Dabbobin masu shayarwa: Nau'i, Halaye da Misalai

Dabbobi masu shayarwa su ne rukunin dabbobin kashin baya waɗanda aka bambanta saboda matansu suna da glandar mammary don ciyar da 'ya'yansu. Dabbobin dabbobi masu shayarwa sun kasance mafi yawan dabbobi da ake rarrabawa a duniya baki daya, kuma an fi yin nazari ne saboda kasancewar mutane na cikin wannan rukunin.

dabbobi masu shayarwa

Dabbobi masu shayarwa (Mammalia) suna cikin rukuni na kashin baya masu jini da ɗumi, waɗanda abin da ke bambanta su shine mallakar glandan shayarwa da suke samar da madara don ciyar da 'ya'yansu. Yawancin su viviparous ne (sai dai monotremes: platypus da echidnas).

An rarraba su a matsayin rarrabuwa na kimiyya ko rukuni na nau'ikan da suka samo asali daga kakanni guda ɗaya (monophyletic taxon or clade), wato, dukkansu sun fito ne daga kakanni ɗaya mai yiwuwa tun daga ƙarshen zamanin Triassic, fiye da shekaru miliyan 200 da suka wuce.

Suna cikin ɓangaren synapsid clade, wanda kuma ya ƙunshi "masu rarrafe" da yawa masu alaƙa da dabbobi masu shayarwa, irin su pelycosaurs da cynodonts. A gabatar da wasu nau'ikan 5.486, kasancewa 5 daga cikinsu na monotemata, 272 Marsupials da sauran, 5.209 masu ɗora wuri. A matsayin ilimin ilimin kimiyya, ilimin nama ko ilimin dabbobi, an san ilimin kimiyya da aka sadaukar don nazarin dabbobi masu shayarwa.

Halayen Dabbobin Mammali

Rukunin halittu masu shayarwa suna da bambanci sosai duk da matsakaicin adadin nau'ikan da ke tattare da su idan aka kwatanta da sauran harajin dabbobi ko shuka. Nazarin kimiyya na dabbobi masu shayarwa ya kasance mafi zurfi a fagen ilimin dabbobi, babu shakka saboda kasancewar jinsin ɗan adam nasa ne. Irin wannan nau'in nau'in nau'in dabbobi masu shayarwa ne wanda ga wanda ba shi da kwarewa zai yi wuya a iya tantance ko wane nau'in nau'in dabba ne kuma wanda ba haka ba ne.

Don fayyace wannan dabi'a, anatomical-physiological da ethological iri-iri tare da misali, ya isa a haɗa wasu nau'ikansa, kamar ɗan adam (Homo sapiens), kangaroo rufus (Macropus rufus), chinchilla (Chinchilla lanigera). farin whale ( Delphinapterus leucas ), giraffe ( Giraffa camelopardalis ), lemur mai zobe (Lemur catta), jaguar (Panthera onca) ko jemagu ("Chiroptera").

Ajin dabbobi masu shayarwa rukuni ne na monophyletic, tunda duk membobinsa suna raba jerin bambance-bambancen juyin halitta na musamman (synapomorphies) waɗanda ba a samun su a cikin kowane nau'in dabbar da ba sa cikin wannan ajin:

• Yana da glandon gumi, wanda ya canza kamar glandar mammary, tare da ikon fitar da madara, wani sinadari wanda aka samar da dukkan zuriya masu shayarwa da shi. Wannan shi ne ainihin asalin sa, wanda sunan sa na dabbobi masu shayarwa ya fito.
• Muƙamuƙi ya ƙunshi kashi na hakori ne kawai, na musamman kuma keɓantacce na wannan ajin duka, yana samar da babban sifa wanda ke taimakawa don gane ƙungiyar.
• Yana da kashin baya bakwai a cikin sashin mahaifa na kashin baya; Halin ilimin halitta wanda ke samuwa a cikin nau'ikan nau'ikan da ba su da bambanci kamar linzamin kwamfuta, raƙuman ruwa, platypus ko blue whale.
• Haɗin gwiwa na mandible tare da kwanyar yana faruwa tsakanin haƙoran haƙora da squamosal, daidai da na musamman da keɓancewar wannan ajin.
• Suna da ƙasusuwa guda uku a cikin kunni na tsakiya: guduma, anvil da stirrup, sai dai monotremes, wanda kunnensa mai rarrafe ne.
• Dabbobi masu shayarwa suna da kunun kunne, ban da whales, dolphins da sauran waɗanda ke rayuwa a cikin ruwa kuma, a cikin juyin halittarsu, ƙila sun rasa su saboda dalilai na ruwa.
• Wannan nau'in shine kawai nau'in nau'in dabba da ke da Jawo a duk tsawon rayuwar sa, kuma kowane nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i) wanda ke da Jawo a cikin kowane nau'i na kasancewarsa,kuma kowane nau'in nau'in nau'in nau'in nau'in nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nau'i-nauyi ne (duk da haka a cikin yanayin amfrayo).
• Kamar kakanninsu na farko, dabbobi masu shayarwa na yanzu suna da ramuka guda biyu na wucin gadi a cikin kwanyar, sabanin diapsids (dinosaurs, dabbobi masu rarrafe na yanzu da tsuntsaye), waɗanda ke da nau'i biyu, da anapsids (kunkuru), waɗanda ba su da. babu komai.
• Bugu da ƙari ga wannan kwarangwal kwarangwal, da sauran ƙananan mahimmanci (kamar mahimmancin kashi na hakori a cikin ƙananan muƙamuƙi da kuma iyawar hakora don yin ayyuka daban-daban ko yanayin heterodont), abubuwan farko na dabbobi masu shayarwa shine kasancewar Jawo. da kuma fata gland.

Amma duk da wadannan da sauran kamanceceniya da ba su ayyana ajin, nau’insa ya kai yadda bambance-bambancen da ke akwai ya fi yawa, musamman dangane da bayyanar waje.

Asalin da juyin halitta

Dabbobin shayarwa na yau sun fito ne daga asali na synapsids, rukuni na tetrapods na amniotic wanda ya fara bayyana a farkon Permian, kimanin shekaru miliyan 280 da suka wuce, kuma sun ci gaba da kasancewa a kan "masu rarrafe" na duniya har zuwa kimanin shekaru miliyan 245 (farkon Triassic) baya, lokacin da dinosaur na farko suka fara ficewa. Ƙaddamar da fifikonsu na gasa, na ƙarshe ya haifar da bacewar yawancin synapsids.

Duk da haka, wasu sun tsira, kuma magajin su, mammaliaforms, daga baya sun zama ainihin dabbobi masu shayarwa na farko zuwa ƙarshen Triassic, kimanin shekaru miliyan 220 da suka wuce. Tsofaffin dabbobi masu shayarwa su ne, a gefe guda, masu yawa da kuma, a daya bangaren, australosphenids, kungiyoyin da suka koma Jurassic ta Tsakiya.

Koyaya, dole ne a la'akari da cewa ƙungiyar Mammalian, bayan nasarar farko a cikin Permian da Triassic, an kusan maye gurbinsu gaba ɗaya, a cikin Jurassic da Cretaceous (kimanin shekaru miliyan 100), da dabbobi masu rarrafe (dinosaurs, pterosaurs, crocodilians). , plesiosaurs, ichthyosaurs, mosasaurs, da pliosaurs), kuma sai da hadarin meteorite ya haifar da bacewar taro na Cretaceous-Tertiary ne dabbobi masu shayarwa suka zama daban-daban kuma sun sami babban matsayi.

Yin amfani da albarkatu ba tare da yin gogayya da manyan dabbobi ba yana nufin daidaitawa zuwa wuraren da ba su da kyau tare da yanayin sanyi akai-akai, zuwa abubuwan yau da kullun na dare, tare da ƙarancin zafi kuma waɗanda aka ƙara ɗan haske.

A cikin tarihin juyin halitta na dabbobi masu shayarwa, jerin abubuwan da suka faru suna faruwa waɗanda zasu bayyana samun halayen da ke nuna ajin. Siffar homeothermic, wato, daidaita yanayin zafin jikin su, babu shakka ingancin da ke ba da dama ga dabbobi masu shayarwa a duniya ba tare da gasa ba da yalwar albarkatun abinci mai gina jiki. Godiya ta tabbata a gare ta cewa sun sami damar mamaye yankuna masu sanyi kuma, musamman, yin ayyukan dare.

Ci gaban capillary wanda ke ba da kariya ga jiki daga asarar zafi da kuma haɓaka hangen nesa da ke dacewa da ƙananan haske shine sauran abubuwan biyu da suka taimaka wajen zama na waɗannan abubuwan muhalli har sai lokacin ba tare da kasancewar dabbobi mafi girma ba. Daidaitawar kwarangwal shine matakin farko don cimma babban tasirin makamashi dangane da karuwar amfani da albarkatu da rage kashe kudade.

