異(yi)特(te)龍(long),又名躍龍(long)或(huo)異(yi)龍(long),是蜥臀(tun)目獸腳亞目肉食(shi)龍(long)下目恐龍(long)的(de)一屬。異(yi)特(te)龍(long)是種中(zhong)型的(de)二足、掠食(shi)性恐龍(long),身長8.5米,最大9.7米,體重1.5~3噸最重3.6噸。它們(men)生存于(yu)晚侏羅紀,約(yue)1億(yi)5500萬(wan)年(nian)前到1億(yi)3500萬(wan)年(nian)前。自從在1877年(nian)被(bei)奧塞(sai)內爾·查(cha)利斯·馬什(Othniel Charles Marsh)命名以來,已有許多(duo)的(de)可能種被(bei)歸類(lei)于(yu)異(yi)特(te)龍(long)屬,但只有少數被(bei)認為(wei)是有效種。
異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)屬于異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科,異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科是(shi)(shi)(shi)(shi)一個大(da)(da)型(xing)獸(shou)(shou)(shou)腳(jiao)亞(ya)目的(de)(de)(de)(de)演(yan)化支。奧(ao)塞內爾·查利斯(si)·馬(ma)什在(zai)1878年建立(li)異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科;但在(zai)70年代(dai)以(yi)前,異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科很少被(bei)(bei)使(shi)(shi)(shi)用(yong)(yong),取(qu)而(er)代(dai)之的(de)(de)(de)(de)是(shi)(shi)(shi)(shi)斑龍(long)(long)(long)(long)(long)(long)科,但斑龍(long)(long)(long)(long)(long)(long)科長期以(yi)來(lai)被(bei)(bei)當作大(da)(da)型(xing)獸(shou)(shou)(shou)腳(jiao)類(lei)恐龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)(de)"未(wei)歸類(lei)物種(zhong)集中(zhong)(zhong)地"。在(zai)1976年麥迪遜(xun)公布他(ta)(ta)的(de)(de)(de)(de)專題(ti)論文(wen)(wen)以(yi)前,跟異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)相(xiang)同時期被(bei)(bei)命名(ming)的(de)(de)(de)(de)腔軀龍(long)(long)(long)(long)(long)(long),常(chang)被(bei)(bei)當作異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)(de)同義詞,而(er)且(qie)更常(chang)被(bei)(bei)使(shi)(shi)(shi)用(yong)(yong)。數(shu)個研(yan)究人員曾在(zai)他(ta)(ta)們的(de)(de)(de)(de)著(zhu)作中(zhong)(zhong)使(shi)(shi)(shi)用(yong)(yong)斑龍(long)(long)(long)(long)(long)(long)科來(lai)取(qu)代(dai)異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科,包含(han):吉(ji)爾摩爾、休尼(ni)博士、羅默博士、羅德尼(ni)·史提爾、以(yi)及亞(ya)歷克·沃克。在(zai)麥迪遜(xun)公布他(ta)(ta)的(de)(de)(de)(de)具影響力專題(ti)論文(wen)(wen)之后(hou),異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科開始普遍使(shi)(shi)(shi)用(yong)(yong),但沒(mei)有(you)(you)被(bei)(bei)明確的(de)(de)(de)(de)定(ding)義。一些半(ban)科學(xue)性質(zhi)的(de)(de)(de)(de)著(zhu)作將異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科使(shi)(shi)(shi)用(yong)(yong)于不同的(de)(de)(de)(de)大(da)(da)型(xing)獸(shou)(shou)(shou)腳(jiao)類(lei)恐龍(long)(long)(long)(long)(long)(long),通常(chang)包含(han)那些比斑龍(long)(long)(long)(long)(long)(long)科更大(da)(da)型(xing)、更著(zhu)名(ming)的(de)(de)(de)(de)物種(zhong)。在(zai)獸(shou)(shou)(shou)腳(jiao)亞(ya)目中(zhong)(zhong),常(chang)被(bei)(bei)認為(wei)是(shi)(shi)(shi)(shi)異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)近親(qin)的(de)(de)(de)(de)物種(zhong),包含(han):印度龍(long)(long)(long)(long)(long)(long)、皮亞(ya)尼(ni)茲基龍(long)(long)(long)(long)(long)(long)、皮爾逖龍(long)(long)(long)(long)(long)(long)、永(yong)川(chuan)龍(long)(long)(long)(long)(long)(long)、高(gao)棘龍(long)(long)(long)(long)(long)(long)、吉(ji)蘭(lan)泰龍(long)(long)(long)(long)(long)(long)、巧(qiao)鱷龍(long)(long)(long)(long)(long)(long)、史托龍(long)(long)(long)(long)(long)(long)、以(yi)及四川(chuan)龍(long)(long)(long)(long)(long)(long)。隨者(zhe)相(xiang)關恐龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)(de)研(yan)究增加(jia),獸(shou)(shou)(shou)腳(jiao)類(lei)恐龍(long)(long)(long)(long)(long)(long)開始變得多(duo)樣性。而(er)親(qin)緣分支分類(lei)法研(yan)究則(ze)顯示,上(shang)述原本被(bei)(bei)認為(wei)是(shi)(shi)(shi)(shi)異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)近親(qin)的(de)(de)(de)(de)物種(zhong),都(dou)不是(shi)(shi)(shi)(shi)異(yi)(yi)(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)科的(de)(de)(de)(de)成員,只有(you)(you)少數(shu)屬被(bei)(bei)歸類(lei)于相(xiang)近的(de)(de)(de)(de)科,例如:高(gao)棘龍(long)(long)(long)(long)(long)(long)、永(yong)川(chuan)龍(long)(long)(long)(long)(long)(long)。
異(yi)(yi)特(te)(te)龍(long)(long)(long)科(ke)(ke)(ke)是(shi)(shi)(shi)肉食(shi)(shi)龍(long)(long)(long)下目的三個科(ke)(ke)(ke)之一(yi)(yi),其他兩(liang)個分別為鯊齒龍(long)(long)(long)科(ke)(ke)(ke)與中華(hua)盜龍(long)(long)(long)科(ke)(ke)(ke)。在1988年,葛(ge)瑞格(ge)利(li)·保(bao)羅提出異(yi)(yi)特(te)(te)龍(long)(long)(long)科(ke)(ke)(ke)演(yan)化為暴龍(long)(long)(long)科(ke)(ke)(ke),因(yin)此成為并系(xi)群;但(dan)(dan)這個看法(fa)已(yi)遭(zao)到否定,暴龍(long)(long)(long)科(ke)(ke)(ke)已(yi)經(jing)被歸(gui)類(lei)為另(ling)一(yi)(yi)群獸腳類(lei)支(zhi)系(xi),虛骨(gu)龍(long)(long)(long)類(lei)。異(yi)(yi)特(te)(te)龍(long)(long)(long)科(ke)(ke)(ke)是(shi)(shi)(shi)肉食(shi)(shi)龍(long)(long)(long)下目中成員(yuan)最少的一(yi)(yi)科(ke)(ke)(ke),在大多數的研究中,除了(le)異(yi)(yi)特(te)(te)龍(long)(long)(long)屬以外,只有(you)食(shi)(shi)蜥王龍(long)(long)(long)以及一(yi)(yi)個發現(xian)于法(fa)國的未命名(ming)異(yi)(yi)特(te)(te)龍(long)(long)(long)超科(ke)(ke)(ke)恐龍(long)(long)(long)被認為是(shi)(shi)(shi)可能的有(you)效屬。Epanterias是(shi)(shi)(shi)另(ling)一(yi)(yi)個可能的有(you)效屬,但(dan)(dan)Epanterias與食(shi)(shi)蜥王龍(long)(long)(long)有(you)可能是(shi)(shi)(shi)異(yi)(yi)特(te)(te)龍(long)(long)(long)屬的大型(xing)個體。最近的研究則保(bao)留(liu)了(le)食(shi)(shi)蜥王龍(long)(long)(long),而(er)將Epanterias歸(gui)類(lei)于異(yi)(yi)特(te)(te)龍(long)(long)(long)的一(yi)(yi)個種(zhong)。
