阿拉(la)(la)摩龍(long)(Alamosaurus),又譯阿拉(la)(la)莫龍(long),是(shi)(shi)(shi)薩爾塔(ta)龍(long)科下(xia)的(de)(de)(de)一(yi)(yi)阿拉(la)(la)摩龍(long)阿拉(la)(la)摩龍(long)個屬,生活于上白堊紀(ji)的(de)(de)(de)北美洲(zhou)。它是(shi)(shi)(shi)一(yi)(yi)種大型的(de)(de)(de)四足的(de)(de)(de)植食(shi)性(xing)恐(kong)(kong)(kong)龍(long),而它所屬的(de)(de)(de)泰坦巨龍(long)家(jia)(jia)族(zu),也(ye)是(shi)(shi)(shi)這個世界上存在的(de)(de)(de)最后的(de)(de)(de)植食(shi)恐(kong)(kong)(kong)龍(long)家(jia)(jia)族(zu)。身長(chang)(chang)超過30米,體重(zhong)可達75噸。阿拉(la)(la)摩龍(long)與(yu)其他(ta)蜥腳下(xia)目(mu)的(de)(de)(de)恐(kong)(kong)(kong)龍(long)相似,有著(zhu)長(chang)(chang)的(de)(de)(de)頸部及尾(wei)巴,末端有著(zhu)鞭索結構。阿拉(la)(la)摩龍(long)和很多大型蜥腳類植食(shi)恐(kong)(kong)(kong)龍(long)一(yi)(yi)樣是(shi)(shi)(shi)大個子,它也(ye)有長(chang)(chang)長(chang)(chang)的(de)(de)(de)脖子和尾(wei)巴。
阿(a)(a)拉(la)(la)摩龍(long)(long)(long)(long)(long)明顯(xian)是(shi)(shi)(shi)泰(tai)坦(tan)巨(ju)龍(long)(long)(long)(long)(long)類(lei)的派生成員,但是(shi)(shi)(shi)它(ta)在該科(ke)內(nei)的關系卻不甚(shen)清楚。一個主要的分(fen)析將阿(a)(a)拉(la)(la)摩龍(long)(long)(long)(long)(long)與后(hou)凹尾龍(long)(long)(long)(long)(long)分(fen)類(lei)于薩(sa)爾塔(ta)龍(long)(long)(long)(long)(long)科(ke)的后(hou)凹尾龍(long)(long)(long)(long)(long)亞科(ke)。另一個主要爭論(lun)的分(fen)析則指阿(a)(a)拉(la)(la)摩龍(long)(long)(long)(long)(long)是(shi)(shi)(shi)柏利連尼龍(long)(long)(long)(long)(long)的姊妹分(fen)類(lei),只(zhi)是(shi)(shi)(shi)它(ta)們(men)都是(shi)(shi)(shi)被分(fen)類(lei)在薩(sa)爾塔(ta)龍(long)(long)(long)(long)(long)科(ke)之外。其他科(ke)學家(jia)亦發現,在分(fen)支系統學及形態(tai)學上,阿(a)(a)拉(la)(la)摩龍(long)(long)(long)(long)(long)與內(nei)烏肯龍(long)(long)(long)(long)(long)及巴西的三角(jiao)區(qu)龍(long)(long)(long)(long)(long)有獨特(te)的相似性。