Kwanyar kwanyar tana zama mafi tasiri, tun lokacin da aka rage yawan adadinsa yayin da yake kiyaye juriya da kuma sanya tsarinsa ya fi sauƙi yayin da yake ba da damar haɓakawa da tasiri na tsokoki da aka kara don karuwa a cikin kwakwalwa (kwakwalwa) da kuma mafi girman iyawar hankali.

Canje-canjen kwanyar kuma yana haifar da samuwar ƙoƙon baki na biyu, tsarin mulkin sarkar kasusuwa na kunne na tsakiya da ƙwararrun sassan hakori. An kafa muƙamuƙi daga kashi ɗaya (haƙori) kuma wannan shine babban abin da za a iya kammalawa idan burbushin dabba yana cikin nau'in dabbobi masu shayarwa, saboda yawan asarar kyallen takarda ta hanyar burbushin halittu.

Gaɓar gaɓoɓin suna tsayawa a hankali suna magana a gefen gangar jikin don yin haka a ƙasa. Ta wannan hanyar, yayin haɓaka motsi na dabba, yana rage yawan kashe kuzari ta hanyar rage abubuwan da ake buƙata don locomotion da riƙe jiki a tsaye.

A nasu bangaren, ciki na ciki na ‘ya’ya da kuma ikon ciyar da su a farkon shekarunsu na farko ba tare da nemansa (madara) ba, ya sanya iyaye mata su sami ‘yancin yin motsi da kuma ci gaba a cikinsa. Iyawar rayuwarsu, musamman na nau'in.

Ta duk waɗannan gyare-gyare na juyin halitta, kowane ɗayan abubuwan da aka tsara na kwayoyin halitta, da kuma tsarin ilimin lissafin jiki, sun shiga ciki. Na'urar nazarin halittu, lokacin da ta ƙware, ta buƙaci ingantacciyar tasiri a cikin numfashi da narkewar abinci, haɓaka haɓakar tsarin jijiyoyin jini da na numfashi dangane da tasirin ilimin halittar jiki, da na tsarin narkewa don cimma babban fa'idar abinci mai gina jiki. Waɗannan su ne sauran nasarorin da waɗannan dabbobi suka samu a tsawon juyin halittarsu.

Na'urar jin tsoro ta tsakiya sannu a hankali ta sami girma da ƙungiyar histological da ba a san su ba a cikin sauran dabbobi, kuma rashin hasken da nau'ikan dare ke fuskanta ya sami ramawa ta hanyar haɓakar sauran gabobin, musamman ji da wari. Duk waɗannan abubuwan da suka faru na juyin halitta an samu su a cikin shekaru miliyan ɗari da yawa, bayan haka mu dabbobi masu shayarwa sun sami nasarar sarrafa rayuwa a duniya.

Ka'idar Juyin Halitta na Mambobi

Littafin da dabbobi masu rarrafe suka samo asali daga dabbobi masu rarrafe, a fili an yarda da su baki ɗaya, yana mai nuni da cewa ci gaban su shine don cin gajiyar abubuwan da suka shafi muhalli wanda a baya ba zai yiwu a daidaita su ba. Juyin halittarsu daga synapsids ("masu dabbobi masu rarrafe") sun faru a hankali sama da shekaru miliyan 100 tsakanin Tsakiyar Tsakiya da Jurassic ta Tsakiya, tare da fashewar nau'ikan nau'ikan da ke faruwa a tsakiyar Triassic.

Ingancin sa na homeothermic shine farkon wannan tsari a hankali. Lokacin da kakannin kakannin dabbobi masu shayarwa suka yi nasarar daidaita yanayin jikinsu, sun sami damar mamaye wuraren da yanayin zafi ya kasa kasa samun nau'in ectothermic (jinin sanyi) su rayu, don haka suna gudanar da al'adar dare da cin gajiyar albarkatun abinci. cewa kafin su kasance sun fi karfin magabata.

Don wannan dalili dole ne su canza tsarin su da ayyukansu, a gefe guda don kiyayewa da musayar zafi tare da muhalli, a daya bangaren kuma don dacewa da yanayin dare. Ƙirƙirar wani nau'i mai rikitarwa wanda zai kare su, na tsarin locomotor mai iya ceton makamashi yayin motsi da rage yanki na jiki, da kuma gabobin jiki don inganta mahimmancin mahimmanci shine mataki na farko don fara sarrafa sababbin halittu.

Ta hanyar haɓaka motsi, ya zama dole don adana makamashi, wanda ya haifar da tsarin tsarin narkewa mai rikitarwa da inganci, wanda, yayin da yake rage lokacin narkewa, ya kara matakin da ake amfani da abinci. Don haka, tsarin jini ya zama mafi ƙarfi da ƙwarewa, yana kawo haɓakar tsarin numfashi, wanda ya ƙara yawan ƙarfinsa da isasshen iskar oxygen.

A cikin wannan jerin sauye-sauye, duk na'urori da tsarin halitta sun samo asali kuma sun ƙware a cikin dogon lokaci fiye da shekaru miliyan ɗari da sittin. Sakamakon gagarumin gushewar dinosaurs (banda zuriyarsu, tsuntsaye) a karshen Cretaceous, kimanin shekaru miliyan 65 da suka wuce, kuma bayan wani lokaci na wucin gadi wanda manyan tsuntsaye (Gastornis) suka fi rinjaye, dabbobi masu shayarwa sun ƙare. Ya yi nasara a cikin Cenozoic.

Halin zamantakewa

Hakazalika, babban buƙatun makamashi na waɗannan dabbobi yana daidaita halayensu, wanda, ko da yake yana canzawa sosai daga wannan nau'in zuwa wani, yawanci yana da manufar ceton kuzari don kula da zafin jiki.

Yayin da dabbobi masu shayarwa da ke mamaye yankuna masu sanyi na duniya dole ne su hana hasarar zafin jiki, waɗanda ke rayuwa a cikin yanayi mai zafi da bushewa suna jagorantar ƙoƙarinsu na gujewa yin zafi da bushewa. Halin dukansu, saboda haka, an ƙaddamar da shi don kiyaye ma'auni na ilimin lissafi, duk da yanayin muhalli.

Dabbobi masu shayarwa yawanci suna cikin kowane nau'in rayuwa: akwai nau'ikan arboreal da sauran halaye na ƙasa, akwai kawai dabbobi masu shayarwa na ruwa da sauran amphibians, har ma da waɗanda ke ciyar da rayuwarsu ta ƙarƙashin ƙasa suna tono galleries a cikin yashi. Salon motsi kuma sun bambanta, don haka: wasu suna iyo, wasu kuma suna tashi, gudu, tsalle, hawa, rarrafe ko shiri.

Hakazalika, halin zamantakewa ya bambanta sosai tsakanin nau'in: akwai waɗanda suke rayuwa su kaɗai, wasu suna rayuwa bi-biyu, a cikin ƙananan ƙungiyoyin iyali, a cikin ƙananan yankuna har ma a cikin manyan garken dubban mutane. A gefe guda kuma, suna bayyana ayyukansu a lokuta daban-daban na yini: rana, dare, faɗuwar rana, maraice har ma da irin su yapok (Chironectes minimus) waɗanda a fili ba sa nuna zaƙi na circadian.

Ilimin Halittu da Ilimin Halitta na Dabbobin Mammali

An riga an jaddada abubuwan da suka shafi synapomorphic na ajin dabbobi masu shayarwa. Duk nau'ikan sa suna gabatar da su kuma sun keɓanta ga ajin:

• Haƙori a matsayin keɓantaccen kashi na muƙamuƙi, wanda aka haɗa tare da squamosal a cikin kwanyar.
• Sarkar kashi na tsakiyar kunne: malleus (malleus), incus (incus) da stapes (stapes).
• Jawo a yankin jikinsa.
• Mammary glands masu samar da madara.
• Bakwai na kashin baya a cikin sashin mahaifa na kashin baya.

Hakora na kunshe da sinadarai wadanda ba sa cikin tsarin kashi, sai dai suturta kwayoyin halitta ko gabobin jiki, kamar fata, farce da gashi. Abubuwan da ake yin yawan haƙora daga cikin haƙorin hauren giwa ne ko kuma dentin, wanda gabaɗaya an rufe shi a waje da wani sashi mai wuyar gaske, enamel, yayin da a gindin haƙori abin rufewa ya kasance da abu na uku da ake kira. siminti.

A cikin dabbobi masu shayarwa, hakora a ko da yaushe suna cikin kasusuwa na kwanyar da ke kunshe da baki, wadanda ke sama, maxillae guda biyu da na premaxillae, kuma a ƙasa, mandible ko jaw, wanda ke manne da muƙamuƙi kai tsaye. kwakwalwar kwakwalwa.

