異(yi)特(te)(te)龍(long)(long)(long),又名躍龍(long)(long)(long)或異(yi)龍(long)(long)(long),是(shi)蜥臀目(mu)獸腳(jiao)亞(ya)目(mu)肉食龍(long)(long)(long)下(xia)目(mu)恐龍(long)(long)(long)的一屬。異(yi)特(te)(te)龍(long)(long)(long)是(shi)種(zhong)(zhong)中(zhong)型的二足、掠(lve)食性恐龍(long)(long)(long),身長8.5米,最大(da)9.7米,體(ti)重1.5~3噸(dun)最重3.6噸(dun)。它們生存于晚(wan)侏羅紀,約(yue)1億5500萬年(nian)(nian)前(qian)到(dao)1億3500萬年(nian)(nian)前(qian)。自(zi)從在1877年(nian)(nian)被奧塞內爾·查(cha)利斯·馬什(Othniel Charles Marsh)命名以來(lai),已有許多的可能種(zhong)(zhong)被歸類(lei)于異(yi)特(te)(te)龍(long)(long)(long)屬,但只有少數被認為是(shi)有效種(zhong)(zhong)。
異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)屬(shu)于(yu)(yu)(yu)異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke),異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)是(shi)(shi)一個大型(xing)獸(shou)腳(jiao)亞目的(de)(de)(de)演化支。奧塞內(nei)爾(er)(er)·查利(li)斯·馬什在(zai)(zai)1878年建立異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke);但(dan)在(zai)(zai)70年代(dai)以(yi)(yi)前(qian),異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)很少(shao)被(bei)(bei)使用(yong),取而代(dai)之的(de)(de)(de)是(shi)(shi)斑龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke),但(dan)斑龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)長期以(yi)(yi)來(lai)被(bei)(bei)當作大型(xing)獸(shou)腳(jiao)類(lei)(lei)(lei)(lei)恐(kong)龍(long)(long)(long)(long)(long)的(de)(de)(de)"未歸類(lei)(lei)(lei)(lei)物(wu)種(zhong)集中(zhong)地(di)"。在(zai)(zai)1976年麥(mai)迪遜公布(bu)(bu)他(ta)的(de)(de)(de)專題(ti)論(lun)文以(yi)(yi)前(qian),跟異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)相同時期被(bei)(bei)命名的(de)(de)(de)腔軀龍(long)(long)(long)(long)(long),常(chang)被(bei)(bei)當作異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)(de)(de)同義(yi)詞,而且更常(chang)被(bei)(bei)使用(yong)。數個研(yan)(yan)究人(ren)員曾在(zai)(zai)他(ta)們的(de)(de)(de)著(zhu)作中(zhong)使用(yong)斑龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)來(lai)取代(dai)異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke),包(bao)含(han):吉爾(er)(er)摩爾(er)(er)、休尼(ni)博士、羅(luo)默博士、羅(luo)德尼(ni)·史(shi)提爾(er)(er)、以(yi)(yi)及亞歷克·沃克。在(zai)(zai)麥(mai)迪遜公布(bu)(bu)他(ta)的(de)(de)(de)具影(ying)響(xiang)力專題(ti)論(lun)文之后,異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)開始(shi)普遍使用(yong),但(dan)沒有(you)被(bei)(bei)明確的(de)(de)(de)定義(yi)。一些半科(ke)(ke)(ke)(ke)學性質的(de)(de)(de)著(zhu)作將異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)使用(yong)于(yu)(yu)(yu)不同的(de)(de)(de)大型(xing)獸(shou)腳(jiao)類(lei)(lei)(lei)(lei)恐(kong)龍(long)(long)(long)(long)(long),通常(chang)包(bao)含(han)那(nei)些比斑龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)更大型(xing)、更著(zhu)名的(de)(de)(de)物(wu)種(zhong)。在(zai)(zai)獸(shou)腳(jiao)亞目中(zhong),常(chang)被(bei)(bei)認(ren)為是(shi)(shi)異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)近親(qin)的(de)(de)(de)物(wu)種(zhong),包(bao)含(han):印度龍(long)(long)(long)(long)(long)、皮亞尼(ni)茲基(ji)龍(long)(long)(long)(long)(long)、皮爾(er)(er)逖龍(long)(long)(long)(long)(long)、永川(chuan)龍(long)(long)(long)(long)(long)、高棘龍(long)(long)(long)(long)(long)、吉蘭泰龍(long)(long)(long)(long)(long)、巧鱷(e)龍(long)(long)(long)(long)(long)、史(shi)托龍(long)(long)(long)(long)(long)、以(yi)(yi)及四川(chuan)龍(long)(long)(long)(long)(long)。隨者(zhe)相關恐(kong)龍(long)(long)(long)(long)(long)的(de)(de)(de)研(yan)(yan)究增加(jia),獸(shou)腳(jiao)類(lei)(lei)(lei)(lei)恐(kong)龍(long)(long)(long)(long)(long)開始(shi)變(bian)得多樣性。而親(qin)緣分(fen)支分(fen)類(lei)(lei)(lei)(lei)法研(yan)(yan)究則顯示,上述原本被(bei)(bei)認(ren)為是(shi)(shi)異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)近親(qin)的(de)(de)(de)物(wu)種(zhong),都(dou)不是(shi)(shi)異(yi)(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)科(ke)(ke)(ke)(ke)的(de)(de)(de)成員,只有(you)少(shao)數屬(shu)被(bei)(bei)歸類(lei)(lei)(lei)(lei)于(yu)(yu)(yu)相近的(de)(de)(de)科(ke)(ke)(ke)(ke),例如:高棘龍(long)(long)(long)(long)(long)、永川(chuan)龍(long)(long)(long)(long)(long)。
異(yi)(yi)特(te)(te)龍(long)(long)(long)(long)科(ke)是肉食(shi)(shi)龍(long)(long)(long)(long)下目的(de)(de)(de)三個(ge)科(ke)之一(yi),其(qi)他兩個(ge)分(fen)別為(wei)(wei)鯊齒龍(long)(long)(long)(long)科(ke)與中華(hua)盜(dao)龍(long)(long)(long)(long)科(ke)。在1988年,葛瑞格利·保羅提出異(yi)(yi)特(te)(te)龍(long)(long)(long)(long)科(ke)演化(hua)為(wei)(wei)暴(bao)(bao)龍(long)(long)(long)(long)科(ke),因(yin)此成(cheng)為(wei)(wei)并系群;但(dan)這個(ge)看法已(yi)遭到否定(ding),暴(bao)(bao)龍(long)(long)(long)(long)科(ke)已(yi)經被歸類為(wei)(wei)另一(yi)群獸腳類支(zhi)系,虛骨(gu)龍(long)(long)(long)(long)類。異(yi)(yi)特(te)(te)龍(long)(long)(long)(long)科(ke)是肉食(shi)(shi)龍(long)(long)(long)(long)下目中成(cheng)員最(zui)少的(de)(de)(de)一(yi)科(ke),在大多數的(de)(de)(de)研究中,除了異(yi)(yi)特(te)(te)龍(long)(long)(long)(long)屬(shu)以(yi)外(wai),只(zhi)有(you)食(shi)(shi)蜥王(wang)龍(long)(long)(long)(long)以(yi)及一(yi)個(ge)發現于法國的(de)(de)(de)未(wei)命(ming)名異(yi)(yi)特(te)(te)龍(long)(long)(long)(long)超科(ke)恐(kong)龍(long)(long)(long)(long)被認為(wei)(wei)是可(ke)能(neng)的(de)(de)(de)有(you)效(xiao)屬(shu)。Epanterias是另一(yi)個(ge)可(ke)能(neng)的(de)(de)(de)有(you)效(xiao)屬(shu),但(dan)Epanterias與食(shi)(shi)蜥王(wang)龍(long)(long)(long)(long)有(you)可(ke)能(neng)是異(yi)(yi)特(te)(te)龍(long)(long)(long)(long)屬(shu)的(de)(de)(de)大型(xing)個(ge)體(ti)。最(zui)近(jin)的(de)(de)(de)研究則保留了食(shi)(shi)蜥王(wang)龍(long)(long)(long)(long),而將Epanterias歸類于異(yi)(yi)特(te)(te)龍(long)(long)(long)(long)的(de)(de)(de)一(yi)個(ge)種。
