懼(ju)(ju)龍(long)是非常著名的(de)北美(mei)洲大型(xing)暴龍(long)類,是其所處時代體型(xing)最大的(de)捕食者。懼(ju)(ju)龍(long)屬下目前有兩(liang)個種(zhong),即模式(shi)種(zhong)強健(jian)懼(ju)(ju)龍(long)和(he)歸入種(zhong)霍氏懼(ju)(ju)龍(long)。懼(ju)(ju)龍(long)的(de)體長約為9米,與(yu)蛇發女(nv)怪(guai)龍(long)和(he)阿爾伯塔(ta)龍(long)相似,但是卻(que)更為健(jian)壯。一些研究認(ren)為懼(ju)(ju)龍(long)的(de)體重可(ke)以(yi)達到3.5噸以(yi)上。
與(yu)霸王(wang)龍(long),特暴龍(long),蛇(she)發(fa)女怪龍(long)和阿爾伯塔(ta)龍(long)一樣,懼龍(long)也有比較(jiao)豐富的(de)標本收藏,因此成為被研(yan)究的(de)最細致的(de)大(da)型暴龍(long)類之一。
懼龍(long)的(de)屬名意為(wei)可(ke)(ke)怕(pa)的(de)蜥蜴,這(zhe)(zhe)一(yi)屬名經常也(ye)被譯作可(ke)(ke)畏龍(long)。模式種(zhong)種(zhong)名的(de)含義(yi)為(wei)強壯(zhuang)的(de)。相比于同體長的(de)阿爾伯塔(ta)龍(long)亞(ya)科(ke)(ke),懼龍(long)確實更(geng)為(wei)健壯(zhuang),頭骨也(ye)顯得更(geng)加厚(hou)實。歸入(ru)種(zhong)種(zhong)名是(shi)為(wei)了(le)紀念古(gu)(gu)生(sheng)物(wu)學(xue)家杰克.霍納在(zai)雙(shuang)麥迪遜(xun)組(zu)的(de)野(ye)外(wai)工作,以及霍納本人對(dui)恐龍(long)古(gu)(gu)生(sheng)物(wu)學(xue)做(zuo)出的(de)杰出貢獻(xian)。這(zhe)(zhe)里(li)順(shun)帶說一(yi)下(xia),杰克.霍納曾是(shi)《侏(zhu)羅紀公園》的(de)科(ke)(ke)學(xue)顧問,而在(zai)重(zhong)啟的(de)《侏(zhu)羅紀世(shi)界》中,劇組(zu)也(ye)在(zai)影(ying)片(pian)中致敬了(le)他(ta),讓他(ta)客(ke)串了(le)一(yi)下(xia)(歐文(wen)第一(yi)次出場訓練伶盜龍(long)的(de)時候)。霍納在(zai)TED上(shang)還有一(yi)個著名的(de)演(yan)講叫《恐龍(long)也(ye)變形(xing)》,主要講述的(de)是(shi)過去古(gu)(gu)生(sheng)物(wu)學(xue)研(yan)究中把(ba)同一(yi)物(wu)種(zhong)幼年個體當成新種(zhong)重(zhong)新命(ming)名的(de)問題,以及他(ta)在(zai)解決這(zhe)(zhe)方面問題上(shang)所做(zuo)的(de)努力。
懼(ju)龍(long)(long)(long)兩(liang)側(ce)的(de)前頜(he)骨(gu)(gu)(gu)鼻(bi)骨(gu)(gu)(gu)突(tu)(tu)緊緊的(de)貼在(zai)一(yi)(yi)起(qi),將兩(liang)側(ce)鼻(bi)骨(gu)(gu)(gu)的(de)前緣(yuan)(yuan)分(fen)(fen)開(kai)。在(zai)蛇(she)(she)發(fa)女(nv)怪(guai)龍(long)(long)(long)中,鼻(bi)骨(gu)(gu)(gu)具有一(yi)(yi)內(nei)側(ce)突(tu)(tu),將前頜(he)骨(gu)(gu)(gu)鼻(bi)骨(gu)(gu)(gu)突(tu)(tu)的(de)后(hou)端(duan)分(fen)(fen)開(kai)。上(shang)(shang)頜(he)骨(gu)(gu)(gu)的(de)外(wai)側(ce)緣(yuan)(yuan)具有兩(liang)排略呈平(ping)行排列的(de)滋(zi)養孔(kong)。