阿(a)拉(la)(la)摩(mo)龍是北美(mei)洲(zhou)晚(wan)白堊(e)世唯(wei)一(yi)的(de)(de)泰坦龍類(lei),關于(yu)它的(de)(de)起源(yuan)(yuan)也一(yi)直個(ge)存在爭議的(de)(de)話題(ti)。以往的(de)(de)觀點認(ren)為阿(a)拉(la)(la)摩(mo)龍可能從南(nan)美(mei)州或(huo)者亞洲(zhou)的(de)(de)路橋遷徙(xi)而(er)來,但也有可能起源(yuan)(yuan)于(yu)北美(mei)洲(zhou)本土。我(wo)們對(dui)阿(a)拉(la)(la)摩(mo)龍的(de)(de)研(yan)究大多源(yuan)(yuan)于(yu)未(wei)發育成(cheng)熟的(de)(de)個(ge)體,近(jin)年對(dui)阿(a)拉(la)(la)摩(mo)龍成(cheng)年標(biao)本的(de)(de)研(yan)究后得知(zhi),阿(a)拉(la)(la)摩(mo)龍其實(shi)與南(nan)美(mei)洲(zhou)的(de)(de)隆柯(ke)龍類(lei)關系更近(jin),所以阿(a)拉(la)(la)摩(mo)龍更有可能是由南(nan)美(mei)洲(zhou)遷徙(xi)至(zhi)北美(mei)州的(de)(de)。主要分布在今天的(de)(de)美(mei)國南(nan)部(bu)。
阿(a)(a)(a)拉(la)(la)摩龍(long)是(shi)最后的(de)蜥腳類恐龍(long)之一(yi),成年(nian)阿(a)(a)(a)拉(la)(la)摩龍(long)體長超過(guo)30米,重(zhong)達75噸。因為它們(men)身(shen)體龐大,所以它們(men)一(yi)天可(ke)吃下一(yi)噸重(zhong)的(de)樹(shu)葉。十幾(ji)只阿(a)(a)(a)拉(la)(la)摩龍(long)幾(ji)小時就能吃光(guang)一(yi)片(pian)樹(shu)林。阿(a)(a)(a)拉(la)(la)摩龍(long)每(mei)天都必須(xu)四處遷(qian)徙(xi)尋找(zhao)食(shi)物(wu),因此,科學家(jia)推測雌性阿(a)(a)(a)拉(la)(la)摩龍(long)從不(bu)筑巢(chao)生蛋,而(er)是(shi)每(mei)次(ci)只下5,6只蛋,從而(er)提高后代的(de)存活(huo)率。通常情況下,每(mei)3000枚蛋中(zhong),只有一(yi)個可(ke)以順利活(huo)到成年(nian)。
阿拉(la)摩(mo)龍(long)(long)(long)有(you)許(xu)多骨骼(ge)和散骨化石(shi)的(de)發現,意味著阿拉(la)摩(mo)龍(long)(long)(long)分(fen)布很(hen)廣,是一(yi)(yi)個成功的(de)物種。頭骨化石(shi)仍沒有(you)發現。保(bao)存最(zui)完整的(de)化石(shi)來自于亞成年的(de)阿拉(la)摩(mo)龍(long)(long)(long),通過這些(xie)化石(shi)可以推算出(chu)成年阿拉(la)摩(mo)龍(long)(long)(long)的(de)大(da)小。這些(xie)龐大(da)的(de)植(zhi)食(shi)(shi)恐龍(long)(long)(long)可能是以群體生活(huo),以高大(da)樹木上的(de)葉子為食(shi)(shi),然后用胃里的(de)胃石(shi)幫助消(xiao)化。它們和掠(lve)食(shi)(shi)性的(de)暴(bao)龍(long)(long)(long)類恐龍(long)(long)(long)及其他獸腳類恐龍(long)(long)(long)生活(huo)在同一(yi)(yi)片土(tu)地(di)上很(hen)可能是最(zui)后滅亡(wang)的(de)非(fei)鳥(niao)類恐龍(long)(long)(long)之一(yi)(yi)。
成年(nian)阿拉摩龍體型巨大,沒有天(tian)敵,但霸王(wang)龍會攻擊小(xiao)(xiao)個體阿拉摩龍,一(yi)塊小(xiao)(xiao)個體的(de)(de)(de)(de)阿拉摩龍頸骨化(hua)(hua)石,因為上面還保(bao)存有霸王(wang)龍的(de)(de)(de)(de)牙齒化(hua)(hua)石,而(er)在另(ling)一(yi)具小(xiao)(xiao)個體阿拉摩龍的(de)(de)(de)(de)前肢化(hua)(hua)石上也發現過霸王(wang)龍的(de)(de)(de)(de)咬痕。可以想象當時霸王(wang)龍襲(xi)擊阿拉摩龍時的(de)(de)(de)(de)場景。