尚不(bu)清楚(chu)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)屬究(jiu)竟有(you)(you)(you)多(duo)少(shao)個(ge)(ge)種(zhong)(zhong)(zhong)(zhong)類(lei)。自從1988年(nian)以來(lai)(lai),已有(you)(you)(you)七個(ge)(ge)種(zhong)(zhong)(zhong)(zhong)被(bei)視為(wei)是(shi)(shi)可(ke)(ke)能(neng)的(de)(de)有(you)(you)(you)效種(zhong)(zhong)(zhong)(zhong)。例如:模式(shi)(shi)種(zhong)(zhong)(zhong)(zhong)脆(cui)(cui)(cui)弱(ruo)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)(A. fragilis)、合(he)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)(A. amplexus)、歐(ou)(ou)洲(zhou)(zhou)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)(A. europaeus)、尚未有(you)(you)(you)正(zheng)式(shi)(shi)敘述(shu)的(de)(de)詹(zhan)(zhan)(zhan)氏(shi)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)(A. jimmadseni)、坦(tan)達(da)(da)格(ge)魯(lu)(lu)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)(A. tendagurensis),但(dan)其中(zhong)只(zhi)有(you)(you)(you)少(shao)數種(zhong)(zhong)(zhong)(zhong)普遍(bian)被(bei)視為(wei)有(you)(you)(you)效的(de)(de)種(zhong)(zhong)(zhong)(zhong)。此(ci)外,還有(you)(you)(you)至(zhi)少(shao)10個(ge)(ge)可(ke)(ke)疑名(ming)稱(cheng)或未敘述(shu)的(de)(de)種(zhong)(zhong)(zhong)(zhong)曾(ceng)被(bei)歸類(lei)于(yu)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)屬。在(zai)基礎堅(jian)尾(wei)龍(long)(long)(long)(long)(long)(long)(long)(long)類(lei)獸(shou)腳類(lei)恐龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)研究(jiu)中(zhong),只(zhi)有(you)(you)(you)脆(cui)(cui)(cui)弱(ruo)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)、詹(zhan)(zhan)(zhan)氏(shi)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)(被(bei)列為(wei)未命名(ming)種(zhong)(zhong)(zhong)(zhong))、以及坦(tan)達(da)(da)格(ge)魯(lu)(lu)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)被(bei)承認(ren)(ren)是(shi)(shi)可(ke)(ke)能(neng)的(de)(de)有(you)(you)(you)效種(zhong)(zhong)(zhong)(zhong);而合(he)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)(即為(wei)Epanterias)、殘暴異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)被(bei)視為(wei)是(shi)(shi)脆(cui)(cui)(cui)弱(ruo)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)異(yi)(yi)(yi)(yi)(yi)(yi)名(ming),歐(ou)(ou)洲(zhou)(zhou)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)并沒被(bei)承認(ren)(ren),巨異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)曾(ceng)被(bei)建立為(wei)食蜥王龍(long)(long)(long)(long)(long)(long)(long)(long)。合(he)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)、脆(cui)(cui)(cui)弱(ruo)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)、詹(zhan)(zhan)(zhan)氏(shi)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)、巨異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)化(hua)石都來(lai)(lai)自于(yu)莫(mo)(mo)里(li)(li)(li)(li)遜組(zu),莫(mo)(mo)里(li)(li)(li)(li)遜組(zu)散布于(yu)美國的(de)(de)科羅(luo)拉多(duo)州(zhou)(zhou)、蒙大拿州(zhou)(zhou)、新墨西(xi)哥(ge)州(zhou)(zhou)、奧克拉荷馬州(zhou)(zhou)、南達(da)(da)科他州(zhou)(zhou)、猶他州(zhou)(zhou)、以及懷俄明州(zhou)(zhou),年(nian)代(dai)為(wei)上侏羅(luo)紀的(de)(de)啟(qi)(qi)莫(mo)(mo)里(li)(li)(li)(li)階(jie)(jie)(jie)到(dao)提(ti)通階(jie)(jie)(jie)。在(zai)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)中(zhong),詹(zhan)(zhan)(zhan)氏(shi)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)化(hua)石標本最(zui)大。脆(cui)(cui)(cui)弱(ruo)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)是(shi)(shi)該地層最(zui)常發(fa)(fa)現、最(zui)著名(ming)的(de)(de)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)化(hua)石,已發(fa)(fa)現至(zhi)少(shao)60個(ge)(ge)個(ge)(ge)體(ti)的(de)(de)化(hua)石。自從80年(nian)代(dai)以來(lai)(lai),有(you)(you)(you)爭論懷疑莫(mo)(mo)里(li)(li)(li)(li)遜組(zu)是(shi)(shi)否存在(zai)者另一種(zhong)(zhong)(zhong)(zhong)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long),殘暴異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long):研究(jiu)仍(reng)維持莫(mo)(mo)里(li)(li)(li)(li)遜組(zu)只(zhi)有(you)(you)(you)脆(cui)(cui)(cui)弱(ruo)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)看法,而該地層所發(fa)(fa)現的(de)(de)不(bu)同異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)化(hua)石間(jian)的(de)(de)差異(yi)(yi)(yi)(yi)(yi)(yi),被(bei)認(ren)(ren)為(wei)是(shi)(shi)不(bu)同個(ge)(ge)體(ti)間(jian)的(de)(de)變化(hua)。歐(ou)(ou)洲(zhou)(zhou)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)化(hua)石發(fa)(fa)現于(yu)葡萄(tao)牙勞爾哈組(zu)的(de)(de)波(bo)多(duo)諾伏,體(ti)長(chang)只(zhi)有(you)(you)(you)9米2噸(dun),年(nian)代(dai)為(wei)啟(qi)(qi)莫(mo)(mo)里(li)(li)(li)(li)階(jie)(jie)(jie),可(ke)(ke)能(neng)與脆(cui)(cui)(cui)弱(ruo)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)是(shi)(shi)同一種(zhong)(zhong)(zhong)(zhong)動物。坦(tan)達(da)(da)格(ge)魯(lu)(lu)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)被(bei)發(fa)(fa)現于(yu)坦(tan)尚尼(ni)亞(ya)姆特(te)(te)(te)(te)(te)(te)(te)(te)瓦拉區的(de)(de)坦(tan)達(da)(da)格(ge)魯(lu)(lu),年(nian)代(dai)也為(wei)啟(qi)(qi)莫(mo)(mo)里(li)(li)(li)(li)階(jie)(jie)(jie)。大部分的(de)(de)研究(jiu)把坦(tan)達(da)(da)格(ge)魯(lu)(lu)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)視為(wei)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)有(you)(you)(you)效種(zhong)(zhong)(zhong)(zhong),但(dan)它有(you)(you)(you)可(ke)(ke)能(neng)是(shi)(shi)一種(zhong)(zhong)(zhong)(zhong)基礎堅(jian)尾(wei)龍(long)(long)(long)(long)(long)(long)(long)(long)類(lei),或僅是(shi)(shi)獸(shou)腳亞(ya)目的(de)(de)一個(ge)(ge)疑名(ming)。雖然歸類(lei)仍(reng)不(bu)確定(ding),坦(tan)達(da)(da)格(ge)魯(lu)(lu)異(yi)(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)(te)(te)(te)(te)(te)龍(long)(long)(long)(long)(long)(long)(long)(long)是(shi)(shi)種(zhong)(zhong)(zhong)(zhong)大型獸(shou)腳類(lei)恐龍(long)(long)(long)(long)(long)(long)(long)(long),身(shen)長(chang)可(ke)(ke)能(neng)約(yue)9公尺,體(ti)重(zhong)約(yue)有(you)(you)(you)2.5公噸(dun)。
