波塞東龍(long)(long)(long)(long)可(ke)能是已知的最高(gao)的恐(kong)龍(long)(long)(long)(long)。在美國俄克(ke)拉(la)荷馬州【oklahoma, usa】發現。波塞東龍(long)(long)(long)(long)是一(yi)種類似于(yu)腕(wan)龍(long)(long)(long)(long)的恐(kong)龍(long)(long)(long)(long),但更(geng)大(da)(da)。波塞東龍(long)(long)(long)(long)大(da)(da)約(yue)有(you)30米(mi)(mi)長,但可(ke)能高(gao)達18米(mi)(mi),比(bi)最大(da)(da)的腕(wan)龍(long)(long)(long)(long)還高(gao)4-5米(mi)(mi),體重達50-60噸。波塞東龍(long)(long)(long)(long)的脖子(zi)可(ke)能比(bi)馬門溪龍(long)(long)(long)(long)的還長,達到12米(mi)(mi)左(zuo)右。他的一(yi)截(jie)頸椎就有(you)1.5米(mi)(mi)長。
波(bo)(bo)塞(sai)東(dong)龍(long)的(de)(de)化石(shi)包含:四個(ge)天然狀(zhuang)(zhuang)態的(de)(de)頸(jing)椎(中間第(di)五到第(di)八個(ge))、以(yi)及頸(jing)部(bu)肋(lei)(lei)骨。波(bo)(bo)塞(sai)東(dong)龍(long)的(de)(de)脊(ji)椎骨非常(chang)地長(chang)(chang)(chang),最(zui)大的(de)(de)一(yi)個(ge)脊(ji)椎骨長(chang)(chang)(chang)度約1.4米,是紀錄中最(zui)長(chang)(chang)(chang)的(de)(de)。對于(yu)這些骨頭的(de)(de)檢驗(yan),顯(xian)示出它們是由(you)蜂(feng)窩狀(zhuang)(zhuang)骨細(xi)(xi)胞(bao)(bao)所構成,而且(qie)骨細(xi)(xi)胞(bao)(bao)非常(chang)細(xi)(xi),類似雞(ji)或鴕鳥(niao)的(de)(de)骨細(xi)(xi)胞(bao)(bao),使得波(bo)(bo)塞(sai)東(dong)龍(long)的(de)(de)頸(jing)部(bu)較(jiao)輕,且(qie)較(jiao)容易舉起(qi)。波(bo)(bo)塞(sai)東(dong)龍(long)的(de)(de)頸(jing)部(bu)肋(lei)(lei)骨極長(chang)(chang)(chang),第(di)六節(jie)頸(jing)肋(lei)(lei)的(de)(de)長(chang)(chang)(chang)度為3.42米,比長(chang)(chang)(chang)頸(jing)巨(ju)龍(long)的(de)(de)最(zui)長(chang)(chang)(chang)頸(jing)肋(lei)(lei)長(chang)(chang)(chang)18%,也超(chao)越馬門溪龍(long)的(de)(de)頸(jing)肋(lei)(lei)。
波塞(sai)東(dong)龍(long)的體(ti)型(xing)估(gu)計,是(shi)(shi)根據(ju)波塞(sai)東(dong)龍(long)的四個頸椎(zhui),與柏林亨(heng)波特博物館的長頸巨龍(long)標本(ben)(ben)(編號(hao)HM SII)比較(jiao)得來的數(shu)據(ju)。編號(hao)HM SII標本(ben)(ben)是(shi)(shi)已知(zhi)最完整的腕(wan)龍(long)類化(hua)(hua)石,但該標本(ben)(ben)被認為由不(bu)(bu)同個體(ti)化(hua)(hua)石拼湊(cou)而(er)成(cheng),因(yin)此數(shu)據(ju)可(ke)能不(bu)(bu)完全正確。波塞(sai)東(dong)龍(long)與其他腕(wan)龍(long)科近親的比較(jiao)是(shi)(shi)困難的,因(yin)為有限的化(hua)(hua)石紀錄。