Na karshen, a nasa bangare, yana haɗi tare da kashin baya ta hanyar wasu manyan mashahuran, ko kuma nau'in condyles a kowane gefen kogin wanda kashin baya ya shiga don shiga cikin kwakwalwa.

Kodayake yawan adadin vertebrae a cikin kashin baya yana hawa da gaske kamar yadda ake shukar halitta guda bakwai ko kuma wuyan dabbobi waɗanda ke da shida da kuma Manate.. Koyaya, ƙari ga wannan, akwai wasu halaye masu alaƙa da waɗannan nau'ikan ta yadda za mu iya gane su a matsayin ɓangare na taxon:

• Ana gane dabbobi masu shayarwa a matsayin nau'in dabbobin da ke da kashi ɗaya a kowane muƙamuƙi, haƙori, kai tsaye a manne da kwanyar. Kasusuwan muƙamuƙi na dabbobi masu rarrafe sun zama biyu daga cikin ƙasusuwan uku waɗanda suka haɗa da sarkar kasusuwa na kunne, guduma (haɗin gwiwa) da majiya (square). Matakan sun fito ne daga ƙashi kaɗai da dabbobi masu rarrafe ke nunawa a cikin kunne, columella.
• Hakora sun zama ƙwararru sosai ta hanyar halayen cin abinci, kuma galibi ana maye gurbinsu sau ɗaya a rayuwa (diphyodontia).
• Akwai ƙoƙon baki na biyu wanda ke da ikon rarraba hanyar iska zuwa mashigar ruwa daga hanyar ruwa da abinci zuwa gabobin narkewar abinci.
• Diaphragm shine tsarin tsoka wanda ke raba ɗakin thoracic daga ɗakin ciki kuma yana taimakawa wajen aikin narkewa da numfashi. Ana samunsa ne kawai a cikin dabbobi masu shayarwa kuma kowane nau'in suna da shi.
• Zuciya ta kasu kashi hudu kuma a cikin manya kawai ana haɓaka baka na aortic na hagu.
• Kwayoyin jini jajayen kwayoyin halitta ne a yawancin nau'ikan dabbobi masu shayarwa.
• Lobes na cerebral sun bambanta sosai kuma ƙwayar ƙwayar ƙwayar cuta ta samo asali sosai, tare da bayyanannun ƙayyadaddun abubuwa a cikin nau'ikan da ke da ƙwarewar hankali.
• Tun daga lokacin tsarin mulkin zygote ta chromosomes na jima'i, an ƙayyade jima'i: biyu daban-daban a cikin maza (XY), biyu iri ɗaya a cikin mata (XX).
• Hadi na ciki a cikin kowane nau'i.
• Duk nau'ikan su ne endothermic, wanda ke nufin cewa za su iya haifar da zafi tare da jikinsu, kuma, ƙari, yawancin su ne homeothermic, wanda ke nufin cewa za su iya kula da zafinsu a cikin takamaiman kewayon. monotremes kawai suna nuna wasu iyakoki na wannan ikon.

Dabbobin Fatar Dabbobi

Fatar, yawanci mai yawa, tana yin ta ne daga bangon waje ko epidermis, Layer na ciki ko dermis, da wani nau'in fata mai cike da kitse wanda amfaninsa shine kariya daga asarar zafi, tunda dabbobi masu shayarwa nau'in gida ne. Biyu daga cikin synapomorphies na nau'in dabbobi masu shayarwa ana samun su a cikin fata: Jawo da glandan mammary.

Fata yana da hannu kai tsaye a cikin kare dabba, ikon thermoregulatory, kwashe kayan sharar gida, sadarwar dabba da samar da madara (mammary gland). Sauran jikin jikin fata na ƙaho da ke cikin dabbobi masu shayarwa sune ƙusoshi, faratai, kofato, kofato, ƙahoni da baki na platypuses.

Locomotor na'ura

Tsarin locomotor shine hanyar sadarwa mai rikitarwa na kyallen takarda na nau'in dabi'a daban-daban wanda ke ba da izinin kiyaye jikin dabba da motsinta.

Axial Skeleton:

• Kai: kokon kai da jaw.
• Rufin Vertebral: mahaifa, thoracic, lumbar, sacral da caudal ko coccygeal vertebrae.
• Thoracic Chamber: sternum da haƙarƙari.

Ƙwaƙwalwar kwarangwal:

• Gindin kafada: clavicle da kafada ko scapulae.
• Tsoffin Membobi: humerus, ulna, radius, carpus, metacarpus da phalanges.
• Ƙarƙashin ƙashin ƙugu: ilium, ischium da pubis.
• Ƙarshen baya: femur, patella, tibia, fibula, tarsus, metatarsus da phalanges.

Baya ga haka, akwai sauran jikin kasusuwa kamar kasusuwan na'urar hyoid (tallafin harshe), kunnen tsakiya, kashin azzakari na wasu masu cin nama da ma kasusuwan zuciya na wasu bovids wadanda sabbin kayan kasusuwa don an halicci guringuntsi. Baya ga tsarin kasusuwa, tsarin musculoskeletal ya ƙunshi tsarin tsoka da tsarin haɗin gwiwa.

Tsarin narkewar abinci

Tsarin narkar da abinci yana kunshe ne da hanyar shiga, ko kuma hanji, wani bututun hanji ta karshensa ake zubar da sharar zuwa waje da ciki, da wasu nau’in glandon da aka makala, inda mafi muhimmanci su ne hanta da pancreas.

Ban da wasu lokuta, kafin abinci ya shiga cikin tsarin, a baya ana shirya shi ta hanyar taunawa, wanda hakora ke aiwatar da su, wadanda ke da wuyar gabobin da ke kare baki kuma adadinsu da siffarsa suna canzawa sosai bisa ga ciyarwar. abinci.Kowane jinsi.

A mafi yawan lokuta akwai, da farko, wasu yankan hakora, da ake kira incisors, sai kuma ƙwanƙwasa, ko canines, waɗanda suka dace da tsagewa, da kuma, a ƙarshe, wasu masu amfani don murƙushewa da niƙa, waɗanda ake kira su hakora ko ƙwanƙwasa. .

Gabaɗaya, dabbobi masu shayarwa suna da haƙoran haƙora a lokacin ƙuruciyarsu kuma daga baya ana maye gurbinsu da wasu. Tsarin narkewar dabbobi masu shayarwa shine tsarin visceral tubular wanda abinci ke ƙarƙashin kulawa mai zurfi don samun babban fa'ida daga abubuwan gina jiki.

Ta hanyar wucewar narkewar abinci daga lokacin da aka ci shi har sai an fitar da shi, abincin yana fuskantar ƙaƙƙarfan tsari na ɓarnawar inji da sinadarai wanda jerin gabobin jiki da kyallen takarda ke shiga cikin dabara.

Jadawalin Tafiyar Narkar da Abinci:

• Baki: tauna da salivation tare da assimilation na 'yan sassa.
• Esophagus: wucewa tare da ɗanɗano kaɗan.
• Ciki: tsari na inji da sinadarai na narkewa tare da juzu'i na abubuwan gina jiki.
• Ƙananan hanji: narkewar inji da sinadarai (enzymatic da na kwayan cuta) tare da ɗimbin narkewar abinci.
• Babban hanji: inji da sunadarai (kwayoyin cuta) narkewa tare da assimilation na ruwa da kuma ma'adinai salts, da farko.
• Shekara: Korar.

Ilimin ilimin halittar jiki da tsarin jikin wannan gabobin an fi saninsa ne ta hanyar abincin dabba.

Na'urar Numfashi da Wuta

Wadannan tsarin guda biyu suna da alhakin musayar iskar gas da rarraba su a cikin jiki. Dabbobi masu shayarwa suna shakar iskar oxygen daga iska, wanda ake tsotse shi ta hanyar iskar numfashi (baki, hanci, makogwaro, da trachea) kuma ana rarraba ta ta hanyar buroshi da mashako zuwa ga dukkan tsarin saccular, wanda ya kunshi alveoli na huhu.

Jini daga kyallen takarda yana ɗaukar carbon dioxide kuma idan ya isa ga alveolar capillaries, ya watsar da shi yayin shan iskar oxygen. Za a sake gudanar da wannan zuwa zuciya kuma daga can zuwa dukkan kyallen takarda don samar musu da iskar gas da ake buƙata don numfashi ta salula, dawowa don canja wurin sauran carbon dioxide zuwa huhu.

Zane da aiki na duk waɗannan gabobin da kyallen takarda an haɗa su gaba ɗaya don yin aiki mai riba, musamman a cikin ruwa ko na ƙasa inda aka hana iskar oxygen.