異(yi)特龍(long)的(de)(de)可能異(yi)名(ming)有(you)腔軀龍(long)、Creosaurus、Epanterias、以及Labrosaurus。而異(yi)特龍(long)大部(bu)分(fen)的(de)(de)種是根據零碎(sui)的(de)(de)化(hua)(hua)石來(lai)命名(ming),許多被認(ren)(ren)為(wei)(wei)是破碎(sui)異(yi)特龍(long)的(de)(de)異(yi)名(ming),或者是被錯誤歸類到異(yi)特龍(long)屬(shu)。其(qi)中一個(ge)例子是Labrosaurus ferox,是由馬什在(zai)1884年所命名(ming),但他是根據一個(ge)外形(xing)奇怪的(de)(de)部(bu)分(fen)下顎,而顎部(bu)前(qian)端的(de)(de)齒(chi)列有(you)個(ge)明顯的(de)(de)缺口(kou),顎部(bu)后(hou)段(duan)則延(yan)展并外翻(fan)。后(hou)來(lai)的(de)(de)研究人員提出(chu)這個(ge)下顎骨頭具有(you)病狀(zhuang),應該是該動(dong)物生前(qian)受傷的(de)(de)痕跡,而后(hou)段(duan)變形(xing)的(de)(de)部(bu)分(fen)原因(yin)為(wei)(wei)石膏重(zhong)建的(de)(de)后(hou)果。這個(ge)化(hua)(hua)石現被認(ren)(ren)為(wei)(wei)屬(shu)于脆弱異(yi)特龍(long)。被認(ren)(ren)為(wei)(wei)屬(shu)于異(yi)特龍(long)的(de)(de)化(hua)(hua)石散布(bu)于全世界(jie),包含澳(ao)洲、西(xi)伯利(li)亞、以及瑞士,但這些化(hua)(hua)石被認(ren)(ren)為(wei)(wei)其(qi)他的(de)(de)恐(kong)龍(long)。
異特(te)龍(long)是該(gai)時期北美洲(zhou)莫里遜組(zu)最常見(jian)的大(da)型(xing)掠食者,并位在食物(wu)(wu)鏈(lian)的頂層。它(ta)們可能(neng)以其他(ta)大(da)型(xing)草(cao)食性恐(kong)龍(long)為(wei)食,例如:鳥腳目、蜥(xi)腳下目恐(kong)龍(long)。異特(te)龍(long)經常被認為(wei)采(cai)用群體(ti)合作方式攻(gong)擊(ji)(ji)蜥(xi)腳類恐(kong)龍(long),但很少(shao)證據顯示(shi)異特(te)龍(long)具(ju)有共同攻(gong)擊(ji)(ji)的社(she)會行為(wei)。它(ta)們可能(neng)采(cai)取伏擊(ji)(ji)方式攻(gong)擊(ji)(ji)大(da)型(xing)獵物(wu)(wu),使用上顎來(lai)撞擊(ji)(ji)獵物(wu)(wu)。
異(yi)特龍(long)(Allosaurus)又稱躍龍(long)或(huo)異(yi)龍(long),是蜥臀目(mu)獸腳亞目(mu)恐龍(long)的(de)一屬。異(yi)特龍(long)是種中(zhong)型(xing)的(de)二(er)足、掠(lve)食性恐龍(long),身長(chang)為9米(mi)(mi),最大可達9.7米(mi)(mi)。它(ta)們(men)生存于晚(wan)侏羅(luo)紀,約1億5500萬年~1億3500萬年前(qian)。
這是一種(zhong)大家熟(shu)知的(de)恐龍。它(ta)已經成為定(ding)義侏羅紀的(de)食肉者,以(yi)及食肉恐龍--大型獸腳類恐龍的(de)典范。
異特龍(long)具有(you)大型(xing)的頭(tou)(tou)顱骨(gu),上有(you)大型(xing)洞孔,可(ke)(ke)減輕重(zhong)量,眼睛(jing)上方擁有(you)角冠。它(ta)們的頭(tou)(tou)顱骨(gu)是由幾個分開(kai)的骨(gu)頭(tou)(tou)組成的,骨(gu)頭(tou)(tou)之間有(you)可(ke)(ke)活(huo)動關節,進食時(shi)頜部可(ke)(ke)先(xian)下(xia)上張開(kai),然后(hou)在左右撐開(kai)吞(tun)下(xia)食物;它(ta)們的下(xia)頜也可(ke)(ke)以前后(hou)滑動。嘴部擁有(you)70顆大型(xing)、銳(rui)利(li)、彎(wan)曲(qu)的牙齒。相較于大型(xing)、強壯的后(hou)肢,它(ta)們的前肢小,手部有(you)三(san)指,指爪(zhua)大而彎(wan)曲(qu),長度為25厘米。尾巴長而重(zhong),可(ke)(ke)平衡身體與頭(tou)(tou)部。異特龍(long)的骨(gu)架和其它(ta)獸(shou)腳亞目(mu)恐龍(long)一(yi)般,呈現出類似(si)鳥類的輕巧(qiao)中空特征(zheng)。
異(yi)特龍(long)是該時期北美洲莫里遜組最常見的大(da)型(xing)掠食動(dong)物,并位在食物鏈的頂層。它(ta)們(men)可能以(yi)其他大(da)型(xing)草食性恐(kong)(kong)龍(long)為食,例如:鳥(niao)腳(jiao)下(xia)目(mu)、劍龍(long)科、蜥腳(jiao)下(xia)目(mu)恐(kong)(kong)龍(long)。異(yi)特龍(long)常被認為采用群體合作方式攻擊蜥腳(jiao)類恐(kong)(kong)龍(long),但(dan)很少有證據顯示異(yi)特龍(long)具有共同(tong)攻擊的社會行為。它(ta)們(men)有可能采取伏擊方式攻擊大(da)型(xing)獵物,使(shi)用上頜來撞擊獵物。
第一(yi)個可明(ming)確歸(gui)類于異(yi)特(te)(te)龍(long)(long)(long)的化石,是在1877年由奧塞內爾·查利斯·馬什(Othniel Charles Marsh)所發現。異(yi)特(te)(te)龍(long)(long)(long)具有復雜的分類歷(li)史,過(guo)去曾有許多種最(zui)初被(bei)歸(gui)類于異(yi)特(te)(te)龍(long)(long)(long),腔軀龍(long)(long)(long),直到在克利夫蘭勞埃德采(cai)石場(chang)發現大量(liang)的化石后,異(yi)特(te)(te)龍(long)(long)(long)才成(cheng)為常用的名稱,并成(cheng)為最(zui)廣受(shou)研(yan)究的恐龍(long)(long)(long)之(zhi)一(yi)。
異(yi)(yi)特(te)龍(long)的(de)化石(shi)(shi)主要(yao)來(lai)自于北美洲的(de)莫里遜組,另外在葡萄牙、坦(tan)桑尼亞(ya)(ya)也發(fa)(fa)現了(le)(le)可(ke)能的(de)化石(shi)(shi)。異(yi)(yi)特(te)龍(long)的(de)化石(shi)(shi)是美國猶(you)他州(zhou)的(de)州(zhou)化石(shi)(shi)。由于異(yi)(yi)特(te)龍(long)是最(zui)早被(bei)發(fa)(fa)現的(de)獸腳(jiao)亞(ya)(ya)目(mu)(mu)恐龍(long)之一(yi),所以(yi)長期以(yi)來(lai)吸引了(le)(le)一(yi)般大眾的(de)注意,并出現在數個(ge)電影(ying)與電視節目(mu)(mu)中。
異特龍是種典型的大型獸腳類恐龍,擁有大型頭顱骨、粗壯的頸部、長尾巴、以及縮短的前肢。脆弱異特龍是最著名的種,平均身長為9米,而最大型的異特龍標本(編號AMNH 680)的身長估計為9·7米,體重為3.6噸。在1976年(nian)(nian),詹姆斯·麥迪(di)遜(James Madsen)的(de)(de)(de)異特(te)(te)龍(long)專題(ti)論文中,他提出異特(te)(te)龍(long)的(de)(de)(de)身長最(zui)大值(zhi)為13米。如同其他的(de)(de)(de)恐龍(long),異特(te)(te)龍(long)的(de)(de)(de)體(ti)重估(gu)計(ji)值(zhi)也有爭議,自(zi)20世紀80年(nian)(nian)代(dai)以(yi)來,成(cheng)年(nian)(nian)異特(te)(te)龍(long)的(de)(de)(de)體(ti)重估(gu)計(ji)值(zhi),已有1000公斤(jin),以(yi)及(ji)1010公斤(jin)等不同的(de)(de)(de)數據。
莫里遜組(zu)專家(jia)約(yue)翰·福斯(si)特(te)(te)(John Foster)提出,大型的(de)(de)(de)成(cheng)年脆弱異(yi)(yi)(yi)特(te)(te)龍的(de)(de)(de)體重為(wei)1000公(gong)斤,但根據他所測量、參考的(de)(de)(de)股骨(gu),合(he)理的(de)(de)(de)估(gu)計(ji)值應約(yue)750~800公(gong)斤。有數個(ge)(ge)巨型標(biao)本(ben)被歸(gui)類于(yu)異(yi)(yi)(yi)特(te)(te)龍屬(shu),但可能事實上屬(shu)于(yu)其(qi)他恐(kong)龍。異(yi)(yi)(yi)特(te)(te)龍的(de)(de)(de)近(jin)親(qin)食(shi)蜥(xi)王龍(編號OMNH 1708)身長(chang)可能有13米。曾被歸(gui)類于(yu)異(yi)(yi)(yi)特(te)(te)龍的(de)(de)(de)一種,巨異(yi)(yi)(yi)特(te)(te)龍(A. maximus),最近(jin)的(de)(de)(de)研究多認為(wei)它(ta)們是(shi)個(ge)(ge)別的(de)(de)(de)屬(shu)。另一個(ge)(ge)可能屬(shu)于(yu)異(yi)(yi)(yi)特(te)(te)龍的(de)(de)(de)標(biao)本(ben)(編號AMNH 5768),曾長(chang)期(qi)被歸(gui)類于(yu)Epanterias,身長(chang)為(wei)12.1公(gong)尺。在新(xin)墨西哥州莫里遜組(zu)的(de)(de)(de)彼得森采石場,發(fa)現一個(ge)(ge)大型的(de)(de)(de)異(yi)(yi)(yi)特(te)(te)龍科部(bu)分骨(gu)骼,是(shi)食(shi)蜥(xi)王龍的(de)(de)(de)第二個(ge)(ge)標(biao)本(ben)。
在獸腳(jiao)亞目之中(zhong),異(yi)特(te)龍(long)的(de)(de)(de)頭(tou)顱骨(gu)、牙(ya)(ya)齒(chi)(chi)(chi)與身(shen)體(ti)的(de)(de)(de)比例(li)適中(zhong)。葛瑞格利·保羅(Gregory S. Paul)依據一(yi)個長(chang)(chang)度為(wei)84.5公分的(de)(de)(de)異(yi)特(te)龍(long)頭(tou)顱骨(gu),估計(ji)該(gai)個體(ti)的(de)(de)(de)身(shen)長(chang)(chang)為(wei)7.9米。每(mei)(mei)塊(kuai)前上顎(e)骨(gu)各(ge)有(you)5顆(ke)(ke)牙(ya)(ya)齒(chi)(chi)(chi),牙(ya)(ya)齒(chi)(chi)(chi)的(de)(de)(de)橫剖面呈D形,而每(mei)(mei)塊(kuai)上顎(e)骨(gu)約(yue)有(you)14到(dao)17顆(ke)(ke)牙(ya)(ya)齒(chi)(chi)(chi);異(yi)特(te)龍(long)的(de)(de)(de)牙(ya)(ya)齒(chi)(chi)(chi)數(shu)量(liang)與骨(gu)頭(tou)大小并不呈正比。而每(mei)(mei)塊(kuai)齒(chi)(chi)(chi)骨(gu)約(yue)有(you)14到(dao)17顆(ke)(ke)牙(ya)(ya)齒(chi)(chi)(chi),平均數(shu)量(liang)為(wei)16顆(ke)(ke)。越往嘴部深處,牙(ya)(ya)齒(chi)(chi)(chi)就越短、狹窄、彎曲(qu)。異(yi)特(te)龍(long)的(de)(de)(de)牙(ya)(ya)齒(chi)(chi)(chi)都為(wei)鋸齒(chi)(chi)(chi)狀。這些牙(ya)(ya)齒(chi)(chi)(chi)很容易脫落,所以它們會不斷地生長(chang)(chang)、替(ti)代(dai),并成為(wei)常發現的(de)(de)(de)化石。霸王龍(long)嘴里有(you)60顆(ke)(ke)牙(ya)(ya)齒(chi)(chi)(chi),異(yi)特(te)龍(long)牙(ya)(ya)齒(chi)(chi)(chi)更多,有(you)70顆(ke)(ke),而且每(mei)(mei)顆(ke)(ke)牙(ya)(ya)齒(chi)(chi)(chi)像匕首一(yi)樣鋒利,所有(you)的(de)(de)(de)牙(ya)(ya)齒(chi)(chi)(chi)向后(hou)彎曲(qu),用(yong)于(yu)撕開獵物的(de)(de)(de)肉(rou)。