尚不清(qing)楚異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)屬究竟有(you)多(duo)(duo)(duo)少個(ge)種(zhong)(zhong)(zhong)(zhong)(zhong)類(lei)(lei)(lei)(lei)。自從1988年(nian)(nian)以(yi)(yi)(yi)來(lai),已有(you)七(qi)個(ge)種(zhong)(zhong)(zhong)(zhong)(zhong)被(bei)(bei)視(shi)為(wei)(wei)(wei)是(shi)可(ke)能的(de)(de)(de)(de)(de)有(you)效(xiao)(xiao)種(zhong)(zhong)(zhong)(zhong)(zhong)。例(li)如:模式(shi)種(zhong)(zhong)(zhong)(zhong)(zhong)脆(cui)弱(ruo)(ruo)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)(A. fragilis)、合異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)(A. amplexus)、歐洲異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)(A. europaeus)、尚未(wei)(wei)有(you)正式(shi)敘述的(de)(de)(de)(de)(de)詹氏(shi)(shi)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)(A. jimmadseni)、坦(tan)(tan)達(da)(da)格(ge)(ge)魯(lu)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)(A. tendagurensis),但其(qi)中只有(you)少數(shu)種(zhong)(zhong)(zhong)(zhong)(zhong)普遍(bian)被(bei)(bei)視(shi)為(wei)(wei)(wei)有(you)效(xiao)(xiao)的(de)(de)(de)(de)(de)種(zhong)(zhong)(zhong)(zhong)(zhong)。此外,還(huan)有(you)至少10個(ge)可(ke)疑名稱或未(wei)(wei)敘述的(de)(de)(de)(de)(de)種(zhong)(zhong)(zhong)(zhong)(zhong)曾被(bei)(bei)歸類(lei)(lei)(lei)(lei)于(yu)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)屬。在(zai)基(ji)礎堅尾龍(long)(long)(long)(long)類(lei)(lei)(lei)(lei)獸(shou)腳(jiao)類(lei)(lei)(lei)(lei)恐龍(long)(long)(long)(long)的(de)(de)(de)(de)(de)研究中,只有(you)脆(cui)弱(ruo)(ruo)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)、詹氏(shi)(shi)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)(被(bei)(bei)列為(wei)(wei)(wei)未(wei)(wei)命名種(zhong)(zhong)(zhong)(zhong)(zhong))、以(yi)(yi)(yi)及(ji)坦(tan)(tan)達(da)(da)格(ge)(ge)魯(lu)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)被(bei)(bei)承認是(shi)可(ke)能的(de)(de)(de)(de)(de)有(you)效(xiao)(xiao)種(zhong)(zhong)(zhong)(zhong)(zhong);而(er)合異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)(即(ji)為(wei)(wei)(wei)Epanterias)、殘暴異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)被(bei)(bei)視(shi)為(wei)(wei)(wei)是(shi)脆(cui)弱(ruo)(ruo)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)的(de)(de)(de)(de)(de)異(yi)(yi)(yi)(yi)(yi)名,歐洲異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)并沒被(bei)(bei)承認,巨(ju)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)曾被(bei)(bei)建立為(wei)(wei)(wei)食蜥王龍(long)(long)(long)(long)。合異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)、脆(cui)弱(ruo)(ruo)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)、詹氏(shi)(shi)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)、巨(ju)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)的(de)(de)(de)(de)(de)化(hua)石都來(lai)自于(yu)莫(mo)(mo)里遜組,莫(mo)(mo)里遜組散布于(yu)美國的(de)(de)(de)(de)(de)科羅(luo)拉(la)多(duo)(duo)(duo)州(zhou)(zhou)、蒙大(da)拿州(zhou)(zhou)、新(xin)墨西哥州(zhou)(zhou)、奧克拉(la)荷馬州(zhou)(zhou)、南達(da)(da)科他(ta)州(zhou)(zhou)、猶他(ta)州(zhou)(zhou)、以(yi)(yi)(yi)及(ji)懷俄明州(zhou)(zhou),年(nian)(nian)代為(wei)(wei)(wei)上侏羅(luo)紀(ji)的(de)(de)(de)(de)(de)啟(qi)莫(mo)(mo)里階到(dao)提通階。在(zai)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)中,詹氏(shi)(shi)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)化(hua)石標本最大(da)。脆(cui)弱(ruo)(ruo)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)是(shi)該地層最常(chang)發(fa)現、最著名的(de)(de)(de)(de)(de)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)化(hua)石,已發(fa)現至少60個(ge)個(ge)體的(de)(de)(de)(de)(de)化(hua)石。自從80年(nian)(nian)代以(yi)(yi)(yi)來(lai),有(you)爭論懷疑莫(mo)(mo)里遜組是(shi)否存在(zai)者另一(yi)種(zhong)(zhong)(zhong)(zhong)(zhong)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long),殘暴異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long):研究仍(reng)維(wei)持莫(mo)(mo)里遜組只有(you)脆(cui)弱(ruo)(ruo)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)的(de)(de)(de)(de)(de)看法,而(er)該地層所(suo)發(fa)現的(de)(de)(de)(de)(de)不同(tong)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)化(hua)石間(jian)的(de)(de)(de)(de)(de)差異(yi)(yi)(yi)(yi)(yi),被(bei)(bei)認為(wei)(wei)(wei)是(shi)不同(tong)個(ge)體間(jian)的(de)(de)(de)(de)(de)變化(hua)。歐洲異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)的(de)(de)(de)(de)(de)化(hua)石發(fa)現于(yu)葡萄牙勞爾哈組的(de)(de)(de)(de)(de)波多(duo)(duo)(duo)諾伏,體長只有(you)9米(mi)2噸,年(nian)(nian)代為(wei)(wei)(wei)啟(qi)莫(mo)(mo)里階,可(ke)能與脆(cui)弱(ruo)(ruo)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)是(shi)同(tong)一(yi)種(zhong)(zhong)(zhong)(zhong)(zhong)動物。坦(tan)(tan)達(da)(da)格(ge)(ge)魯(lu)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)被(bei)(bei)發(fa)現于(yu)坦(tan)(tan)尚尼亞(ya)姆特(te)(te)(te)瓦拉(la)區的(de)(de)(de)(de)(de)坦(tan)(tan)達(da)(da)格(ge)(ge)魯(lu),年(nian)(nian)代也為(wei)(wei)(wei)啟(qi)莫(mo)(mo)里階。大(da)部分(fen)的(de)(de)(de)(de)(de)研究把坦(tan)(tan)達(da)(da)格(ge)(ge)魯(lu)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)視(shi)為(wei)(wei)(wei)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)的(de)(de)(de)(de)(de)有(you)效(xiao)(xiao)種(zhong)(zhong)(zhong)(zhong)(zhong),但它(ta)有(you)可(ke)能是(shi)一(yi)種(zhong)(zhong)(zhong)(zhong)(zhong)基(ji)礎堅尾龍(long)(long)(long)(long)類(lei)(lei)(lei)(lei),或僅是(shi)獸(shou)腳(jiao)亞(ya)目的(de)(de)(de)(de)(de)一(yi)個(ge)疑名。雖然歸類(lei)(lei)(lei)(lei)仍(reng)不確定,坦(tan)(tan)達(da)(da)格(ge)(ge)魯(lu)異(yi)(yi)(yi)(yi)(yi)特(te)(te)(te)龍(long)(long)(long)(long)是(shi)種(zhong)(zhong)(zhong)(zhong)(zhong)大(da)型獸(shou)腳(jiao)類(lei)(lei)(lei)(lei)恐龍(long)(long)(long)(long),身長可(ke)能約(yue)9公尺,體重約(yue)有(you)2.5公噸。
異特(te)(te)龍(long)(long)的(de)可能異名(ming)有腔軀龍(long)(long)、Creosaurus、Epanterias、以及Labrosaurus。而異特(te)(te)龍(long)(long)大(da)部分的(de)種是根(gen)據零碎的(de)化石來命(ming)名(ming),許多(duo)被認為是破碎異特(te)(te)龍(long)(long)的(de)異名(ming),或者是被錯誤(wu)歸類到異特(te)(te)龍(long)(long)屬。其中一個(ge)例子是Labrosaurus ferox,是由馬(ma)什(shen)在1884年所命(ming)名(ming),但(dan)他是根(gen)據一個(ge)外(wai)形(xing)(xing)奇怪的(de)部分下(xia)顎(e),而顎(e)部前(qian)端的(de)齒列有個(ge)明(ming)顯的(de)缺口,顎(e)部后段則延展(zhan)并外(wai)翻。后來的(de)研究人員(yuan)提(ti)出這(zhe)(zhe)個(ge)下(xia)顎(e)骨頭具有病狀,應該(gai)是該(gai)動物生(sheng)前(qian)受(shou)傷的(de)痕跡,而后段變形(xing)(xing)的(de)部分原(yuan)因(yin)為石膏重建的(de)后果。這(zhe)(zhe)個(ge)化石現被認為屬于脆弱異特(te)(te)龍(long)(long)。被認為屬于異特(te)(te)龍(long)(long)的(de)化石散布于全世界,包含(han)澳洲、西伯(bo)利亞、以及瑞(rui)士,但(dan)這(zhe)(zhe)些化石被認為其他的(de)恐(kong)龍(long)(long)。