懼(ju)龍(long)(long)(long)的(de)淚骨(gu)(gu)(gu)與上(shang)(shang)頜(he)骨(gu)(gu)(gu)的(de)關(guan)節(jie)(jie)(jie)與阿爾伯塔龍(long)(long)(long)類(lei)似,但是在(zai)懼(ju)龍(long)(long)(long)的(de)成年(nian)個(ge)體中,兩(liang)者(zhe)的(de)關(guan)節(jie)(jie)(jie)不(bu)會被鼻(bi)骨(gu)(gu)(gu)分(fen)(fen)開(kai)。懼(ju)龍(long)(long)(long)的(de)鼻(bi)骨(gu)(gu)(gu)在(zai)鼻(bi)骨(gu)(gu)(gu)-淚骨(gu)(gu)(gu)關(guan)節(jie)(jie)(jie)點之后(hou)急劇的(de)收縮,不(bu)同于蛇(she)(she)發(fa)女(nv)怪(guai)龍(long)(long)(long)和阿爾伯塔龍(long)(long)(long),它們的(de)鼻(bi)骨(gu)(gu)(gu)在(zai)這(zhe)一(yi)(yi)關(guan)節(jie)(jie)(jie)點以后(hou)內(nei)外(wai)側(ce)擴展。鼻(bi)骨(gu)(gu)(gu)的(de)腹(fu)外(wai)側(ce)緣(yuan)(yuan)具有一(yi)(yi)條溝與上(shang)(shang)頜(he)骨(gu)(gu)(gu),淚骨(gu)(gu)(gu)和前額骨(gu)(gu)(gu)相(xiang)關(guan)節(jie)(jie)(jie),在(zai)成年(nian)的(de)懼(ju)龍(long)(long)(long)中,這(zhe)條溝被一(yi)(yi)道脊分(fen)(fen)開(kai),而在(zai)蛇(she)(she)發(fa)女(nv)怪(guai)龍(long)(long)(long)和阿爾伯塔龍(long)(long)(long)中是連續的(de)。在(zai)蛇(she)(she)發(fa)女(nv)怪(guai)龍(long)(long)(long)的(de)鼻(bi)骨(gu)(gu)(gu)上(shang)(shang),這(zhe)條溝的(de)后(hou)端(duan)具有一(yi)(yi)指手指狀突(tu)(tu)起(qi)與淚骨(gu)(gu)(gu)的(de)前邊(bian)緣(yuan)(yuan)關(guan)節(jie)(jie)(jie),而這(zhe)一(yi)(yi)突(tu)(tu)起(qi)在(zai)懼(ju)龍(long)(long)(long)中不(bu)存在(zai)。
蛇(she)(she)發(fa)(fa)(fa)女怪龍(long)(long)(long)(long)和阿爾(er)(er)伯(bo)塔(ta)龍(long)(long)(long)(long)的(de)(de)淚骨(gu)(gu)(gu)的(de)(de)背(bei)外側面(mian)具有一發(fa)(fa)(fa)達(da)(da)的(de)(de)骨(gu)(gu)(gu)質(zhi)角,而懼龍(long)(long)(long)(long)的(de)(de)成年個體的(de)(de)淚骨(gu)(gu)(gu)具有一延長的(de)(de)脊。淚骨(gu)(gu)(gu)的(de)(de)后背(bei)側角的(de)(de)氣(qi)孔(kong)在蛇(she)(she)發(fa)(fa)(fa)女怪龍(long)(long)(long)(long)和阿爾(er)(er)伯(bo)塔(ta)龍(long)(long)(long)(long)中比較發(fa)(fa)(fa)達(da)(da),而在懼龍(long)(long)(long)(long)中比較小且呈三角形。在蛇(she)(she)發(fa)(fa)(fa)女怪龍(long)(long)(long)(long)和阿爾(er)(er)伯(bo)塔(ta)龍(long)(long)(long)(long)中,淚骨(gu)(gu)(gu)的(de)(de)氣(qi)孔(kong)之間由較短(duan)的(de)(de)骨(gu)(gu)(gu)質(zhi)分(fen)隔(ge)(ge)隔(ge)(ge)開(kai),而在懼龍(long)(long)(long)(long)中,這(zhe)一骨(gu)(gu)(gu)質(zhi)分(fen)隔(ge)(ge)非常發(fa)(fa)(fa)達(da)(da),甚(shen)至比氣(qi)孔(kong)還要(yao)大。