阿(a)拉(la)(la)摩(mo)(mo)(mo)(mo)龍(long)(long)(long)(Alamosaurus),又譯阿(a)拉(la)(la)莫龍(long)(long)(long),是(shi)薩爾塔龍(long)(long)(long)科下的(de)一(yi)阿(a)拉(la)(la)摩(mo)(mo)(mo)(mo)龍(long)(long)(long)阿(a)拉(la)(la)摩(mo)(mo)(mo)(mo)龍(long)(long)(long)個(ge)(ge)屬,生(sheng)活于上(shang)白堊紀的(de)北美洲(zhou)。它(ta)(ta)是(shi)一(yi)種大(da)(da)型(xing)的(de)四足的(de)植食(shi)性恐(kong)龍(long)(long)(long),而它(ta)(ta)所屬的(de)泰坦巨龍(long)(long)(long)家族,也(ye)是(shi)這個(ge)(ge)世(shi)界上(shang)存在(zai)的(de)最后的(de)植食(shi)恐(kong)龍(long)(long)(long)家族。身長超過(guo)30米,體(ti)重可達75噸(dun)。阿(a)拉(la)(la)摩(mo)(mo)(mo)(mo)龍(long)(long)(long)與其他蜥(xi)腳(jiao)下目的(de)恐(kong)龍(long)(long)(long)相(xiang)似,有(you)著長的(de)頸部及(ji)尾巴,末(mo)端有(you)著鞭索結構。阿(a)拉(la)(la)摩(mo)(mo)(mo)(mo)龍(long)(long)(long)和很(hen)多大(da)(da)型(xing)蜥(xi)腳(jiao)類植食(shi)恐(kong)龍(long)(long)(long)一(yi)樣是(shi)大(da)(da)個(ge)(ge)子(zi),它(ta)(ta)也(ye)有(you)長長的(de)脖子(zi)和尾巴。
阿(a)(a)拉(la)(la)摩(mo)龍(long)(long)(long)(long)(long)(long)明顯是泰坦巨龍(long)(long)(long)(long)(long)(long)類(lei)(lei)的(de)(de)派(pai)生成員,但是它在該科(ke)內(nei)的(de)(de)關系卻不甚清楚。一(yi)個(ge)(ge)主要(yao)的(de)(de)分析(xi)將(jiang)阿(a)(a)拉(la)(la)摩(mo)龍(long)(long)(long)(long)(long)(long)與(yu)后凹尾龍(long)(long)(long)(long)(long)(long)分類(lei)(lei)于薩(sa)爾塔(ta)龍(long)(long)(long)(long)(long)(long)科(ke)的(de)(de)后凹尾龍(long)(long)(long)(long)(long)(long)亞科(ke)。另(ling)一(yi)個(ge)(ge)主要(yao)爭論的(de)(de)分析(xi)則指阿(a)(a)拉(la)(la)摩(mo)龍(long)(long)(long)(long)(long)(long)是柏(bo)利連尼龍(long)(long)(long)(long)(long)(long)的(de)(de)姊妹分類(lei)(lei),只是它們都(dou)是被分類(lei)(lei)在薩(sa)爾塔(ta)龍(long)(long)(long)(long)(long)(long)科(ke)之外。其他科(ke)學家亦(yi)發現,在分支系統學及形(xing)態學上,阿(a)(a)拉(la)(la)摩(mo)龍(long)(long)(long)(long)(long)(long)與(yu)內(nei)烏肯龍(long)(long)(long)(long)(long)(long)及巴西的(de)(de)三角區(qu)龍(long)(long)(long)(long)(long)(long)有(you)獨特的(de)(de)相似性。