異(yi)特(te)龍(long)(long)(long)是(shi)該(gai)時期北美洲莫里遜組最常見的(de)大(da)型掠(lve)食(shi)者(zhe),并位(wei)在(zai)食(shi)物(wu)鏈(lian)的(de)頂(ding)層。它們(men)可能以(yi)其他大(da)型草食(shi)性恐龍(long)(long)(long)為食(shi),例如:鳥腳(jiao)目(mu)、蜥腳(jiao)下目(mu)恐龍(long)(long)(long)。異(yi)特(te)龍(long)(long)(long)經常被認為采(cai)用群(qun)體合作方式攻(gong)(gong)擊(ji)蜥腳(jiao)類恐龍(long)(long)(long),但很少證據顯示(shi)異(yi)特(te)龍(long)(long)(long)具有共同攻(gong)(gong)擊(ji)的(de)社會行為。它們(men)可能采(cai)取伏擊(ji)方式攻(gong)(gong)擊(ji)大(da)型獵物(wu),使用上顎來撞擊(ji)獵物(wu)。
異(yi)(yi)特(te)龍(long)(long)(Allosaurus)又(you)稱躍龍(long)(long)或異(yi)(yi)龍(long)(long),是蜥(xi)臀(tun)目(mu)獸腳亞目(mu)恐(kong)龍(long)(long)的一屬。異(yi)(yi)特(te)龍(long)(long)是種中型(xing)的二足(zu)、掠(lve)食(shi)性恐(kong)龍(long)(long),身長為9米,最大可達(da)9.7米。它們(men)生(sheng)存于晚侏(zhu)羅紀,約1億5500萬(wan)年~1億3500萬(wan)年前。
這是一種大家熟知的恐龍(long)。它(ta)已經成(cheng)為定(ding)義侏羅紀的食(shi)肉(rou)(rou)者,以及食(shi)肉(rou)(rou)恐龍(long)--大型獸腳(jiao)類恐龍(long)的典范。
異特龍具有(you)(you)(you)大(da)(da)型的(de)(de)(de)(de)頭(tou)(tou)顱骨(gu),上(shang)有(you)(you)(you)大(da)(da)型洞孔,可減輕(qing)重(zhong)量,眼(yan)睛上(shang)方擁有(you)(you)(you)角冠。它(ta)(ta)(ta)們的(de)(de)(de)(de)頭(tou)(tou)顱骨(gu)是由幾個分開(kai)的(de)(de)(de)(de)骨(gu)頭(tou)(tou)組成的(de)(de)(de)(de),骨(gu)頭(tou)(tou)之間有(you)(you)(you)可活動(dong)(dong)關節,進食時(shi)頜(he)部(bu)可先下上(shang)張(zhang)開(kai),然后(hou)在(zai)左右撐開(kai)吞下食物;它(ta)(ta)(ta)們的(de)(de)(de)(de)下頜(he)也可以前后(hou)滑動(dong)(dong)。嘴部(bu)擁有(you)(you)(you)70顆大(da)(da)型、銳利、彎曲(qu)的(de)(de)(de)(de)牙齒。相較于大(da)(da)型、強壯(zhuang)的(de)(de)(de)(de)后(hou)肢,它(ta)(ta)(ta)們的(de)(de)(de)(de)前肢小(xiao),手部(bu)有(you)(you)(you)三指,指爪(zhua)大(da)(da)而彎曲(qu),長度為25厘米。尾巴長而重(zhong),可平衡身(shen)體與(yu)頭(tou)(tou)部(bu)。異特龍的(de)(de)(de)(de)骨(gu)架和其它(ta)(ta)(ta)獸腳亞目恐龍一般,呈現出類似鳥類的(de)(de)(de)(de)輕(qing)巧中空特征。
異特(te)龍(long)是該時期北美洲莫里(li)遜組最(zui)常見(jian)的(de)大(da)型掠(lve)食(shi)(shi)動物,并位(wei)在食(shi)(shi)物鏈(lian)的(de)頂(ding)層。它(ta)們可能以其(qi)他大(da)型草食(shi)(shi)性(xing)恐(kong)龍(long)為食(shi)(shi),例(li)如:鳥腳下目(mu)、劍龍(long)科、蜥腳下目(mu)恐(kong)龍(long)。異特(te)龍(long)常被(bei)認為采(cai)用(yong)群體(ti)合作(zuo)方式(shi)攻擊蜥腳類恐(kong)龍(long),但很少(shao)有證據(ju)顯示異特(te)龍(long)具有共同攻擊的(de)社會(hui)行為。它(ta)們有可能采(cai)取(qu)伏擊方式(shi)攻擊大(da)型獵物,使用(yong)上頜來撞擊獵物。
第(di)一(yi)個可(ke)明確歸類(lei)于(yu)異特(te)龍(long)(long)的化(hua)石(shi),是在1877年由(you)奧塞內(nei)爾·查利(li)斯(si)·馬什(Othniel Charles Marsh)所發現。異特(te)龍(long)(long)具有(you)(you)復雜的分類(lei)歷史,過去曾有(you)(you)許(xu)多種最初被歸類(lei)于(yu)異特(te)龍(long)(long),腔軀龍(long)(long),直到在克(ke)利(li)夫蘭勞(lao)埃德采(cai)石(shi)場發現大(da)量的化(hua)石(shi)后,異特(te)龍(long)(long)才成(cheng)為常(chang)用的名(ming)稱,并成(cheng)為最廣受研(yan)究(jiu)的恐龍(long)(long)之一(yi)。
異特(te)龍的(de)(de)化石主要來自于北(bei)美洲的(de)(de)莫里遜組(zu),另(ling)外在葡萄牙、坦桑尼亞也發現了(le)可能的(de)(de)化石。異特(te)龍的(de)(de)化石是美國猶他(ta)州(zhou)的(de)(de)州(zhou)化石。由于異特(te)龍是最早(zao)被發現的(de)(de)獸腳亞目恐(kong)龍之一,所以長期以來吸(xi)引了(le)一般大眾的(de)(de)注意(yi),并出現在數個電影與電視節目中。
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(dun)。在1976年,詹姆斯(si)·麥(mai)迪(di)遜(James Madsen)的異(yi)特龍(long)(long)專題論(lun)文中(zhong),他提出異(yi)特龍(long)(long)的身長最大值為13米(mi)。如同(tong)其他的恐龍(long)(long),異(yi)特龍(long)(long)的體(ti)重估(gu)計值也有(you)爭議,自(zi)20世紀80年代以來,成年異(yi)特龍(long)(long)的體(ti)重估(gu)計值,已有(you)1000公(gong)斤,以及1010公(gong)斤等不同(tong)的數據(ju)。
莫(mo)(mo)里(li)(li)遜組(zu)專家(jia)約翰·福斯特(te)(te)(te)(John Foster)提出,大(da)型的成年(nian)脆弱異(yi)(yi)特(te)(te)(te)龍(long)(long)的體重為(wei)1000公斤,但根據他(ta)所測量、參(can)考(kao)的股骨(gu),合(he)理的估計值應約750~800公斤。有數個巨型標(biao)本被(bei)歸(gui)類于(yu)(yu)異(yi)(yi)特(te)(te)(te)龍(long)(long)屬(shu),但可能事實上(shang)屬(shu)于(yu)(yu)其他(ta)恐(kong)龍(long)(long)。異(yi)(yi)特(te)(te)(te)龍(long)(long)的近親食蜥王龍(long)(long)(編(bian)號OMNH 1708)身(shen)長可能有13米。曾被(bei)歸(gui)類于(yu)(yu)異(yi)(yi)特(te)(te)(te)龍(long)(long)的一(yi)種,巨異(yi)(yi)特(te)(te)(te)龍(long)(long)(A. maximus),最近的研究(jiu)多認為(wei)它(ta)們是(shi)個別的屬(shu)。另一(yi)個可能屬(shu)于(yu)(yu)異(yi)(yi)特(te)(te)(te)龍(long)(long)的標(biao)本(編(bian)號AMNH 5768),曾長期被(bei)歸(gui)類于(yu)(yu)Epanterias,身(shen)長為(wei)12.1公尺。在(zai)新(xin)墨(mo)西哥州莫(mo)(mo)里(li)(li)遜組(zu)的彼得森采石場,發現一(yi)個大(da)型的異(yi)(yi)特(te)(te)(te)龍(long)(long)科部分骨(gu)骼,是(shi)食蜥王龍(long)(long)的第二個標(biao)本。
在獸腳亞(ya)目之中,異(yi)(yi)特(te)(te)龍(long)(long)的(de)(de)頭顱(lu)骨(gu)、牙齒(chi)(chi)與身體的(de)(de)比例適中。葛瑞格利(li)·保羅(luo)(Gregory S. Paul)依據一個(ge)長度為(wei)84.5公分(fen)的(de)(de)異(yi)(yi)特(te)(te)龍(long)(long)頭顱(lu)骨(gu),估計該個(ge)體的(de)(de)身長為(wei)7.9米。每(mei)(mei)塊前上顎(e)骨(gu)各有(you)(you)5顆(ke)牙齒(chi)(chi),牙齒(chi)(chi)的(de)(de)橫剖面呈D形,而(er)(er)每(mei)(mei)塊上顎(e)骨(gu)約(yue)有(you)(you)14到17顆(ke)牙齒(chi)(chi);異(yi)(yi)特(te)(te)龍(long)(long)的(de)(de)牙齒(chi)(chi)數量與骨(gu)頭大小并(bing)不呈正比。而(er)(er)每(mei)(mei)塊齒(chi)(chi)骨(gu)約(yue)有(you)(you)14到17顆(ke)牙齒(chi)(chi),平均數量為(wei)16顆(ke)。越往嘴部(bu)深處(chu),牙齒(chi)(chi)就(jiu)越短、狹窄、彎曲。異(yi)(yi)特(te)(te)龍(long)(long)的(de)(de)牙齒(chi)(chi)都為(wei)鋸齒(chi)(chi)狀。這些(xie)牙齒(chi)(chi)很容易脫(tuo)落(luo),所以它們會(hui)不斷地生(sheng)長、替代,并(bing)成(cheng)為(wei)常發現的(de)(de)化(hua)石。霸王龍(long)(long)嘴里有(you)(you)60顆(ke)牙齒(chi)(chi),異(yi)(yi)特(te)(te)龍(long)(long)牙齒(chi)(chi)更多,有(you)(you)70顆(ke),而(er)(er)且每(mei)(mei)顆(ke)牙齒(chi)(chi)像匕首一樣鋒(feng)利(li),所有(you)(you)的(de)(de)牙齒(chi)(chi)向后彎曲,用于撕(si)開獵物的(de)(de)肉。
異特(te)龍(long)(long)的(de)(de)(de)眼睛(jing)上(shang)(shang)方擁有(you)(you)一對角(jiao)冠(guan),由延伸的(de)(de)(de)淚骨(gu)所構(gou)成。角(jiao)冠(guan)的(de)(de)(de)形(xing)狀(zhuang)與大小隨著(zhu)個體而(er)不(bu)同(tong)。鼻骨(gu)的(de)(de)(de)上(shang)(shang)方也(ye)有(you)(you)一對低矮的(de)(de)(de)棱脊(ji),并沿者(zhe)鼻骨(gu),連(lian)接到眼睛(jing)上(shang)(shang)的(de)(de)(de)角(jiao)冠(guan)。這些角(jiao)冠(guan)可能覆蓋者(zhe)角(jiao)質(zhi),并具(ju)有(you)(you)不(bu)同(tong)的(de)(de)(de)功能,例如:替眼睛(jing)遮辟陽光、視覺展示(shi)物(wu)、以及(ji)物(wu)種(zhong)內的(de)(de)(de)打斗行(xing)為(問題(ti)是它們非常脆弱)。頭顱骨(gu)后(hou)上(shang)(shang)方也(ye)有(you)(you)一個棱脊(ji),可供(gong)肌肉附著(zhu),這特(te)征也(ye)可見于暴(bao)龍(long)(long)科(ke)動物(wu)。
