Hynerpeton

Hynerpeton / / h aɪ ˈnɜːr pətɒn / lit.​​lit. Dabbobin   ) wani bacewa ne na farkon kashin baya mai kafa hudu wanda ya rayu a cikin koguna da tafkunan Pennsylvania a lokacin Late Devonian, kusan shekaru miliyan 365, zuwa 363, da suka gabata. Abin sani kawai nau'in Hynerpeton shine H. bassetti, mai suna bayan kakan mai kwatanta, mai tsara birni Edward Bassett . An san Hynerpeton da kasancewa na farko na Devonian kashin baya mai kafa huɗu da aka gano a Amurka, da kuma yuwuwar kasancewa ɗaya daga cikin na farko da suka yi hasara na ciki (kamar kifi) .

An san wannan nau'in daga 'yan ragowar da aka gano a rukunin burbushin Red Hill a Hyner, Pennsylvania . Mafi shahararren burbushin halittu shine babban ginshikin kafada na endochondral wanda ya ƙunshi cleithrum, scapula, da coracoid (amma ba interclavicle da clavicles ), duk an haɗa su zuwa kashi ɗaya na kafada. saman ciki na wannan ƙashin kafada yana da tarin baƙin ciki da aka yi imani da cewa sun kasance abubuwan da aka makala don keɓaɓɓen saitin tsoka mai ƙarfi a kusa da ƙirji. Wannan na iya ba Hynerpeton ingantacciyar motsi da iya ɗaukar nauyi idan aka kwatanta da sauran ɓangarorin kashin baya na Devonian kamar Ichthyostega da Acanthostega . Cleithrum (babban ruwan kafada) an haɗa shi zuwa scapulocoracoid (ƙananan farantin kafada, a gaban soket ɗin kafada), sabanin yawancin tetrapods. Sabanin haka, abin wuyan kafada ya kasance mai zaman kansa daga kwanyar, sabanin yawancin kifi.

Ana kiran kashin bayan kafa huɗu na farko a matsayin tetrapods, bisa ga ma'anar ma'anar kalmar kamar yadda yawancin masana burbushin halittu ke amfani da su. Dabbobin Devonian kamar Hynerpeton, Ichthyostega, da Acanthostega an cire su daga rukunin kambin Tetrapoda, tunda sun samo asali ne tun kafin kakannin kakannin amphibians na zamani ( Lissamphibia ), dabbobi masu rarrafe, dabbobi masu shayarwa, da tsuntsaye . Ga kwararrun da suka gwammace ma'anar tetrapods na neontological (watau kawai a cikin mahallin rayuwar zamani), madadin sharuɗɗan tetrapods waɗanda ba kambi ba sun haɗa da " stem-tetrapod " ko " stegocephalian ".

Hynerpeton ya fito ne daga burbushin burbushin Red Hill, wanda, a lokacin Late Devonian, ya kasance filin ambaliyar ruwa mai ɗumi wanda ke tattare da yanayin yanayin kifin ruwa da kuma invertebrates na ƙasa. Hynerpeton yana daya daga cikin nau'ikan kasusuwa masu kafa hudu da aka sani daga wurin, ko da yake shi ne farkon da aka gano. Wasu masana burbushin halittu sun ba da shawarar cewa dabbobi kamar Hynerpeton sun yi amfani da salon rayuwarsu mai ban sha'awa don nemo wuraren tafkuna masu zurfi inda za su iya haifuwa, keɓe daga kifaye masu kifin da ke zaune a cikin koguna masu zurfi.

 Tarihi. 
A cikin 1993, masana burbushin halittu Edward "Ted" Daeschler da Neil Shubin sun gano burbushin Hynerpeton na farko a rukunin burbushin Red Hill kusa da Hyner, Pennsylvania, Amurka. Suna binciken duwatsun Devonian na Pennsylvania don neman shaidar burbushin halittu na asalin kasusuwan kasusuwa.   Wannan farkon ganowa wani ɗaurin kafaɗa mai ƙarfi na hagu na endochondral, mallakar wata dabba ce mai ƙarfi. Wannan burbushin, wanda aka zayyana ANSP 20053, yanzu ana la'akari da samfurin holotype na Hynerpeton, wanda Daeschler da abokan aikinsa suka sanya suna a ka'ida a cikin labarin da Mujallar Kimiyya ta buga a 1994. A lokacin da aka gano shi, Hynerpeton ita ce kashin bayanta mai kafa hudu mafi tsufa da aka sani daga Amurka, kuma kasancewarta a cikin wani hadadden tsarin halittu kamar wanda aka adana a Red Hill ya taimaka wajen amsa wasu tambayoyi na Daeschler da Shubin kan asali da salon rayuwa. kashin baya. Sunan gama gari Hynerpeton yana magana ne akan Hyner da herpeton ("dabba mai rarrafe"), kalmar Helenanci wacce aka saba amfani da ita azaman kari ga sabbin amfibiya masu suna. Sunan musamman, bassetti, ana kiransa don girmama Edward M. Bassett, mai tsara biranen Amurka da kakan Daeschler.  

