| http://www.bbc.com/earth/story/20160812-why-we-have-a-spine-when-over-90-of-animals-dont
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http://www.bbc.com/hausa/mujalla/vert_earth/2016/08/160825_verticals_earth_why_we_have_spine_when_most_animals_dont
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| why we have a spine, when over 90% of animals don't
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me ya sa mafi yawan dabbobi ba su da kashin baya?
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| 15 august 2016 by josh gabbatiss
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25 agusta 2016
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| although the backbone is one of the most important innovations in the history of life, its origins have long been shrouded in mystery.
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koda yake kashin baya na daga cikin muhimman kirkire-kirkire a tarihin halitta, kawo yanzu an kasa tantance asalinsa.
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| a popular trope of science fiction
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mafi yawan finafinan da ke kokarin nuna wata duniya ta daban,
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| is a world in which creatures with unusual body plans rule.
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kan nuna halittu ne masu tsarin halitta bambarakwai.
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| from the octopoid martians of war of the worlds
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kama daga halittun duniyar mars masu kama da kaguwa a fim din war of the worlds
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| to the giant "bugs" of starship troopers,
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zuwa ga manyan kwarin starship troopers,
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| there is a creepy appeal in the idea that a race of spineless creatures could pose a real threat to humanity.
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masu shirya finafinan kan nuna cewa halittu mara sa kashin baya na iya zama barazana ga jinsin mutane.
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| because as far as we are concerned,
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saboda mu a ganinmu
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| the backbone is king.
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kashin baya shi ne gaba da komai.
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| whether or not we are truly the "dominant" organisms on earth is debatable.
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duk da dai ba tabbas cewa mu ne halittar da tafi kowacce iko a duniya,
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| but we are vertebrates –
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amma dai muna da kashin baya,
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| and so are most of the large, charismatic animals that walk,
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haka kuma sauran manyan dabbobi masu kwarjini, wadanda ke tafiya,
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| swim
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ninkaya
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| and fly.
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ko tashi duk su na da kashin baya.
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| it is only natural that we find ourselves drawn to what henry gee,
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don haka ba mamaki idan mu ka bi abinda henry gee,
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| senior editor at nature, calls
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babban edita a mujallar nature ke kira
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| our own corner of creation.
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“fifita dangin halittarmu”.
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| the spine is certainly a useful innovation.
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tabbas kashin baya, gaba ce mai matukar amfani.
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| it provides support for the body,
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ta na tallafawa jiki,
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| as well as valuable protection for the spinal cord.
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tare da samar da cikakkiyar kariya ga laka.
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| the fact that our bodies are supported by an internal skeleton as opposed to an external one also allows for a greater range of movement,
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haka kuma samun kasusuwa a cikin jikinmu maimakon a waje ya bamu damar motsi iri-iri,
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| and means vertebrates can grow to far greater sizes than any invertebrate ever has.
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baya ga cewa dabbobi masu kashin baya na iya girman da babu wata dabba mara kashin baya da za ta taba kai wa.
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| but seeing as over 90% of all animals get by just fine
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sai kuma ganin cewa fiye da kaso 90% na dabbobin duniya na rayuwa ne
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| without backbones,
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ba tare da kashin baya ba,
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| it is not obvious why this novelty arose in the first place.
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babu wani tartibin bayani na dalilin bullar wannan halitta a karo na farko.
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| how did the spine emerge from a spineless world?
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yaya aka yi kashin baya ya bulla a duniyar da a da babu kashin bayan?
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| the evolutionary leap that birthed the vertebrates took place during the cambrian period
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dabbobi masu kashin baya dai sun bayyana a duniya ne
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| around 500 million years ago.
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kimanin shekaru miliyan 500 da su ka wuce.
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| prior to this,
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kafin wannan zamanin,
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| life had been a pretty simple affair
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halittu na gudanar da sassaukar rayuwa ne
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| for hundreds of millions of years;
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tsawon daruruwan miliyoyin shekaru;
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| single cells drifted around,
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mafi yawansu kwayar halitta daya kurum ke watangaririya cikin teku,
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| occasionally getting together to form a colony.
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in ta yi kamari sai wadannan kwayoyin halittun sun cure wuri guda.
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| that was pretty much it.
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shi ke nan.
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| then, boom!
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kwatsam!
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| in an event known as the cambrian explosion,
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sai aka wayi gari
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| earth's oceans were filled with a huge array of life forms.
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tekunan duniya na cike da wasu sababbin nau’o’in halitta.
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| within a few tens of millions of years
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cikin miliyoyin shekaru kadan
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| something new joined the ranks of the six-foot predatory arthropods and multi-eyed oddities.
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sai wata bakuwar halitta ta biyo sahun kwari da tsutsotsi.
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| animals that looked something like today's lampreys and hagfish.
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wato dabbobi masu kama da kifi-kifi, maciji-maciji.
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| these creatures were some of the first vertebrates.
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wadannan dabbobin su ne masu kashin baya na farko.