Tsarin Jijiya da Gaɓoɓin Ji

Na'ura mai juyayi wani hadadden tsari ne na sel na musamman na musamman, kyallen takarda da gabobin da aikinsu shine gane abubuwan kuzari iri daban-daban, canza su zuwa sinadarai masu amfani da wutar lantarki don fitar da su zuwa kwakwalwa, gano su anan kuma a aika da martani wanda za a sake sanar da su. a matsayin siginar siginar lantarki - sinadarai zuwa gabobin jiki ko nama da aka lalata yayin aiwatar da shi.

An tsara tsarin jijiya ta asali kamar haka:

Tsarin Jijiya ta Tsakiya:

• Encephalon: cerebellum, cerebellum, da kwakwalwar kwakwalwa.
• Kashin baya.

Tsarin juyayi na gefe:

• Jijiya.
• neural ganglia.

Kowace gabar jiki, a gefensa, jiki ne mai yalwar jijiyoyi masu yawa wanda ke da ikon ƙaddamar da abubuwan motsa jiki na waje zuwa bayanai don danganta mutum da yanayin su. Gabaɗaya, wari, ji, gani da taɓawa sune mafi mahimmanci a cikin dabbobi masu shayarwa, kodayake a cikin wasu ƙungiyoyi, wasu abubuwan jin daɗi kamar faɗakarwa, magnetosensitivity ko ɗanɗano sun fi dacewa.

Sake bugun

A cikin mafi yawan dabbobi masu shayarwa, rabuwa da jima'i yana samuwa kuma haifuwa yana da dabi'ar viviparous, ban da ƙungiyar monotremes, wanda shine oviparous. Juyin halittar tayi yana tare da samuwar jeri na kayan amfrayo, kamar su chorion, amnion, allantois da jakar gwaiduwa.

Gashin chorion, tare da allantois, suna manne da bangon mahaifa wanda ke haifar da mahaifa, wanda ke manne da tayin ta cikin igiyar cibi, kuma ta hanyarsa ne abubuwan da ke cikin jiki ke kewaya mahaifa zuwa tayin.

Lokacin gestation da adadin matasa akan kowane zuriyar dabbobi suna canzawa sosai bisa ga ƙungiyoyi. A kai a kai, girman girman dabbar, mafi tsayi lokacin gestation da ƙananan adadin zuriya. Yawancin dabbobi masu shayarwa suna ba 'ya'yansu kulawar iyaye.

A ƙarshe, hanyarsa ta haifuwa daidai ce ta dabbobi masu shayarwa. Ko da yake wasu nau'in nau'in oviparous ne, wato kwai da aka haifa suna fitowa waje suna samar da kwai, a mafi yawancin, amfrayo yana tasowa a cikin jikin uwa kuma ana haife shi a cikin yanayin ci gaba. Daga nan ne aka fara rarrabuwa na rukuni a cikin dabbobi masu shayarwa waɗanda aovan (kwai-kwai) da dabbobi masu shayarwa viviparous.

Rukuni na biyu ana kiransa therians, kalmar da ta samo asali daga Girkanci na gargajiya ma'ana "dabbobi", da kuma wadanda suke oviparous, prototherians, wanda ke nufin "dabbobin farko", tun da akwai burbushin halittu ya sa ya yiwu a yi zaton cewa tsofaffin dabbobi masu shayarwa da suka fito a cikin su. duniya sun kasance cikin wannan rukuni.

Hatta a cikin masana ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmin ilmi, ya zama dole a bambance masu shayarwa da aka haifa a cikin wani mawuyacin hali na rashin ci gaba, wanda za su shafe wani lokaci a cikin jakar da mace ke da shi a cikin fata na ciki, da sauran wanda a ciki. Irin wannan keɓantacce yana faruwa.

Wadanda aka fara nunawa su ne metatherians (wanda ake kira marsupials), wanda ke nufin, "dabbobin da ke zuwa a baya", wadanda ke ci gaba da prototherians, da kuma wadanda suka bayyana a karshe su ne masu shayarwa ko masu shayarwa na placental. A cikin ajin da muka sadaukar da kanmu, waɗannan sune mafiya yawa.

Dabbobi Diversity Mammals

Kawai daidaita nau'in dabba mafi mahimmanci waɗanda suka taɓa rayuwa, tare da 160-ton blue whale (Balaenoptera musculus) da Kitti's hog-nosed bat (Craseonycteris thonglongyai), wanda ake ɗaukarsa a matsayin ƙaramin dabbar dabbar da manya ke auna nauyin gram 2 kawai, zamu iya ganin cewa Bambanci tsakanin nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i)) da kuma mafi girma fiye da sau miliyan 80.

Babban daidaitawar daidaikun mutanen da ke cikin wannan ajin ya kai su ga mamaye dukkan halittun duniya, wanda ya haifar da bambance-bambancen dabi'u, physiological da halayya, wanda ya mayar da su gaba daya zuwa daya daga cikin manyan kungiyoyi a duniya. .

Sun sami damar cin galaba akan koren rigar daji da ƙasan hamada, ƙanƙarar ƙanƙara mai ƙanƙara da ruwan zafi mai zafi, yanayin da ba za a iya numfashi ba na tuddai masu tsayi da ƴaƴa da faffadan savannai da ciyayi.

Wasu na iya yin rarrafe, wasu suna tsalle yayin da wasu za su iya gudu, iyo ko kuma su tashi. Yawancin su suna iya cin gajiyar nau'ikan kayan abinci iri-iri, yayin da wasu suka kware a takamaiman abinci. Waɗannan ƙarancin yanayi sun tilasta wa waɗannan dabbobi su haɓaka, suna samun nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan, daidaitawa, iyawa da wasan kwaikwayo.

Yana da sha'awar tabbatar da yadda, a lokuta da yawa, nau'in da ke da nisa da juna, na yanki da phylogenetically, sun bi irin wannan tsarin tsarin halittar jiki, ayyuka na ilimin lissafi da halayen halayen. Wannan yanayin da aka sani da juyin halitta convergent. Kwatankwacin da ke tsakanin kan kerkeci mai launin toka (Canis lupus, placental) da thylacine (Thylacinus cynocephalus, marsupial) yana da ban mamaki, tare da nau'ikan nau'ikan biyu sun kasance nesa ba kusa da phylogenetically.

Babban bushiya na Turai (Erinaceus europaeus, placental) da echidna na kowa (Tachyglossus aculeatus, monotreme) na iya ɓata wa ƙwararrun ƙwararrun ƙwararru, saboda ba wai kawai sun sami tsarin tsaro iri ɗaya ba, amma suna da nau'ikan sifofi iri ɗaya don cin gajiyar abinci iri ɗaya. albarkatun.

Daidaita Zuwa Muhalli Mabambanta

Yawancin nau'ikan dabbobi masu shayarwa suna haifarwa daga iyawa ta musamman don daidaitawa wanda ya ba su damar yaduwa a yawancin yankunan duniya. Ayyukan da kowane iri-iri suka haɓaka don samun dacewa da muhalli sun ci gaba da kansu.

A cikin wannan hanyar, yayin da wasu nau'ikan kamar su polar bear (urdus maritimus) ya bayyana da fari lokacin da aka yiwa rigar da aka yiwa kolin da ke nuna lokacin farin ciki Layer na nama mai kitse a ƙarƙashin fata.

A wasu lokatai, nau'ikan da ke da nisa sosai ta hanyar phylogenetic suna amfani da irin wannan hanyoyin don dacewa da yanayi iri ɗaya. Juyin halittar kunne pinnae na fennec fox (Vulpes zerda) da giwar Afirka (Loxodonta africana) don haɓaka yankin musayar zafi da fa'idar homeostasis misali ne na fili.

Komawar ruwa ta dabbobin da suke na ƙasa kawai wata alama ce ta iya karɓuwa na dabbobi masu shayarwa. Ƙungiyoyi daban-daban na ajin sun haɓaka gaba ɗaya cikin ikon kansu don komawa cikin yanayin ruwa da kuma cin gajiyar abubuwan da ke cikin teku da kogin.

Don ambaci wasu misalan da ke nuna bambancin hanyoyin da suka ɓullo da su don dacewa da rayuwa a cikin ruwa, umarni biyu waɗanda nau'ikan su ne ainihin ruwa, Cetacea da Sirenia, iyalan carnivores Odobenidae (walrus), Pocidae (hatimi) da Otariidae ( bears da zakoki na teku), mustelids irin su otter na teku (Enhydra lutris) da sauran nau'ikan kogin, rodents irin su beaver (Castor sp.) ko capybara (Hydrochoerus hydrochaeris), Pyrenean desman (Galemys pyrenaicus), hippopotamus ( Hippopotamus amphibius), yapok (Chironectes minimus), platypus (Ornithorhynchus anatinus)…

Kamar dai tsuntsaye da batattu pterosaurs, rukunin dabbobi masu shayarwa, jemagu sun sami ikon yin tafiya ta jirgin sama mai aiki. Ba wai kawai sun sami damar haɓaka mahimman saiti na jikin mutum kamar fuka-fuki ba, har ma sun haɓaka gyare-gyaren physiological waɗanda ke ba da damar tanadin makamashi, don haka magance babban kuɗaɗen da ke tattare da tashi.