淚骨(gu)內側有凹處,可(ke)(ke)能內藏腺(xian)體,例如(ru)鹽腺(xian)。上(shang)顎骨(gu)內側有凹陷(xian)處,發展的比基礎(chu)獸(shou)腳類恐龍的鼻竇還好,例如(ru)角鼻龍與馬什龍;這(zhe)些凹陷(xian)處可(ke)(ke)能與嗅覺器官有關(guan),例如(ru)犁鼻器。異特龍腦殼頂部(bu)較(jiao)薄,可(ke)(ke)能為促進(jin)腦部(bu)的體溫調(diao)節。
異(yi)特龍(long)的(de)頭(tou)顱(lu)骨(gu)是由(you)個別的(de)骨(gu)頭(tou)所組成,而(er)骨(gu)頭(tou)之(zhi)間有可(ke)活動關(guan)節(jie)。例如下(xia)顎(e)的(de)前半部(bu)(bu)與(yu)后半部(bu)(bu)可(ke)往外(wai)彎曲,增加骨(gu)頭(tou)間的(de)空(kong)隙,因此可(ke)以(yi)吞下(xia)較(jiao)大的(de)食物。腦殼與(yu)額骨(gu)之(zhi)間可(ke)能也有類似的(de)關(guan)節(jie)。
借助(zhu)下頜靈(ling)活的關節,異特龍的嘴可以張得很大(da),便(bian)于(yu)撕咬。這對獵物(wu)來說是致命的攻擊。
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(chu)應該不超過(guo)45節。頸椎(zhui)與前(qian)段背椎(zhui)有(you)(you)(you)中空區域,這種(zhong)(zhong)空間也可見(jian)于現(xian)(xian)代鳥類,被認(ren)為(wei)(wei)(wei)具有(you)(you)(you)類似鳥類的(de)(de)(de)(de)(de)氣囊系統,使用于呼吸作用上(shang)(shang)。異(yi)(yi)特(te)龍的(de)(de)(de)(de)(de)肋(lei)骨(gu)(gu)(gu)寬廣,形成桶狀胸腔(qiang),與較原始的(de)(de)(de)(de)(de)獸(shou)腳(jiao)類(例如角(jiao)鼻(bi)龍)不同。異(yi)(yi)特(te)龍也具有(you)(you)(you)腹(fu)肋(lei),但(dan)不常被發現(xian)(xian),可能有(you)(you)(you)稍微的(de)(de)(de)(de)(de)骨(gu)(gu)(gu)化(hua)。在(zai)一(yi)個已公布(bu)標本(ben)中,這些腹(fu)肋(lei)被發現(xian)(xian)生前(qian)曾(ceng)受過(guo)傷。有(you)(you)(you)一(yi)個叉骨(gu)(gu)(gu)被保存下來(lai),但(dan)直到1996年才(cai)被確認(ren)出(chu)來(lai);在(zai)一(yi)些案(an)例中,叉骨(gu)(gu)(gu)與腹(fu)肋(lei)則(ze)被混(hun)淆。主(zhu)要的(de)(de)(de)(de)(de)臀(tun)部骨(gu)(gu)(gu)頭腸骨(gu)(gu)(gu)巨大,恥(chi)骨(gu)(gu)(gu)有(you)(you)(you)個明顯的(de)(de)(de)(de)(de)尾端(duan),可能作為(wei)(wei)(wei)肌肉附著處,以及身體(ti)(ti)(ti)躺在(zai)地(di)面時(shi)的(de)(de)(de)(de)(de)支撐(cheng)物。在(zai)1976年,麥(mai)迪遜發現(xian)(xian)克利夫蘭勞埃德(de)恐(kong)龍采石(shi)場所發現(xian)(xian)的(de)(de)(de)(de)(de)異(yi)(yi)特(te)龍化(hua)石(shi),有(you)(you)(you)接近一(yi)半個體(ti)(ti)(ti)的(de)(de)(de)(de)(de)兩個恥(chi)骨(gu)(gu)(gu)上(shang)(shang)端(duan),并未互相固(gu)定者(zhe)。由于這個特(te)征(zheng)與體(ti)(ti)(ti)型(xing)無關,因此麥(mai)迪遜認(ren)為(wei)(wei)(wei)這是(shi)種(zhong)(zhong)兩性異(yi)(yi)形,雌性個體(ti)(ti)(ti)的(de)(de)(de)(de)(de)恥(chi)骨(gu)(gu)(gu)上(shang)(shang)端(duan)沒有(you)(you)(you)互相固(gu)定著,可使產(chan)卵(luan)時(shi)更為(wei)(wei)(wei)順利。然(ran)而,這個理論并未引起進一(yi)步(bu)的(de)(de)(de)(de)(de)討論。
與后肢(zhi)(zhi)(zhi)相比(bi),異特龍的(de)(de)(de)(de)(de)前(qian)肢(zhi)(zhi)(zhi)相當短(duan),但比(bi)暴龍要(yao)長很多,約是后肢(zhi)(zhi)(zhi)長度的(de)(de)(de)(de)(de)35%。每個手(shou)部具(ju)(ju)有(you)三(san)(san)根(gen)手(shou)指(zhi),以及大型、大幅彎曲的(de)(de)(de)(de)(de)指(zhi)爪。異特龍的(de)(de)(de)(de)(de)前(qian)肢(zhi)(zhi)(zhi)強壯,與其(qi)他的(de)(de)(de)(de)(de)獸腳類恐龍相比(bi),它們的(de)(de)(de)(de)(de)前(qian)肢(zhi)(zhi)(zhi)適合抓握一(yi)定距離內(nei)的(de)(de)(de)(de)(de)獵(lie)物,或是將獵(lie)物拉近。前(qian)臂(bei)稍短(duan)于上臂(bei),肱骨(gu)(gu)與尺骨(gu)(gu)的(de)(de)(de)(de)(de)比(bi)例為1:1.2。手(shou)腕(wan)具(ju)(ju)有(you)類似半(ban)新(xin)月形的(de)(de)(de)(de)(de)腕(wan)骨(gu)(gu),手(shou)盜龍類的(de)(de)(de)(de)(de)腕(wan)骨(gu)(gu)更為接近半(ban)新(xin)月形。異特龍的(de)(de)(de)(de)(de)三(san)(san)根(gen)手(shou)指(zhi)中,內(nei)側(ce)第一(yi)根(gen)手(shou)指(zhi)是最長的(de)(de)(de)(de)(de)。指(zhi)爪的(de)(de)(de)(de)(de)狀態顯示手(shou)指(zhi)可能(neng)用(yong)來鉤住東西。
通(tong)過研究遺(yi)骸(hai),我們(men)(men)了解到許多恐(kong)(kong)龍身(shen)(shen)體龐(pang)大(da)(da),但這不(bu)意味著他(ta)(ta)們(men)(men)很(hen)(hen)聰明。馬(ma)門溪(xi)龍活著的時候約有四五(wu)十噸重(zhong),而腦(nao)子重(zhong)量只(zhi)有500克左右。又如(ru)劍龍,他(ta)(ta)的身(shen)(shen)軀(qu)有大(da)(da)象那么大(da)(da),而腦(nao)子卻小得如(ru)約100克的核桃。異特龍也長著龐(pang)大(da)(da)的身(shen)(shen)體,但據(ju)推測,他(ta)(ta)的大(da)(da)腦(nao)可能很(hen)(hen)發達,是侏羅紀時期智(zhi)商最(zui)高的大(da)(da)型肉食恐(kong)(kong)龍,這也給它們(men)(men)的群居提(ti)供了方便。
異(yi)(yi)特(te)龍(long)(long)的(de)(de)大(da)(da)量(liang)化石(shi)(shi)幾乎涵蓋了所有(you)的(de)(de)年齡層,這使得科學家們(men)可以(yi)研究異(yi)(yi)特(te)龍(long)(long)的(de)(de)生長模式與年齡上限。在科羅拉(la)多州發(fa)(fa)現的(de)(de)一堆壓碎的(de)(de)蛋化石(shi)(shi),可能屬于(yu)(yu)異(yi)(yi)特(te)龍(long)(long),這是目前所發(fa)(fa)現最年幼的(de)(de)異(yi)(yi)特(te)龍(long)(long)化石(shi)(shi)。根據(ju)四(si)肢骨頭的(de)(de)組織(zhi)學分析,異(yi)(yi)特(te)龍(long)(long)的(de)(de)年齡上限大(da)(da)約(yue)為22到28歲(sui),相當于(yu)(yu)其他大(da)(da)型獸腳類恐(kong)龍(long)(long)(例如暴龍(long)(long))。異(yi)(yi)特(te)龍(long)(long)的(de)(de)最高生長率大(da)(da)約(yue)發(fa)(fa)生在15歲(sui)時,一年可以(yi)增加(jia)148公斤(jin)的(de)(de)體重。
已在一個(ge)出土(tu)於克利夫蘭(lan)勞埃德(de)的異(yi)特龍脛骨(gu),發現(xian)了骨(gu)髓(sui)(sui)骨(gu)組織。除了異(yi)特龍以外(wai),腱龍與暴龍也發現(xian)了骨(gu)髓(sui)(sui)骨(gu)。骨(gu)髓(sui)(sui)骨(gu)只(zhi)存在于產卵的雌(ci)(ci)性鳥類身上,骨(gu)髓(sui)(sui)骨(gu)富(fu)含鈣(gai),可用來制(zhi)造蛋殼的。異(yi)特龍的骨(gu)髓(sui)(sui)骨(gu)組織,顯示該個(ge)體是雌(ci)(ci)性的,而且正在繁衍期中。這(zhe)個(ge)雌(ci)(ci)性異(yi)特龍估計(ji)是在10歲(sui)時死亡,從此顯示異(yi)特龍在完全(quan)成(cheng)(cheng)長前,就(jiu)已達到性成(cheng)(cheng)熟(shu)。
一個(ge)具(ju)有幾乎完(wan)整后(hou)肢(zhi)的(de)(de)(de)幼(you)年(nian)(nian)異(yi)特(te)龍標本,顯(xian)示(shi)幼(you)年(nian)(nian)個(ge)體(ti)的(de)(de)(de)后(hou)肢(zhi)比例較(jiao)(jiao)成(cheng)年(nian)(nian)個(ge)體(ti)長(chang),而(er)(er)且后(hou)肢(zhi)下半部(小腿(tui)與(yu)腳(jiao)部)長(chang)於大(da)腿(tui)部分。這(zhe)些差別(bie)顯(xian)示(shi)年(nian)(nian)輕異(yi)特(te)龍的(de)(de)(de)移動速度較(jiao)(jiao)快,并(bing)具(ju)有不同(tong)于成(cheng)年(nian)(nian)個(ge)體(ti)的(de)(de)(de)獵食(shi)方(fang)式(shi),例如追趕(gan)小型獵物,而(er)(er)成(cheng)年(nian)(nian)個(ge)體(ti)則改(gai)采伏(fu)擊方(fang)式(shi)捕食(shi)大(da)型的(de)(de)(de)獵物。隨者(zhe)(zhe)異(yi)特(te)龍的(de)(de)(de)成(cheng)長(chang),它(ta)們的(de)(de)(de)大(da)腿(tui)骨頭變得更(geng)厚(hou)、更(geng)寬(kuan),而(er)(er)橫剖面變得較(jiao)(jiao)不圓(yuan)形,隨者(zhe)(zhe)肌(ji)肉附著點的(de)(de)(de)改(gai)變,肌(ji)肉相對更(geng)短,腿(tui)部的(de)(de)(de)成(cheng)長(chang)減緩。這(zhe)些改(gai)變顯(xian)示(shi)幼(you)年(nian)(nian)異(yi)特(te)龍的(de)(de)(de)腿(tui)部,承受的(de)(de)(de)應力較(jiao)(jiao)成(cheng)年(nian)(nian)異(yi)特(te)龍小,幼(you)年(nian)(nian)異(yi)特(te)龍可能以更(geng)規律的(de)(de)(de)速度前進。