與(yu)蛇(she)(she)發(fa)(fa)(fa)女怪龍(long)(long)(long)(long)相比,懼龍(long)(long)(long)(long)的(de)(de)前(qian)額(e)骨(gu)(gu)(gu)要(yao)更加(jia)狹長,其前(qian)端一直延伸至額(e)骨(gu)(gu)(gu)前(qian)邊緣(yuan)的(de)(de)前(qian)面(mian),而蛇(she)(she)發(fa)(fa)(fa)女怪龍(long)(long)(long)(long)的(de)(de)前(qian)額(e)骨(gu)(gu)(gu)最多延伸至與(yu)額(e)骨(gu)(gu)(gu)前(qian)邊緣(yuan)同(tong)一位置(zhi)。
懼(ju)龍(long)(long)(long)(long)額骨(gu)的后(hou)四分之一(yi)隆起(qi)參與(yu)(yu)到(dao)矢狀脊的形成中(zhong),因此它的矢狀脊比蛇(she)(she)(she)發(fa)女(nv)(nv)怪龍(long)(long)(long)(long)和(he)(he)(he)阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)的要(yao)更高聳。懼(ju)龍(long)(long)(long)(long)的頂骨(gu)頸(jing)背(bei)脊較(jiao)(jiao)阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)和(he)(he)(he)蛇(she)(she)(she)發(fa)女(nv)(nv)怪龍(long)(long)(long)(long)的低矮,但是(shi)更寬(kuan)。懼(ju)龍(long)(long)(long)(long)眶后(hou)骨(gu)上(shang)(shang)的骨(gu)質結(jie)節明顯(xian)(xian)比阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)和(he)(he)(he)蛇(she)(she)(she)發(fa)女(nv)(nv)怪龍(long)(long)(long)(long)的發(fa)達(da)。位于顴(quan)骨(gu)上(shang)(shang),眶前窩(wo)后(hou)腹(fu)側(ce)角(jiao)上(shang)(shang)的氣(qi)孔(kong)在蛇(she)(she)(she)發(fa)女(nv)(nv)怪龍(long)(long)(long)(long)和(he)(he)(he)阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)中(zhong)較(jiao)(jiao)為發(fa)達(da),而在懼(ju)龍(long)(long)(long)(long)中(zhong)比較(jiao)(jiao)小(xiao)。懼(ju)龍(long)(long)(long)(long)的顴(quan)骨(gu)具有(you)前后(hou)向變短(duan)但背(bei)腹(fu)向加深(shen)的角(jiao)狀突,這一(yi)點與(yu)(yu)阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)和(he)(he)(he)蛇(she)(she)(she)發(fa)女(nv)(nv)怪龍(long)(long)(long)(long)不同。顴(quan)骨(gu)位于眼(yan)眶下(xia)部分的背(bei)腹(fu)向深(shen)度較(jiao)(jiao)阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)和(he)(he)(he)蛇(she)(she)(she)發(fa)女(nv)(nv)怪龍(long)(long)(long)(long)有(you)所減小(xiao),但是(shi)內外側(ce)寬(kuan)度有(you)明顯(xian)(xian)的加厚(hou)。方顴(quan)骨(gu)與(yu)(yu)鱗骨(gu)的關節面在前后(hou)向延長,與(yu)(yu)阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)亞(ya)科的成員有(you)明顯(xian)(xian)區別。基蝶骨(gu)竇較(jiao)(jiao)淺(qian)較(jiao)(jiao)寬(kuan),與(yu)(yu)多數暴龍(long)(long)(long)(long)亞(ya)科相似,不同于阿(a)(a)爾(er)伯(bo)(bo)(bo)塔(ta)(ta)(ta)龍(long)(long)(long)(long)亞(ya)科。
