短(duan)(duan)(duan)命(ming)菊(ju)(The short-lived Chrysanthemum)是世(shi)界(jie)上(shang)生(sheng)(sheng)(sheng)(sheng)命(ming)周(zhou)期最短(duan)(duan)(duan)的(de)植(zhi)(zhi)物(wu)之一(yi),它(ta)(ta)的(de)壽(shou)命(ming)還不(bu)到一(yi)個月。這(zhe)種生(sheng)(sheng)(sheng)(sheng)活(huo)習(xi)(xi)性(xing)是它(ta)(ta)適(shi)應特(te)殊(shu)(shu)生(sheng)(sheng)(sheng)(sheng)存(cun)環境的(de)結(jie)果。短(duan)(duan)(duan)命(ming)菊(ju)又叫"齒(chi)子草",是菊(ju)科植(zhi)(zhi)物(wu),生(sheng)(sheng)(sheng)(sheng)活(huo)在非洲撒哈拉(la)大沙(sha)漠(mo)中。那(nei)里長(chang)(chang)期干旱,很少降雨(yu)。許多(duo)沙(sha)漠(mo)植(zhi)(zhi)物(wu)都有(you)退(tui)化的(de)葉片、保存(cun)水分的(de)本領來適(shi)應干旱環境。短(duan)(duan)(duan)命(ming)菊(ju)卻與眾不(bu)同,它(ta)(ta)形成(cheng)了迅(xun)速生(sheng)(sheng)(sheng)(sheng)長(chang)(chang)和成(cheng)熟的(de)特(te)殊(shu)(shu)習(xi)(xi)性(xing)。只(zhi)要沙(sha)漠(mo)里稍微(wei)降了一(yi)點(dian)雨(yu),地面稍稍有(you)點(dian)濕潤,它(ta)(ta)就立刻發芽(ya),生(sheng)(sheng)(sheng)(sheng)長(chang)(chang)開(kai)花。整個一(yi)生(sheng)(sheng)(sheng)(sheng)的(de)生(sheng)(sheng)(sheng)(sheng)命(ming)周(zhou)期,只(zhi)有(you)短(duan)(duan)(duan)短(duan)(duan)(duan)的(de)三四個星期。
它的(de)(de)舌(she)狀花(hua)排列在頭狀花(hua)序周圍,像鋸齒一樣。有趣(qu)的(de)(de)是,短命(ming)(ming)菊(ju)(ju)的(de)(de)花(hua)對(dui)濕度極其敏感,空氣干燥(zao)時(shi)就(jiu)趕快閉合(he)起來;稍稍濕潤時(shi)就(jiu)迅(xun)速(su)開放(fang),快速(su)結果。果實熟了,縮成球形,隨風飄滾,傳(chuan)播他鄉,繁衍后代。由于它生命(ming)(ming)短促,來去匆匆,所(suo)以(yi)才得(de)“短命(ming)(ming)菊(ju)(ju)”之(zhi)名。