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)適應演化(hua),例如:顎(e)(e)部肌肉的(de)縮小(xiao)、頸部肌肉的(de)增大、以及將顎(e)(e)部左右撐開的(de)能力(li)。雖然異特(te)龍的(de)牙齒(chi)(chi)并(bing)非如這些哺(bu)乳類呈軍刀狀,巴克提(ti)出了另一種(zhong)異特(te)龍的(de)攻(gong)擊方式:上顎(e)(e)的(de)短牙齒(chi)(chi)會形成(cheng)類似鋸(ju)子的(de)小(xiao)型(xing)鋸(ju)齒(chi)(chi)表面,可切入獵(lie)物肉體。這種(zhong)型(xing)態的(de)顎(e)(e)部可使(shi)異特(te)龍采(cai)取撕咬方式攻(gong)擊大型(xing)獵(lie)物,消耗獵(lie)物的(de)體力(li)。
埃(ai)米莉·雷菲爾德(Emily J. Rayfield)等人使用有限(xian)元分(fen)析,研(yan)究(jiu)了異(yi)特(te)龍(long)(long)的(de)(de)頭(tou)顱骨,也得到了類似的(de)(de)結(jie)果。根據(ju)其中(zhong)的(de)(de)生物(wu)力學研(yan)究(jiu)結(jie)果,異(yi)特(te)龍(long)(long)的(de)(de)頭(tou)顱骨非常強(qiang)壯,咬(yao)合(he)力相當大。異(yi)特(te)龍(long)(long)的(de)(de)咬(yao)合(he)力可(ke)(ke)以達到3-8噸,而且它(ta)們(men)(men)的(de)(de)頭(tou)顱可(ke)(ke)承受約55000牛(niu)頓(dun)來(lai)(lai)自于齒列的(de)(de)垂(chui)直壓強(qiang)。這個研(yan)究(jiu)也提出異(yi)特(te)龍(long)(long)使用頭(tou)部來(lai)(lai)撞(zhuang)擊(ji)(ji)獵物(wu),并張開大口、撕咬(yao)獵物(wu)。這個研(yan)究(jiu)認為異(yi)特(te)龍(long)(long)的(de)(de)頭(tou)部結(jie)構(gou)允(yun)(yun)許它(ta)們(men)(men)采取(qu)不同的(de)(de)獵食模式來(lai)(lai)攻擊(ji)(ji)不同的(de)(de)獵物(wu):它(ta)們(men)(men)的(de)(de)頭(tou)部較輕型,可(ke)(ke)攻擊(ji)(ji)較小、較靈活(huo)的(de)(de)鳥(niao)腳類恐龍(long)(long);但頭(tou)部有足夠的(de)(de)強(qiang)度承受撞(zhuang)擊(ji)(ji),可(ke)(ke)允(yun)(yun)取(qu)它(ta)們(men)(men)采取(qu)伏擊(ji)(ji)方式攻擊(ji)(ji)較大型的(de)(de)劍龍(long)(long)科與(yu)蜥腳類恐龍(long)(long)。
其(qi)他(ta)的(de)(de)(de)(de)科學(xue)家則對這個(ge)研究表(biao)示異(yi)(yi)議(yi),他(ta)們(men)認為(wei)現存生(sheng)物(wu)(wu)(wu)(wu)中沒(mei)有采取撞擊(ji)方式獵(lie)(lie)(lie)食(shi)的(de)(de)(de)(de)動物(wu)(wu)(wu)(wu),并(bing)(bing)提出異(yi)(yi)特(te)龍(long)的(de)(de)(de)(de)頭(tou)部有足(zu)夠(gou)的(de)(de)(de)(de)強度(du)(du),應可(ke)(ke)承受(shou)獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)掙(zheng)扎的(de)(de)(de)(de)力量(liang)。雷菲爾德等人對異(yi)(yi)議(yi)提出回應,他(ta)們(men)承認現存生(sheng)物(wu)(wu)(wu)(wu)中沒(mei)有類(lei)似(si)異(yi)(yi)特(te)龍(long)的(de)(de)(de)(de)動物(wu)(wu)(wu)(wu),但異(yi)(yi)特(te)龍(long)的(de)(de)(de)(de)齒列適(shi)合(he)這種(zhong)攻擊(ji)方式,而它們(men)的(de)(de)(de)(de)頭(tou)部結構(gou)可(ke)(ke)保護上顎、減低承受(shou)力量(liang)。另一種(zhong)可(ke)(ke)能則是,獸腳類(lei)恐(kong)龍(long)(例(li)如(ru)異(yi)(yi)特(te)龍(long))不必費力將獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)殺死,而是從活生(sheng)的(de)(de)(de)(de)蜥(xi)腳類(lei)恐(kong)龍(long)身上咬下足(zu)夠(gou)的(de)(de)(de)(de)肉(rou)塊,肉(rou)塊的(de)(de)(de)(de)大小(xiao)(xiao)只需維持獵(lie)(lie)(lie)食(shi)者(zhe)生(sheng)存即(ji)可(ke)(ke)。這種(zhong)獵(lie)(lie)(lie)食(shi)方式也使獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)有機會痊愈(yu),而獵(lie)(lie)(lie)食(shi)者(zhe)也可(ke)(ke)能以類(lei)似(si)的(de)(de)(de)(de)方式再度(du)(du)獵(lie)(lie)(lie)食(shi)。另外,鳥(niao)腳類(lei)恐(kong)龍(long)是當(dang)地(di)最常(chang)見的(de)(de)(de)(de)獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu),因(yin)此異(yi)(yi)特(te)龍(long)可(ke)(ke)能采偷襲方式獵(lie)(lie)(lie)食(shi)鳥(niao)腳類(lei)恐(kong)龍(long),使用前肢(zhi)抓住獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu),并(bing)(bing)咬斷獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)喉(hou)嚨的(de)(de)(de)(de)氣管(guan),類(lei)似(si)今日的(de)(de)(de)(de)大型貓科動物(wu)(wu)(wu)(wu)。異(yi)(yi)特(te)龍(long)的(de)(de)(de)(de)前肢(zhi)強壯,能夠(gou)抓緊獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu),所以這個(ge)獵(lie)(lie)(lie)食(shi)方式是可(ke)(ke)能成立(li)的(de)(de)(de)(de)。其(qi)他(ta)影響進食(shi)方式的(de)(de)(de)(de)因(yin)素包含(han):眼睛(jing)、前肢(zhi)、以及后肢(zhi)。異(yi)(yi)特(te)龍(long)的(de)(de)(de)(de)頭(tou)部形狀將立(li)體視(shi)覺限制在20°的(de)(de)(de)(de)范(fan)圍(wei)內,略(lve)小(xiao)(xiao)于現代鱷魚(yu)。如(ru)同鱷魚(yu),這個(ge)范(fan)圍(wei)已足(zu)夠(gou)異(yi)(yi)特(te)龍(long)判斷獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)的(de)(de)(de)(de)距離(li)與攻擊(ji)時機。相較于其(qi)他(ta)獸腳類(lei)恐(kong)龍(long),異(yi)(yi)特(te)龍(long)的(de)(de)(de)(de)前肢(zhi)適(shi)合(he)抓住一定距離(li)的(de)(de)(de)(de)獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu),還(huan)有將獵(lie)(lie)(lie)物(wu)(wu)(wu)(wu)拉(la)近;而指爪的(de)(de)(de)(de)構(gou)造顯示它們(men)可(ke)(ke)用來勾取物(wu)(wu)(wu)(wu)體。經(jing)推算,異(yi)(yi)特(te)龍(long)的(de)(de)(de)(de)最高奔跑速度(du)(du)可(ke)(ke)達(da)每小(xiao)(xiao)時30到55公里。
長久以(yi)(yi)來(lai),半(ban)科學文獻(xian)與(yu)大眾讀物都將異特(te)(te)龍描述成(cheng)以(yi)(yi)群體方式獵食(shi)(shi),并(bing)以(yi)(yi)蜥腳類恐龍與(yu)其他(ta)大型(xing)恐龍為獵食(shi)(shi)對(dui)象。羅伯(bo)特(te)(te)·巴克(Robert T.Bakker)從脫落的牙齒(chi)、大型(xing)獵物的被咬過骨頭研判,異特(te)(te)龍具有親(qin)代養(yang)育的社會行為。巴克認為成(cheng)年異特(te)(te)龍將食(shi)(shi)物帶(dai)到巢穴中,以(yi)(yi)供(gong)幼年異特(te)(te)龍食(shi)(shi)用,并(bing)防止其他(ta)肉(rou)食(shi)(shi)性動物找到它們的食(shi)(shi)物。
研究(jiu)(jiu)提出(chu)異特龍(long)(long)(long)與其他獸腳類(lei)恐龍(long)(long)(long)具有侵略(lve)性(xing)(xing)的(de)(de)(de)(de)(de)(de)(de)物(wu)種(zhong)(zhong)內行為(wei)(wei)(wei),而(er)非(fei)(fei)合(he)作(zuo)(zuo)性(xing)(xing)的(de)(de)(de)(de)(de)(de)(de)行為(wei)(wei)(wei),如(ru)同(tong)(tong)其他的(de)(de)(de)(de)(de)(de)(de)雙(shuang)弓(gong)動(dong)物(wu)。一個(ge)(ge)研究(jiu)(jiu)則(ze)推論獸腳類(lei)恐龍(long)(long)(long)會合(he)作(zuo)(zuo)獵(lie)食(shi)(shi)(shi),而(er)非(fei)(fei)個(ge)(ge)別獵(lie)食(shi)(shi)(shi);這種(zhong)(zhong)行為(wei)(wei)(wei)在(zai)脊椎(zhui)動(dong)物(wu)中較(jiao)(jiao)少見,而(er)現存(cun)雙(shuang)弓(gong)動(dong)物(wu)(包括蜥蜴(yi)、鱷(e)(e)魚、鳥類(lei))很(hen)少合(he)作(zuo)(zuo)獵(lie)食(shi)(shi)(shi)。