Lokacin Silurian

A cikin zamanin Paleozoic mun sami lokacin da ke tattare da tsananin aikin ƙasa kuma wanda yake tsakanin Ordovician da Devonian. Labari ne game da lokaci Siluriyanci. A wannan lokacin wanda akwai babban aiki a ƙasa, zamu iya samun shaidar kimiyya game da samuwar manyan tsaunuka da kuma sabon yankin da ake kira Euramérica.

A cikin wannan labarin zamu gaya muku duk halaye, ilimin ƙasa, yanayi, fure da fauna na zamanin Silurian.

Babban fasali

Lokacin Silurian ya ɗauki kimanin shekaru miliyan 25, farawa daga kimanin shekaru miliyan 444 da suka gabata zuwa shekaru miliyan 419 da suka gabata. A wannan lokacin, al'ada ne a gare ta ta kasance a cikin ruwa mara ƙanƙanci a saman nahiyoyin saboda matakin teku yana da tsawo sosai. Ga masana kimiyya, zamanin Silurian yana da ban sha'awa sosai tunda yana da canje-canje a matakin ilimin kasa da kuma matakin halittu daban-daban.

Shuke-shuke sun sami nasarar mamaye yanayin ƙasa da sabbin nau'ikan halittar ruwa, murjani da kifi sun bayyana. A matakin ilimin kasa, ya kuma yiwu a ga samuwar wasu tsaunuka da muka sani a yau, kamar su Dutsen Appalachian.

Zamanin yanayin kasa na Silurian

A wannan lokacin babban yankin da ake kira Gondwana ya kasance a gefen kudu na duniyar duniyar. Sauran manyan yankuna da aka fi sani da Laurentia, Baltic da Siberia suna cikin matsayi gaba arewa. Matsayin teku ya tashi da yawa sakamakon narkewar kankara daga ƙarshen ƙanƙaniyar lokacin da ya gabata. Wannan tashi a matakin teku Ya haifar da abin da ake kira tekun epicontinental a saman manyan ƙasashe. Waɗannan ƙananan ƙananan ruwa ne waɗanda ba su da zurfin zurfin ruwa waɗanda suka shimfiɗa a duk faɗin waɗannan nahiyoyin.

Sakamakon Gudun daji ya ci gaba da sauya nahiyoyin zuwa kan iyaka. Wannan shine yadda manyan ƙasashe da ake kira Laurentia, Baltica da Avalonia suka zo karo don ƙirƙirar babban yanki mai girma wanda sunan sa shine Euramérica.

Wannan lokacin yana da alamun bayyanar manyan yankuna. Tekunan da ke wannan lokacin sune Panthalassa, Paleo Tethys, Rheico, Lapetus da kuma tekun Ural.

Yanayin lokacin Silurian

Duk tsawon wannan lokacin, yanayin duniya ya daidaita. Babu sauran canje-canje da yawa kwatsam a cikin yanayin a matakin duniya. Mafi mahimmanci ɗan Silurian ya tsaya don kasancewa lokaci tare da yanayi mai ɗumi. Gilashin da suka kafu a lokacin Ordovician suna can gefen kudu na doron duniya kuma sakamakon narkewar da suka yi ya haifar da hauhawar matakin teku.

Kodayake lokaci ne mai ɗumi gabaɗaya gabaɗaya, akwai bayanan burbushin halittu waɗanda ke nuna cewa lokaci ne mai ƙarancin hadari. Bayan haka, yanayin yanayin muhalli na duniya ya fara raguwa, yana sanyaya muhalli kaɗan. Wannan raguwar yanayin bai haifar da shekarun kankara ba. A ƙarshen Silurian kuma tuni ya shiga cikin Devonian sauyin yanayi yana ɗan ɗan yanayi da dumi tare da adadi mai yawa na hazo.

Flora

Duk da cewa a ƙarshen Ordovician akwai babban abin da ya faru na ɓarna, yayin rayuwar Silurian yana ci gaba cikin nasara a cikin halittu masu rai, musamman. Dukkanin jinsunan da suka sami nasarar tsira daga karshen Ordovician sun sami damar yaduwa har ma sun canza zuwa halittu daban-daban.

Bari mu fara nazarin flora. A cikin halittun ruwa akwai yawan algae, galibi kore, wanda ya taimaka wajen samar da daidaito a cikin yanayin. Wannan saboda suna cikin ɓangarorin sarƙoƙi masu tasowa waɗanda ke haɓaka. A wannan lokacin cKwayoyin jijiyoyin jiki sun fara haɓaka waɗanda suke da tasoshin sarrafawa waɗanda suke xylem da phloem.

A farkon wannan lokacin yanayin shimfidar kasa ya sha bamban da na ruwa. A cikin yanayin ruwan teku, rayuwa ta bunkasa kuma ta kara yawaita. Akasin haka, a cikin duk wuraren da ke cikin ƙasa yanayin ya zama mafi ƙaranci da busasshe. Akwai kawai 'yan shimfidawa na duwatsu da wuraren hamada da humus na lokaci-lokaci. Tsirrai waɗanda suka haɓaka a cikin yanayin duniya dole ne su kasance kusa da jikin ruwa. Wannan shine yadda suka sami damar wadatar waɗannan abubuwan da abubuwan gina jiki. Wannan shine yadda tsire-tsire na farko da muka sani yau suke bryophytes suka kasance.

fauna

Game da fauna, a ƙarshen Ordovician akwai aikin hallaka mutane da yawa wanda kuma ya shafi dabbobi sosai. Koyaya, a duk tsawon wannan lokacin, rukunin dabbobi kamar su arthropods sun haɓaka. Daga wannan lokacin sun murmure kusan burbushin 425 dake wakiltar mutanen wannan kwayar halittar. Abubuwan farin ciki sun ragu a cikin lokacin da ya gabata kuma sun ci gaba da kasancewa a cikin halittun cikin ruwa. Koyaya, a yankin, sun mutu.

ma, a lokacin Silurian sun bayyana a karon farko da myriapods da chelicerates. Wadannan rukuni na dabbobi sun fara mamaye wuraren zama. Ofungiyar mollusks ta wakilci a wannan lokacin ta nau'in bivalves da gastropods. Sun rayu galibi a bakin teku.

Crinoids, waɗanda aka gane su a matsayin tsofaffin halittu a duniya kamar yadda suma suka wanzu a wannan lokacin. wadannan suna da wata damuwa wacce ta taimaka musu aka sanya su a kan wuta. Sun mutu a ƙarshen Silurian.

A fagen kifi muna da babban haɓaka. A cikin zamanin da ya gabata ostracodererms ya riga ya bayyana. Waɗannan su ne kifin da ba shi da jayayya kuma ana ɗaukar su mafi tsufa a ƙarshen tarihin burbushin halittu. Sauran nau'ikan kifayen sun fara bayyana, daga cikinsu wadanda suke da jazz wadanda aka fi sani da placoderms suka fita waje. Ofaya daga cikin halayen wakilcin wannan nau'in shine Suna da cuirass a gaban jiki. Wasu kwararru sun tabbatar da cewa a ƙarshen wannan lokacin kifin mai cin nama ya bayyana.

Har ila yau, murjani na Coral yana da mahimmanci tunda sun bayyana a wannan lokacin. Anan ne da gaske aka samar da manyan duwatsun murjani. Wannan saboda nau'ikan murjani na yanzu ana iya rarrabe shi ta hanyar gwaji godiya ga jujjuyawar yanayi.

Ina fatan cewa tare da wannan bayanin zaku iya ƙarin koyo game da zamanin Silurian.