[dinosaur] Mammals and birds from Eocene of Antarctica + barbourofelines are nimravids
Ben Creisler <[email protected]> Thu, 9 Jan 2020 08:29:08 -0800
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--000000000000f66212059bb78215 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: Quoted-printable Ben [email protected]=0A=0ASome Cenozoic items that may be of = interest:=0A=0ASarah N. Davis, Christopher R. Torres, Grace M. Musser, Jame= s V. Proffitt,=0ANicholas M.A. Crouch, Ernest L. Lundelius, Matthew C. Lama= nna & Julia A.=0AClarke (2020)=0ANew mammalian and avian records from the l= ate Eocene La Meseta and=0ASubmeseta formations of Seymour Island, Antarcti= ca.=0APeerJ 8:e8268=0Adoi: https://urldefense.proofpoint.com/v2/url?u=3Dhtt= ps-3A__doi.org_10.7717_peerj.8268&d=3DDwIFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOU= HhpN0H8p7CSfnc_gI&r=3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_X= DiApM6Y1zFnHp-c4JipeeNhYR8UG9YGHO8BRKQ&s=3DFh8gVeHHp-qeAo0JGgrgFM9e-Q9uDUOO= iewkmd30ZTk&e=3D=20=0Ahttps://urldefense.proofpoint.com/v2/url?u=3Dhttps-3A= __peerj.com_articles_8268_&d=3DDwIFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8= p7CSfnc_gI&r=3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiApM6Y= 1zFnHp-c4JipeeNhYR8UG9YGHO8BRKQ&s=3DaExK2TRMhMLilresSjV58S-0mW3pYEk_lJRA0BJ= wMu8&e=3D=20=0A=0AFree pdf:=0Ahttps://urldefense.proofpoint.com/v2/url?u=3D= https-3A__peerj.com_articles_8268.pdf&d=3DDwIFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU= 5BOUHhpN0H8p7CSfnc_gI&r=3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3Dh= Gd_XDiApM6Y1zFnHp-c4JipeeNhYR8UG9YGHO8BRKQ&s=3DWR1M0khpAnMIYzBmOga2x_FARpou= fOgOA5PhxvZom-s&e=3D=20=0A=0AThe middle=E2=80=93late Eocene of Antarctica w= as characterized by dramatic change=0Aas the continent became isolated from= the other southern landmasses and the=0AAntarctic Circumpolar Current form= ed. These events were crucial to the=0Aformation of the permanent Antarctic= ice cap, affecting both regional and=0Aglobal climate change. Our best ins= ight into how life in the high latitudes=0Aresponded to this climatic shift= is provided by the fossil record from=0ASeymour Island, near the eastern c= oast of the Antarctic Peninsula. While=0Aextensive collections have been ma= de from the La Meseta and Submeseta=0Aformations of this island, few avian = taxa other than penguins have been=0Adescribed and mammalian postcranial re= mains have been scarce. Here, we=0Areport new fossils from Seymour Island c= ollected by the Antarctic Peninsula=0APaleontology Project. These include a= mammalian metapodial referred to=0AXenarthra and avian material including = a partial tarsometatarsus referred=0Ato Gruiformes (cranes, rails, and alli= es). Penguin fossils=0A(Sphenisciformes) continue to be most abundant in ne= w collections from=0Athese deposits. We report several penguin remains incl= uding a large=0Aspear-like mandible preserving the symphysis, a nearly comp= lete=0Atarsometatarsus with similarities to the large penguin clade Palaeeu= dyptes=0Abut possibly representing a new species, and two small partial=0At= arsometatarsi belonging to the genus Delphinornis. These findings expand=0A= our view of Eocene vertebrate faunas on Antarctica. Specifically, the new= =0Aremains referred to Gruiformes and Xenarthra provide support for previou= sly=0Aproposed, but contentious, earliest occurrence records of these clade= s on=0Athe continent.=0A=0A=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=0A=0AOriens= milus liupanensis gen. and sp. nov.