Waɗannan dabbobin, kuma, suna yin aiki a cikin mafi tsananin duhu na dare da cikin kogo, sun haɓaka ta hanyar inganta tsarin ƙararrawa wanda ke ba su damar fahimtar duniyar da ke kewaye da su daidai. Moles da sauran nau'ikan burrowing, da farko rodents, lagomorphs, da wasu marsupials suna zaune a ƙarƙashin ƙasa, wasu sun rage na tsawon rayuwarsu.

Sun yi nasarar mamaye sararin samaniyar karkashin kasa, amma fahimtar duniyar waje, motsi na karkashin kasa, alakar da ke tsakanin daidaikun mutane da bukatun abinci mai gina jiki da na numfashi wasu daga cikin batutuwan da ya kamata su warware a tsawon juyin halittarsu, suna yin gwaji ta hanyar. yana da mahimmancin sauye-sauye da ƙwararrun da ba makawa.

Kuma wannan ƙwarewa ta bi da bi tana mayar da waɗannan dabbobin zuwa waɗanda ke da iko mafi girma da kuma rashin lahani. A cikin ci gaba na juyin halitta, akwai jinsin daban-daban, iyalai kuma ma duk umarnin da suka shuɗe yayin da suka canza.

Saboda haka, a yau, wata kila wani dabba mai shayarwa, Homo sapiens, ya zama sanadin bacewar wasu nau'ikan adadi kai tsaye ko kai tsaye. Ta irin wannan hanyar da raguwar wuraren farautar budurwa ke haifar da bacewar lynx na Iberian (Lynx pardina), feline da ta fi fuskantar barazana a duniya, saran gandun daji na kusa da zai haifar da rugujewar giant panda (Ailuropoda melanoleuca) ko haɗa nau'ikan ƙasashen waje irin su kuliyoyi, karnuka ko foxes, tare da kuliyoyi maras kyau na Ostiraliya.

Takardar Muhalli

Yana da wuya a yi ƙoƙarin taƙaita irin rawar da nau'ikan dabbobi masu shayarwa kusan 5.000 ke takawa kamar yadda ake ƙoƙarin yin hakan dangane da dukkan abubuwa masu rai da muhallinsu. Iri-iri na halittun da aka mamaye, dabi'un halitta da zamantakewa gami da tsarin halittar jiki da daidaita yanayin halittar dukkansu, yana haifar da rashin kulawa ga duk wata dabba ko gungun tsiro a doron kasa, duk da kasancewarta mafi ƙarancin rukuni ta fuskar bambancin.

A gefe guda kuma, yawan buƙatun makamashi da ake buƙata ta buƙatar kiyaye zafin jikinsu akai-akai sananne yana taƙaita iyakokin mu'amalar waɗannan nau'ikan da muhalli. Gabaɗaya, ana la'akari da cewa dabbobin daji suna da tasiri mai yawa akan adadin abin da suke ganimar, wanda a cikin adadi mai yawa akwai sauran nau'ikan dabbobi masu shayarwa, ta yadda a wasu lokuta waɗannan na iya zama tushen abinci na wasu da yawa.

Akwai halittu waɗanda cewa, tare da wasu 'yan mutane, haifar da manyan ƙayyadaddun ƙamus, kamar yadda ya faru da bevolers da kuma yawan samfurori waɗanda ke da matsala, kamar yadda yake al'amarin manyan garken garke na ciyayi ko savannas. Wani abin la'akari na daban shine hulɗar da mutane ke yi akan jimillar da kowane ɗayan halittun, jama'a ko a'a.

Rarraba yanki

Ana daukar dabbobi masu shayarwa a matsayin dabbobin da ke iya yaduwa a kusan dukkan fadin duniya, ban da wuraren sanyi na Antarctica, duk da cewa wasu nau'in hatimi sun mamaye gabar tekun. A gefe guda kuma, wurin da aka rarraba hatimin hispid (Pusa hispida) ya kai ga iyakar Arewacin Pole.

Wata banda shine cewa ya zama tsibiran nesa, nesa da ƙasan ƙasan, inda akwai masifa kawai ta ci, tare da wannan masifa na al'ada wanda ya ƙunsa. A cikin yankunan ƙasa ana samun su daga matakin teku zuwa tsayin mita 6.500, suna mamaye duk abubuwan da suka dace.

Kuma ba kawai a samansa ba, har ma a ƙarƙashinsa, har ma da sama da shi, duka ta hanyar rassan bishiyar kuma sun sami sauye-sauye na jiki wanda ke ba su damar tashi da hankali, kamar yadda ya faru da jemagu, ko kuma a hankali, kamar yadda a cikin al'amarin. na colugos. gliders da squirrels masu tashi.

Haka nan kuma, wadannan dabbobin sun mamaye ruwan. Akwai shaida cewa a ko'ina a duniyar nan, dabbobi masu shayarwa suna zaune a cikin koguna, tafkuna, wuraren dausayi, yankunan bakin teku, tekuna da tekuna inda suka kai zurfin sama da mita 1000. Lalle ne, cetaceans da marine carnivores, biyu daga cikin mafi yadu rarraba kungiyoyin na dabbobi masu shayarwa a duniya.

A matsayin ƙungiyoyin haraji, rodents da jemagu, waɗanda aka ƙara da kasancewa mafi yawa a cikin nau'ikan, sune waɗanda suka mamaye yankuna mafi girma, saboda ban da Antarctica, ana iya kasancewa a duk faɗin duniya, gami da tsibiran da ba su kusa da tsibirin. bakin teku, wanda mulkin mallaka ba shi yiwuwa ga sauran nau'in ƙasa.

A gefe guda, umarni tare da 'yan halittar sune waɗanda aka ƙuntatawa a duniya, musamman da aka ƙuntatawa ga yanki mai iyaka na kudu na Kudancin Amurka, musamman Monito del monte (Dromiciops australis), memba na odar Microbiotheria.

Sirenians, ko da yake tare da ƙuntataccen wurare ga kowane nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i) ana iya samun su a Asiya,Afrika,Amurka ta Tsakiya da Kudancin Amirka da Oceania. Wasu umarni sun keɓanta ga takamaiman nahiyoyi, juyin halittarsu ya keɓanta da sauran dabbobi masu shayarwa, kamar yadda lamarin ya faru a Kudancin Amirka, tubulidentates a Afirka ko kuma dasyuroformes a cikin Oceania, don ba da misalai kaɗan.

Idan muka cire mutum (Homo sapiens), da dabbobin da ke da alaƙa da shi, na gida da na daji, a cikin sauran nau'ikan, watakila kyarkeci mai launin toka ( Canis lupus) ko ja fox (Vulpes vulpes), wanda ya fi yaɗuwa tuni cewa ta ana samun samfurori a mafi yawan yankunan arewa. Hakanan, damisa (Panthera pardus), wanda aka samo daga Afirka zuwa Indiya, ko kuma puma (Puma concolor), daga Kanada zuwa kudancin Patagonia, nau'i biyu ne da ke da wurare masu yawa.

Zaki (Panthera leo), damisa (Panthera tigris) ko launin ruwan kasa bear (Ursus arctos) wasu namun daji ne da suka yadu a yankuna da dama na duniya har zuwa wasu lokuta ko kadan, duk da cewa yankunan da ake rarraba su yana da. a hankali aka rage har sai da ya gutsuttsura ya ƙare ya ɓace daga babban ɓangaren su a yau.

Sabanin haka, adadinsu ya fi girma da yawa suna mamaye filaye masu iyaka kuma ba duka ba saboda an rage su saboda wasu dalilai, amma saboda tsawon tsarin juyin halittarsu ba su iya ko kuma ba a buƙata su faɗaɗa sama da abin da aka mamaye yanzu ba.

Duk da haka, ba wai kawai wasu nau'ikan sun kasance waɗanda suka bace daga yankuna masu faɗin duniya ba, amma wasu rukunin dabbobi masu shayarwa waɗanda a da suka kasance nahiyoyin nahiya ba su iya rayuwa ba sai yau.

Equidae, alal misali, wanda ya kasance yana rayuwa a cikin daji a kusan dukkanin duniya, a yau kawai ya kasance a cikin 'yanci a Asiya da Afirka, wanda mutum ya sake dawo da shi a cikin gida a wasu yankuna na duniya. A daya bangaren kuma, da gangan ko shigar da wasu nau’in halittu a wuraren da babu su, ya sanya nau’in na asali cikin hadari, har ma ya haddasa bacewar su.