許多(duo)現代的(de)(de)(de)(de)(de)(de)(de)掠食(shi)(shi)(shi)性(xing)(xing)雙(shuang)弓(gong)動(dong)物(wu)是領域性(xing)(xing),會將侵入(ru)領地的(de)(de)(de)(de)(de)(de)(de)同(tong)(tong)類(lei)殺死、并(bing)吞食(shi)(shi)(shi)它們(men)的(de)(de)(de)(de)(de)(de)(de)尸體;另外當聚集(ji)在(zai)食(shi)(shi)(shi)物(wu)周圍(wei)時,它們(men)會將企圖(tu)搶先(xian)的(de)(de)(de)(de)(de)(de)(de)較(jiao)(jiao)小個(ge)(ge)體殺死。克(ke)利(li)夫蘭勞(lao)埃德采石(shi)場的(de)(de)(de)(de)(de)(de)(de)大量異特龍(long)(long)(long)化石(shi)可能源于它們(men)在(zai)同(tong)(tong)類(lei)相(xiang)食(shi)(shi)(shi)時被淹(yan)死。這也(ye)可以解釋(shi)異特龍(long)(long)(long)化石(shi)中,幼(you)年(nian)與近(jin)成(cheng)年(nian)個(ge)(ge)體所(suo)占的(de)(de)(de)(de)(de)(de)(de)比(bi)例較(jiao)(jiao)高;因為(wei)(wei)(wei)在(zai)現代的(de)(de)(de)(de)(de)(de)(de)鱷(e)(e)魚與科莫多(duo)龍(long)(long)(long)中,幼(you)年(nian)與近(jin)成(cheng)年(nian)個(ge)(ge)體較(jiao)(jiao)少在(zai)聚食(shi)(shi)(shi)地點中被殺死。這理論也(ye)可解釋(shi)巴(ba)克(ke)所(suo)發現的(de)(de)(de)(de)(de)(de)(de)巢穴(xue)狀況(kuang)。有些證據(ju)顯示異特龍(long)(long)(long)具有同(tong)(tong)類(lei)相(xiang)食(shi)(shi)(shi)的(de)(de)(de)(de)(de)(de)(de)行為(wei)(wei)(wei),例如(ru)肋骨碎(sui)片上有脫(tuo)落的(de)(de)(de)(de)(de)(de)(de)同(tong)(tong)類(lei)牙(ya)齒(chi)、一個(ge)(ge)肩胛骨上有可能的(de)(de)(de)(de)(de)(de)(de)齒(chi)痕、巴(ba)克(ke)所(suo)發現的(de)(de)(de)(de)(de)(de)(de)巢穴(xue)中的(de)(de)(de)(de)(de)(de)(de)異特龍(long)(long)(long)骨骸可能遭到同(tong)(tong)類(lei)相(xiang)食(shi)(shi)(shi)。
一(yi)個(ge)針對異(yi)特龍(long)腦(nao)(nao)部的(de)(de)(de)電腦(nao)(nao)斷層掃描,發現它們(men)的(de)(de)(de)腦(nao)(nao)部與鱷魚和鳥類有較多的(de)(de)(de)共(gong)同(tong)點。前庭(ting)器官的(de)(de)(de)結構顯示它們(men)的(de)(de)(de)頭部保(bao)持在幾乎(hu)水平(ping)的(de)(de)(de)位置,而非朝上或朝下。內(nei)耳的(de)(de)(de)結構類似鱷魚,所以異(yi)特龍(long)可能容易聽(ting)到低頻的(de)(de)(de)聲音(yin),也可以聽(ting)到細微的(de)(de)(de)聲音(yin)。異(yi)特龍(long)的(de)(de)(de)嗅球大,可能適合感覺氣味。
早在1869年(nian),科羅拉多州格蘭比郡附近的(de)(de)中央公園d當地居民將一(yi)(yi)個馬(ma)(ma)蹄(ti)化(hua)石交給了費(fei)迪(di)(di)(di)南德·范(fan)迪(di)(di)(di)威爾(er)·海登(Ferdinand Vandiveer Hayden);該地可(ke)能屬(shu)(shu)于莫(mo)里(li)遜組(zu)。海登將這(zhe)標(biao)本交給約瑟夫·萊(lai)迪(di)(di)(di)(Joseph Leidy),萊(lai)迪(di)(di)(di)發現這(zhe)個"馬(ma)(ma)蹄(ti)"化(hua)石其實是半節(jie)尾椎骨(gu)。約瑟夫·萊(lai)迪(di)(di)(di)起初(chu)暫(zan)時將它歸類為歐(ou)洲(zhou)雜肋(lei)龍的(de)(de)一(yi)(yi)個種(Poicilopleurodon valens)。萊(lai)迪(di)(di)(di)后(hou)來將它建立(li)為一(yi)(yi)個新的(de)(de)屬(shu)(shu),腔軀龍(Antrodemus)。
異特龍(long)的原型標本(ben)(編號(hao)YPM 1930)被(bei)發(fa)現于科(ke)羅拉(la)多州卡農城(cheng)北方的花(hua)園(yuan)公園(yuan),由一(yi)小(xiao)群破碎骨(gu)頭所構成,包含三節脊椎(zhui)、一(yi)個肋骨(gu)碎片、一(yi)顆牙(ya)齒、一(yi)個趾骨(gu)、以及右肱骨(gu)主(zhu)干部分;而(er)右肱骨(gu)最常被(bei)后來(lai)的研究(jiu)提及。在1877年,奧塞內(nei)爾·查(cha)利斯·馬什(Othniel Charles Marsh)根據這些化石,把這種生物定名為異特龍(long),并把其(qi)模(mo)式種正式命名為脆弱(ruo)異特龍(long)(Allosaurus fragilis)。種名fragilis來(lai)自拉(la)丁語,意即"脆弱(ruo)的",是指它(ta)們脊椎(zhui)骨(gu)的輕盈特點。
在18世紀后期的(de)化石戰爭(zheng)期間,馬什與(yu)愛德華·德林克·科(ke)普(Edward Drinker Cope)之間有(you)過激烈的(de)競爭(zheng)。兩(liang)(liang)人(ren)曾根據許多零散、相似的(de)化石建立了數個屬,但之后被證(zheng)明屬于異(yi)特龍,使得異(yi)特龍的(de)發現與(yu)早期研(yan)究(jiu)非常復雜。兩(liang)(liang)人(ren)所建立的(de)名稱包(bao)含:馬什命(ming)名的(de)Creosaurus(意(yi)為(wei)(wei)"肌(ji)肉蜥(xi)蜴")、Labrosaurus(意(yi)為(wei)(wei)"貪吃的(de)蜥(xi)蜴")、以及科(ke)普命(ming)名的(de)Epanterias(意(yi)為(wei)(wei)"拱起的(de)")。
在(zai)(zai)競爭的(de)(de)過程(cheng)(cheng)中(zhong)(zhong),科(ke)(ke)(ke)(ke)普(pu)與(yu)馬什并沒有(you)持續地(di)進行他(ta)們與(yu)他(ta)們下屬的(de)(de)挖(wa)掘(jue)工作(zuo)。舉例而言,班杰明·福蘭克林·馬奇(Benjamin Franklin Mudge)在(zai)(zai)科(ke)(ke)(ke)(ke)羅拉(la)多州(zhou)(zhou)花(hua)園公(gong)園發現(xian)(xian)異(yi)特(te)(te)龍的(de)(de)原型標本(ben)后(hou)(hou),馬什便轉向懷俄(e)明州(zhou)(zhou)進行新的(de)(de)挖(wa)掘(jue)工作(zuo);而在(zai)(zai)1883年,M.P.Felch重新開始花(hua)園公(gong)園的(de)(de)挖(wa)掘(jue)工作(zuo)后(hou)(hou),卻發現(xian)(xian)了一(yi)個幾乎完(wan)整的(de)(de)異(yi)特(te)(te)龍化(hua)石,以(yi)及數個部分骸骨。另外,科(ke)(ke)(ke)(ke)普(pu)的(de)(de)一(yi)個挖(wa)掘(jue)工人(ren)H.F.Hubbell,在(zai)(zai)1879年于懷俄(e)明州(zhou)(zhou)的(de)(de)科(ke)(ke)(ke)(ke)摩崖發現(xian)(xian)了一(yi)個異(yi)特(te)(te)龍標本(ben)(編號(hao)AMNH 5753),但他(ta)沒有(you)提到化(hua)石的(de)(de)完(wan)整程(cheng)(cheng)度,所(suo)以(yi)科(ke)(ke)(ke)(ke)普(pu)從未看過這(zhe)個化(hua)石。在(zai)(zai)1903年,科(ke)(ke)(ke)(ke)普(pu)死(si)后(hou)(hou)數年,這(zhe)個標本(ben)被發現(xian)(xian)是當(dang)時最完(wan)整的(de)(de)獸(shou)腳(jiao)類恐龍之(zhi)一(yi),并在(zai)(zai)1908年開始展覽。在(zai)(zai)一(yi)個由查爾(er)斯·耐特(te)(te)(Charles R.Knight)所(suo)繪制(zhi)的(de)(de)圖畫中(zhong)(zhong),編號(hao)AMNH 5753的(de)(de)異(yi)特(te)(te)龍跨(kua)越在(zai)(zai)一(yi)只(zhi)迷(mi)惑(huo)龍身上(shang),吞食(shi)著迷(mi)惑(huo)龍的(de)(de)尸體。雖(sui)然這(zhe)是第(di)一(yi)次(ci)將獸(shou)腳(jiao)類恐龍描繪成(cheng)站立姿態(tai),但當(dang)時并沒有(you)科(ke)(ke)(ke)(ke)學證據(ju)可以(yi)支持。
異(yi)(yi)特(te)(te)(te)龍(long)(long)名(ming)(ming)稱(cheng)(cheng)的(de)重(zhong)復(fu)(fu)使得(de)研究變(bian)的(de)復(fu)(fu)雜,并隨者馬什(shen)與(yu)科普的(de)競爭而(er)惡化(hua)。在當時便(bian)有一(yi)(yi)些(xie)科學家(jia),例如塞繆爾(er)(er)·溫德(de)爾(er)(er)·威(wei)利斯頓(Samuel Wendell Williston),提出(chu)有太多相關名(ming)(ming)稱(cheng)(cheng)被重(zhong)復(fu)(fu)建立。在1901年(nian),威(wei)利斯頓便(bian)指出(chu)馬什(shen)自(zi)己也無法(fa)分辨出(chu)異(yi)(yi)特(te)(te)(te)龍(long)(long)與(yu)Creosaurus的(de)差異(yi)(yi)。查爾(er)(er)斯·懷特(te)(te)(te)尼(ni)·吉爾(er)(er)摩爾(er)(er)(Charles W.Gilmore)在1920年(nian)嘗(chang)試(shi)將這些(xie)復(fu)(fu)雜的(de)名(ming)(ming)稱(cheng)(cheng)整理、歸類。吉爾(er)(er)摩爾(er)(er)認為(wei)萊迪(di)用(yong)來(lai)命名(ming)(ming)腔軀龍(long)(long)的(de)尾(wei)椎,其實跟異(yi)(yi)特(te)(te)(te)龍(long)(long)的(de)尾(wei)椎一(yi)(yi)樣;因為(wei)腔軀龍(long)(long)較早命名(ming)(ming),所以取(qu)代(dai)異(yi)(yi)特(te)(te)(te)龍(long)(long)。在接下來(lai)的(de)50年(nian),腔軀龍(long)(long)取(qu)代(dai)異(yi)(yi)特(te)(te)(te)龍(long)(long),成(cheng)為(wei)正式的(de)名(ming)(ming)稱(cheng)(cheng),直到詹(zhan)姆斯·麥迪(di)遜在克利夫(fu)蘭勞埃德(de)采(cai)石場發現新的(de)異(yi)(yi)特(te)(te)(te)龍(long)(long)化(hua)石,并出(chu)腔軀龍(long)(long)的(de)化(hua)石材(cai)料(liao)無法(fa)鑒定,發現地點(dian)也不(bu)清楚,應(ying)該采(cai)用(yong)異(yi)(yi)特(te)(te)(te)龍(long)(long)這名(ming)(ming)稱(cheng)(cheng)。腔軀龍(long)(long)為(wei)非正式的(de)用(yong)法(fa),只用(yong)在區分吉爾(er)(er)摩爾(er)(er)與(yu)麥迪(di)遜兩人重(zhong)建的(de)不(bu)同形態頭顱(lu)骨。