阿(a)(a)拉(la)(la)摩龍(long)是北美洲(zhou)(zhou)晚白堊世唯一(yi)的(de)(de)泰(tai)坦龍(long)類,關(guan)于(yu)它(ta)的(de)(de)起(qi)源也(ye)一(yi)直個存在(zai)爭議(yi)的(de)(de)話題。以往的(de)(de)觀點(dian)認(ren)為阿(a)(a)拉(la)(la)摩龍(long)可(ke)能從南(nan)美州或者亞洲(zhou)(zhou)的(de)(de)路橋(qiao)遷徙而來,但(dan)也(ye)有可(ke)能起(qi)源于(yu)北美洲(zhou)(zhou)本土。我(wo)們對(dui)阿(a)(a)拉(la)(la)摩龍(long)的(de)(de)研(yan)(yan)究(jiu)大多源于(yu)未發育成(cheng)熟的(de)(de)個體,近年對(dui)阿(a)(a)拉(la)(la)摩龍(long)成(cheng)年標本的(de)(de)研(yan)(yan)究(jiu)后得知,阿(a)(a)拉(la)(la)摩龍(long)其(qi)實與南(nan)美洲(zhou)(zhou)的(de)(de)隆柯(ke)龍(long)類關(guan)系更(geng)(geng)近,所以阿(a)(a)拉(la)(la)摩龍(long)更(geng)(geng)有可(ke)能是由南(nan)美洲(zhou)(zhou)遷徙至(zhi)北美州的(de)(de)。主要分布在(zai)今天的(de)(de)美國南(nan)部。
阿拉(la)(la)(la)摩(mo)龍是(shi)最后的(de)蜥腳類恐龍之(zhi)一(yi),成(cheng)(cheng)年(nian)阿拉(la)(la)(la)摩(mo)龍體長超(chao)過30米,重(zhong)達75噸。因為它們身(shen)體龐大(da),所以(yi)它們一(yi)天可吃(chi)下(xia)(xia)一(yi)噸重(zhong)的(de)樹葉(xie)。十幾只(zhi)阿拉(la)(la)(la)摩(mo)龍幾小時就(jiu)能吃(chi)光一(yi)片樹林。阿拉(la)(la)(la)摩(mo)龍每天都(dou)必(bi)須(xu)四(si)處遷徙尋(xun)找食物,因此,科學家推測雌性阿拉(la)(la)(la)摩(mo)龍從(cong)不筑(zhu)巢生蛋,而(er)是(shi)每次只(zhi)下(xia)(xia)5,6只(zhi)蛋,從(cong)而(er)提高后代的(de)存(cun)活率。通常(chang)情況下(xia)(xia),每3000枚蛋中,只(zhi)有一(yi)個(ge)可以(yi)順利(li)活到成(cheng)(cheng)年(nian)。
阿(a)(a)(a)拉摩(mo)龍(long)有許多骨骼(ge)和散(san)骨化石(shi)(shi)(shi)的(de)(de)(de)發現,意味著阿(a)(a)(a)拉摩(mo)龍(long)分(fen)布很(hen)廣(guang),是一(yi)個成(cheng)功的(de)(de)(de)物種(zhong)。頭(tou)骨化石(shi)(shi)(shi)仍沒(mei)有發現。保存最完整的(de)(de)(de)化石(shi)(shi)(shi)來自于亞(ya)成(cheng)年的(de)(de)(de)阿(a)(a)(a)拉摩(mo)龍(long),通(tong)過這(zhe)些化石(shi)(shi)(shi)可以推算(suan)出(chu)成(cheng)年阿(a)(a)(a)拉摩(mo)龍(long)的(de)(de)(de)大(da)小。這(zhe)些龐大(da)的(de)(de)(de)植食(shi)(shi)恐龍(long)可能是以群(qun)體生(sheng)活,以高大(da)樹(shu)木上的(de)(de)(de)葉子為食(shi)(shi),然后用胃里(li)的(de)(de)(de)胃石(shi)(shi)(shi)幫助消化。它們(men)和掠食(shi)(shi)性(xing)的(de)(de)(de)暴龍(long)類恐龍(long)及其他獸腳類恐龍(long)生(sheng)活在同(tong)一(yi)片土地上很(hen)可能是最后滅亡的(de)(de)(de)非鳥類恐龍(long)之一(yi)。
成年阿(a)拉(la)(la)摩龍體型巨大,沒(mei)有天敵,但霸王(wang)龍會攻(gong)擊(ji)小(xiao)個體阿(a)拉(la)(la)摩龍,一(yi)塊小(xiao)個體的阿(a)拉(la)(la)摩龍頸骨化(hua)石,因為上面還保存(cun)有霸王(wang)龍的牙齒(chi)化(hua)石,而在另一(yi)具小(xiao)個體阿(a)拉(la)(la)摩龍的前肢化(hua)石上也發(fa)現過霸王(wang)龍的咬(yao)痕。可以想(xiang)象當(dang)時霸王(wang)龍襲擊(ji)阿(a)拉(la)(la)摩龍時的場景。