Adadin Nau'ukan Kasashe

Babu jimillar nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i) na nau'i-nau'i-nau'i-nau'i-nau'i-na-shawo a duniya:

• Afirka: Jamhuriyar Demokradiyyar Kongo (430), Kenya (376), Kamaru (335), Tanzaniya (359).
• Arewacin Amurka: Mexico (523), Amurka (440), Kanada (193).
• Amurka ta tsakiya: Guatemala (250), Panama (218), Costa Rica (232), Nicaragua (218), Belize (125), El Salvador (135), Honduras (173).
• Kudancin Amirka: Brazil (648), Peru (508), Colombia (442), Venezuela (390), Argentina (374), Ecuador (372), Bolivia (363).
• Asiya: Indonesia (670), China (551), Indiya (412), Malaysia (336), Thailand (311), Burma (294), Vietnam (287).
• Turai: Rasha (300), Turkiyya (116), Ukraine (108).
• Oceania: Australia (349), Papua New Guinea (222).

Dangantaka tsakanin mutane da sauran dabbobi masu shayarwa

Ta hanyar kafa ɗan adam a cikin wannan dabbar dabbar dabbar dabbar da ta fi ƙarfin juyin halitta ta kai shi ga zama mai tunani, ya sami ikon mallakar ba bisa muhallinsa ba amma a kan duk sauran nau'ikan da ke nan. Daga wannan dogaro, jerin hujjoji suna fitowa waɗanda za su iya zama masu ma'ana mai kyau ko mara kyau kuma waɗanda muke magana a ƙasa.

Abubuwan da ba su da kyau

A wasu lokuta, mutane sun yi la'akari da nau'o'in nau'i-nau'i marasa kyau a karkashin bincike mai amfani amma a wasu lokuta yana cikin tsoro mara tushe. Wasu nau'ikan dabbobi masu shayarwa suna cin hatsi, 'ya'yan itatuwa, da sauran tushen shuka, suna cin moriyar amfanin amfanin gonakin ɗan adam don abinci.

A gefensu, ana iya la'akari da masu cin nama a matsayin barazana ga wanzuwar shanu da ma na mutum kansa. Sauran dabbobi masu shayarwa suna rayuwa a cikin birane da kewayen birni suna haifar da wasu matsaloli ga jama'a: hadurran mota, barna da kuma zama marasa amfani da kayan masarufi, ƙwayoyin cuta masu yaduwa da ƙwayoyin cuta, da sauransu. Ya kamata a lura cewa wannan rukunin ya haɗa da namun daji ko na daji da na gida.

Daga cikin dabbobin da za su iya zama misalan yanayi na haƙiƙa ko haɗarin haɗari ga ɗan adam akwai kangaroo a Ostiraliya, raccoons a Arewacin Amurka ko foxes da boars na daji a cikin Bahar Rum na Turai. Bugu da ƙari, wasu nau'ikan dabbobi masu shayarwa, a kai a kai a cikin dangantaka ta kud da kud da mutane, suna da alaƙa ta kud-da-kud da cututtuka irin su rabies, bubonic plague, tarin fuka, toxoplasmosis ko leishmaniasis.

Don haka dole ne mu ƙara da cewa nau'ikan gida, musamman nau'ikan da aka haɗa cikin sabbin halittu, sun haifar da haifar da ingantattun bala'o'in muhalli a cikin flora da fauna na gida, waɗanda ke yin tasiri a kaikaice ba kawai mutane ba, har ma da sauran duniya. jinsunan duniya, dabbobi ne ko tsirrai.

A yawancin tsibiran teku, haɗewar dabbobin gida kamar karnuka ko kuliyoyi, awaki ko tumaki ya nuna jimla ko ɓarna na nau'ikan nau'ikan da yawa.

Bangaskiya masu kyau

Ana ɗaukar dabbobi masu shayarwa a matsayin tushen tattalin arziki mai dacewa ga ɗan adam. An yi amfani da nau'ikan nau'ikan gida da yawa don samun albarkatun da za su ciyar da kansu: madarar shanu, buffalo, awaki da tumaki, naman waɗannan nau'ikan da sauran su kamar naman alade, zomo, doki, capybara da sauran rodents har ma da kare a wasu. yankunan kudu maso gabashin Asiya.

A daya bangaren kuma, mun yi amfani da dabbobi masu shayarwa wajen safara ko ayyukan da ke bukatar karfi ko wasu iyakoki da dan Adam ba shi da su: equidae kamar jaki, doki da nau'insa na alfadari, rakumi irin su llama ko Doki, bovids. irin su sa ko yak, giwar Asiya ko karnukan da suke jan sled, misali ne da za mu iya kawowa.

Duk da haka, kafin a sami wannan fifiko, da alama cewa dabbobi masu shayarwa na asali sun canza zuwa dabbobin dare don guje wa gasa da dinosaur. Kuma yana yiwuwa, don shawo kan sanyi da dare, sun fara haɓaka endothermy, wato, kula da ciki na yanayin jikinsu (wanda aka fi sani da "jini mai dumi"), godiya ga bayyanar Jawo da sebum wanda ke ware. shi (fitowar magudanar ruwa), da kuma zufa na glandon gumi.

Yayin da endothermy ya haɓaka, dabbobi masu shayarwa na farko na gaskiya sun haɓaka dacewarsu da sauran tetrapods na ƙasa, yayin da yawan kuzarin su ya ba su damar jure matsanancin yanayi, girma da sauri, da kuma haifar da ƙarin zuriya. Baya ga kwarangwal na kwarangwal da sauran da aka ambata, kasancewar Jawo da glandan fata, wanda ya ba su fifiko a kan ƙasa tun daga Paleocene, dabbobi masu shayarwa suna nuna wasu siffofi masu ban sha'awa.

Za a iya samun fibers da fata daga sauran dabbobi masu shayarwa don kera tufafi, takalma da sauran kayan aiki: ulun tumaki, alpacas, llamas da awaki, fatan shanun da aka yanka don cinyewa, ko na dabbobin fur da aka yi kiwonsu a zaman talala saboda wannan. manufa, za su iya zama misali.

Sauran dabbobi masu shayarwa sun kasance cikin gida don zama dabbobi, kare ya kasance mafi kusa da mutum a kusan dukkanin duniya kuma ya fi dacewa (kiwo, ceto, tsaro, farauta, nunawa ...). Akwai wasu irin su cat, hamster, pig Guinea, zomo, ferret, ɗan gajeren wutsiya, da wasu primates waɗanda ke cikin dabbobin da ke da mafi girma a duniya.

Farauta wani aiki ne da mutane ke amfana da dabbobi masu shayarwa. Tun daga farkon ɗan adam zuwa yau, farauta ya kasance kuma yana ci gaba da kasancewa tushen abinci mai wuce gona da iri a wasu al'ummomin ɗan adam. Haka nan, wasu dabbobi masu shayarwa suna zama a gida don wasanni ko abubuwan da suka shafi wasa: ayyuka irin su hawan doki sun haɗa da yin amfani da ɗayan nau'ikan dabbobi masu shayarwa waɗanda aka fi sani da girmamawa a kusan dukkanin al'adu da wayewa: doki (Equus caballus) .

Dukansu wuraren shakatawa da na namun daji suma wani shiri ne guda biyu da dan Adam ke cin gajiyar dabbobi masu shayarwa da sauran nau'ikan halittu. Haka kuma wasu dabbobi masu shayarwa na daji suna nufin amfani kai tsaye ga mutum ba tare da ya shiga wani abu ba. A takaice dai, jemagu na da matukar taimako ga kwarin kwari a cikin gonaki ko wuraren da jama'a ke da yawa, ta haka ne kuma ke tsara masu dauke da wasu cututtuka masu yaduwa da cututtuka da za su jefa lafiyar mazauna cikin hadari.

Ajiyewa

A cikin shekaru dari biyar da suka gabata, fiye da nau'ikan nau'ikan nau'ikan nau'ikan 80 sun bace. Yawan wuce gona da iri da ake yi wa kasa, da barnatar da muhalli, da wargajewar yankunan da aka rarraba su ta hanyarsu, hadewar nau'ikan halittu masu ban mamaki da sauran tasirin da dan Adam ke yi na barazana ga dabbobi masu shayarwa a fadin duniya.