波塞(sai)東龍的(de)的(de)頸(jing)(jing)部(bu)長(chang)(chang)度(du)被估(gu)計為11.25到12米,而編號HM SII的(de)腕龍標本(ben)頸(jing)(jing)部(bu)長(chang)(chang)度(du)為9米。這(zhe)(zhe)個(ge)數據是(shi)假(jia)設(she)波塞(sai)東龍的(de)頸(jing)(jing)部(bu)其它部(bu)分比(bi)例與(yu)長(chang)(chang)頸(jing)(jing)巨龍頸(jing)(jing)部(bu)比(bi)例是(shi)一樣(yang)的(de),這(zhe)(zhe)是(shi)個(ge)非常合理的(de)假(jia)設(she)方(fang)式。
波(bo)塞東(dong)(dong)龍可(ke)能可(ke)以將頭部(bu)高(gao)(gao)舉過(guo)地(di)面(mian)達17米(mi),大約是(shi)六(liu)層樓高(gao)(gao)。腕龍科(ke)恐龍的(de)長頸部(bu)與高(gao)(gao)肩膀,使得它們是(shi)已知最高(gao)(gao)的(de)一群恐龍。在某些層面(mian),波(bo)塞東(dong)(dong)龍的(de)體(ti)(ti)格類似(si)現(xian)代長頸鹿,它們同樣(yang)擁(yong)有(you)短身(shen)體(ti)(ti)與長頸部(bu)。相較而(er)言,長頸巨龍可(ke)將頭部(bu)高(gao)(gao)舉到離地(di)面(mian)13.5米(mi)。波(bo)塞東(dong)(dong)龍的(de)肩膀可(ke)能有(you)6或7米(mi)高(gao)(gao),而(er)身(shen)長被(bei)估計約為30米(mi)或是(shi)34米(mi)長。
波(bo)塞東(dong)(dong)龍(long)的(de)(de)體(ti)重(zhong)(zhong)被(bei)估計(ji)為50到(dao)60公(gong)噸(dun)之間。波(bo)塞東(dong)(dong)龍(long)的(de)(de)脊(ji)椎骨比長頸(jing)(jing)(jing)巨(ju)龍(long)的(de)(de)脊(ji)椎骨還(huan)長約25%到(dao)33%,但直徑(jing)僅大了(le)10%到(dao)15%。這(zhe)些數據(ju)(ju)意味者(zhe)波(bo)塞東(dong)(dong)龍(long)的(de)(de)身體(ti)可能比長頸(jing)(jing)(jing)巨(ju)龍(long)還(huan)巨(ju)大,但就比例而言(yan)(yan)頸(jing)(jing)(jing)部(bu)較小(xiao)。長頸(jing)(jing)(jing)巨(ju)龍(long)的(de)(de)體(ti)重(zhong)(zhong)為40到(dao)44公(gong)噸(dun),這(zhe)個數據(ju)(ju)是(shi)將不同測(ce)量的(de)(de)結(jie)果平(ping)均得(de)到(dao)的(de)(de)數據(ju)(ju)。然(ran)而,任何估計(ji)都是(shi)某(mou)些科(ke)學家(jia)的(de)(de)一家(jia)之言(yan)(yan),就已經發現的(de)(de)恐龍(long)木(mu)乃伊就較其骨骼判斷要大1/4來分析,基于(yu)4節頸(jing)(jing)(jing)骨的(de)(de)波(bo)塞東(dong)(dong)龍(long)的(de)(de)最大估計(ji)值為肩高8.5米,臀高6.75米,頭部(bu)可以達到(dao)18.3米高,體(ti)重(zhong)(zhong)在(zai)55噸(dun)以上或達到(dao)80噸(dun)。
然而(er),相較(jiao)于(yu)長頸巨龍(long)(long)(long),波(bo)(bo)塞東(dong)龍(long)(long)(long)擁有相對細長的頸部。如(ru)果波(bo)(bo)塞東(dong)龍(long)(long)(long)的身體(ti)(ti)也是較(jiao)為(wei)細長,那之(zhi)前(qian)所估計的數據將會過高。舉例而(er)言,體(ti)(ti)型較(jiao)粗壯的迷惑(huo)龍(long)(long)(long),體(ti)(ti)重(zhong)比(bi)身體(ti)(ti)較(jiao)長、但體(ti)(ti)型修長的梁龍(long)(long)(long)還重(zhong)。此外,波(bo)(bo)塞東(dong)龍(long)(long)(long)可能擁有氣囊系統,類(lei)似鳥類(lei),氣囊系統可減低蜥腳類(lei)恐龍(long)(long)(long)的體(ti)(ti)重(zhong)約20%以上。