異(yi)特龍(long)的(de)(de)眼(yan)睛上(shang)方擁有一(yi)對角(jiao)冠(guan)(guan),由延伸的(de)(de)淚骨(gu)所構成(cheng)。角(jiao)冠(guan)(guan)的(de)(de)形狀與大小隨著個體(ti)而不同。鼻骨(gu)的(de)(de)上(shang)方也有一(yi)對低矮的(de)(de)棱脊,并沿者鼻骨(gu),連接到(dao)眼(yan)睛上(shang)的(de)(de)角(jiao)冠(guan)(guan)。這些角(jiao)冠(guan)(guan)可能(neng)覆(fu)蓋者角(jiao)質,并具(ju)有不同的(de)(de)功(gong)能(neng),例如:替眼(yan)睛遮辟(pi)陽光、視覺展示物、以(yi)及物種(zhong)內的(de)(de)打斗行為(問題是它們非常脆弱)。頭顱骨(gu)后上(shang)方也有一(yi)個棱脊,可供(gong)肌肉附著,這特征也可見于暴龍(long)科動物。
淚(lei)骨內側(ce)有凹處,可(ke)能(neng)內藏腺體,例(li)如鹽腺。上顎骨內側(ce)有凹陷(xian)(xian)處,發展的比基礎獸(shou)腳類恐龍(long)的鼻(bi)竇(dou)還好,例(li)如角鼻(bi)龍(long)與(yu)馬什龍(long);這些凹陷(xian)(xian)處可(ke)能(neng)與(yu)嗅覺器官有關(guan),例(li)如犁鼻(bi)器。異特(te)龍(long)腦(nao)殼頂部較(jiao)薄,可(ke)能(neng)為促進腦(nao)部的體溫調(diao)節。
異特龍的頭顱骨(gu)是(shi)由個別的骨(gu)頭所組成(cheng),而骨(gu)頭之(zhi)(zhi)間有(you)可(ke)(ke)活動關節。例如下(xia)(xia)顎的前半(ban)(ban)部與后(hou)半(ban)(ban)部可(ke)(ke)往外彎曲,增加(jia)骨(gu)頭間的空(kong)隙,因(yin)此可(ke)(ke)以吞下(xia)(xia)較大的食物。腦殼與額骨(gu)之(zhi)(zhi)間可(ke)(ke)能也有(you)類似的關節。
借助下(xia)頜(he)靈活的關節,異特龍的嘴可(ke)以張(zhang)得很大,便于撕咬。這對獵物來說是致(zhi)命的攻擊。
異特龍擁有9節頸椎、14節背椎、5節支撐臀部的薦椎。尾椎的數量不明,可能隨者個體大小而不同;詹姆斯·麥迪遜估計異特龍有接近50節尾椎,而葛瑞格利·保羅認為這個數量過多,提出應該不超過45節。頸椎與(yu)(yu)(yu)前段(duan)背(bei)椎有(you)(you)中(zhong)空區域,這(zhe)(zhe)(zhe)種空間(jian)也可見于現代鳥類(lei)(lei),被(bei)認(ren)為(wei)(wei)具有(you)(you)類(lei)(lei)似鳥類(lei)(lei)的(de)氣囊系統,使(shi)用于呼吸作用上。異(yi)(yi)(yi)特龍的(de)肋(lei)骨(gu)寬廣,形(xing)成桶狀胸(xiong)腔,與(yu)(yu)(yu)較原始(shi)的(de)獸腳類(lei)(lei)(例(li)如角鼻龍)不同。異(yi)(yi)(yi)特龍也具有(you)(you)腹(fu)(fu)肋(lei),但不常被(bei)發現,可能有(you)(you)稍微的(de)骨(gu)化。在(zai)一個已公布標本中(zhong),這(zhe)(zhe)(zhe)些腹(fu)(fu)肋(lei)被(bei)發現生前曾(ceng)受過傷(shang)。有(you)(you)一個叉骨(gu)被(bei)保存下來(lai),但直到1996年才被(bei)確認(ren)出來(lai);在(zai)一些案例(li)中(zhong),叉骨(gu)與(yu)(yu)(yu)腹(fu)(fu)肋(lei)則被(bei)混淆。主要的(de)臀(tun)部(bu)骨(gu)頭腸骨(gu)巨(ju)大,恥(chi)骨(gu)有(you)(you)個明顯的(de)尾端,可能作為(wei)(wei)肌肉附著處,以及(ji)身體(ti)躺在(zai)地面時(shi)(shi)的(de)支撐物。在(zai)1976年,麥(mai)迪遜發現克利(li)夫(fu)蘭勞(lao)埃德恐龍采石(shi)場所(suo)發現的(de)異(yi)(yi)(yi)特龍化石(shi),有(you)(you)接近一半(ban)個體(ti)的(de)兩(liang)個恥(chi)骨(gu)上端,并(bing)未互相固定者(zhe)。由于這(zhe)(zhe)(zhe)個特征(zheng)與(yu)(yu)(yu)體(ti)型無關,因此麥(mai)迪遜認(ren)為(wei)(wei)這(zhe)(zhe)(zhe)是種兩(liang)性(xing)異(yi)(yi)(yi)形(xing),雌性(xing)個體(ti)的(de)恥(chi)骨(gu)上端沒有(you)(you)互相固定著,可使(shi)產卵時(shi)(shi)更為(wei)(wei)順利(li)。然而,這(zhe)(zhe)(zhe)個理論并(bing)未引起進一步(bu)的(de)討論。
與(yu)后(hou)肢相比(bi),異(yi)特龍(long)的(de)前(qian)肢相當短,但(dan)比(bi)暴龍(long)要(yao)長(chang)(chang)很(hen)多,約是(shi)(shi)后(hou)肢長(chang)(chang)度(du)的(de)35%。每個手(shou)部具有三根(gen)手(shou)指(zhi),以及大型、大幅彎曲的(de)指(zhi)爪。異(yi)特龍(long)的(de)前(qian)肢強壯,與(yu)其他的(de)獸腳類(lei)恐龍(long)相比(bi),它們(men)的(de)前(qian)肢適合抓(zhua)握(wo)一定距離(li)內的(de)獵物,或(huo)是(shi)(shi)將(jiang)獵物拉近。前(qian)臂稍短于上臂,肱(gong)骨與(yu)尺(chi)骨的(de)比(bi)例(li)為1:1.2。手(shou)腕(wan)具有類(lei)似半(ban)新(xin)(xin)月(yue)形的(de)腕(wan)骨,手(shou)盜龍(long)類(lei)的(de)腕(wan)骨更(geng)為接近半(ban)新(xin)(xin)月(yue)形。異(yi)特龍(long)的(de)三根(gen)手(shou)指(zhi)中,內側第一根(gen)手(shou)指(zhi)是(shi)(shi)最長(chang)(chang)的(de)。指(zhi)爪的(de)狀態顯示手(shou)指(zhi)可能用來鉤(gou)住東西。
通過研究遺骸,我們了解到許多(duo)恐龍(long)(long)身體(ti)龐(pang)大(da),但(dan)這不意味著(zhu)(zhu)他(ta)們很(hen)聰明(ming)。馬門(men)溪龍(long)(long)活著(zhu)(zhu)的(de)(de)時候約有四(si)五十噸(dun)重,而腦(nao)子(zi)重量只有500克左右。又如(ru)劍龍(long)(long),他(ta)的(de)(de)身軀有大(da)象那么大(da),而腦(nao)子(zi)卻小得如(ru)約100克的(de)(de)核(he)桃。異特(te)龍(long)(long)也長著(zhu)(zhu)龐(pang)大(da)的(de)(de)身體(ti),但(dan)據(ju)推測(ce),他(ta)的(de)(de)大(da)腦(nao)可能很(hen)發達,是侏(zhu)羅紀時期智(zhi)商最(zui)高的(de)(de)大(da)型肉食恐龍(long)(long),這也給它(ta)們的(de)(de)群居提供了方便。
異(yi)特(te)龍(long)的(de)(de)大(da)(da)量化石幾乎涵蓋了所有的(de)(de)年齡(ling)(ling)層,這使得(de)科學家們可以(yi)研(yan)究(jiu)異(yi)特(te)龍(long)的(de)(de)生(sheng)長模式與年齡(ling)(ling)上(shang)限。在科羅拉多州發現(xian)的(de)(de)一堆壓碎(sui)的(de)(de)蛋化石,可能屬于異(yi)特(te)龍(long),這是(shi)目前所發現(xian)最年幼(you)的(de)(de)異(yi)特(te)龍(long)化石。根據四肢(zhi)骨頭(tou)的(de)(de)組織(zhi)學分析,異(yi)特(te)龍(long)的(de)(de)年齡(ling)(ling)上(shang)限大(da)(da)約(yue)為22到28歲(sui),相當于其他(ta)大(da)(da)型獸腳(jiao)類(lei)恐(kong)龍(long)(例(li)如暴龍(long))。異(yi)特(te)龍(long)的(de)(de)最高生(sheng)長率大(da)(da)約(yue)發生(sheng)在15歲(sui)時,一年可以(yi)增加148公(gong)斤的(de)(de)體重(zhong)。
已在(zai)一(yi)個(ge)(ge)出土於(wu)克利夫蘭(lan)勞埃(ai)德的(de)(de)異特(te)龍(long)脛(jing)骨(gu),發(fa)現了(le)骨(gu)髓(sui)(sui)(sui)骨(gu)組(zu)(zu)織(zhi)(zhi)。除了(le)異特(te)龍(long)以外(wai),腱龍(long)與暴龍(long)也發(fa)現了(le)骨(gu)髓(sui)(sui)(sui)骨(gu)。骨(gu)髓(sui)(sui)(sui)骨(gu)只(zhi)存(cun)在(zai)于產卵的(de)(de)雌性(xing)鳥類身上,骨(gu)髓(sui)(sui)(sui)骨(gu)富(fu)含鈣,可用(yong)來制(zhi)造(zao)蛋(dan)殼的(de)(de)。異特(te)龍(long)的(de)(de)骨(gu)髓(sui)(sui)(sui)骨(gu)組(zu)(zu)織(zhi)(zhi),顯示(shi)該個(ge)(ge)體是雌性(xing)的(de)(de),而且正(zheng)在(zai)繁衍(yan)期(qi)中。這(zhe)個(ge)(ge)雌性(xing)異特(te)龍(long)估計是在(zai)10歲時死亡(wang),從此顯示(shi)異特(te)龍(long)在(zai)完全(quan)成長前,就(jiu)已達(da)到性(xing)成熟。
一個具(ju)有(you)幾乎完(wan)整后肢的(de)(de)幼(you)年(nian)(nian)異(yi)(yi)特(te)龍標(biao)本,顯(xian)示(shi)幼(you)年(nian)(nian)個體(ti)的(de)(de)后肢比例較成(cheng)年(nian)(nian)個體(ti)長(chang),而且后肢下半(ban)部(bu)(小腿(tui)(tui)與腳(jiao)部(bu))長(chang)於大(da)腿(tui)(tui)部(bu)分。這些(xie)差別(bie)顯(xian)示(shi)年(nian)(nian)輕異(yi)(yi)特(te)龍的(de)(de)移動速(su)度較快,并具(ju)有(you)不同于成(cheng)年(nian)(nian)個體(ti)的(de)(de)獵食(shi)方式,例如追趕小型(xing)獵物,而成(cheng)年(nian)(nian)個體(ti)則改采(cai)伏擊方式捕食(shi)大(da)型(xing)的(de)(de)獵物。隨者異(yi)(yi)特(te)龍的(de)(de)成(cheng)長(chang),它們的(de)(de)大(da)腿(tui)(tui)骨頭變(bian)(bian)得(de)更(geng)厚(hou)、更(geng)寬,而橫剖面變(bian)(bian)得(de)較不圓形,隨者肌(ji)肉附著點(dian)的(de)(de)改變(bian)(bian),肌(ji)肉相對更(geng)短,腿(tui)(tui)部(bu)的(de)(de)成(cheng)長(chang)減緩。這些(xie)改變(bian)(bian)顯(xian)示(shi)幼(you)年(nian)(nian)異(yi)(yi)特(te)龍的(de)(de)腿(tui)(tui)部(bu),承受的(de)(de)應(ying)力較成(cheng)年(nian)(nian)異(yi)(yi)特(te)龍小,幼(you)年(nian)(nian)異(yi)(yi)特(te)龍可能(neng)以更(geng)規(gui)律的(de)(de)速(su)度前進。