A yau, Ƙungiyar Ƙasa ta Duniya don Kare Halittu da Albarkatun Ƙasa (IUCN) ta ƙiyasta cewa kusan ƙarin nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i). Akwai abubuwa da yawa da ke haifar da yuwuwar bacewar nau'in, ciki har da:

• Akwai nau'ikan nau'ikan da ba a saba da su ba ta yanayi, kuma ƙarancin adadin samfuran su shine abin da ya dace na haɗari.
• Hakazalika, waɗanda ke buƙatar manyan yankuna suna fuskantar barazana, a wannan karon saboda asarar wuraren da ba su da alaƙa da kasancewar ɗan adam da rarrabuwar ƙasa, kamar yadda yake a cikin lynx na Iberian.
• Duk wani nau'in da ke da hatsari ga mutane ko kayansu ko kaddarorinsu yana fuskantar barazana sosai ta hanyar tsangwama da tsangwama da ake yi musu, kamar yadda lamarin thylacine yake.
• Ire-iren daji da ake amfani da su a matsayin abinci ko tattalin arziki ta hanyar mutum, a kai a kai a kan matakai masu mahimmanci, misali na wannan su ne whale da karkanda.
• Babu shakka, canjin yanayi da ke canza wurin zama haɗari ne, ba ga dabbobi masu shayarwa kaɗai ba amma ga duk wani abu mai rai a doron ƙasa.

Misalai na Dabbobi masu shayarwa

Dabbobi masu shayarwa jinsuna ne masu rai waɗanda aka siffata saboda mata suna ciyar da ƴaƴansu ta hanyar mammary gland da ke samar da madara. Anan akwai jerin wasu mafi wakilcin dabbobi masu shayarwa na ajin.

Whale: Cetacean ce, wannan dabbar dabba ce wacce ta dace da rayuwa a cikin ruwa. Sabanin kifaye, cetaceans suna da numfashin huhu duk da cewa suna da jiki mai kama da na waccan, tun da duka biyun suna da ilimin halittar jiki na hydrodynamic.

Doki: Wannan dabbar dabbar dabbar perosidactyl ce, wato tana da yatsu masu ban sha'awa waɗanda ke ƙarewa cikin kofato. Ba a samun daidaitawar ƙafafunsa da kofato a cikin wata halitta. Abincin sa yana da ciyawa.

Chimpanzee: Primate na babban kusancin kwayoyin halitta ga mutum, wanda ke nuna cewa jinsin biyu suna da kakanninsu.

Dabbar dolphin: Akwai nau'ikan dolphins na teku da na kogi. Su cetaceans, kamar kifi kifi.

Elephant: Ita ce mafi girma na dabbobi masu shayarwa, wanda nauyinsa zai iya tashi zuwa fiye da ton 7 kuma duk da cewa matsakaicin tsayinsa ya kai mita uku. Wasu giwaye suna rayuwa har shekaru 90. Suna iya sadarwa ta hanyar girgizar da suke samarwa a cikin ƙasa.

Kare: Ko da yake kare ya zama dabbar gida mai mahimmanci, cat ya zauna tare da mutane kimanin shekaru dubu 9 da suka wuce. Suna da ƙwaƙƙwaran ƙima, godiya ga sassauƙar gabobinsu, yin amfani da wutsiyarsu da “right reflex” wanda ke ba su damar juyar da jikinsu cikin iska lokacin da suke saukowa kuma ta haka ko da yaushe suna kan ƙafafu. Saboda tsananin robobin su, suna jure faɗuwa daga manyan tsayi.

Gorilla: Ita ce mafi girma daga cikin primates kuma tana zaune a cikin dazuzzuka na Afirka. Abincinta yana da ciyawa kuma kwayoyin halittarsa ​​sun kasance 97% kama da na mutane. Suna iya kaiwa tsayin mita 1,75 kuma nauyinsu zai iya tashi zuwa kilo 200.

hippopotamus na kowa: Dabbobi masu shayarwa, wato takan kwana a cikin ruwa ko cikin laka sai da magriba takan zo bakin teku domin neman ganyen da za ta ci. Akwai kakanni mai alaƙa tsakanin hippos da cetaceans (Whales, porpoises, da sauransu). Nauyinsu zai iya kai ton uku, amma duk da haka, godiya ga gaɓoɓin gaɓoɓinsu, suna iya gudu da sauri, duk da girman girmansu, kuma cikin gudu irin na ɗan adam.

Raƙumi: Artiodactyl mammal ne, wato, gaɓoɓinta suna da yatsu har ma da lambobi. Mafi yawan kasancewarsa yana a nahiyar Afirka kuma ita ce mafi tsayin dabbobi masu shayarwa, ya kai kusan mita 6. Tana cike da yanayi iri-iri, kamar filayen fili, ciyayi, da buɗaɗɗen daji. An kiyasta cewa tsayinsa wani juyin halitta ne wanda ke ba shi damar isa ga ganyen bishiyar da ke da nisa da sauran dabbobi.

Zakin teku: Dabba ce mai shayarwa ta teku, daga gida daya da hatimi da walruses. Kamar sauran dabbobi masu shayarwa a cikin ruwa, tana da gashin gashi a wasu wuraren jiki, kamar a kusa da baki, da kuma kitse mai dauke da asarar zafi.

León: Feline mammamal da ke zaune a yankin kudu da hamadar sahara da arewa maso yammacin Indiya. Wani nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'in nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i nau'i). Dabba ce mai cin nama, mafarauci da farko na sauran manyan dabbobi masu shayarwa irin su wildebeests, impalas, zebras, baffalo, nilgós, boars daji da barewa. Domin samun abincinsu, waɗannan dabbobin yawanci suna farautar ƙungiyoyi ne.

Batir: An san su a matsayin kawai dabbobi masu shayarwa waɗanda ke da ikon tashi.

otters: Masu shayarwa masu shayarwa waɗanda ke zama a cikin ruwa, amma ba su rasa gashin su kamar sauran dabbobi masu shayarwa na ruwa. Abincinsu ya dogara ne akan kifi, tsuntsaye, kwadi da kaguwa.

Platypus: Monotreme, wannan yana ɗaya daga cikin ƴan dabbobi masu shayarwa (kamar echidnas) waɗanda ke yin ƙwai. Yana da guba da ban sha'awa saboda kamanninsa, tunda duk da cewa jikinsa yana lulluɓe da gashi kamar yawancin dabbobi masu shayarwa, yana da kwarjini mai kama da bakin agwagi. Kasancewarsa an san shi ne kawai a gabashin Ostiraliya da kuma a tsibirin Tasmania.

Belar Bear: Ana ɗaukarsa ɗaya daga cikin manyan dabbobi masu shayarwa a ƙasar. Tana zaune ne a yankunan sanyi na yankin arewaci. Jikinta ya dace da ƙananan zafin jiki na godiya ga nau'ikan gashi da mai.

Rhino: Su dabbobi masu shayarwa ne da ke zaune a Afirka da Asiya. Ana iya gane su da sauƙi ta ƙaho a kan hancinsu.

Dan Adam: Mutane suna daga cikin nau'in dabbobi masu shayarwa kuma yawancin dabi'u na gaba ɗaya suna da alaƙa da mutane. Gashin jikin ɗan adam shine yanayin juyin halitta na gashin wasu birai.

Taigiris: Feline mammamal da ke zaune a nahiyar Asiya. Mummunan mafarauci ne, ba wai kawai na dabbobi masu shayarwa da tsuntsaye ba, har ma da sauran namun daji irin su kerkeci, kuraye da kada.

Zorro: Masu shayarwa yawanci zaman kadaici. Glandan mammary ɗinsu sun yi yawa. A matsayin wani ɓangare na harinsa da tsarin tsaro, yana da babban ji da kuma ingantaccen hangen nesa don gani a cikin duhu.

Dog: Wani nau'in tsari ne na wolf, na dangin canidae. An san fiye da nau'in karnuka 800, wanda a fili ya wuce kowane nau'in. Kowane iri-iri yana da sanannen bambance-bambance a cikin dukkan halayensa, daga gashi da girma zuwa ɗabi'a da tsawon rayuwa.

Sauran misalan dabbobi masu shayarwa sune: Almiquí, Koala, Alpaca, Damisa, Squirrel, Llama, Armadillo, Raccoon, Kangaroo, Porpoise, Alade, Orca, Deer, Grizzly Bear, Coati, Anteater, Weasel, Tumaki, Zomo, Panda, Iblis na Tasmanian. , Panther, Seal, Bera, Cheetah, Mouse, Hyena, Mole, Jaguar, saniya, da dai sauransu.

Nasarar Juyin Halitta na Dabbobin Mammali

Binciken burbushin halittu a cikin 'yan kwanakin nan ya nuna cewa, kafin meteorite ya kawo karshen rayuwa da rinjayen dinosaur, dabbobi masu shayarwa sun riga sun kafa harsashin rinjayensu na gaba a duniya. Masu bincike sau da yawa suna mamakin yaushe da kuma yadda dabbobi masu shayarwa suka zama ƙwararrun kashin baya. Duk da haka, har zuwa lokacin ba a sami isassun burbushin halittu a wannan fanni ba.