=0A=0AXiaoming Wang, Stuart C. White & J= ian Guan (2020)=0AA new genus and species of sabretooth, Oriensmilus liupan= ensis=0A(Barbourofelinae, Nimravidae, Carnivora), from the middle Miocene o= f China=0Asuggests barbourofelines are nimravids, not felids.=0AJournal of = Systematic Palaeontology (advance online publication)=0Adoi: https://urldef= ense.proofpoint.com/v2/url?u=3Dhttps-3A__doi.org_10.1080_14772019.2019.1691= 066&d=3DDwIFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=3DRy_mO4IF= aUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiApM6Y1zFnHp-c4JipeeNhYR8UG9Y= GHO8BRKQ&s=3DM7JlEwx5fp1RRceiwGwFGcI_MFApnp-tc9UAaZIP7RQ&e=3D=20=0Ahttps://= urldefense.proofpoint.com/v2/url?u=3Dhttps-3A__www.tandfonline.com_doi_full= _10.1080_14772019.2019.1691066&d=3DDwIFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhp= N0H8p7CSfnc_gI&r=3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiA= pM6Y1zFnHp-c4JipeeNhYR8UG9YGHO8BRKQ&s=3DJgL6td_kxJPp6UOZ28Yk-mNIg6ANW4zrbn4= 48N-z3-E&e=3D=20=0A=0A=0ASince the early 2000s, a revival of a felid relati= onship for barbourofeline=0Asabretooths has become popular due to recent di= scoveries of fragmentary=0Afossils from Africa. According to this view, bar= bourofelines trace their=0Acommon ancestor with felids through shared simil= arities in dental=0Amorphology going back to the early Miocene of Africa an= d Europe. However,=0Awhether or not such an idea is represented in the basi= cranial morphology, a=0Aconservative area of high importance in family-leve= l relationships, is yet=0Ato be tested. A nearly complete skull of Oriensmi= lus liupanensis gen. and=0Asp. nov. from the middle Miocene Tongxin Basin o= f northern China represents=0Athe most primitive known barbourofeline with = an intact basicranial region,=0Aaffording an opportunity to re-examine the = relationship of felids and=0Animravines. We also present an update on East = Asian records of=0Abarbourofelines. The new skull of Oriensmilus possesses = a suite of=0Acharacters shared with nimravines, such as the lack of an ossi= fied=0A(entotympanic) bullar floor, absence of an intrabullar septum, lack = of a=0Aventral promontorial process of the petrosal, presence of a small ro= stral=0Aentotympanic on the dorsal side of the caudal entotympanic, and a d= istinct=0Acaudal entry of the internal carotid artery and nerve that pierce= s the=0Acaudal entotympanic at the junction of the ossified and unossified = caudal=0Aentotympanics. The absence of an ossified bullar floor in O. liupa= nensis=0Aand its presence in those from the middle Miocene of Sansan, Franc= e thus=0Ahelp to bracket the transition of this character, which must have = happened=0Ain the early part of the middle Miocene. Spatial relationships b= etween=0Abullar construction and the middle ear configuration of the caroti= d artery=0Ain Oriensmilus strongly resemble those in nimravines but are dis= tinctly=0Adifferent from felids and other basal feliforms. Despite the attr= active=0Anotion that early barbourofelines arose from a Miocene ancestor th= at also=0Agave rise to felids, the basicranial evidence argues against this= view.=0A=0Ahttps://urldefense.proofpoint.com/v2/url?u=3Dhttp-3A__zoobank.o= rg_urn-3Ahttp-3A__lsid-3Azoobank.org-3Apub-3A2DE98DBC-2D4D02-2D4E18-2D9788-= 2D0B0D8587E73F&d=3DDwIFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r= =3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiApM6Y1zFnHp-c4Jip= eeNhYR8UG9YGHO8BRKQ&s=3DJY0ww2rbhOq-jwteDUFA7xJbBOioEmS5s6DmEi8sZpQ&e=3D=20= =0A= --000000000000f66212059bb78215 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: Quoted-printable <div dir=3D"ltr"><div><br></div>Ben Creisler<div><a href=3D"mailto:bcreisle= [email