Mafi girman burbushin burbushin rukunin yanar gizon Red Hill, " Lens Hynerpeton ", an sanya masa suna bayan jinsin halitta. An yi imanin an ajiye shi a lokacin Tsakiyar Tsakiya zuwa Babban Famennian, kimanin shekaru 365, zuwa 363, da suka wuce.  Tun daga 1993, an sami ƙarin ragowar stegocephalian a cikin ruwan tabarau na Hynerpeton (wanda kuma aka sani da Farwell paleosols ). Waɗannan sun haɗa da ƙasusuwan kafaɗa, ƙasusuwan muƙamuƙi, gutsuttsuran kwanyar, gastralia (scutes na ciki), femur, da kuma humerus babba da ba a saba gani ba.  A cikin 2000, an ba da kasusuwan kasusuwa guda biyu zuwa nau'i na biyu, Densignathus ,  da sauran nazarin sun yi jayayya cewa ƙarin ƙarin haraji da ba a san su ba sun kasance a wurin, ciki har da yiwuwar mafi tsufa da aka sani whatcheeriid . 

An sanya wasu daga cikin wannan kayan zuwa Hynerpeton, amma a yawancin lokuta, an mayar da waɗannan ayyukan. Misali, masanin burbushin halittu Jenny Clack ya yi nuni da wasu burbushin halittu masu yawa ga jinsin halittu a cikin bitarta ta 1997, na hanyoyin Devonian. Wadannan burbushin, wadanda ba a san su a baya ba a cikin wallafe-wallafen kimiyya, sun haɗa da jugal (ƙashin kunci), ɓangarorin ciki, da wani yanki na mandible (ƙananan muƙamuƙi).  A cikin 2000, Daeschler ya bayyana mandible (ANSP 20901) a cikin zurfin zurfi, kuma ya kwatanta shi da ragowar Densignathus .  Daeschler, Clack, da Shubin ne suka gudanar da ƙarin cikakken nazarin burbushin Red Hill " tetrapod " a cikin 2009. Sun lura cewa yawancin burbushin an sanya su zuwa Hynerpeton bisa kusancin da suke da shi har zuwa lokacin da aka gano ainihin abin ɗaurin kafada na endochondral. Duk da haka, sun yi jayayya cewa, tun da akwai wasu dabbobi na musamman (watau Densignathus, mai mallakar humerus, da whatcheerids ) kusa da wannan batu, kusanci bai isa ba don la'akari da waɗannan shawarwarin ingantacce. Saboda haka, ba su ɗauki ragowar da Clack (1997), da Daeschler (2000), suka bayyana a matsayin tabbacin misalan kayan Hynerpeton ba. Duk da haka, sun riƙe cleithrum na hagu da ake magana a kai, ANSP 20054, a cikin jinsin halittarsa saboda tsarinsa ya yi kama da na holotype. 

