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Re: [dinosaur] Pterosaurs tracks from Spain + ameghinornithid-like bird from China + bird claw shape + tetrapod hearing + more

> A revised version of a paper first posted back in 2015:
> Free pdf:
> David Marjanović​ and Michel Laurin (2016)
> Reevaluation of the largest published morphological data matrix for 
> phylogenetic analysis of Paleozoic limbed vertebrates.
> PeerJ Preprints 4:e1596v2
> doi: 
> https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.7287_peerj.preprints.1596v2&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=MbBBB8Tibwen5ymvbOyJrQwPyWeyHz0PbWNSiE_8M6g&s=sEmq63wnujxhbf7Z_dEw-Bv6Q2B-dHiaLx9IuVAuQRI&e=

Thank you. :-)

> New book that may be of interest:
> Jennifer A. Clack, Richard R Fay & Arthur N. Popper (eds.) (2016)
> Evolution of the Vertebrate Ear: Evidence from the Fossil Record.
> Springer Handbook of Auditory Research 59 2016
> ISBN: 978-3-319-46659-0 (Print) 978-3-319-46661-3 (Online)
> DOI: 10.1007/978-3-319-46661-3
> https://urldefense.proofpoint.com/v2/url?u=http-3A__link.springer.com_book_10.1007_978-2D3-2D319-2D46661-2D3&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=MbBBB8Tibwen5ymvbOyJrQwPyWeyHz0PbWNSiE_8M6g&s=Ec9eBlRgpxonhWSUYHCVeRwnBItaiSh8JU0sXjZ5GjY&e=

Oh, great. :-) Now I need access to a Springer book (Springer = seriously 
expensive) before I can publish on this topic, and my institution's retired 
librarian hasn't been replaced so far.

> Rainer R. Schoch and Jason S. Anderson (2016)
> Amphibia: A Case of Diversity and Convergence in the Auditory Region.
> The Ear of Mammals: From Monotremes to Humans.
> Evolution of the Vertebrate Ear: Evidence from the Fossil Record. 
> Springer Handbook of Auditory Research 59:  327-355
> DOI: 10.1007/978-3-319-46661-3_11
> https://urldefense.proofpoint.com/v2/url?u=http-3A__link.springer.com_chapter_10.1007_978-2D3-2D319-2D46661-2D3-5F11&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=MbBBB8Tibwen5ymvbOyJrQwPyWeyHz0PbWNSiE_8M6g&s=avIiLSFpvPyaS1o6Fl8J_o1aHCW4L0lWHOWqUIf7lc4&e=
> The ears of extant amphibians are remarkably diverse and when fossil taxa are 
> considered, the picture becomes even more complicated. Anurans have a 
> differentiated stapes inside a middle ear cavity associated with a eustachian 
> tube and tympanum. Instead, salamanders and caecilians have rudimentary 
> stapes connected to the cheek or jaw articulation, and they lack the tympanum 
> and middle ear cavity. At the same time, batrachians (salamanders and frogs) 
> share a second ear ossicle, the batrachian operculum, whereas all 
> lissamphibians have a second receptor in the inner ear, the amphibian 
> papilla. The largest fossil clade and probable stem group of Lissamphibia, 
> the temnospondyls, had a stapes similar to that of anurans, consistent in the 
> possession of a ventral process and an elongate and slender distal shaft that 
> probably attached to a tympanum. The evolutionary sequence of ear types forms 
> a puzzle with several of the major groups each sharing features that others 
> lack. The primitive condition is exemplified by the temnospondyl ear, 
> especially that of dissorophoids. We argue that the loss of the tympanic 
> system was an evolutionary option only available after the batrachian 
> operculum had evolved.

Why would the operculum evolve when a tympanic ear was already present...?

On temnospondyls having frog-like stapedes, that is exclusively true for 
dissoroph_id_s, i.e. ?*Broiliellus reiszi* and rumors of one more. The closest 
relatives of Lissamphibia within the temnospondyl hypothesis are supposed to be 
the amphibamids, not the dissorophids, and what's been published of amphibamid 
stapedes (i.e. *Doleserpeton*) looks more like in other temnospondyls, where 
the stapes is a plank or club the size of the paroccipital process. In large 
temnospondyls like *Edops* or *Mastodonsaurus* this means the stapes is the 
size – length and diameter – of a human finger, and at least sometimes 
(*Mastodonsaurus*, *Stanocephalosaurus*) it forms a deeply interdigitated 
suture with the parasphenoid, rendering it immobile; it's not surprising that 
these thoroughly aquatic animals were deaf to high-frequency airborne sound, 
but the trematopid dissoroph_oid_ *Fedexia* has a stapes that is proportionally 
no smaller and likely immobile as well, "even though" it was most likely 

Consider also the phylogenetic position of the frogs within Lissamphibia: 
they're as highly nested as possible. Three separate losses of the middle ear 
would be required in salamanders, albanerpetids and caecilians if the middle 
ears of frogs and dissorophids (ignoring amphibamids) are to be homologous, 
unless we manage to stuff a lot of dissorophoids _into_ Lissamphibia, which 
doesn't look easy at the moment.

Finally, the eustachian tube + middle-ear cavity of frogs doesn't seem to be 
homologous to the spiracle at all. It begins to form (as an outgrowth from the 
throat cavity) during metamorphosis, well after the gill slits – of which the 
spiracle would be one – have come and gone. A paper describing this came out in 
a major journal in 1987.