protected]">[email protected]</a></div><div><br></div><div>Some Cenozoic= items that may be of interest:<br><div><br></div><div>Sarah N. Davis, Chri= stopher R. Torres, Grace M. Musser, James V. Proffitt, Nicholas M.A. Crouch= , Ernest L. Lundelius, Matthew C. Lamanna & Julia A. Clarke (2020)<br>N= ew mammalian and avian records from the late Eocene La Meseta and Submeseta= formations of Seymour Island, Antarctica. <br>PeerJ 8:e8268<br>doi: <a hre= f=3D"https://urldefense.proofpoint.com/v2/url?u=3Dhttps-3A__doi.org_10.7717= _peerj.8268&d=3DDwMFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc= _gI&r=3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiApM6= Y1zFnHp-c4JipeeNhYR8UG9YGHO8BRKQ&s=3DFh8gVeHHp-qeAo0JGgrgFM9e-Q9uDUOOie= wkmd30ZTk&e=3D">https://doi.org/10.7717/peerj.8268</a><br><a href=3D"ht= tps://urldefense.proofpoint.com/v2/url?u=3Dhttps-3A__peerj.com_articles_826= 8_&d=3DDwMFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r= =3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiApM6Y1zFnHp-c= 4JipeeNhYR8UG9YGHO8BRKQ&s=3DaExK2TRMhMLilresSjV58S-0mW3pYEk_lJRA0BJwMu8= &e=3D">https://peerj.com/articles/8268/</a></div><div><br>Free pdf:<br>= <a href=3D"https://urldefense.proofpoint.com/v2/url?u=3Dhttps-3A__peerj.com= _articles_8268.pdf&d=3DDwMFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8= p7CSfnc_gI&r=3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_= XDiApM6Y1zFnHp-c4JipeeNhYR8UG9YGHO8BRKQ&s=3DWR1M0khpAnMIYzBmOga2x_FARpo= ufOgOA5PhxvZom-s&e=3D">https://peerj.com/articles/8268.pdf</a><br><br>T= he middle=E2=80=93late Eocene of Antarctica was characterized by dramatic c= hange as the continent became isolated from the other southern landmasses a= nd the Antarctic Circumpolar Current formed. These events were crucial to t= he formation of the permanent Antarctic ice cap, affecting both regional an= d global climate change. Our best insight into how life in the high latitud= es responded to this climatic shift is provided by the fossil record from S= eymour Island, near the eastern coast of the Antarctic Peninsula. While ext= ensive collections have been made from the La Meseta and Submeseta formatio= ns of this island, few avian taxa other than penguins have been described a= nd mammalian postcranial remains have been scarce. Here, we report new foss= ils from Seymour Island collected by the Antarctic Peninsula Paleontology P= roject. These include a mammalian metapodial referred to Xenarthra and avia= n material including a partial tarsometatarsus referred to Gruiformes (cran= es, rails, and allies). Penguin fossils (Sphenisciformes) continue to be mo= st abundant in new collections from these deposits. We report several pengu= in remains including a large spear-like mandible preserving the symphysis, = a nearly complete tarsometatarsus with similarities to the large penguin cl= ade Palaeeudyptes but possibly representing a new species, and two small pa= rtial tarsometatarsi belonging to the genus Delphinornis. These findings ex= pand our view of Eocene vertebrate faunas on Antarctica. Specifically, the = new remains referred to Gruiformes and Xenarthra provide support for previo= usly proposed, but contentious, earliest occurrence records of these clades= on the continent.</div><div><br>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<br></= div></div><div><br></div><div>Oriensmilus liupanensis gen. and sp. nov.</di= v><div><br>Xiaoming Wang, Stuart C. White & Jian Guan (2020)<br>A new g= enus and species of sabretooth, Oriensmilus liupanensis (Barbourofelinae, N= imravidae, Carnivora), from the middle Miocene of China suggests barbourofe= lines are nimravids, not felids.