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| the notochord was the precursor to the backbone,
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sai dai kahsin bayan nasu na kaya ne ba na kashi ba.
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| the structure found in vertebrates from mice
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daga nan ya zama kashi irin wanda ake samu a halittun da su ka kama daga beraye,
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| to dinosaurs
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zuwa kakannin kadangaru,
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| to humans.
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zuwa ga mutane.
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| we know where these first vertebrates came from.
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mun san inda wadannan halittun su ka fara bayyana.
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| their predecessors are represented by fossils from those cambrian seas:
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an samu kwarangwal din kakannninsu a karkashin teku:
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| worm-like animals like pikaia and haikouella.
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wasu dabbobi masu kama da tsutsoti.
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| these animals are not vertebrates,
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su ba su da kashin baya
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| but they do possess a notochord.
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amma su na da kaya.
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| they belong in a more inclusive category called the chordates, which incorporates vertebrates and a few vertebrate-like groups.
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wannan ne ya sa mu kan mu kan fara da kayar baya ne kafin ta zama kashi a lokacin da muna ‘yan tayi.
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| but the question of exactly where those first chordates came from has long proved controversial.
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sai dai kuma su wadancan halittun masu kaya daga ina su ka bullo?
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| in 1909, the golden jubilee of darwin's on the origin of species,
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a 1909, shekaru hamsin bayan wallafa littafin asalin halittu na charles darwin,
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| the linnean society of london organised an event to explore the origin of the vertebrates.
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wata kungiyar masana a london ta hada taron tattaunawa da nufin gano asalin dabbobi masu kashin baya.
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| it was not a rousing success:
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ba su sami nasara ba:
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| the disputants agreed on one single point,
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“masanan sun amince da abu daya ne kawai,”
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| quipped zoologist thomas stebbing:
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in ji masanin dabbobi thomas stebbing:
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| namely, that their opponents were all in the wrong.
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“wato, abokan jidalinsu sun tafka kuskure.”
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| over the years,
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a tsawon shekarun da su ka gabata
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| virtually every invertebrate group – from molluscs to arthropods – has been suggested as a starting point for the origin of the chordates.
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an danganta asalin dabbobi masu kashin baya da kusan kowanne dangi na dabbobi mara sa kashin baya,
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| the fossil evidence to reliably answer the question is lacking.
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sai dai har yanzu an kasa samun gamsasshiyar hujja.
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| this is because unlike later vertebrates,
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wannan kuwa ya faru ne saboda sabanin dabbobi masu kashin baya,
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| which are full of hard, "fossilisable" components like bones and teeth, these early creatures were too squishy to leave much lasting evidence.
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wadanda ke da kwarangwal da hakoran da ke wanzuwa shekaru aru-aru, wadannan halittun su kan zagwanye ne gaba daya su zama kasa.
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| today, only faded imprints of their soft bodies remain.
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babu abinda ya rage a yanzu sai shatar jikinsu a duwatsun karkashin teku.
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| that said, in the past few decades
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sai dai a baya bayan nan,
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| the fields of evolutionary developmental ("evo-devo") biology and molecular phylogenetics
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masana kimiyyar samuwar halittu
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| have given scientists a much better understanding of the evolutionary relationships between organisms.
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sun bullo da wata hanyar gano asalin inda kashin baya ya bulla.
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| this has included the finding that some of our closest invertebrate relatives are
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masanan sun ce muna da dangantaka ta kusa da wasu
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| a group of marine animals
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dabbobin ruwa
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| that includes the familiar starfish, sea urchins and sea cucumbers, as well as some unusual worm-like animals called the hemichordates. like all of these animals, we are deuterostomes – meaning that during embryo development, our anus forms before our mouth.
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da kuma tsutsotsi saboda a lokacin da muke ‘yan tayi, muna fara samun kofar kashi kafin mu samu baki.
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| this means that we are, ultimately, defined by our anus, which is a bit humbling.
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wato ke nan dai ta-kashinmu ita ce siffar da ake amfani da ita wurin gano dangantakarmu.
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| though we appear to look nothing like sea urchins and their ilk, we do share a common ancestor,
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koda yake babu wata kama da muka yi ta zahiri da wadancan dabbobin ruwan da tsutsotsi, alamu na nuna cewa kakanninmu daya,
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| which according to linda holland,
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wadanda linda holland,
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| a chordate researcher at the scripps institution of oceanography, usa,
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mai nazarin dabbobi a cibiyar binciken ilimin teku ta scripps da ke amurka ke cewa
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| could have looked sea urchin-like, chordate-like, hemichordate-like -
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za su iya yin kama da tsutsa, ko dabbar ruwan
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| or like none of these.
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ko kuma kamarsu dabam.
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| then, one of those early deuterostomes became the very first chordate by gaining a notochord.
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daga cikin dangin dabbobin da kan fara yin kofar kashi kafin baki, a lokacin da su na ‘yan tayi ne aka samu wani da ya fara yin kaya.