異特龍被認為是種主動攻擊的大型掠食者。根據蜥腳類恐龍骨頭上的異特龍齒痕,以及與蜥腳類化石一起發現的零散異特龍牙齒來判斷,異特龍可能以蜥腳類恐龍為獵食對象,或是搜尋它們的尸體為食。另外有明確證據顯示異特龍曾經攻擊過劍龍,例如一個異特龍的尾椎上有個部分痊愈的傷口,這個被刺穿傷口的形狀符合劍龍的尾刺;另外,在一個劍龍的頸部骨板上有個U形的傷口,與異特龍的嘴部形狀符合。在1988年,葛瑞格利·保羅(Gregory Paul)提出異特龍不可能以蜥腳類恐龍為食,除非采取群體方式獵食;因為異特龍的頭部大小屬中型、牙齒相對較小,體型也無法與同時代的大型蜥腳類恐龍相比。另一個可能則是異特龍以幼年蜥腳類恐龍為獵食對象,而不獵食完全成長的蜥腳類恐龍。90年代與2000年的研究可能解答了這個問題。羅伯特·巴克(Robert T. Bakker)將異特龍與一些生存于新生代肉食性哺乳類相比,發現類似的(de)(de)適應演(yan)化,例如:顎(e)(e)部肌肉(rou)的(de)(de)縮小、頸部肌肉(rou)的(de)(de)增(zeng)大(da)、以及將顎(e)(e)部左(zuo)右撐開的(de)(de)能(neng)力(li)。雖(sui)然(ran)異(yi)特龍(long)的(de)(de)牙齒(chi)并(bing)非如這(zhe)些哺乳類呈軍刀狀,巴克提出(chu)了另一(yi)種異(yi)特龍(long)的(de)(de)攻(gong)(gong)擊方式:上顎(e)(e)的(de)(de)短(duan)牙齒(chi)會形成(cheng)類似鋸(ju)子的(de)(de)小型鋸(ju)齒(chi)表面(mian),可切入獵物(wu)肉(rou)體。這(zhe)種型態(tai)的(de)(de)顎(e)(e)部可使(shi)異(yi)特龍(long)采(cai)取撕(si)咬(yao)方式攻(gong)(gong)擊大(da)型獵物(wu),消耗獵物(wu)的(de)(de)體力(li)。
埃米莉·雷菲爾德(Emily J. Rayfield)等(deng)人使用(yong)(yong)有限元(yuan)分析,研究(jiu)(jiu)(jiu)了異(yi)特(te)(te)龍的(de)(de)(de)(de)頭(tou)顱(lu)(lu)骨(gu),也得到了類(lei)似的(de)(de)(de)(de)結果(guo)。根據其中(zhong)的(de)(de)(de)(de)生物(wu)(wu)力(li)學研究(jiu)(jiu)(jiu)結果(guo),異(yi)特(te)(te)龍的(de)(de)(de)(de)頭(tou)顱(lu)(lu)骨(gu)非常強壯,咬(yao)合力(li)相當大(da)(da)。異(yi)特(te)(te)龍的(de)(de)(de)(de)咬(yao)合力(li)可以達到3-8噸,而且它們(men)的(de)(de)(de)(de)頭(tou)顱(lu)(lu)可承受約55000牛頓來(lai)(lai)自于齒列的(de)(de)(de)(de)垂直壓強。這個研究(jiu)(jiu)(jiu)也提出異(yi)特(te)(te)龍使用(yong)(yong)頭(tou)部(bu)來(lai)(lai)撞擊(ji)獵物(wu)(wu),并(bing)張開大(da)(da)口、撕(si)咬(yao)獵物(wu)(wu)。這個研究(jiu)(jiu)(jiu)認(ren)為(wei)異(yi)特(te)(te)龍的(de)(de)(de)(de)頭(tou)部(bu)結構允(yun)許它們(men)采取(qu)不(bu)同的(de)(de)(de)(de)獵食模式(shi)來(lai)(lai)攻(gong)擊(ji)不(bu)同的(de)(de)(de)(de)獵物(wu)(wu):它們(men)的(de)(de)(de)(de)頭(tou)部(bu)較(jiao)(jiao)(jiao)輕型,可攻(gong)擊(ji)較(jiao)(jiao)(jiao)小(xiao)、較(jiao)(jiao)(jiao)靈活(huo)的(de)(de)(de)(de)鳥(niao)腳類(lei)恐龍;但頭(tou)部(bu)有足(zu)夠的(de)(de)(de)(de)強度承受撞擊(ji),可允(yun)取(qu)它們(men)采取(qu)伏擊(ji)方(fang)式(shi)攻(gong)擊(ji)較(jiao)(jiao)(jiao)大(da)(da)型的(de)(de)(de)(de)劍龍科與蜥腳類(lei)恐龍。
其(qi)他(ta)的(de)科(ke)學家則(ze)(ze)對這(zhe)(zhe)個(ge)研(yan)究表示異(yi)議(yi),他(ta)們(men)認(ren)為現(xian)(xian)存生(sheng)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)中(zhong)沒(mei)有(you)采取(qu)撞擊方(fang)(fang)式(shi)獵(lie)(lie)(lie)食(shi)的(de)動物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu),并提出異(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)頭(tou)部有(you)足(zu)(zu)夠的(de)強(qiang)(qiang)度,應(ying)可(ke)承(cheng)受獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)掙扎的(de)力量。雷菲爾(er)德等人(ren)對異(yi)議(yi)提出回應(ying),他(ta)們(men)承(cheng)認(ren)現(xian)(xian)存生(sheng)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)中(zhong)沒(mei)有(you)類(lei)(lei)(lei)似異(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)動物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu),但異(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)齒(chi)列(lie)適合這(zhe)(zhe)種(zhong)攻擊方(fang)(fang)式(shi),而(er)(er)它們(men)的(de)頭(tou)部結構可(ke)保護上顎、減(jian)低承(cheng)受力量。另(ling)一(yi)種(zhong)可(ke)能(neng)則(ze)(ze)是(shi)(shi),獸腳(jiao)類(lei)(lei)(lei)恐(kong)(kong)(kong)龍(long)(long)(long)(long)(long)(例(li)如異(yi)特(te)(te)龍(long)(long)(long)(long)(long))不必費力將(jiang)獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)殺死,而(er)(er)是(shi)(shi)從活生(sheng)的(de)蜥腳(jiao)類(lei)(lei)(lei)恐(kong)(kong)(kong)龍(long)(long)(long)(long)(long)身上咬下足(zu)(zu)夠的(de)肉塊,肉塊的(de)大小(xiao)(xiao)只需維(wei)持獵(lie)(lie)(lie)食(shi)者生(sheng)存即可(ke)。這(zhe)(zhe)種(zhong)獵(lie)(lie)(lie)食(shi)方(fang)(fang)式(shi)也使獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)有(you)機會痊愈,而(er)(er)獵(lie)(lie)(lie)食(shi)者也可(ke)能(neng)以(yi)(yi)類(lei)(lei)(lei)似的(de)方(fang)(fang)式(shi)再度獵(lie)(lie)(lie)食(shi)。另(ling)外,鳥(niao)(niao)腳(jiao)類(lei)(lei)(lei)恐(kong)(kong)(kong)龍(long)(long)(long)(long)(long)是(shi)(shi)當地最常(chang)見(jian)的(de)獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu),因(yin)此(ci)異(yi)特(te)(te)龍(long)(long)(long)(long)(long)可(ke)能(neng)采偷襲(xi)方(fang)(fang)式(shi)獵(lie)(lie)(lie)食(shi)鳥(niao)(niao)腳(jiao)類(lei)(lei)(lei)恐(kong)(kong)(kong)龍(long)(long)(long)(long)(long),使用前肢(zhi)(zhi)抓住獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu),并咬斷獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)喉(hou)嚨(long)的(de)氣管(guan),類(lei)(lei)(lei)似今日的(de)大型貓科(ke)動物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)。異(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)前肢(zhi)(zhi)強(qiang)(qiang)壯,能(neng)夠抓緊獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu),所以(yi)(yi)這(zhe)(zhe)個(ge)獵(lie)(lie)(lie)食(shi)方(fang)(fang)式(shi)是(shi)(shi)可(ke)能(neng)成立的(de)。其(qi)他(ta)影響進食(shi)方(fang)(fang)式(shi)的(de)因(yin)素(su)包含:眼睛、前肢(zhi)(zhi)、以(yi)(yi)及后肢(zhi)(zhi)。異(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)頭(tou)部形狀將(jiang)立體(ti)(ti)視覺限制在20°的(de)范圍(wei)內,略小(xiao)(xiao)于(yu)現(xian)(xian)代鱷魚。如同鱷魚,這(zhe)(zhe)個(ge)范圍(wei)已足(zu)(zu)夠異(yi)特(te)(te)龍(long)(long)(long)(long)(long)判斷獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)的(de)距離(li)與攻擊時機。相(xiang)較于(yu)其(qi)他(ta)獸腳(jiao)類(lei)(lei)(lei)恐(kong)(kong)(kong)龍(long)(long)(long)(long)(long),異(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)前肢(zhi)(zhi)適合抓住一(yi)定距離(li)的(de)獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu),還有(you)將(jiang)獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)拉近;而(er)(er)指爪的(de)構造(zao)顯示它們(men)可(ke)用來勾取(qu)物(wu)(wu)(wu)(wu)(wu)(wu)(wu)(wu)體(ti)(ti)。經推(tui)算,異(yi)特(te)(te)龍(long)(long)(long)(long)(long)的(de)最高奔跑(pao)速(su)度可(ke)達每小(xiao)(xiao)時30到55公里(li)。