<br>Journal of Systematic Palaeontology (ad= vance online publication)<br>doi: <a href=3D"https://urldefense.proofpoint.= com/v2/url?u=3Dhttps-3A__doi.org_10.1080_14772019.2019.1691066&d=3DDwMF= aQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=3DRy_mO4IFaUmG= of_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiApM6Y1zFnHp-c4JipeeNhYR8UG9Y= GHO8BRKQ&s=3DM7JlEwx5fp1RRceiwGwFGcI_MFApnp-tc9UAaZIP7RQ&e=3D">http= s://doi.org/10.1080/14772019.2019.1691066</a> <br><a href=3D"https://urldef= ense.proofpoint.com/v2/url?u=3Dhttps-3A__www.tandfonline.com_doi_full_10.10= 80_14772019.2019.1691066&d=3DDwMFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUH= hpN0H8p7CSfnc_gI&r=3DRy_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m= =3DhGd_XDiApM6Y1zFnHp-c4JipeeNhYR8UG9YGHO8BRKQ&s=3DJgL6td_kxJPp6UOZ28Yk= -mNIg6ANW4zrbn448N-z3-E&e=3D">https://www.tandfonline.com/doi/full/10.1= 080/14772019.2019.1691066</a><br><br><br>Since the early 2000s, a revival o= f a felid relationship for barbourofeline sabretooths has become popular du= e to recent discoveries of fragmentary fossils from Africa. According to th= is view, barbourofelines trace their common ancestor with felids through sh= ared similarities in dental morphology going back to the early Miocene of A= frica and Europe. However, whether or not such an idea is represented in th= e basicranial morphology, a conservative area of high importance in family-= level relationships, is yet to be tested. A nearly complete skull of Oriens= milus liupanensis gen. and sp. nov. from the middle Miocene Tongxin Basin o= f northern China represents the most primitive known barbourofeline with an= intact basicranial region, affording an opportunity to re-examine the rela= tionship of felids and nimravines. We also present an update on East Asian = records of barbourofelines. The new skull of Oriensmilus possesses a suite = of characters shared with nimravines, such as the lack of an ossified (ento= tympanic) bullar floor, absence of an intrabullar septum, lack of a ventral= promontorial process of the petrosal, presence of a small rostral entotymp= anic on the dorsal side of the caudal entotympanic, and a distinct caudal e= ntry of the internal carotid artery and nerve that pierces the caudal entot= ympanic at the junction of the ossified and unossified caudal entotympanics= . The absence of an ossified bullar floor in O. liupanensis and its presenc= e in those from the middle Miocene of Sansan, France thus help to bracket t= he transition of this character, which must have happened in the early part= of the middle Miocene. Spatial relationships between bullar construction a= nd the middle ear configuration of the carotid artery in Oriensmilus strong= ly resemble those in nimravines but are distinctly different from felids an= d other basal feliforms. Despite the attractive notion that early barbourof= elines arose from a Miocene ancestor that also gave rise to felids, the bas= icranial evidence argues against this view.<br><br><a href=3D"https://urlde= fense.proofpoint.com/v2/url?u=3Dhttp-3A__zoobank.org_urn-3Ahttp-3A__lsid-3A= zoobank.org-3Apub-3A2DE98DBC-2D4D02-2D4E18-2D9788-2D0B0D8587E73F&d=3DDw= MFaQ&c=3DclK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=3DRy_mO4IFaU= mGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=3DhGd_XDiApM6Y1zFnHp-c4JipeeNhYR8UG= 9YGHO8BRKQ&s=3DJY0ww2rbhOq-jwteDUFA7xJbBOioEmS5s6DmEi8sZpQ&e=3D">ht= tp://zoobank.org/urn:http://lsid:zoobank.org:pub:2DE98DBC-4D02-4E18-9788-0B= 0D8587E73F</a><br><br></div></div>=0A= --000000000000f66212059bb78215--