A cikin shekaru 15 na baya-bayan nan an sami ci gaba na binciken da suka ba da bayanai game da bambance-bambancen da cin nasarar wannan ajin da suka fayyace rawar da bacewar dinosaurs ta taka. Irin wannan binciken ya nuna cewa dabbobi masu shayarwa sun samo asali ne tun da wuri fiye da yadda ake zato kuma sun ɓullo da nau'o'in ƙwarewa a lokacin mulkin dinosaur. Bacewar dinosaur ba zato ba tsammani ya share hanya ga dabbobi masu shayarwa.

A wani maraice na hunturu a farkon 1824, masanin Ingilishi kuma masanin tauhidi William Buckland ya yi jawabi ga Ƙungiyar Geological Society ta London. Dakin ya hargitse da jiransa. Buckland ya shahara ne da lakcocin da ya yi a Jami’ar Oxford, inda aka ce, sanye da duk kayan sa na ilimi, zai ba da sassan dabbobi da burbushin halittu a tsakanin dalibansa masu himma.

Shekaru da dama ana ta yada jita-jitar cewa tana dauke da kasusuwan kasusuwan kasusuwan kasusuwa, wadanda masu yin duwatsu suka gano a cikin karkarar Ingila. Bayan kusan shekaru goma na nazari, ya shirya ya sake shi a fili. Ya shaida wa mahalarta taron cewa wadancan kasusuwan wani bangare ne na dabba mai nisa irin na kadangaru amma sun girmi duk wani dabba mai rarrafe a yau, wanda ya kira Megalosaurus. Jama'a sun nutsu. Buckland ya gabatar da dinosaur na farko.

Faɗuwar faɗuwar rana ta kasance wani muhimmin lokaci a tarihin kimiyya, wanda ya haifar da sha'awar dinosaur da ke ci gaba har wa yau. Amma abin da ake son a manta da shi shi ne cewa a wannan rana Buckland ya sake yin wani wahayi; mafi ƙanƙanta girma, amma daidai da juyin juya hali. Ta hanyar nazarin sauran burbushin halittu da aka samu tare da megalosaurus a cikin littafin, ya yi nazarin binciken "abin ban mamaki" na tsummoki na dabbobi masu shayarwa guda biyu, kama da girman muƙamuƙin linzamin kwamfuta.

Har ya zuwa yanzu, masana sun yi la'akari da dabbobi masu shayarwa a matsayin kwanan baya kuma sun fito da yawa daga baya akan ma'aunin yanayin kasa, bayan raguwar kadangaru da manyan salamanders. Ƙananan muƙamuƙi guda biyu suna da kyan gani na dabbobi masu shayarwa kuma sune farkon alamar cewa tarihin wannan ajin ya tsufa sosai.

Waɗancan ƴan hancin sun gabatar da wasan wasan wasan caca: Shekara nawa ne dabbobi masu shayarwa? Menene suke so kuma ta yaya suka gudanar da rayuwa ta hanyar dogon lokaci na dinosaur? Ta yaya siffofinta (fata, glandan mammary, babbar kwakwalwa, hadadden haƙora, da haɓakar hankali) suka fito? Kuma me ya sa daya rukuni, na placentals, da aka sani da haihuwa mafi ci gaba zuriya da kuma a yau ya ƙunshi fiye da 5.000 nau'i, daga kananan jemagu zuwa manya manyan Whales, suka iya cinye duniya?

Kusan ƙarni biyu bayan taron Buckland, waɗannan tambayoyin sun ci gaba da zama da wahala a amsa, idan aka yi la'akari da ƙarancin adadin burbushin waɗannan dabbobi masu shayarwa na farko. Amma a cikin shekaru goma sha biyar da suka gabata an sami binciken burbushin halittu da yawa wanda, bayan haka, yana ba da damar tantance juyin halittarsa, daga ƙananan ƙwayoyin cuta da ke zaune a cikin inuwar megalosaurus zuwa yanayin ban mamaki na yau.

Farkon Tawali'u

Kamar dauloli da yawa, dabbobi masu shayarwa sun samo asali ne daga shimfiɗar jariri. A cikin ilimin kimiyya, a cikin tsarin tsarin bishiyar rayuwa, nau'in dabbobi masu shayarwa sun hada da monotremes (oviparous), marsupials (dauke da kananan yara a cikin jaka), da placentals, da dukan zuriya, yanzu bace, na magabata na kowa.

Dabbobin farko da kamanninsu da halayensu suka yi kama da na dabbobi masu shayarwa na zamani, rukuni ne daban-daban da ake kira mamaliaforms, sunan da ya dace da dangi na kusa da dabbobi masu shayarwa na gaske. Sun zo daga cynodonts, nau'ikan da suka dace waɗanda suka kiyaye kyawawan abubuwa da yawa na Reprian.

Asalin Kwakwalwar Mammaliya

Ingantacciyar ma'anar wari da taɓawa na iya tuntuɓar juyin halittar kwakwalwar dabbobi masu shayarwa. Binciken burbushin burbushin cranial na dabbobi kafin farawar dabbobi masu shayarwa ya nuna cewa wuraren da ke da alaƙa da ƙwaƙwalwa da wari da taɓawa, da kuma daidaitawar neuromuscular, sun haɓaka juyin halittar kwakwalwa a tafarkin juyin halitta wanda ya haifar da dabbobi masu shayarwa.

An gudanar da gwaje-gwajen burbushin halittu daga kimanin shekaru miliyan 190 da suka gabata, musamman na Morganucodon da Hadrocodium, kakannin dabbobi masu shayarwa, da aka samu daga kasusuwan kasusuwa na Jurassic a kasar Sin. Dukansu suna da girma fiye da yadda ake tsammani don samfurori na lokacinsu da kuma daidai da yawan jikinsu.

Ko da yake an yi nazarin fasalin waje na kwanyar waɗannan nau'ikan da suka mutu shekaru da yawa, ba a san fasalinsu na ciki ba. Ta hanyar high-resolution kwamfuta axial tomography (CAT), masu bincike yanzu sun sami damar ƙirƙirar kwatancin kwakwalwar da suka ajiye. Kungiyar CT ta yi daidai da CT na burbushin halittu na fossils na 12, gami da Cynandonts, da farkon dabbobi masu shayarwa na yau da kullun.

Dangane da irin wannan kwatancen, an tabbatar da cewa, a cikin Morganucodon da Hadrocodium, saman kwakwalwar da ke jagorantar ji na wari da tabawa, da kuma daidaitawar neuromuscular, sun sami ci gaba fiye da sauran kwakwalwa. Kasancewar ingantacciyar ma'anar wari da taɓawa na iya zama kayan aiki don taimakawa dabbobi masu shayarwa su tsira da bunƙasa a farkon matakin tarihin juyin halittar mu.

Dabbobin dabbobi masu shayarwa da suka bace daga Kudancin Amurka

Kasusuwan da aka gano kwanan nan a cikin Andes na Chile suna magana ne game da dabbobi masu shayarwa na musamman waɗanda suka taɓa yawo a Kudancin Amurka. Irin waɗannan binciken suna tarwatsa ra'ayoyin da ake dasu game da abubuwan da ke faruwa a fannin ƙasa a nahiyar.
 
A gefen wani faffadan ciyayi, masu kofato, dawakai irin na ciyawa, da wani abu mai kama da tururuwa, da ramin kasa, a natse suke ci, ba tare da damuwa da barazanar da ke jiransu ba. Har ila yau, sun shanye su ne chinchilla da wata ƙaramar linzamin kwamfuta-kamar marsupial nibbling akan tsaba a kusa.

Nan da nan, bala'i ya afku: ɗaya daga cikin tsage-tsatse, dutsen mai dusar ƙanƙara a sararin sama ya barke. An jefar da ƙoramar toka mai kauri a gangaren gangariyarsa. Wani lokaci daga baya, gajimaren gizagizai ya mamaye filayen ya binne dabbobin da ba a ji ba a hanya.

Ga dabbobin da aka binne, wannan kogin mai aman wuta ya kasance bala'i. Ga ilimin burbushin halittu, da bambanci, zai zama sa'a. Dubun milyoyin shekaru bayan mutuwar wadancan dabbobi masu shayarwa da wuri, karfin hakowar orogenesis da zaizayar da suka biyo baya ya bankado ragowar kasusuwan burbushinsu a cikin Andes na tsakiyar kasar Chile.

An gano su ne a shekara ta 1988, yayin da ake neman alamun dinosaur a wani tudu na kogin Tinguiririca, kusa da kan iyaka da Argentina. Binciken ya yi matukar amfani, tun daga wannan lokacin ake mayar da yankin a duk shekara don ci gaba da nazarin gawarwakin. Ya zuwa yanzu, an gano sama da burbushin tsofaffin dabbobi masu shayarwa 1.500 a wurare da dama na burbushin halittu a tsakiyar Andes na kasar Chile.

Sauran labaran da ka iya sha'awar su ne:

• Dabbobin ruwa
• Dabbobin ƙasa