 Bayani. 
alt=|thumb|320x320px| Maidowa rayuwa mai hasashe ta Nobu Tamura
Mutane da yawa Hynerpeton sun kasance suna kama da sauran ɓangarorin kafa na farko ("tetrapods") kamar Ichthyostega ko Acanthostega . Ko da yake rashin isassun kayan burbushin halittu ya sa ba a kai ga cimma takamaiman matsaya game da halittar Hynerpeton ba, tsarin ginshiƙin kafaɗar endochondral da aka adana yana ba da wasu bayanai game da rarrabuwar sa. Ƙarƙashin kafaɗar endochondral shine ɓangaren kafada wanda ke dauke da scapula, coracoid, da cleithrum, amma ba clavicles da interclavicle . Gabaɗaya, ɗaurin kafaɗar endochondral yana da girma kuma yana da siffa . "Shaft" mai nuni zuwa sama yana samuwa ta cleithrum, wani kasusuwa mai kama da kashin kafada wanda yawancin amniotes suka rasa. An kafa "blade" na baya-bayan nan ta hanyar scapulocoracoid, wani nau'i mai kama da farantin karfe wanda kuma ya mallaki glenoid fossa ( soket na kafada ) tare da gefensa na baya kuma a baya tetrapods zai rabu cikin scapula da coracoid. A cikin kakannin kakannin kifi na lobe zuwa tetrapods, irin su Eusthenopteron, an haɗa ɗaurin kafadar endochondral zuwa kwanyar. A cikin tetrapods na gaskiya, ginshiƙin kafada na endochondral ya kasu kashi biyu daban-daban: cleithrum da scapulocoracoid. Hynerpeton yana tsaka-tsaki ne tsakanin waɗannan jihohi biyu, saboda an raba ɗaurin kafadar endochondral daga kwanyar amma har yanzu ba a raba kashi biyu ba. Ta wannan hanyar Hynerpeton yana kama da Devonian stem-tetrapods maimakon tetrapods na gaskiya, wanda bai bayyana a cikin tarihin burbushin halittu ba har sai Carboniferous .  Dangane da girman kashin, mutumin Hynerpeton wanda yake cikinsa yana da kimanin tsawon mita 0.7 (ƙafa 2.3). 

Sashin cleithrum yana da santsi, ba kamar cleithrum mai laushi na kifin tetrapodomorph ba. Bugu da ƙari, ɓangaren sama na cleithrum yana faɗaɗa kuma yana ɗan karkatar da gaba, wani hali da aka samo kama da Tulerpeton da tetrapods na gaskiya. Yankin scapulocoracoid yana da girma lokacin da aka gani daga gefe amma yana da bakin ciki sosai lokacin da aka gani daga ƙasa. Glenoid fossa ( soket na kafada) yana matsayi a kan gefen baya (na waje da na baya) na scapulocoracoid, matsayi mai mahimmanci fiye da sauran Tetrapods na Devonian (ban da Tulerpeton ). Sama da glenoid fossa wani yanki mai tasowa wanda aka sani da buttress supraglenoid. 

Har ila yau, Hynerpeton yana da autapomorphies da yawa, na musamman waɗanda babu wani sanannen tushe-tetrapod ya mallaka. Fuskar ciki na scapulocoracoid yana da babban ciki mai zurfi wanda aka sani da fossa subscapular. Babban bakin wannan bakin ciki yana da kyau sosai saboda an rufe shi da tabon tsoka. Gefen baya na fossa na subscapular, a gefe guda, an kafa shi ta wani babban yanki mai girma, wanda aka sani da buttress infraglenoid. Bacin rai na biyu da aka fi sani da infraglenoid fossa, wanda ke ci gaba da glenoid fossa, yana nannade bayan kashi don ya raba gindin infraglenoid. 

Waɗannan halayen da aka haɗa suna da alama suna goyan bayan ra'ayin cewa Hynerpeton yana da tsokoki masu ƙarfi da ke haɗe zuwa ɓangaren scapulocoracoid na ɗigon kafada na endochondral. Infraglenoid fossa ya sami haɓaka sosai a cikin wannan nau'in, kuma yana iya kasancewa tushen tushen tsokoki masu juyawa . Irin wannan tsagi a gefen gaba na kashi na iya taimakawa tare da ɗagawa ko tsawaita gaɓa. Gefen fossa na subscapular shima a fili ya ba da wuri don haɗin tsoka.  Kamar yadda ba a san waɗannan fasalulluka a cikin wasu kara-da kambi-tetrapods, da alama an yi amfani da musculature na Hynerpeton don wani nau'i na musamman, na gwaji wanda bai tsira daga Devonian ba.  Mawallafa na asali sun nuna cewa tsokoki masu ƙarfi na iya kasancewa daidai daidai da tafiya ko iyo. 