早在1927年(nian)(nian)開始,猶他州(zhou)艾麥(mai)里(li)縣的(de)(de)(de)克(ke)利(li)夫蘭勞埃德恐(kong)龍(long)(long)(long)(long)(long)(long)采(cai)(cai)石場(chang)(chang)(chang)便(bian)有了(le)零散的(de)(de)(de)發現(xian),威廉·斯托克(ke)斯(William J. Stokes)在1945年(nian)(nian)于(yu)(yu)(yu)《科(ke)學(xue)》雜志(zhi)描述了(le)這個(ge)(ge)(ge)采(cai)(cai)石場(chang)(chang)(chang),但直到(dao)60年(nian)(nian)代(dai),才開始了(le)大(da)(da)(da)型的(de)(de)(de)挖掘計畫(hua)。在1960年(nian)(nian)到(dao)1965年(nian)(nian)期間,在接近40個(ge)(ge)(ge)機構(gou)的(de)(de)(de)合(he)力挖掘之下(xia),該采(cai)(cai)石場(chang)(chang)(chang)出(chu)(chu)土(tu)了(le)數千塊骨頭。克(ke)利(li)夫蘭勞埃德采(cai)(cai)石場(chang)(chang)(chang)的(de)(de)(de)著名(ming)原因(yin)(yin)包含:大(da)(da)(da)部分骨頭都屬于(yu)(yu)(yu)脆(cui)弱異(yi)特(te)龍(long)(long)(long)(long)(long)(long),例如(ru)在2006年(nian)(nian),73個(ge)(ge)(ge)出(chu)(chu)土(tu)的(de)(de)(de)恐(kong)龍(long)(long)(long)(long)(long)(long)個(ge)(ge)(ge)體中(zhong)(zhong),至少有46個(ge)(ge)(ge)屬于(yu)(yu)(yu)脆(cui)弱異(yi)特(te)龍(long)(long)(long)(long)(long)(long);這些化(hua)(hua)石不呈天(tian)然狀(zhuang)態,而且互相混合(he);將近有10多個(ge)(ge)(ge)科(ke)學(xue)研究(jiu)討論了(le)該地(di)點的(de)(de)(de)化(hua)(hua)石埋(mai)葬狀(zhuang)況,形成(cheng)(cheng)不同、互相矛盾(dun)的(de)(de)(de)解釋。對于(yu)(yu)(yu)該地(di)的(de)(de)(de)成(cheng)(cheng)因(yin)(yin),包含大(da)(da)(da)群動物深陷在泥(ni)濘之中(zhong)(zhong)、乾(qian)旱導(dao)致大(da)(da)(da)群動物困在水洼之中(zhong)(zhong)。無(wu)論正確的(de)(de)(de)成(cheng)(cheng)因(yin)(yin)為何(he),當地(di)發現(xian)的(de)(de)(de)大(da)(da)(da)量異(yi)特(te)龍(long)(long)(long)(long)(long)(long)化(hua)(hua)石使(shi)得科(ke)學(xue)家可以詳細(xi)地(di)研究(jiu)它們,使(shi)得異(yi)特(te)龍(long)(long)(long)(long)(long)(long)成(cheng)(cheng)為了(le)解最多的(de)(de)(de)獸腳類(lei)恐(kong)龍(long)(long)(long)(long)(long)(long)之一(yi)。該地(di)所(suo)出(chu)(chu)土(tu)的(de)(de)(de)異(yi)特(te)龍(long)(long)(long)(long)(long)(long)化(hua)(hua)石幾乎包含各(ge)種年(nian)(nian)齡與(yu)大(da)(da)(da)小,身長范圍從1公尺到(dao)9公尺。
自從麥(mai)迪遜的(de)(de)專題論(lun)文公(gong)布以來,已有許多研(yan)究討(tao)論(lun)異特龍(long)的(de)(de)古生(sheng)物學以及(ji)古生(sheng)態(tai)學。這些研(yan)究涵蓋(gai)了異特龍(long)的(de)(de)骨骼差異、生(sheng)長模(mo)(mo)式、頭顱骨重(zhong)建、獵食模(mo)(mo)式、腦部構造、以及(ji)群居生(sheng)活與親(qin)代養(yang)育(yu)的(de)(de)可能性。早期異特龍(long)標(biao)本(ben)的(de)(de)重(zhong)新(xin)(xin)研(yan)究、在葡萄牙(ya)新(xin)(xin)發(fa)現(xian)的(de)(de)化石、以及(ji)數個非常完整的(de)(de)標(biao)本(ben)也有助于對異特龍(long)的(de)(de)了解。
在(zai)1991年發(fa)現(xian)(xian)的(de)"大(da)艾(ai)(ai)爾(er)"標本(ben)(編號(hao)MOR 593),是(shi)最(zui)(zui)著名的(de)異(yi)特(te)龍化(hua)石(shi)之一。"大(da)艾(ai)(ai)爾(er)"是(shi)個相當完整的(de)天然狀態標本(ben),接(jie)近95%完整度,身長約8米。"大(da)艾(ai)(ai)爾(er)"最(zui)(zui)初是(shi)由卡比·希伯(Kirby Siber)所率領(ling)的(de)瑞(rui)士團(tuan)隊發(fa)現(xian)(xian)于懷俄明州的(de)比格霍恩縣,并由懷俄明大(da)學地理博(bo)物(wu)館與洛(luo)磯山博(bo)物(wu)館共(gong)同挖掘出土(tu)。因為(wei)(wei)該(gai)化(hua)石(shi)相當完整,因此取了個昵稱:"大(da)艾(ai)(ai)爾(er)"。發(fa)現(xian)(xian)"大(da)艾(ai)(ai)爾(er)"的(de)瑞(rui)士團(tuan)隊后來(lai)在(zai)同一地點發(fa)現(xian)(xian)另一異(yi)特(te)龍化(hua)石(shi),并取名為(wei)(wei)"大(da)艾(ai)(ai)爾(er)二號(hao)",這具化(hua)石(shi)是(shi)到(dao)目前為(wei)(wei)止,保存狀態最(zui)(zui)好(hao)的(de)異(yi)特(te)龍化(hua)石(shi)。
"大(da)(da)艾爾(er)"的(de)體型小(xiao)于(yu)脆弱異(yi)特龍的(de)平均大(da)(da)小(xiao),可(ke)能是個(ge)(ge)(ge)近成年體,估計(ji)只成長到了(le)87%,或是另一較(jiao)小(xiao)的(de)種(zhong)。"大(da)(da)艾爾(er)"由(you)布(bu)倫特·布(bu)萊特豪普特(Brent Breithaupt)是在1996年所敘述。其中(zhong)有19個(ge)(ge)(ge)骨頭(tou)是斷裂的(de),呈現出感(gan)染(ran)的(de)跡象,這可(ke)能導致"大(da)(da)艾爾(er)"的(de)死亡(wang)。這些感(gan)染(ran)的(de)骨頭(tou)包含(han)五(wu)個(ge)(ge)(ge)肋骨、五(wu)節脊椎、四個(ge)(ge)(ge)腳(jiao)(jiao)(jiao)部骨頭(tou);數個(ge)(ge)(ge)骨頭(tou)則具有骨髓炎。右腳(jiao)(jiao)(jiao)上的(de)感(gan)染(ran)與傷口(kou)可(ke)能影響了(le)"大(da)(da)艾爾(er)"的(de)行(xing)走(zou),從步態的(de)改變研判,右腳(jiao)(jiao)(jiao)的(de)傷口(kou)可(ke)能感(gan)染(ran)了(le)另一只腳(jiao)(jiao)(jiao)。
異特(te)龍是(shi)美(mei)國(guo)西(xi)部莫(mo)里(li)遜組地(di)層中最(zui)常見的大型獸腳亞(ya)目化石,它們位在(zai)該地(di)食(shi)物鏈的最(zui)上(shang)層。莫(mo)里(li)遜組被認為是(shi)半干旱的環境(jing),具有明顯的雨季(ji)和旱季(ji),地(di)形為平(ping)(ping)坦的泛濫平(ping)(ping)原。該地(di)層的植被是(shi)由針(zhen)葉(xie)樹(shu)、樹(shu)蕨(jue)、蕨(jue)類所構成(cheng)的樹(shu)林,以及由蕨(jue)類所構成(cheng)的疏林莽(mang)原。
莫里遜(xun)組是個富含(han)化(hua)石的(de)(de)(de)(de)挖掘地點,該地曾(ceng)發現綠藻(zao)、真菌、苔蘚、木賊、蕨類、蘇鐵、銀杏(xing)、以及數科針(zhen)葉樹等植(zhi)物化(hua)石;其(qi)他的(de)(de)(de)(de)動(dong)物化(hua)石則包(bao)(bao)含(han):雙(shuang)殼綱、蝸牛、輻鰭魚綱、青蛙、蠑螈、烏龜、喙頭(tou)目(mu)、蜥蜴、陸生(sheng)與(yu)水生(sheng)的(de)(de)(de)(de)鱷(e)形(xing)超(chao)目(mu)、數種翼龍(long)目(mu)、大量的(de)(de)(de)(de)恐龍(long)、以及早(zao)期的(de)(de)(de)(de)哺乳(ru)類,例如:柱齒獸目(mu)、多瘤(liu)齒目(mu)、對(dui)齒獸目(mu)、三尖齒獸目(mu)。莫里遜(xun)組所發現的(de)(de)(de)(de)恐龍(long)則包(bao)(bao)含(han)了獸腳亞目(mu)的(de)(de)(de)(de)角(jiao)鼻龍(long)、嗜鳥龍(long)、蠻(man)龍(long),蜥腳下目(mu)的(de)(de)(de)(de)迷惑(huo)龍(long)、腕(wan)龍(long)、圓頂龍(long)、梁龍(long),鳥臀(tun)目(mu)的(de)(de)(de)(de)彎龍(long)、橡樹龍(long)、劍(jian)龍(long)。