長(chang)久(jiu)以來,半科(ke)學文獻(xian)與(yu)大眾讀(du)物都(dou)將(jiang)異特龍(long)(long)描述成以群體方(fang)式(shi)獵食(shi),并以蜥腳類(lei)恐龍(long)(long)與(yu)其他(ta)大型恐龍(long)(long)為(wei)獵食(shi)對象。羅伯特·巴(ba)克(ke)(Robert T.Bakker)從(cong)脫落的(de)(de)牙齒(chi)、大型獵物的(de)(de)被(bei)咬(yao)過骨(gu)頭研判,異特龍(long)(long)具有親代養育的(de)(de)社會行為(wei)。巴(ba)克(ke)認為(wei)成年異特龍(long)(long)將(jiang)食(shi)物帶到(dao)巢穴中,以供幼年異特龍(long)(long)食(shi)用,并防止其他(ta)肉食(shi)性動物找到(dao)它們(men)的(de)(de)食(shi)物。
研究提出(chu)異特(te)(te)龍與其他獸腳類(lei)恐龍具有侵略性的(de)(de)(de)(de)物(wu)種內行為(wei)(wei)(wei),而非(fei)合(he)作(zuo)性的(de)(de)(de)(de)行為(wei)(wei)(wei),如同其他的(de)(de)(de)(de)雙(shuang)弓動(dong)物(wu)。一個研究則(ze)推(tui)論獸腳類(lei)恐龍會(hui)合(he)作(zuo)獵食(shi)(shi),而非(fei)個別獵食(shi)(shi);這(zhe)種行為(wei)(wei)(wei)在(zai)脊(ji)椎(zhui)動(dong)物(wu)中較(jiao)少見,而現(xian)存雙(shuang)弓動(dong)物(wu)(包(bao)括蜥蜴(yi)、鱷(e)魚、鳥類(lei))很(hen)少合(he)作(zuo)獵食(shi)(shi)。許多現(xian)代的(de)(de)(de)(de)掠食(shi)(shi)性雙(shuang)弓動(dong)物(wu)是領域性,會(hui)將侵入領地的(de)(de)(de)(de)同類(lei)殺(sha)死(si)、并(bing)吞食(shi)(shi)它們的(de)(de)(de)(de)尸體;另外(wai)當聚集(ji)在(zai)食(shi)(shi)物(wu)周圍(wei)時,它們會(hui)將企圖搶先的(de)(de)(de)(de)較(jiao)小個體殺(sha)死(si)。克利夫蘭勞埃德采石場(chang)的(de)(de)(de)(de)大量異特(te)(te)龍化石可(ke)能(neng)(neng)源于(yu)它們在(zai)同類(lei)相(xiang)食(shi)(shi)時被淹死(si)。這(zhe)也可(ke)以解釋異特(te)(te)龍化石中,幼年(nian)與近(jin)成年(nian)個體所(suo)占的(de)(de)(de)(de)比(bi)例較(jiao)高;因為(wei)(wei)(wei)在(zai)現(xian)代的(de)(de)(de)(de)鱷(e)魚與科(ke)莫多龍中,幼年(nian)與近(jin)成年(nian)個體較(jiao)少在(zai)聚食(shi)(shi)地點中被殺(sha)死(si)。這(zhe)理論也可(ke)解釋巴克所(suo)發(fa)現(xian)的(de)(de)(de)(de)巢(chao)穴(xue)狀(zhuang)況。有些(xie)證據顯示(shi)異特(te)(te)龍具有同類(lei)相(xiang)食(shi)(shi)的(de)(de)(de)(de)行為(wei)(wei)(wei),例如肋骨(gu)碎片上(shang)有脫落的(de)(de)(de)(de)同類(lei)牙齒、一個肩胛骨(gu)上(shang)有可(ke)能(neng)(neng)的(de)(de)(de)(de)齒痕、巴克所(suo)發(fa)現(xian)的(de)(de)(de)(de)巢(chao)穴(xue)中的(de)(de)(de)(de)異特(te)(te)龍骨(gu)骸可(ke)能(neng)(neng)遭到同類(lei)相(xiang)食(shi)(shi)。
一個針對異(yi)特(te)(te)(te)龍腦(nao)(nao)部(bu)的(de)電腦(nao)(nao)斷層掃描,發現它(ta)(ta)們(men)的(de)腦(nao)(nao)部(bu)與鱷魚和鳥類(lei)有較多的(de)共(gong)同(tong)點。前庭(ting)器(qi)官的(de)結構(gou)顯示它(ta)(ta)們(men)的(de)頭部(bu)保持在幾乎水平的(de)位置,而非朝上或(huo)朝下。內耳的(de)結構(gou)類(lei)似鱷魚,所以異(yi)特(te)(te)(te)龍可(ke)能(neng)容易(yi)聽到低頻的(de)聲音,也可(ke)以聽到細微的(de)聲音。異(yi)特(te)(te)(te)龍的(de)嗅球(qiu)大,可(ke)能(neng)適合(he)感(gan)覺(jue)氣味。
早(zao)在1869年,科(ke)羅拉(la)多州格蘭比郡附近的(de)中(zhong)央公園d當(dang)地居民(min)將(jiang)(jiang)(jiang)一個(ge)馬蹄化石(shi)交給了費迪(di)南德·范迪(di)威爾·海登(Ferdinand Vandiveer Hayden);該地可能屬(shu)于莫里遜組。海登將(jiang)(jiang)(jiang)這(zhe)標本交給約(yue)瑟(se)夫(fu)(fu)·萊迪(di)(Joseph Leidy),萊迪(di)發現這(zhe)個(ge)"馬蹄"化石(shi)其實是半節尾椎(zhui)骨。約(yue)瑟(se)夫(fu)(fu)·萊迪(di)起初暫時(shi)將(jiang)(jiang)(jiang)它歸類為歐洲雜肋龍(long)的(de)一個(ge)種(Poicilopleurodon valens)。萊迪(di)后來將(jiang)(jiang)(jiang)它建立(li)為一個(ge)新的(de)屬(shu),腔軀龍(long)(Antrodemus)。
異特(te)(te)龍的(de)原型標本(編號YPM 1930)被(bei)發現(xian)于科羅拉(la)多(duo)州卡農城(cheng)北方的(de)花園(yuan)公園(yuan),由(you)一(yi)(yi)(yi)小群破(po)碎(sui)(sui)骨(gu)(gu)頭所構成,包(bao)含三節脊椎、一(yi)(yi)(yi)個(ge)肋骨(gu)(gu)碎(sui)(sui)片(pian)、一(yi)(yi)(yi)顆牙齒、一(yi)(yi)(yi)個(ge)趾骨(gu)(gu)、以及(ji)右肱骨(gu)(gu)主干部(bu)分;而右肱骨(gu)(gu)最常被(bei)后來的(de)研究提及(ji)。在1877年(nian),奧(ao)塞內爾·查利斯·馬什(Othniel Charles Marsh)根(gen)據(ju)這(zhe)些化石,把(ba)這(zhe)種生物定名(ming)為異特(te)(te)龍,并把(ba)其(qi)模(mo)式種正式命(ming)名(ming)為脆(cui)弱異特(te)(te)龍(Allosaurus fragilis)。種名(ming)fragilis來自拉(la)丁語,意即"脆(cui)弱的(de)",是指它們脊椎骨(gu)(gu)的(de)輕盈特(te)(te)點。
在18世紀后(hou)期的(de)(de)(de)化(hua)石(shi)戰爭(zheng)期間(jian),馬什(shen)與(yu)(yu)愛德華·德林克·科(ke)普(Edward Drinker Cope)之間(jian)有過激烈的(de)(de)(de)競爭(zheng)。兩(liang)人曾(ceng)根據許多(duo)零散、相似的(de)(de)(de)化(hua)石(shi)建立(li)了數個屬(shu),但(dan)之后(hou)被證明(ming)屬(shu)于異特龍(long),使(shi)得異特龍(long)的(de)(de)(de)發現與(yu)(yu)早期研(yan)究非常復(fu)雜。兩(liang)人所建立(li)的(de)(de)(de)名稱包含:馬什(shen)命名的(de)(de)(de)Creosaurus(意(yi)為"肌肉蜥蜴(yi)(yi)")、Labrosaurus(意(yi)為"貪吃的(de)(de)(de)蜥蜴(yi)(yi)")、以(yi)及(ji)科(ke)普命名的(de)(de)(de)Epanterias(意(yi)為"拱起(qi)的(de)(de)(de)")。
在(zai)(zai)競(jing)爭(zheng)的(de)(de)(de)過程中(zhong),科(ke)(ke)普與馬(ma)什并(bing)沒(mei)有(you)(you)持續地進行他們與他們下(xia)屬(shu)的(de)(de)(de)挖(wa)(wa)掘(jue)工作。舉例而(er)言(yan),班杰明(ming)·福蘭克林·馬(ma)奇(Benjamin Franklin Mudge)在(zai)(zai)科(ke)(ke)羅拉多州(zhou)花(hua)園(yuan)公(gong)園(yuan)發(fa)現(xian)(xian)異(yi)特(te)龍(long)的(de)(de)(de)原(yuan)型標(biao)本(ben)后,馬(ma)什便轉向懷俄明(ming)州(zhou)進行新(xin)的(de)(de)(de)挖(wa)(wa)掘(jue)工作;而(er)在(zai)(zai)1883年(nian)(nian),M.P.Felch重(zhong)新(xin)開(kai)始花(hua)園(yuan)公(gong)園(yuan)的(de)(de)(de)挖(wa)(wa)掘(jue)工作后,卻發(fa)現(xian)(xian)了(le)一個(ge)幾乎完(wan)整的(de)(de)(de)異(yi)特(te)龍(long)化石,以(yi)及數個(ge)部分骸骨(gu)。另外,科(ke)(ke)普的(de)(de)(de)一個(ge)挖(wa)(wa)掘(jue)工人H.F.Hubbell,在(zai)(zai)1879年(nian)(nian)于懷俄明(ming)州(zhou)的(de)(de)(de)科(ke)(ke)摩崖(ya)發(fa)現(xian)(xian)了(le)一個(ge)異(yi)特(te)龍(long)標(biao)本(ben)(編(bian)號(hao)AMNH 5753),但他沒(mei)有(you)(you)提到化石的(de)(de)(de)完(wan)整程度,所(suo)(suo)以(yi)科(ke)(ke)普從未看過這個(ge)化石。在(zai)(zai)1903年(nian)(nian),科(ke)(ke)普死后數年(nian)(nian),這個(ge)標(biao)本(ben)被發(fa)現(xian)(xian)是當時(shi)最完(wan)整的(de)(de)(de)獸(shou)(shou)腳(jiao)類恐龍(long)之(zhi)一,并(bing)在(zai)(zai)1908年(nian)(nian)開(kai)始展覽。在(zai)(zai)一個(ge)由查爾斯·耐特(te)(Charles R.Knight)所(suo)(suo)繪制的(de)(de)(de)圖(tu)畫中(zhong),編(bian)號(hao)AMNH 5753的(de)(de)(de)異(yi)特(te)龍(long)跨(kua)越在(zai)(zai)一只迷(mi)(mi)惑龍(long)身上,吞食著迷(mi)(mi)惑龍(long)的(de)(de)(de)尸體(ti)。雖然這是第(di)一次將獸(shou)(shou)腳(jiao)類恐龍(long)描繪成站立姿態,但當時(shi)并(bing)沒(mei)有(you)(you)科(ke)(ke)學證據可以(yi)支持。