Ba kamar yawancin mutanen zamaninsa ba, Hynerpeton da alama ba shi da lamina bayan reshe . Wannan ruwan kasusuwa, wanda aka adana a cikin kifaye da yawa da kuma wasu kara-tetrapods ( Acanthostega, alal misali) ya kara tsayi tare da gefen ciki na cleithrum. Yawanci yana samar da bangon baya na ɗakin reshe (gill cavity), kuma mai yiwuwa ya taimaka wajen tabbatar da cewa ruwa yana gudana a hanya guda ta cikin gills . Rashinsa a Hynerpeton na iya nuna cewa ba shi da gills, kuma cewa zuriyar Hynerpeton na iya kasancewa daga cikin kashin baya na farko da suka haifar da wannan karbuwa.  Duk da haka, wannan fassarar ba tare da jayayya ba. Janis & Farmer (1999), ya lura cewa laminae na baya-bayan nan ba su nan a cikin wasu kifin eusthenopterid (wanda ke riƙe kasusuwan gill) kuma suna cikin Whatcheeria (wanda ba shi da wata shaida ga gills duk da ragowar da aka kiyaye).  Shoch & Witzmann (2011), lura cewa ba koyaushe ba ne a bayyane lokacin ko yadda ake adana laminae na postbranchial saboda bambance-bambancen ilimin halittar jiki na yawancin stegocephalian cleithra. Bugu da ƙari, sun nuna cewa salamanders na ruwa, wanda ke numfashi tare da gills na waje, ba sa buƙatar ko mallaki laminae na postbranchial.  Daeschler et al. (1994), yayi la'akari da asarar lamina na baya don zama siffa da aka samo asali wanda ke nuna cewa Hynerpeton ya fi "ci gaba" fiye da Acanthostega.  Sabanin haka, Schoch & Witzmann (2011), sun sami shaida ga lamina na baya-bayan nan a cikin kambi-tetrapods irin su temnospondyls Trematolestes da Plagiosuchus . Don haka, asarar Hynerpeton na lamina bayan reshe (da yuwuwar gills na ciki) mai yuwuwa ya samo asali ne daga kambi-tetrapods. 

 Rabewa. 
Asalin bayanin 1994, na Hynerpeton ya sanya shi cikin tsari na Ichthyostegalia na Tetrapoda superclass . A lokacin, "Tetrapoda" yana nufin duk wani kashin baya mai raɗaɗi huɗu da kuma "Ichthyostegalia" da ake kira "primitive", Ichthyostega - kamar 'yan Devonian na rukuni.  Koyaya, isowa da shaharar cladistics sun canza waɗannan sharuɗɗan biyu. Yawancin masana burbushin halittu suna ci gaba da amfani da ma'anar gargajiya ta "tetrapod"; 'yan kaɗan sun zaɓi ma'anar cladistic wanda ke taƙaita kalmar zuwa rukunin rawanin, clade (ƙungiya mai alaƙa), wanda ke ɗauke da zuriyar kakannin kakanni na ƙarshe na tetrapods masu rai.  Yayin da Hynerpeton tetrapod ne a ma’anar cewa kashin baya ne mai kafa hudu, ba memba ne na rukunin rawanin tetrapod ba, saboda zuriyarsa ta shude tun kafin zuriyar tetrapods ta zamani ta samo asali.  Hakazalika, "Ichthyostegalia" an yi watsi da shi a cikin shekarun cladistics saboda kasancewarsa matakin juyin halitta wanda ke kaiwa ga tetrapods na gaskiya, maimakon clade na tushen dangantaka.  Gargajiya ta gargajiya, wacce ba ta al'ada ta tetrapoda, wanda ya fara a farkon reshe na farko, yana da daidai da wata dangantakar mai suna Stegacefali, wanda aka ayyana shi kamar yadda duk dabbobi suka danganta da temnpondyls fiye da zubar da su . 

Hynerpeton ba a haɗa shi cikin yawancin nazarin halittu ba saboda ƙayyadadden adadin kayan burbushin sa. Wadancan nazarin da suka haɗa da shi yawanci suna sanya shi azaman tsaka-tsakin tsari akan jerin kara-tetrapods wanda ke haifar da kambi-Tetrapoda. Siffar cleithrum da asarar lamina na postbranchial sun ba da damar a sanya shi sama da Acanthostega (kuma yawanci Ichthyostega ma), amma riƙe da ɗaurin kafaɗa na endochondral guda ɗaya yana nufin cewa ba a sanya shi sama da Tulerpeton ba. Mai zuwa shine cladogram mai sauƙi wanda ya dogara akan Ruta, Jeffery, & Coates (2003): 

