Kutulukira kwa zinthu zakale zokwiririka pansi sikumangotidabwitsa, ndipo asayansi atulukiranso chinthu china chodabwitsa. Akatswiri ofufuza awonetsa nkhope ya munthu wina yemwe adakhalako zaka zoposa 300 miliyoni zapitazo, ma dinosaurs asanakhalepo. Chokhala ndi utali wa mamita 10, cholengedwa ichi chinali chilombo chapamwamba kwambiri m'malo ake, chimagwiritsa ntchito nsagwada zake zamphamvu kudya nyama zazing'ono ndi tizilombo. Kupezeka kwa cholengedwa chochititsa mantha chimenechi kukuunikiranso mbiri ya moyo wapadziko lapansi, ndipo kukutsegula zitseko za kafukufuku watsopano ndi kumvetsetsa zakale za dziko lapansi.
Mwa kusonkhanitsira pamodzi zidutswa za chigaza cha chigaza chakale, asayansi apanganso nkhope yowopsya ya cholengedwa cha zaka 330 miliyoni chofanana ndi ng’ona, kusonyeza osati kokha mmene chinkawonekera komanso mmene chikanakhalira.
Asayansi adziwa za mitundu yomwe yatha, Crassigyrinus scoticus, kwa zaka khumi. Koma chifukwa chakuti zokwiriridwa pansi zakale zodziwika za nyama zakale zimaphwanyidwa kwambiri, zakhala zovuta kupeza zambiri za izo. Tsopano, kupita patsogolo kwa scanning ya computed tomography (CT) ndi kuwonera kwa 3D kwalola ofufuza kuti adule zidutswazo mwa digito kwa nthawi yoyamba, kuwulula zambiri za chilombo chakale.
Kafukufuku wam'mbuyo wasonyeza zimenezo Crassigyrinus scoticus anali tetrapod, nyama ya miyendo inayi yogwirizana ndi zolengedwa zoyamba kusintha kuchokera kumadzi kupita kumtunda. Ma tetrapods anayamba kuonekera pa Dziko Lapansi pafupifupi zaka 400 miliyoni zapitazo, pamene ma tetrapods oyambirira anayamba kusinthika kuchokera ku nsomba za lobe-finned.
Mosiyana ndi achibale ake, komabe maphunziro apitalo apeza Crassigyrinus scoticus inali nyama ya m’madzi. Zili mwina chifukwa chakuti makolo ake anabwerera kuchokera kumtunda kupita kumadzi, kapena chifukwa chakuti sanafike kumtunda poyamba. M'malo mwake, inkakhala m'madambo a malasha - madambo omwe zaka mamiliyoni ambiri amasanduka masitolo a malasha - komwe tsopano ndi Scotland ndi madera ena a North America.
Kafukufuku watsopano, wochitidwa ndi asayansi ku University College London, akuwonetsa kuti nyamayo inali ndi mano akulu ndi nsagwada zamphamvu. Ngakhale dzina lake limatanthauza "tadpole wandiweyani," kafukufukuyu akuwonetsa Crassigyrinus scoticus anali ndi thupi lathyathyathya ndi miyendo yaifupi kwambiri, yofanana ndi ng’ona kapena ng’ona.
"M'moyo, Crassigyrinus akanakhala pafupi mamita awiri kapena atatu (6.5 mpaka 9.8 mapazi) kutalika, zomwe zinali zazikulu kwambiri panthawiyo," wolemba phunziro lotsogolera Laura Porro, mphunzitsi wa selo ndi chitukuko cha biology ku University College London, mawu. “Mwina zikanachita zinthu mofanana ndi ng’ona zamakono, zobisalira pansi pa madzi ndi kuluma kwake kwamphamvu kuti zigwire nyama.”
Crassigyrinus scoticus adasinthidwanso kuti azisaka nyama m'malo achithaphwi. Kukonzanso kwatsopano kwa nkhope kumasonyeza kuti inali ndi maso akuluakulu kuti awone m'madzi amatope, komanso mizere yozungulira, yomwe imalola nyama kuzindikira kugwedezeka m'madzi.
Ngakhale zambiri zimadziwika Crassigyrinus scoticus, asayansi akudabwitsidwabe ndi mpata womwe uli pafupi ndi mphuno ya nyamayi. Malinga ndi Porro, kusiyana kungasonyeze kuti scoticus inali ndi mphamvu zina zothandizira kusaka. Zitha kukhala ndi chotchedwa rostral organ chomwe chinathandizira cholengedwacho kuzindikira minda yamagetsi, adatero Porro. Kapenanso, scoticus mwina anali ndi chiwalo cha Jacobson, chomwe chimapezeka mu nyama monga njoka ndipo chimathandiza kuzindikira mankhwala osiyanasiyana.
M'maphunziro am'mbuyomu, Porro adati, asayansi adamanganso Crassigyrinus scoticus ndi chigaza chachitali kwambiri, chofanana ndi cha Moray eel. "Komabe, nditayesa kutsanzira mawonekedwewo ndi digito kuchokera ku CT scans, sizinagwire ntchito," adatero Porro. Panalibe mwayi woti nyama yokhala ndi mkamwa waukulu chotere komanso denga lachibade lopapatiza likanakhala ndi mutu wotero.
Kafukufuku watsopano wasonyeza kuti nyamayi ikanakhala ndi chigaza chofanana ndi cha ng’ona yamakono. Kuti akonzenso mmene nyamayo inkaonekera, gululo linagwiritsa ntchito makina ojambulira zinthu zina zinayi zosiyana n’kudulira zinthu zakale zoswekazo kuti zionekere.
"Titangozindikira mafupa onse, zinali ngati chithunzi cha 3D-jigsaw," adatero Porro. "Nthawi zambiri ndimayamba ndi zotsalira za ubongo, chifukwa ndizomwe zimakhala pakatikati pa chigaza, kenako ndikusonkhanitsa mkamwa mozungulira."
Ndi kukonzanso kwatsopano, ochita kafukufuku akuyesa zotsatsira zingapo za biomechanical kuti awone zomwe zingatheke.
Kafukufukuyu adasindikizidwa koyamba mu Zolemba za Vertebrate Paleontology. Meyi 02, 2023.