異特(te)龍(long)名(ming)稱(cheng)(cheng)的(de)重(zhong)復使得研(yan)究變(bian)的(de)復雜,并(bing)隨者馬什與科普的(de)競(jing)爭而惡化(hua)。在(zai)(zai)當時便有(you)一(yi)些(xie)(xie)科學家(jia),例如塞繆爾(er)(er)·溫德爾(er)(er)·威(wei)利斯(si)頓(Samuel Wendell Williston),提出有(you)太多相關名(ming)稱(cheng)(cheng)被(bei)重(zhong)復建立。在(zai)(zai)1901年(nian),威(wei)利斯(si)頓便指出馬什自己也無法(fa)分(fen)辨出異特(te)龍(long)與Creosaurus的(de)差(cha)異。查爾(er)(er)斯(si)·懷特(te)尼·吉(ji)(ji)爾(er)(er)摩(mo)(mo)爾(er)(er)(Charles W.Gilmore)在(zai)(zai)1920年(nian)嘗(chang)試將這(zhe)(zhe)些(xie)(xie)復雜的(de)名(ming)稱(cheng)(cheng)整理、歸類。吉(ji)(ji)爾(er)(er)摩(mo)(mo)爾(er)(er)認(ren)為萊迪用(yong)(yong)來(lai)命名(ming)腔(qiang)(qiang)(qiang)軀龍(long)的(de)尾椎(zhui),其實跟異特(te)龍(long)的(de)尾椎(zhui)一(yi)樣;因(yin)為腔(qiang)(qiang)(qiang)軀龍(long)較早(zao)命名(ming),所(suo)以取(qu)代(dai)異特(te)龍(long)。在(zai)(zai)接下來(lai)的(de)50年(nian),腔(qiang)(qiang)(qiang)軀龍(long)取(qu)代(dai)異特(te)龍(long),成為正式的(de)名(ming)稱(cheng)(cheng),直到詹姆(mu)斯(si)·麥(mai)(mai)迪遜在(zai)(zai)克利夫蘭(lan)勞埃德采石場發現(xian)新的(de)異特(te)龍(long)化(hua)石,并(bing)出腔(qiang)(qiang)(qiang)軀龍(long)的(de)化(hua)石材(cai)料無法(fa)鑒定,發現(xian)地(di)點也不清楚,應該(gai)采用(yong)(yong)異特(te)龍(long)這(zhe)(zhe)名(ming)稱(cheng)(cheng)。腔(qiang)(qiang)(qiang)軀龍(long)為非正式的(de)用(yong)(yong)法(fa),只用(yong)(yong)在(zai)(zai)區分(fen)吉(ji)(ji)爾(er)(er)摩(mo)(mo)爾(er)(er)與麥(mai)(mai)迪遜兩人(ren)重(zhong)建的(de)不同形態頭顱(lu)骨。
早在(zai)1927年(nian)(nian)(nian)(nian)開(kai)(kai)始,猶他州艾麥(mai)里縣的(de)(de)(de)克(ke)利(li)夫蘭勞埃德(de)(de)恐(kong)龍采(cai)石(shi)(shi)(shi)場(chang)便有了零(ling)散的(de)(de)(de)發現,威廉·斯托克(ke)斯(William J. Stokes)在(zai)1945年(nian)(nian)(nian)(nian)于(yu)《科(ke)學》雜志(zhi)描述了這(zhe)(zhe)個采(cai)石(shi)(shi)(shi)場(chang),但直到(dao)60年(nian)(nian)(nian)(nian)代,才開(kai)(kai)始了大(da)型的(de)(de)(de)挖掘(jue)計畫(hua)。在(zai)1960年(nian)(nian)(nian)(nian)到(dao)1965年(nian)(nian)(nian)(nian)期間,在(zai)接近(jin)40個機構的(de)(de)(de)合(he)力(li)挖掘(jue)之下,該(gai)采(cai)石(shi)(shi)(shi)場(chang)出(chu)土(tu)了數(shu)千塊骨(gu)頭(tou)。克(ke)利(li)夫蘭勞埃德(de)(de)采(cai)石(shi)(shi)(shi)場(chang)的(de)(de)(de)著名原因包含:大(da)部分骨(gu)頭(tou)都屬于(yu)脆弱異特龍,例(li)如在(zai)2006年(nian)(nian)(nian)(nian),73個出(chu)土(tu)的(de)(de)(de)恐(kong)龍個體中(zhong),至(zhi)少(shao)有46個屬于(yu)脆弱異特龍;這(zhe)(zhe)些化(hua)石(shi)(shi)(shi)不呈(cheng)天然(ran)狀態,而且互相混合(he);將近(jin)有10多(duo)個科(ke)學研(yan)究(jiu)討論了該(gai)地(di)(di)點的(de)(de)(de)化(hua)石(shi)(shi)(shi)埋(mai)葬狀況,形成(cheng)(cheng)不同(tong)、互相矛盾的(de)(de)(de)解釋。對(dui)于(yu)該(gai)地(di)(di)的(de)(de)(de)成(cheng)(cheng)因,包含大(da)群(qun)動物深(shen)陷在(zai)泥濘之中(zhong)、乾(qian)旱導(dao)致大(da)群(qun)動物困(kun)在(zai)水洼(wa)之中(zhong)。無(wu)論正確的(de)(de)(de)成(cheng)(cheng)因為(wei)何(he),當地(di)(di)發現的(de)(de)(de)大(da)量異特龍化(hua)石(shi)(shi)(shi)使(shi)得科(ke)學家可以(yi)詳細地(di)(di)研(yan)究(jiu)它(ta)們(men),使(shi)得異特龍成(cheng)(cheng)為(wei)了解最多(duo)的(de)(de)(de)獸腳類恐(kong)龍之一。該(gai)地(di)(di)所(suo)出(chu)土(tu)的(de)(de)(de)異特龍化(hua)石(shi)(shi)(shi)幾(ji)乎包含各(ge)種年(nian)(nian)(nian)(nian)齡(ling)與大(da)小,身長范(fan)圍從(cong)1公(gong)尺到(dao)9公(gong)尺。
自從麥迪遜(xun)的(de)專題論(lun)文公布以來,已有(you)許多(duo)研究(jiu)討(tao)論(lun)異(yi)特(te)龍(long)的(de)古(gu)生(sheng)物學以及(ji)古(gu)生(sheng)態學。這些(xie)研究(jiu)涵蓋了異(yi)特(te)龍(long)的(de)骨骼(ge)差(cha)異(yi)、生(sheng)長模(mo)式(shi)、頭顱骨重建、獵食(shi)模(mo)式(shi)、腦部構造、以及(ji)群居生(sheng)活與親代(dai)養育的(de)可能(neng)性。早期異(yi)特(te)龍(long)標(biao)本的(de)重新研究(jiu)、在葡(pu)萄牙新發現的(de)化石、以及(ji)數個非常(chang)完(wan)整(zheng)的(de)標(biao)本也有(you)助于對異(yi)特(te)龍(long)的(de)了解(jie)。
在1991年發(fa)現的"大(da)(da)艾(ai)爾(er)"標本(編號MOR 593),是(shi)最(zui)著名的異特龍化石(shi)之一。"大(da)(da)艾(ai)爾(er)"是(shi)個相(xiang)當完(wan)整(zheng)的天然狀態標本,接近(jin)95%完(wan)整(zheng)度,身長(chang)約8米。"大(da)(da)艾(ai)爾(er)"最(zui)初(chu)是(shi)由(you)(you)卡比(bi)·希伯(Kirby Siber)所率領的瑞(rui)士(shi)團隊發(fa)現于懷(huai)俄明州的比(bi)格霍恩縣,并(bing)由(you)(you)懷(huai)俄明大(da)(da)學地理博(bo)物館與(yu)洛磯山博(bo)物館共同(tong)挖掘出(chu)土。因為(wei)該化石(shi)相(xiang)當完(wan)整(zheng),因此取(qu)了個昵稱:"大(da)(da)艾(ai)爾(er)"。發(fa)現"大(da)(da)艾(ai)爾(er)"的瑞(rui)士(shi)團隊后來在同(tong)一地點(dian)發(fa)現另一異特龍化石(shi),并(bing)取(qu)名為(wei)"大(da)(da)艾(ai)爾(er)二號",這(zhe)具化石(shi)是(shi)到目前為(wei)止(zhi),保存狀態最(zui)好的異特龍化石(shi)。
"大(da)(da)艾爾(er)(er)"的(de)體型小于脆(cui)弱異特(te)龍的(de)平均大(da)(da)小,可能(neng)是(shi)個(ge)(ge)近成(cheng)年體,估計(ji)只成(cheng)長(chang)到了(le)87%,或是(shi)另一(yi)較小的(de)種(zhong)。"大(da)(da)艾爾(er)(er)"由布倫特(te)·布萊(lai)特(te)豪普特(te)(Brent Breithaupt)是(shi)在1996年所敘述(shu)。其(qi)中有19個(ge)(ge)骨(gu)(gu)(gu)頭(tou)(tou)(tou)是(shi)斷(duan)裂的(de),呈現出感(gan)染(ran)(ran)的(de)跡象,這(zhe)可能(neng)導致"大(da)(da)艾爾(er)(er)"的(de)死亡。這(zhe)些感(gan)染(ran)(ran)的(de)骨(gu)(gu)(gu)頭(tou)(tou)(tou)包含五個(ge)(ge)肋(lei)骨(gu)(gu)(gu)、五節脊椎(zhui)、四個(ge)(ge)腳部(bu)骨(gu)(gu)(gu)頭(tou)(tou)(tou);數(shu)個(ge)(ge)骨(gu)(gu)(gu)頭(tou)(tou)(tou)則具(ju)有骨(gu)(gu)(gu)髓炎。右腳上的(de)感(gan)染(ran)(ran)與傷口可能(neng)影響了(le)"大(da)(da)艾爾(er)(er)"的(de)行走(zou),從(cong)步態(tai)的(de)改變研判,右腳的(de)傷口可能(neng)感(gan)染(ran)(ran)了(le)另一(yi)只腳。
異特(te)龍是(shi)美國(guo)西部(bu)莫里(li)遜組地(di)(di)(di)層中最(zui)常(chang)見(jian)的(de)(de)大型獸腳亞(ya)目化石,它(ta)們位在(zai)該地(di)(di)(di)食(shi)物(wu)鏈的(de)(de)最(zui)上層。莫里(li)遜組被(bei)認為是(shi)半干旱的(de)(de)環境,具(ju)有明顯的(de)(de)雨季和旱季,地(di)(di)(di)形為平坦的(de)(de)泛濫平原。該地(di)(di)(di)層的(de)(de)植(zhi)被(bei)是(shi)由(you)針葉樹、樹蕨、蕨類(lei)所構成(cheng)的(de)(de)樹林,以(yi)及由(you)蕨類(lei)所構成(cheng)的(de)(de)疏林莽原。
莫(mo)(mo)里(li)遜組是個富含化(hua)(hua)石(shi)的(de)(de)(de)挖掘地(di)點,該地(di)曾(ceng)發現(xian)綠藻、真(zhen)菌、苔蘚、木賊、蕨類、蘇鐵、銀(yin)杏、以及(ji)數科針葉樹等植物化(hua)(hua)石(shi);其他的(de)(de)(de)動物化(hua)(hua)石(shi)則包(bao)含:雙殼(ke)綱、蝸牛、輻鰭魚綱、青(qing)蛙、蠑螈、烏龜、喙頭目(mu)(mu)、蜥(xi)蜴、陸生(sheng)(sheng)與(yu)水(shui)生(sheng)(sheng)的(de)(de)(de)鱷形超目(mu)(mu)、數種翼龍(long)目(mu)(mu)、大量(liang)的(de)(de)(de)恐龍(long)、以及(ji)早期的(de)(de)(de)哺乳類,例如:柱齒(chi)(chi)獸目(mu)(mu)、多瘤齒(chi)(chi)目(mu)(mu)、對齒(chi)(chi)獸目(mu)(mu)、三(san)尖齒(chi)(chi)獸目(mu)(mu)。莫(mo)(mo)里(li)遜組所發現(xian)的(de)(de)(de)恐龍(long)則包(bao)含了獸腳亞目(mu)(mu)的(de)(de)(de)角鼻(bi)龍(long)、嗜鳥龍(long)、蠻龍(long),蜥(xi)腳下目(mu)(mu)的(de)(de)(de)迷惑龍(long)、腕龍(long)、圓(yuan)頂龍(long)、梁龍(long),鳥臀目(mu)(mu)的(de)(de)(de)彎(wan)龍(long)、橡樹龍(long)、劍龍(long)。