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| nori satoh, a researcher at the okinawa institute of science and technology in japan,
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nori satoh, mai bincike a cibiyar kimiyya da fasaha ta okinawa, japan
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| has identified what he sees as the moment the notochord, and hence the chordate lineage, was born.
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ya ce ya gano lokacin da aka fara samun dabba mai kayar baya.
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| i have proposed that the occurrence of tadpole-like larvae is a key event that caused the evolution of chordates, he explains.
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ya ce: “ina ganin samuwar halittu masu yanayin talibamban ne asalin fara samun dabbobi masu kayar baya.”
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| early in life,
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a farkon rayuwarsu,
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| many deuterostomes pass through a larval stage. but while acorn worm or sea urchin larvae might swim about by rhythmically moving tiny hair-like structures – cilia – on their bodies, chordate larvae have a tail that they beat.
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dabbobin da kofar kashi kan riga baki fitowa lokacin su na ‘yan tayi, kan sauya daga kwai zuwa wata halitta mai kamar tsutsa, yayinda wasu daga cikinsu ke da wasu irin kananan gasu da ke taimakonsu ninkaya a ruwa, dabbobi masu kayar baya na da jela ne. don haka satoh ya ce: “kayar ta bullo ne domin ta ba su damar buga jelar yayin iyo.”
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| the notochord is the supporting organ of the beating tail, says satoh.
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bayan shudewar zamani ne sai tsarin jikin dabbobi masu kayar baya ya fara sauya kadan-kadan.
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| satoh thinks this is obvious. "swimming with a beating tail is much more efficient than locomotion with ciliary beats," he says. "the notochord gave the earliest chordates a unique advantage."
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a cewar holland: “ina ganin garin girman jikin dabbobin ne ya sa su ka fara bukatar wata gabar wacce tafi kaya kwari wurin yin iyo a ruwa.”
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| from our perspective, it is easy to see the later evolution of the vertebrates as a march of progress: early vertebrates gave way to fish, which gained legs
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a yanzu sai mu ga cewa sassauyawar halitta daga kakannin kakanninmu masu kayar baya, zuwa kifaye,
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| and became four-legged land animals,
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zuwa ga dabbobin tudu masu kafafu hudu,
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| which eventually began walking on two legs and became human.
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wanda daga bisani suka mike tsaye su ka zama mutane wani abu ne dake nuna ci gaban halittu.
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| but viewing vertebrate history as a straightforward progression from humble origins to humanity is misleading.
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sai dai kuskure ne mu dauka cewa tarihin sassauyawar halittu ya faru ne kai tsaye.
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| when researchers
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lokacin da masu bincike
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| at the european molecular biology laboratory
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a cibiyar nazarin halittu ta nahiyar turai
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| found a notochord-like structure in a marine worm back in 2014,
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su ka gano wata tsutar teku a 2014 mai kayar baya,
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| it supported an old theory of how chordates originated from ancient worms.
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sai su ka rike ta a matsayin hujjar ra’ayin da ke ganin dabbobi masu kaya sun samo asali ne daga tsutsotsi.
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| intriguingly, it also suggested just how wrong our march of progress image really is.
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wannan ya nuna cewa ba kai tsaye halittu kan sauya daki-daki kamar yadda muka dauka a baya ba.
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| the appearance of the notochord might not have been a seminal turning point in the history of life after all.
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mai yiwuwa ne ma tun tuni kakannin kakannin kakanninmu su ka fara yin kaya amma daga bisani su ka yi watsi da ita da su ka fahimci cewa babu wani amfani da za ta yi musu a rayuwarsu ta karkashin teku.
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| sci-fi depictions of invertebrate supremacy may be a little off the mark, but numerically at least, our world is dominated by creatures that to us seem simple.
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ashe ke nan finafinan da ke nuna daukakar dabbobi masu kaya kan mara sa kaya sun kauce hanya, tun da akalla ko dai a yawan adadi, dabbobi marasa kashin baya sun fi masu kashin bayan.
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| some even lack many of the traits we would associate with animals, such as mobility or a head.
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wasunsu ma ba su da dabi’o’in da muke dangantawa da dabbobi irin su motsi ko kuma mallakar kai.
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| evolution has no end point.
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sassauyawar halittu ba shi da magaryar tukewa.
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| there is no ideal that it is striving towards.
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babu wani mataki da halittu ke kokarin kai wa.
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| a starfish is as highly-evolved as a human,
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kifin da ke cikin ruwa daidai ya ke da dan adam a cikar halittarsa,
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| and the fact that an ancestral starfish may have shed some of the traits we associate with sophisticated body forms demonstrates the absence of innate vertebrate superiority.
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kuma idan har shekaru aru-aru kafin samuwar mutane, wadansu kifayen sun yi amfani da kashin baya kuma sun yi watsi da shi, ashe ke nan babu wata daukaka da ta rataya ga mallakar kashin baya.
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| so remember,
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don haka a kula,
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| there is nothing wrong with being spineless.
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babu wani ci baya a kasancewa dabba mara kashin baya.
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