Koj yuav xav tsis thoob thaum kawm tias sharks laus dua ntoo raws li lawv tau nyob ib puag ncig tsawg kawg 400 lab xyoo. … Qhov ntxov tshaj plaws shark hniav yog los ntawm thaum ntxov Devonian deposits, ib co 400 lab xyoo, nyob rau hauv niaj hnub no yog Europe.
Puas muaj sharks ua ntej ntoo?
Zoo qhov tseeb ntawm hnub: Sharks yog laus dua ntoo. Cov tsiaj ntxov tshaj plaws uas peb tuaj yeem faib ua "ntoo," uas tam sim no-tuag Archaeopteris, nyob ib puag ncig 350 lab xyoo dhau los, hauv hav zoov uas tam sim no Sahara suab puam.
Yuav ua li cas thawj shark lossis tsob ntoo?
Sharks tau nyob ib puag ncig ntau pua lab xyoo, tshwm sim hauv cov ntaub ntawv fossil ua ntej ntoo txawm muaj.
Puas yog Sharks laus dua ntoo?
Sharks yog laus dua ntoo Sharks muaj ntau dua 450 lab xyoo, qhov tsob ntoo ntxov tshaj plaws, nyob ib puag ncig 350 lab xyoo dhau los. Tsis tsuas yog sharks laus dua ntoo, tab sis lawv kuj yog ib qho ntawm cov tsiaj xwb uas tau muaj sia nyob plaub ntawm tsib qhov kev ploj tuag - tam sim no yog qhov txaus nyiam.
Sharks hloov zuj zus los ntawm dab tsi?
xav tias lawv nqis los ntawm ib tug me me nplooj-zoo li ntses uas tsis muaj qhov muag, fins lossis pob txha. Cov ntses no ces hloov zuj zus mus rau 2 pawg ntses loj uas pom niaj hnub no. Bony ntses (Osteichthyes) thiab ntses cartilaginous (Chondrichthyes - sharks, skates, rays thiab chimaera).
