Ib tug dej dais. Hom me invertebrates

Nyob rau hauv cov xwm, muaj ib tug tshwj xeeb creation, khwv tau lub npe menyuam yaus "dej Xyooj". Me-paub (tshwj tsis yog rau zoologists thiab cov kws txawj rau qhov chaw), paub cov neeg thiab nws muaj feem xyuam rau lawv cov tsos, thiab lawv survivability. Thawj zaug lub npe rau tau txais kom meej meej zoo sib thooj nrog cov khaub noom los yog ib tug teddy dais. Txawm li cas los, nws muaj rau ob txhais ceg, thiab "ntsej muag" zoo nkauj yooj yim rau hu, tab sis tsis kom meej meej traceable. A "dej" tus dais vim hais tias nws yog tus neeg ntawm cov ib puag ncig thiab ua neej nyob tsis muaj noo noo (nyob rau hauv lub literal siab ntawm lo lus) tsis tau.

Keeb kwm ntawm foundations

Muaj yog vim li cas rau pov plob hais tias dej bears, tardigrades twb precisely cov creatures, uas pom tus creator ntawm Van Levenguk tshuab kuaj kab mob raws li thaum ntxov raws li 1702. Txawm li cas los, cov thawj nom foundations ntawm cov oldtimers yog 1773, thaum lawv piav txog tus German xibhwb Gotse. Ceeb lawv cov tsos, nws muab lawv lub npe kleiner wasserbär, uas translates los ntawm German raws li ib tug me me (me me) ib tug dej dais. Ntau nthuav dav me me creatures tau raug kawm thiab piav los ntawm lub Italian biologist Lazzaro Spallanzani, thiab nws tshwm sim nyob rau hauv 1776. Vim lub qeeb heev muaj ntawm cov tsiaj, nws lub npe hu lawv il tardigrado, ua nyob rau hauv lub official scientific lub npe los ua lub sij hawm Tardigrada, piv txwv li Tardigrada.

Qauv dej Xyooj

Tus thawj tshaj plaws kom koj nco ntsoov thaum kawm Tardigrada - luaj li cas ntawm cov tsiaj. Hom ntawm marine Dais muaj txog 960, thiab tus nqi ntawm lawv lub cev yog hom twg los ntawm 0.1 rau ib tug thiab ib tug ib nrab millimeters. Txawm cov coob tshem me me xav txog tsis muaj ib tug tshuab kuaj kab mob yog heev yooj yim. Tardigrades chav kawm ntawv muaj nyob rau hauv invertebrates muaj steklistoe, translucent lub cev, visually tawg mus rau hauv 4 theem constrictions. Vim muaj cov chitinous plhaub thiab periodic shedding dej Xyooj tej zaum piv nrog kab. Feem ntau cov hom yog tam sim no plaub officers ntawm ob txhais ceg, tab sis yog ib lub me me "pob zeb", ib tug ntev ntawm xwb ib feem kaum ntawm ib millimeter, yog ib tug kos: nws yog ib tug rau-legged-Tardigrada. Txhua ceg xaus nrog claws nyob rau hauv lub xov tooj ntawm 4-6 daim. Qhov kawg khub ntawm ob txhais ceg yog qhia rov qab.

"Tus Neeg" los yog txawv heev thiab reminiscent ntawm ib plua plav collector ntawm lub tshuab nqus tsev nqus tsev vacuum. Roth yog txawm peem rau nrog ib co tsi stiletto, uas dais cov dej penetrates ntawm daim tawv nqaij khoom noj khoom haus. Cov tsiaj muaj lub paj hlwb, digestive, deev thiab tshee systems, tab sis tsis muaj lub plawv thiab ua pa. Es tsis txhob ntawm cov ntshav ntawm lub tag nrho lub cev muaj kab noj hniav occupies ib tug tshwj xeeb cov kua, thiab ua tsis taus pa tardigrades daim tawv nqaij. Lawv muaj ntxiv tactile kabmob raws li ib tug khub ntawm appendages, thiab, oddly txaus, lub qhov muag, uas yog tsuas yog tsaus me ntsis rau ntawm lub cev nyob rau hauv pem hauv ntej, tab sis tsis nyob rau ntawm qhov chaw, uas muaj peev xwm yuav hu ua lub taub hau.

Ib tug dej dais ib cov xim, nyob ntawm seb cov ib puag ncig tej yam kev mob. Hawj txawm tej zaum yuav nyob rau hauv ib tug ntau ntawm cov xim txiv kab ntxwv - liab los yog txiv - tsaus ntsuab.

Tardigrades txawv sexes, tab sis caug yog ntau npaum li cas tsawg tshaj cov poj niam, li ntawd, ntau yam ntaub ntawv teev tus neeg mob ntawm parthenogenesis (tu tub tu kiv tsis muaj fertilization).