 Ilimin nazarin halittu. 
An samo Hynerpeton a Red Hill site na Pennsylvania. Wannan hanyar ta adana burbushin halittu daga ɗan Duncannon na Catskill Formation, wanda aka shimfiɗa a cikin wani tsohon filin ruwa na bakin teku. A lokacin marigayi Devonian, ambaliyar ruwa ta kasance kusa da ma'aunin ruwa, don haka yanayin ya kasance dumi da danshi, tare da lokacin bushewa da damina. Ya samo asali ne a bakin tekun wani ruwa mara zurfi wanda ya mamaye nahiyar Euramerica, kuma ya mamaye wasu kananan koguna masu jinkirin gudana daga tsaunukan Acadian a gabashin nahiyar. Waɗannan kogunan sun kasance masu saurin canza tafarkinsu sosai, suna ƙirƙirar tafkunan oxbow da tafkunan da ke kusa da manyan tashoshi na kogin. Mafi yawan tsire-tsire su ne gandun daji na tsoffin bishiyoyi masu girma ( Archaeopteris ) wanda aka cika da marshes cike da tsire-tsire masu kama da fern ( Rhacophyton ). Gobarar daji ta zama ruwan dare a lokacin rani, kamar yadda aka tabbatar da yawan adadin kayan Rhacophyton da aka kone. Sauran tsire-tsire sun haɗa da lycopsides irin su Lepidodendropsis da Otzinachsonia, da kuma ganyaye masu wuyar wuri da shrubs irin su Barinophyton da Gillespiea . 

Rayuwar dabba ta Red Hill ta kasance iri-iri. Early arachnids ( Gigantocharinus ), millipedes ( Orsadesmus ), da kunamai da ba a bayyana ba sun kasance daga cikin 'yan tsirarun mambobi na duniya na Red Hill fauna. Magudanar ruwa sun kasance da manyan kifaye iri-iri. Placoderms na Benthic irin su Phyllolepis na yau da kullun, Groenlandaspis na gama gari, da wadataccen Turriaspis sun kasance babban ɓangare na taron kifin. Kifin Limnomis na farko mai haske yana da yawa, mai yiwuwa ya kafa manyan makarantu. Sharks na farko sun kasance, gami da minuscule Ageleodus da Ctenacanthus mai kashin kashin baya. Kifi daban-daban da aka yi da lobe sun cika filin ambaliya, da kuma babban acanthodian Gyracanthus . Babban mafarin taron shine Hyneria, kifin tetrapodomorph mai tsayin mita 3, (ƙafa 10). 

Hynerpeton ba shine kawai ake zargin tetrapod a wurin ba. Wani ɗan ƙaramin girma, Densignathus, ya kasance tare da shi.   Bugu da kari, wani sabon humerus wanda bai dace da ginshikin kafadar endochondral na Hynerpeton na iya nuna cewa jinsi na uku ya rayu a cikin ambaliyar ruwa.  Gutsutsun kwanyar kwatankwacin irin na whatcheeriids irin su Pederpes da Whatcheeria na iya nuna cewa jinsi na huɗu ma yana nan,  ko da yake an tambayi abin da suke magana game da whatcheeriids.  Wurin da aka ba da izini da namun daji na rukunin Red Hill sun ba da sabbin hasashe don tambayoyin kan me yasa da yadda ƙasa ta samo asali a cikin kara-tetrapods. Rikicin Catskill bai taɓa bushewa ba don magudanan ruwansa su bushe gaba ɗaya, amma a wasu lokuta na shekara tafkuna masu zurfi sun zama keɓanta daga manyan tasoshin kogin. Dabbobin ƙasa ko na ruwa na iya amfani da waɗannan tafkuna a matsayin mafaka daga manyan kifayen da ke yin sintiri a magudanar ruwa.  Kwatankwacin zamani zai iya zama kogin Murray na Ostiraliya . A cikin wannan yanayi na zamani na zamani wanda ke fuskantar rigar da lokacin bushewa, spawning perch zinariya ( Macquaria ambigua ) ya fake a cikin tafkunan oxbow don tserewa mafi girma, murray cod ( Maccullochella peeli ) a cikin babban tashar kogin. A cikin yanayin Devonian, vertebrates masu iyawar ƙasa na iya samun fa'ida yayin kewayawa tsakanin waɗannan mahalli daban-daban. Sassaucin da irin wannan salon ya haifar zai iya ba su damar cin gajiyar manyan hanyoyin abinci iri-iri. 

 Duba kuma. 


 Ichthyostega.
 Acanthostega.

 Magana. 

 Hanyoyin haɗi na waje. 

 Hynerpeton a Devonian Times 
 Wanene a Red Hill (Devonian Times) 
 Shafin Hynerpeton (tare da hotunan burbushin halittu) akan Wanene a Red Hill (Devonian Times) 
 Shafin Filin Filin Red Hill Facebook
 Rahoton labarai kan Hynerpeton daga Chicago Tribune (Yuli 29, 1994)
 Rahoton labarai kan Hynerpeton daga NewScientist (Agusta 6, 1994)

Rukuni:Dabbobi
Rukuni:Shafuka masu fassarorin da ba'a duba ba