在(zai)(zai)猶他州(zhou)的(de)克(ke)利(li)夫蘭(lan)(lan)勞埃(ai)德(de)采石(shi)(shi)場(chang),有一個(ge)數量眾多(duo)的(de)化石(shi)(shi)層。這個(ge)化石(shi)(shi)層包含超(chao)過10,000個(ge)骨頭,大(da)部分屬于(yu)(yu)(yu)異特(te)(te)龍(long)(long)(long)化石(shi)(shi),但(dan)也(ye)(ye)有其他恐(kong)(kong)龍(long)(long)(long)化石(shi)(shi),例(li)如(ru)劍龍(long)(long)(long)與角鼻(bi)龍(long)(long)(long)。如(ru)此(ci)眾多(duo)的(de)動物化石(shi)(shi)為(wei)何集(ji)中(zhong)于(yu)(yu)(yu)同一地點,仍不清楚。而且肉食(shi)性恐(kong)(kong)龍(long)(long)(long)的(de)比例(li)大(da)于(yu)(yu)(yu)草食(shi)性恐(kong)(kong)龍(long)(long)(long),這種狀況非常的(de)少見。這個(ge)化石(shi)(shi)層被解釋成群體獵食(shi)所造成的(de),但(dan)很難證(zheng)實(shi)。另一個(ge)可能性是克(ke)利(li)夫蘭(lan)(lan)勞埃(ai)德(de)恐(kong)(kong)龍(long)(long)(long)采石(shi)(shi)場(chang)在(zai)(zai)過去是個(ge)"掠食(shi)者陷(xian)阱",類(lei)似拉布(bu)雷亞瀝青坑,造成大(da)量的(de)掠食(shi)者陷(xian)入無法掙(zheng)脫(tuo)的(de)沉(chen)積層中(zhong)。葡萄(tao)(tao)牙(ya)所發現異特(te)(te)龍(long)(long)(long)的(de)地層,年代(dai)屬于(yu)(yu)(yu)晚侏羅(luo)紀(ji),被認為(wei)環境類(lei)似莫(mo)里遜組(zu),但(dan)受到(dao)海洋的(de)影響較多(duo)。這個(ge)葡萄(tao)(tao)牙(ya)地層也(ye)(ye)發現了許多(duo)莫(mo)里遜組(zu)的(de)恐(kong)(kong)龍(long)(long)(long),主要有異特(te)(te)龍(long)(long)(long)、角鼻(bi)龍(long)(long)(long)、蠻龍(long)(long)(long)、迷惑龍(long)(long)(long),或者是相近(jin)物種,例(li)如(ru)腕(wan)龍(long)(long)(long)的(de)近(jin)親葡萄(tao)(tao)牙(ya)巨(ju)龍(long)(long)(long)、彎龍(long)(long)(long)的(de)近(jin)親龍(long)(long)(long)爪龍(long)(long)(long)。
異(yi)(yi)(yi)特龍(long)(long)(long)與(yu)其他侏羅(luo)紀獸(shou)腳類(lei)(lei)(lei)恐(kong)(kong)龍(long)(long)(long)共同生(sheng)存在(zai)莫里遜組與(yu)葡萄牙(ya),包(bao)含(han):角(jiao)鼻龍(long)(long)(long)、體型較(jiao)(jiao)大(da)的(de)(de)(de)蠻(man)龍(long)(long)(long),食蜥王龍(long)(long)(long),依潘龍(long)(long)(long)。這(zhe)點很不尋常。根(gen)據(ju)生(sheng)理結(jie)構(gou)與(yu)化石(shi)位置(zhi),它(ta)們(men)三(san)者(zhe)似乎擁有(you)(you)(you)不同的(de)(de)(de)生(sheng)態位。角(jiao)鼻龍(long)(long)(long)與(yu)蠻(man)龍(long)(long)(long)可(ke)(ke)能(neng)活(huo)躍(yue)于河道附近,角(jiao)鼻龍(long)(long)(long)身(shen)體較(jiao)(jiao)細,叫矮,而蠻(man)龍(long)(long)(long)則十分粗壯,擁有(you)(you)(you)威力巨大(da)的(de)(de)(de)爪子和(he)威力無窮的(de)(de)(de)放血(xue)牙(ya)加(jia)碎骨牙(ya),但體型至少有(you)(you)(you)10-12米(mi)+,可(ke)(ke)使它(ta)們(men)躲藏(zang)在(zai)森(sen)林(lin)中突襲迷惑龍(long)(long)(long),腕龍(long)(long)(long)這(zhe)類(lei)(lei)(lei)大(da)型蜥腳類(lei)(lei)(lei),有(you)(you)(you)時也會去捕(bu)獵劍龍(long)(long)(long)家族的(de)(de)(de)成員(yuan);異(yi)(yi)(yi)特龍(long)(long)(long)的(de)(de)(de)腿部較(jiao)(jiao)長、速(su)度較(jiao)(jiao)快,但它(ta)們(men)在(zai)森(sen)林(lin)或(huo)矮樹叢(cong)中較(jiao)(jiao)不靈(ling)活(huo),因(yin)此可(ke)(ke)能(neng)活(huo)躍(yue)于干燥的(de)(de)(de)泛濫平原中。對于角(jiao)鼻龍(long)(long)(long)的(de)(de)(de)研(yan)究(jiu)比蠻(man)龍(long)(long)(long)還深入。角(jiao)鼻龍(long)(long)(long)與(yu)異(yi)(yi)(yi)特龍(long)(long)(long)的(de)(de)(de)差別在(zai)于,它(ta)們(men)的(de)(de)(de)頭顱骨較(jiao)(jiao)高、較(jiao)(jiao)狹窄,而牙(ya)齒(chi)較(jiao)(jiao)大(da)、較(jiao)(jiao)寬廣。在(zai)一(yi)(yi)個(ge)(ge)異(yi)(yi)(yi)特龍(long)(long)(long)的(de)(de)(de)恥骨末端發現了另一(yi)(yi)個(ge)(ge)獸(shou)腳類(lei)(lei)(lei)恐(kong)(kong)龍(long)(long)(long)的(de)(de)(de)齒(chi)痕(hen),可(ke)(ke)能(neng)是(shi)(shi)由角(jiao)鼻龍(long)(long)(long)或(huo)蠻(man)龍(long)(long)(long)所留下的(de)(de)(de),異(yi)(yi)(yi)特龍(long)(long)(long)可(ke)(ke)能(neng)也是(shi)(shi)其他獸(shou)腳類(lei)(lei)(lei)恐(kong)(kong)龍(long)(long)(long)的(de)(de)(de)食物來源(yuan)選(xuan)擇(ze)之(zhi)一(yi)(yi),但是(shi)(shi)恥骨是(shi)(shi)位于腹部下緣,夾在(zai)兩腿之(zhi)間,處于身(shen)體最龐大(da)的(de)(de)(de)地方之(zhi)一(yi)(yi)。顯示這(zhe)只異(yi)(yi)(yi)特龍(long)(long)(long)是(shi)(shi)在(zai)死后(hou),尸體被(bei)其他恐(kong)(kong)龍(long)(long)(long)所吞食。
在大(da)眾文化(hua)中,異(yi)特(te)龍(long)(long)(long)(long)與暴龍(long)(long)(long)(long)皆是(shi)大(da)型肉(rou)食性恐(kong)龍(long)(long)(long)(long)的(de)(de)代表。異(yi)特(te)龍(long)(long)(long)(long)也是(shi)博物館常見(jian)的(de)(de)恐(kong)龍(long)(long)(long)(long)之一,部分原因為(wei)克利(li)夫蘭勞埃德(de)恐(kong)龍(long)(long)(long)(long)采石(shi)(shi)場所出土的(de)(de)大(da)量異(yi)特(te)龍(long)(long)(long)(long)化(hua)石(shi)(shi);到了1976年,已經有(you)三大(da)洲(zhou)、八個(ge)國(guo)家(jia)的(de)(de)38個(ge)博物館具有(you)從克利(li)夫蘭勞埃德(de)恐(kong)龍(long)(long)(long)(long)采石(shi)(shi)場所出土的(de)(de)異(yi)特(te)龍(long)(long)(long)(long)化(hua)石(shi)(shi)。異(yi)特(te)龍(long)(long)(long)(long)是(shi)猶他(ta)州(zhou)的(de)(de)官方州(zhou)恐(kong)龍(long)(long)(long)(long)。
自20世紀初期開始,異(yi)特(te)(te)龍便已(yi)出現在大眾(zhong)文化之中。在BBC(迷失的世界)中就出現過異(yi)特(te)(te)龍的身影并襲(xi)擊了主(zhu)角和原始人,另外本片中有三只(zhi)異(yi)特(te)(te)龍。
異(yi)特(te)龍還短暫的出(chu)現在(zai)2009年(nian)的電影(ying)《失落的大陸》在(zai)影(ying)片中與霸(ba)王(wang)龍展(zhan)開了對決但(dan)(dan)之(zhi)后(hou)又和霸(ba)王(wang)龍一起(qi)襲擊(ji)了主角和他的朋友,但(dan)(dan)在(zai)影(ying)片的最后(hou)被主角的杯子炸死(si)。
異特(te)龍(long)也出現在BBC的(de)(de)(de)電(dian)視節(jie)目(mu)《與(yu)恐龍(long)共舞》(Walking with Dinosaurs)的(de)(de)(de)第(di)(di)二(er)集與(yu)第(di)(di)五集。而《與(yu)恐龍(long)共舞》的(de)(de)(de)特(te)別(bie)節(jie)目(mu)《異特(te)龍(long)之謎》(Ballad of Big Al),則(ze)是以著名的(de)(de)(de)"大艾(ai)爾(er)"作(zuo)為主角,敘(xu)述了它的(de)(de)(de)一生。
異特龍也出現(xian)在《恐(kong)龍x檔案》中。
另有紀錄片(pian)《恐龍(long)(long)革命》第(di)一季的(de)第(di)二集《異特(te)龍(long)(long)的(de)故事》講述一只下(xia)顎被打(da)斷的(de)異特(te)龍(long)(long)的(de)生活。
在CAPCOM于(yu)2000年推出的(de)電子游戲《恐龍(long)危機2》中,異特(te)龍(long)也(ye)有多次登場。
異(yi)特(te)龍(long)也出現在(zai)IOS的游戲(侏羅紀世(shi)界)中被錯誤的描述成有2個爪子類(lei)似霸(ba)王龍(long)實際上真實的異(yi)特(te)龍(long)是有三個爪子,不(bu)要被游戲欺(qi)騙了。