Tardigrades yog kis tau thoob lub ntiaj teb no los ntawm cov tropics rau lub Arctic vajvoog. Txawm li cas los, yog hais tias lawv xaiv, lawv xav ntub Lichens thiab mosses. Faib nyob rau hauv dej dais passive: tus neeg tsiv vim cov cua los yog cov dej ntws, thiab kuj kis mus rau rov noog thiab plaub tsiaj.

hwj chim nta

Dej bears yog tardigrades, feem ntau ntawm lawv nyob rau cov nuj nqis ntawm mosses, me me algae thiab cov kab mob. Peb dej hiav txwv hom cab tsuas yog nyob rau shellfish, loj dej invertebrates thiab hiav txwv dib. Hais txog ib nrab ib kaum os cov tsiaj ntawm dej bears - ncaj txhom, nyob rau hauv ib tug noj cov zaub mov uas muaj micro-kab thiab roundworms; xws Tardigrada txaus ntshai txawm lawv tus kheej cov khub - noj rau nws txhua txhua hnub ua lag ua luam.

unkillable zeej

Feem ntau cov zaum xav nyob rau hauv cov dej dais nws kev loj hlob. Tej no kuj yog muaj peev xwm cawm tau lawv lub neej thiab lub peev xwm los loj hlob nyob rau hauv ib tug ntau ntau yam kub - los ntawm meej pes tsawg (-273 degrees) mus rau lub unbearable tshav kub nyob rau hauv lub 150. Lawv ciaj sia nyob rau hauv hostile ib puag ncig, xws li nyob rau hauv ib tug hydrogen sulfide cua. Tawg no kuj yog rau lawv tsis yog ib qho yuav kho teeb meem kom ciaj sia taus: tom qab nws irradiation ntawm ib koob tshuaj 570.000 X-ray ib nrab dej bears dim. Rau siv: cov rau tib neeg yog tawg "tsuas" 500 X-rays. Thiab tardigrades dim tseem yuav muab (thiab muab) offspring.

qhov chaw stability

Feem ntau ntawm tag nrho cov, cov kev zej zog xav nyob rau hauv lub peev xwm Tardigrada mas qhov chaw tej yam kev mob. Nyob rau hauv 2008, ib tug pab neeg tshawb fawb coj los ecologist Swede Ingmar Jonsson xa mus rau hauv lub ntiaj teb orbit sim batch ntawm tardigrades. Ib pab pawg neeg twb muab tso rau hauv ib lub tshuab nqus, lub thib ob ib txhij irradiated nrog tawg, lub ob tau raug kev mob siab heev ultraviolet lub teeb kev kho mob. Cov kev kawm nyob rau hauv lub qhib qhov chaw peb nyob 10 hnub thiab yuav luag tsis muaj kev zam tau seared. Txawm li cas los, nyob rau nws rov qab mus rau ntau paaj tej yam kev mob feem ntau ntawm cov me creatures rov qab mus rau lub neej, thaum cov lus muaj peev xwm rau cov me nyuam.

Lub hauv paus ntawm cov ciaj sia taus

Muaj peev xwm, los ntawm kev uas dej yuav mus dais xws li ib tug ntau yam ntawm kev phiv tej yam kev mob - lub peev xwm los mus rau hauv hibernation los ntawm tej tshuaj anhydrobiosis. Nyob rau hauv lwm yam lus, Tardigrada dries nws tus kheej, tawm hauv nws lub cev ib negligible nqi ntawm cov dej. Thiab tsis txhob poob lawv, Tardigrada ntaub ntawv rau ntawm qhov chaw ntawm lub cev ib yam ntawm cov ciab plhaub. Nyob rau hauv lub qhuav daim ntawv nyob rau hauv tardigrades tshuab txais ntxiv tiv thaiv zog: ib tug qab zib molecule los mus tiv thaiv cov expansion ntawm lub hlwb pib ua antioxidants uas thaum nws tawg thiab txwv tsis pub cov puas tsuaj ntawm DNA. Nyob rau kev nkag los rau cov ib puag ncig dej lub cev tardigrades pib nqus, thiab tag nrho cov tseem ceeb heev functions raug txum tim rov.

Ntuj cov yeeb ncuab dej Xyooj

Dua li ntawm qhov kev loj hlob, dej Xyooj tsis txawj tuag. Ntse counteracting phiv lwm yam, nws yog heev tsis paub pab tiv thaiv txhom uas tsis averse mus noj lawv. Nyob rau hauv tas li ntawd mus rau lawv tus kheej cov txheeb ze, tardigrades raug rotifers tawm tsam, mites, springtails, thiab round cua nab, cov kab ntawm ntau yam kab thiab Crayfish. Part tardigrades tuag, ua prey ntawm carnivorous mushroom hyphae nws interwoven loops, nyob rau hauv uas, raws li nyob rau hauv ib cuab, dej daig Xyooj, whereupon fungal filaments loj hlob mus rau hauv nws. Nyob rau hauv tas li ntawd, muaj cov fungi, uas nws cov noob pwm yog txaus nyiam mus tardigrades nyob rau hauv cov zaub mov tswv yim. Txawm li cas los, ib zaug nyob rau hauv lub gut ntawm cov dej dais, lub noob yuav ciaj sia, siv ib tug tsiaj raws li ib tug as nruab nrab.