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Any developmental biologist care to comment on this? Something about this #arxiv  paper doesn't seem quite right...
#evodevo   #evolutionarybiology   #developmentalbiology  
Abstract: An intriguing unanswered question about the evolution of bilateral animals with internal skeletons is how an internal skeleton evolved in the first place. Computational modeling of the devel...
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Susan Steckov's profile photoTommy Leung's profile photoMary Mangan's profile photoPZ Myers's profile photo
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Yeah...I didn't read it, my skeletal development is rusty. But even the abstract didn't make sense to me. If a mutation enabled the inversion, why is the new orientation inherited epigenetically?

Given the development of two bilateral founder cells that generate a bilateral organism, a mutation that reverses the internal mirror orientation of those bilateral founder cells leads to inside-out development. The new orientation is epigenetically inherited by all progeny.

This makes my head hurt.
 
Never mind what the paper suggests seems to be unsupported by the fossil record, it is also really thin (8 pages - in pre-print format), and 3 references - all #arxiv  papers and all by the author himself.

It has a Donald Williamson of the "Butterfly + velvet worm = caterpillar" feel to it...with even less biology...
 
Genetic reversal is possible, by changing the axis, however, I do not see in the abstract where the species was named.  A bit of a flag....inferred by "exoskeleton" is perhaps an insect - some of which are microscopic.  But I have to agree with Tommy L.  Even the procedure for a simple organism could not be covered in 8 pages.  Although, he refers to the imaginal discs contained in the caterpillar that store the information to create the mature butterfly.....I cannot see how this process could be reversed.
 
Try to get PZ's attention on that.
 
While I suspect +PZ Myers might be a bit busy to look into this, I've just tagged him here in case he is interested...
 
Interesting...although I don't see why you have to propose turning the organism inside out. Flipping the polarity of the inductive signal seems more economical and likely.
 
I can't claim much knowledge regarding developmental biology. The thing that really struck me about the paper was how sparse it was in terms of biology and absence of any references to the existing body of work in this field. The author seems...naive about biology? 
 
Wait, no. Insects use a different tissue altogether to form an exoskeleton; they aren't in any way homologous. I just read the paper and it makes no sense at all, because they seem to be ignoring the actual biology of the organisms involved.
 
Yes, it all seems quite peculiar, hence as I said before, the author seems rather naive about biology...actually I'll correct that statement - the author seems hopelessly ignorant about biology.
 
Yeah, the homology between vertebrate and arthropod ectoderm, for instance, is pretty solid. It doesn't even work to say one is an invert of the other: the vertebrate skeleton is mesodermally derived, while the arthropod exoskeleton is ectodermally derived. And both groups generate mesoderm in similar ways, by involution/ingression during gastrulation.

We also have organisms that have internal skeletons in larval forms and ectoskeletons as adults -- echinoderms. They don't turn inside out at metamorphosis.
 
There's a big push among the genomics peeps to get stuff on to ArXiv. I hope it won't get abused by bio cranks and make it less appealing. Is that a problem for communities already using it?
 
I actually put up a post about it -- the closer I looked, the more irritated I got. He got help from Francis Hitching? Jebus.
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