波塞東龍(long)(long)可能是北(bei)美洲最(zui)后的(de)巨(ju)(ju)大(da)蜥(xi)腳(jiao)類(lei)恐龍(long)(long)。蜥(xi)腳(jiao)類(lei)恐龍(long)(long)包含(han)陸地上出(chu)現(xian)(xian)過最(zui)大(da)的(de)動物,是群分(fen)布(bu)廣(guang)泛且成功的(de)演化支(zhi)。它們首次(ci)出(chu)現(xian)(xian)于早侏羅(luo)紀(ji),并且很快地散(san)布(bu)到(dao)(dao)全世(shi)界。到(dao)(dao)了晚(wan)(wan)(wan)侏羅(luo)紀(ji),梁龍(long)(long)科與腕龍(long)(long)科恐龍(long)(long)在(zai)北(bei)美洲與非洲等地占優勢,到(dao)(dao)了晚(wan)(wan)(wan)白堊(e)紀(ji),泰坦(tan)巨(ju)(ju)龍(long)(long)科廣(guang)泛分(fen)布(bu)于南半球。在(zai)晚(wan)(wan)(wan)侏羅(luo)紀(ji)到(dao)(dao)晚(wan)(wan)(wan)白堊(e)紀(ji)期間(jian),蜥(xi)腳(jiao)類(lei)的(de)化石紀(ji)錄很稀少。這段期間(jian)的(de)北(bei)美洲很少發現(xian)(xian)標本,所發現(xian)(xian)的(de)標本也通常(chang)是破碎骨(gu)頭(tou),或是幼(you)年個體。而(er)白堊(e)紀(ji)存活的(de)蜥(xi)腳(jiao)類(lei)恐龍(long)(long)在(zai)體型(xing)上縮減(jian)(身長減(jian)到(dao)(dao)15米左右,而(er)體重為10到(dao)(dao)15公噸),因此(ci)波塞東龍(long)(long)的(de)發現(xian)(xian)相(xiang)當不尋常(chang)。
波(bo)塞東(dong)(dong)龍(long)生存(cun)于(yu)墨西(xi)哥(ge)灣(wan)的(de)(de)海岸,墨西(xi)哥(ge)灣(wan)的(de)(de)海岸在當時侵入到奧(ao)克拉(la)荷馬州一帶,形成巨大的(de)(de)三角洲,類(lei)似今日的(de)(de)密(mi)西(xi)西(xi)比河三角洲。這個(ge)(ge)地(di)區在當時可(ke)能沒有掠(lve)食動物可(ke)以攻擊(ji)完全成長的(de)(de)波(bo)塞東(dong)(dong)龍(long)個(ge)(ge)體(ti),但肉(rou)食龍(long)下目的(de)(de)高(gao)棘龍(long)(體(ti)型較小(xiao)于(yu)暴(bao)龍(long))與(yu)以群體(ti)行(xing)動的(de)(de)恐爪龍(long)可(ke)能以幼年波(bo)塞東(dong)(dong)龍(long)個(ge)(ge)體(ti)為獵物。
在2004年(nian),德恩·奈許(xu)(Darren Naish)與他的(de)(de)同事敘述了一只巨大腕(wan)龍科(ke)恐(kong)龍,該(gai)恐(kong)龍發(fa)現于早(zao)白堊(e)(e)紀(ji)(ji)的(de)(de)英格蘭,并類似于波塞東龍。該(gai)腕(wan)龍科(ke)恐(kong)龍僅(jin)發(fa)現兩個頸椎,在某些細節明(ming)顯(xian)地類似波塞東龍,而(er)它們可能在體型上相(xiang)似。該(gai)腕(wan)龍科(ke)恐(kong)龍的(de)(de)發(fa)現突(tu)顯(xian)了早(zao)白堊(e)(e)紀(ji)(ji)時(shi)期北美洲(zhou)與歐洲(zhou)恐(kong)龍的(de)(de)相(xiang)似。