically up. The leg has to bend downwards at the knee since dinobird knees apparently couldn’t straighten (according to Greg Paul, and no-one seems to disagree).

Greg wasn't sure about this config. originally.

Greg wasn’t sure about this config. originally.


Not many people have the rear wings like that. I can’t think of anyone who did before me; I may be wrong, but in any case, their pose, below, is a bit like the “toes-out” pose I advocate in my book, and unlike the other poses, I couldn’t think of anyone else to name it after, when I released the book last summer.

Not Toeing The Line

But Dyke et al. have the down-bend at the knee… but with the toes pointing forwards!
dykesmicro01
How?? Dinobirds like this have ankles that can only bend like simple hinges, and although whatever your configuration, people will say “Ooh! It couldn’t possibly bend/twist like that!”, the Dyke et al. one is truly inexplicable. Surely the dinobird specialists on the author list would know that. What were they doing, the day the model got made??!

But then Why?? Why depart from what the front wings are doing – digits and primaries pointing sideways and slightly back?! You might say it’s because the model has to have a hinge there, to investigate different angles, but any such hinge wouldn’t need to have the foot section of the wing displaced sharply forward of the rest of the wing, as they have it. Indeed, forward is bad, rearward is good, to help support the weight of the tail. And again, as ever, I am still the only person to mention the need for the rear wing to support the weight of the tail… and it’s still the case that anyone writing on the subject without even mentioning that need, cannot be taken seriously.

What Can We Learn From Their Model?

OK – so much for engineering. Now we ask: “What we can generalise about the real animal from an imperfect model?”

Very importantly, very little. The problem is, few palaeontologists understand the meaning of palaeontological experiments. Remember how it was claimed bumblebees couldn’t fly? That was because one (notional) model of bumblebee physics prohibited flight, but if the model is wrong, no valid conclusions may be drawn from it.

You can draw useful conclusions from a palaeontological experiment, if the model meaningfully generalises to the reality. And usually it’s more convincing to show an animal might be able do something if the model could, than to conclude an animal couldn’t do something because one flawed model couldn’t. Dyke co-authored a terrible paper a couple of years ago, claiming that Confuciusornis couldn’t fly, only glide. That time again, he tried to use an unjustifiable model, to suggest an ancient animal couldn’t do something. And Confuciusornis, with huge wings with gigantically strong wingbones – and huge feathers – is found fossilised in flocks, in the middle of a lake. What a gliding animal without powered flight is doing in flocks at all, I’m not sure, and for a ‘gliding’ flock to be over the middle of a lake would be even more impossible. Also, there are no ecologically important gliders today amongst insects, few if any amongst vertebrates, and certainly no top aerial predators. And if Confuciusornis and Microraptor glided but lacked powered flight, why did they never evolve it, over 20 million years after Archaeopteryx?!

Dyke’s biology is as hopeless as his engineering and his philosophy of science, which is where his ungeneralisability error lies. I seem to remember the job he got in the USA (AMNH) a few years ago was advertised as requiring someone well-grounded in Ph. of Sci. “Huh” to that. I do like the bent-knees-out style of the model, and the experiments seemed fine on the models they were given, but no conclusion on Microraptor the authors tried to extract from them, and none of their conclusions on the origin of flight were valid, and should not be mistaken for science.

Summary and added points

1: Unjustifiable generalisation from dubious model to real animal, without the stated admission that the generalisation could only be as good as the model. This is an example where getting your philosophy of science wrong makes the whole project a waste of time.

2: Experimental results of ‘Couldn’t’, instead of a more reasonable ‘Might have’. If your experiment concludes ‘Couldn’t’, then be reluctant to publish, unless the generalisation is thoroughly convincing. Another example of bad philosophy of science.

3: Dead weird ankle angle and resultant foot feather positioning.

4: Inexplicable assumption that an aeronaut animal would be incapable of adjusting trim in flight. Totally invalidates the main messages of the paper.

5: But nice to see front wings of any vodrom such as Microraptor apparently designed and suitable for aeronauting for a change, and nice to see the design of the whole back wing at least as far as the foot.

6: Accepting as given that the creature lacked powered flight. Some modern flying birds, even large ones, don’t glide much. If the main flight mode was flapping, perhaps even four-wing flapping, that again makes the project meaningless. And the idea that a design of predator with feathered front wings like that could thrive and remain dominant for 80 million years or even 20, without evolving powered flight, utterly beggars belief.

7. Total failure to acknowledge the Conjecture and Refutation nature of science; in particular, the total failure to list all the feasible theories and eliminate as many as possible, as fairly as possible. As is usually the case when members of the Society of Vertebrate Paleontology venture amongst dinobirds, they violate Ж:10 of Sciencepolice-14 Rules, in this case especially the third and particularly the last sentence:

10) Evidence is those observations not well explained by a theory, or not as well explained by one theory as by another.
Positive but non-comparative evidence (explained by a theory), though useful in the black art of theory generation, merely progresses testing.
‘Positive evidence’ must not be trumpeted as ‘evidence for’ a theory when competing theories also explain it.
Papers and journals should ensure the full landscape and pattern of posable theories are reasonably accounted for
.

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