在猶(you)他州(zhou)的(de)(de)(de)(de)克利(li)夫(fu)蘭(lan)勞埃德采石(shi)場(chang),有(you)一個(ge)(ge)數(shu)量(liang)眾多的(de)(de)(de)(de)化石(shi)層(ceng)。這(zhe)個(ge)(ge)化石(shi)層(ceng)包含超過(guo)10,000個(ge)(ge)骨頭,大部分屬于(yu)異特龍(long)(long)(long)(long)(long)(long)(long)(long)化石(shi),但也有(you)其他恐(kong)龍(long)(long)(long)(long)(long)(long)(long)(long)化石(shi),例(li)如劍龍(long)(long)(long)(long)(long)(long)(long)(long)與角(jiao)鼻龍(long)(long)(long)(long)(long)(long)(long)(long)。如此眾多的(de)(de)(de)(de)動物(wu)化石(shi)為何集中(zhong)于(yu)同一地點,仍不(bu)清(qing)楚。而(er)且肉食(shi)性恐(kong)龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)(de)(de)比例(li)大于(yu)草食(shi)性恐(kong)龍(long)(long)(long)(long)(long)(long)(long)(long),這(zhe)種狀況非常的(de)(de)(de)(de)少見。這(zhe)個(ge)(ge)化石(shi)層(ceng)被(bei)(bei)解(jie)釋成群(qun)體獵食(shi)所(suo)造成的(de)(de)(de)(de),但很難(nan)證實。另一個(ge)(ge)可能性是(shi)克利(li)夫(fu)蘭(lan)勞埃德恐(kong)龍(long)(long)(long)(long)(long)(long)(long)(long)采石(shi)場(chang)在過(guo)去是(shi)個(ge)(ge)"掠(lve)食(shi)者(zhe)陷(xian)阱",類似拉布雷亞(ya)瀝(li)青坑,造成大量(liang)的(de)(de)(de)(de)掠(lve)食(shi)者(zhe)陷(xian)入(ru)無法掙(zheng)脫的(de)(de)(de)(de)沉積層(ceng)中(zhong)。葡(pu)(pu)萄(tao)牙(ya)所(suo)發現異特龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)(de)(de)地層(ceng),年代屬于(yu)晚侏(zhu)羅(luo)紀,被(bei)(bei)認為環境類似莫里遜組,但受到海洋的(de)(de)(de)(de)影響較多。這(zhe)個(ge)(ge)葡(pu)(pu)萄(tao)牙(ya)地層(ceng)也發現了許多莫里遜組的(de)(de)(de)(de)恐(kong)龍(long)(long)(long)(long)(long)(long)(long)(long),主要有(you)異特龍(long)(long)(long)(long)(long)(long)(long)(long)、角(jiao)鼻龍(long)(long)(long)(long)(long)(long)(long)(long)、蠻龍(long)(long)(long)(long)(long)(long)(long)(long)、迷惑龍(long)(long)(long)(long)(long)(long)(long)(long),或者(zhe)是(shi)相(xiang)近(jin)(jin)物(wu)種,例(li)如腕龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)(de)(de)近(jin)(jin)親葡(pu)(pu)萄(tao)牙(ya)巨(ju)龍(long)(long)(long)(long)(long)(long)(long)(long)、彎(wan)龍(long)(long)(long)(long)(long)(long)(long)(long)的(de)(de)(de)(de)近(jin)(jin)親龍(long)(long)(long)(long)(long)(long)(long)(long)爪龍(long)(long)(long)(long)(long)(long)(long)(long)。
異(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)與(yu)其他(ta)侏羅紀獸(shou)腳(jiao)(jiao)類恐(kong)龍(long)(long)(long)(long)(long)(long)共同生存在(zai)莫里遜組(zu)與(yu)葡萄牙,包含(han):角(jiao)(jiao)(jiao)鼻龍(long)(long)(long)(long)(long)(long)、體型(xing)較(jiao)大(da)的(de)(de)(de)蠻(man)龍(long)(long)(long)(long)(long)(long),食(shi)(shi)蜥(xi)王(wang)龍(long)(long)(long)(long)(long)(long),依(yi)潘龍(long)(long)(long)(long)(long)(long)。這點(dian)很(hen)不(bu)尋常。根據生理結構與(yu)化石(shi)位(wei)置,它們(men)三者似(si)乎擁有(you)不(bu)同的(de)(de)(de)生態(tai)位(wei)。角(jiao)(jiao)(jiao)鼻龍(long)(long)(long)(long)(long)(long)與(yu)蠻(man)龍(long)(long)(long)(long)(long)(long)可能活(huo)躍(yue)于(yu)河道附近,角(jiao)(jiao)(jiao)鼻龍(long)(long)(long)(long)(long)(long)身體較(jiao)細,叫矮(ai)(ai),而蠻(man)龍(long)(long)(long)(long)(long)(long)則(ze)十(shi)分粗壯,擁有(you)威(wei)力巨大(da)的(de)(de)(de)爪子和威(wei)力無窮的(de)(de)(de)放(fang)血牙加碎骨牙,但體型(xing)至(zhi)少有(you)10-12米(mi)+,可使它們(men)躲藏(zang)在(zai)森林中(zhong)(zhong)突襲迷(mi)惑龍(long)(long)(long)(long)(long)(long),腕龍(long)(long)(long)(long)(long)(long)這類大(da)型(xing)蜥(xi)腳(jiao)(jiao)類,有(you)時(shi)也(ye)會去捕獵劍龍(long)(long)(long)(long)(long)(long)家族的(de)(de)(de)成員;異(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)腿部較(jiao)長、速度(du)較(jiao)快(kuai),但它們(men)在(zai)森林或矮(ai)(ai)樹叢中(zhong)(zhong)較(jiao)不(bu)靈活(huo),因(yin)此可能活(huo)躍(yue)于(yu)干燥的(de)(de)(de)泛濫平(ping)原中(zhong)(zhong)。對于(yu)角(jiao)(jiao)(jiao)鼻龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)研(yan)究比蠻(man)龍(long)(long)(long)(long)(long)(long)還深入(ru)。角(jiao)(jiao)(jiao)鼻龍(long)(long)(long)(long)(long)(long)與(yu)異(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)差(cha)別在(zai)于(yu),它們(men)的(de)(de)(de)頭顱骨較(jiao)高(gao)、較(jiao)狹(xia)窄(zhai),而牙齒(chi)較(jiao)大(da)、較(jiao)寬廣。在(zai)一個異(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)恥(chi)骨末端發現了另一個獸(shou)腳(jiao)(jiao)類恐(kong)龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)齒(chi)痕,可能是由(you)角(jiao)(jiao)(jiao)鼻龍(long)(long)(long)(long)(long)(long)或蠻(man)龍(long)(long)(long)(long)(long)(long)所(suo)留下(xia)的(de)(de)(de),異(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)可能也(ye)是其他(ta)獸(shou)腳(jiao)(jiao)類恐(kong)龍(long)(long)(long)(long)(long)(long)的(de)(de)(de)食(shi)(shi)物(wu)來源選擇之(zhi)一,但是恥(chi)骨是位(wei)于(yu)腹部下(xia)緣,夾在(zai)兩腿之(zhi)間,處于(yu)身體最(zui)龐大(da)的(de)(de)(de)地方(fang)之(zhi)一。顯示這只異(yi)特(te)(te)龍(long)(long)(long)(long)(long)(long)是在(zai)死后,尸體被其他(ta)恐(kong)龍(long)(long)(long)(long)(long)(long)所(suo)吞(tun)食(shi)(shi)。
在大眾文化(hua)(hua)中,異(yi)特(te)龍(long)(long)(long)(long)(long)與暴龍(long)(long)(long)(long)(long)皆是大型肉食性恐龍(long)(long)(long)(long)(long)的(de)(de)代表。異(yi)特(te)龍(long)(long)(long)(long)(long)也是博物館常(chang)見的(de)(de)恐龍(long)(long)(long)(long)(long)之一,部分(fen)原因(yin)為(wei)克(ke)利夫蘭(lan)勞(lao)埃德恐龍(long)(long)(long)(long)(long)采石(shi)(shi)(shi)(shi)場所(suo)出(chu)土(tu)的(de)(de)大量異(yi)特(te)龍(long)(long)(long)(long)(long)化(hua)(hua)石(shi)(shi)(shi)(shi);到(dao)了1976年(nian),已經有三大洲、八(ba)個國(guo)家的(de)(de)38個博物館具(ju)有從克(ke)利夫蘭(lan)勞(lao)埃德恐龍(long)(long)(long)(long)(long)采石(shi)(shi)(shi)(shi)場所(suo)出(chu)土(tu)的(de)(de)異(yi)特(te)龍(long)(long)(long)(long)(long)化(hua)(hua)石(shi)(shi)(shi)(shi)。異(yi)特(te)龍(long)(long)(long)(long)(long)是猶他州的(de)(de)官方州恐龍(long)(long)(long)(long)(long)。
自20世紀初期(qi)開始,異特龍(long)(long)便已出現在大眾文化(hua)之中。在BBC(迷失的世界)中就出現過異特龍(long)(long)的身影并襲擊了主(zhu)角和(he)原始人,另外(wai)本片中有三只異特龍(long)(long)。
異特龍還短暫的(de)出現在(zai)2009年的(de)電影(ying)《失落的(de)大陸(lu)》在(zai)影(ying)片中與霸王(wang)龍展開了(le)對決但之(zhi)后又和(he)霸王(wang)龍一(yi)起襲(xi)擊了(le)主(zhu)角和(he)他(ta)的(de)朋友(you),但在(zai)影(ying)片的(de)最后被主(zhu)角的(de)杯(bei)子炸死。
異特(te)龍也出(chu)現在BBC的(de)電視節(jie)目(mu)《與恐(kong)(kong)龍共舞(wu)》(Walking with Dinosaurs)的(de)第二集與第五集。而《與恐(kong)(kong)龍共舞(wu)》的(de)特(te)別節(jie)目(mu)《異特(te)龍之謎》(Ballad of Big Al),則(ze)是以著名的(de)"大艾爾(er)"作為(wei)主角,敘述(shu)了它的(de)一生。
異特龍也出現在《恐(kong)龍x檔案》中。
另有紀錄片《恐龍革(ge)命》第一季的(de)(de)第二集《異特龍的(de)(de)故(gu)事》講述一只下顎被打(da)斷的(de)(de)異特龍的(de)(de)生活(huo)。
在(zai)CAPCOM于(yu)2000年(nian)推(tui)出的電子游(you)戲《恐龍危(wei)機2》中,異特龍也有多次(ci)登場。
異特龍也出現在IOS的游戲(xi)(侏羅紀世(shi)界)中(zhong)被(bei)錯誤的描述成(cheng)有(you)(you)2個爪(zhua)子(zi)類似霸(ba)王龍實際(ji)上真(zhen)實的異特龍是(shi)有(you)(you)三個爪(zhua)子(zi),不要被(bei)游戲(xi)欺騙了。