霍氏(shi)懼(ju)龍(long)(long)與強健懼(ju)龍(long)(long)的(de)(de)(de)區(qu)別包括(kuo)以下特征組合:上頜(he)(he)骨(gu)的(de)(de)(de)第(di)一(yi)個齒間(jian)板比較小。齒骨(gu)向外(wai)側拱起(qi)。前頜(he)(he)竇終止于(yu)第(di)3和第(di)4齒槽之(zhi)間(jian)。內鼻(bi)孔的(de)(de)(de)前邊緣(yuan)位(wei)于(yu)上頜(he)(he)骨(gu)第(di)7個齒槽的(de)(de)(de)位(wei)置。淚(lei)骨(gu)的(de)(de)(de)背面膨(peng)大,但是(shi)內側面沒有(you)膨(peng)大。淚(lei)骨(gu)降支(zhi)內側的(de)(de)(de)氣孔不(bu)如強健懼(ju)龍(long)(long)的(de)(de)(de)發達。淚(lei)骨(gu)構成眼(yan)眶邊緣(yuan)的(de)(de)(de)上半部分具有(you)明(ming)顯(xian)的(de)(de)(de)凹陷。位(wei)于(yu)額骨(gu)上的(de)(de)(de)上顳窩前邊緣(yuan)為曲線,強健懼(ju)龍(long)(long)中是(shi)直線。頂骨(gu)的(de)(de)(de)后外(wai)側突的(de)(de)(de)基部被頂骨(gu)的(de)(de)(de)鱗骨(gu)關節突覆蓋。鼓室脊延伸至前耳(er)骨(gu)上。方顴骨(gu)的(de)(de)(de)外(wai)側面具有(you)一(yi)明(ming)顯(xian)的(de)(de)(de)穿孔。
懼(ju)龍(long)的化石標本也非常(chang)多,有(you)一(yi)(yi)些甚(shen)至沒有(you)經過正式的發(fa)表(biao)(biao)描(miao)述。以下先列出強健懼(ju)龍(long)的一(yi)(yi)些已發(fa)表(biao)(biao)的標本。
強健懼龍的正型(xing)標(biao)本在(zai)發現之初被(bei)(bei)當作是蛇發女(nv)怪龍的的標(biao)本。在(zai)戴爾.羅(luo)素1970年的文章系(xi)統描述和(he)比較(jiao)加(jia)拿大(da)地(di)區的暴(bao)龍類時才(cai)被(bei)(bei)定為新屬(shu)種(zhong)。
正型標本:NMC 8506保(bao)存了頭骨(gu)(gu),肩帶骨(gu)(gu)骼(ge),前(qian)肢,腰帶和股(gu)骨(gu)(gu),大多(duo)數的頸椎(zhui),背(bei)椎(zhui)和薦(jian)椎(zhui),還(huan)有前(qian)11節(jie)尾椎(zhui)。
歸(gui)入(ru)標本:AMNH 5438保(bao)存(cun)了薦椎,背椎和尾椎,腰帶,右側股骨(gu),左(zuo)側脛骨(gu)和第(di)二(er)跖(zhi)骨(gu)。
歸入標(biao)本:NMC 350保存了左側后肢。
歸入標本:AMNH 5346為一件(jian)上頜骨。
歸入(ru)標本(ben):UA 11右側股骨(gu)和(he)第(di)四跖骨(gu)。
歸(gui)入標(biao)本(ben):NMC 11594保存(cun)了不完整的,風(feng)化較嚴重的頭(tou)骨。
歸入標本(ben):BMNH R4863保存了前(qian)頜骨(gu),上頜骨(gu)和齒(chi)骨(gu)。
歸入標本:RTMP 2001.36.1一(yi)件幾乎完整的骨架。
歸(gui)入標(biao)本:FMNH PR308是(shi)一件保(bao)存質量很(hen)好的(de)標(biao)本,保(bao)存了頭(tou)骨(gu)和大多(duo)數頭(tou)后骨(gu)骼。起(qi)初(chu)被認為時阿爾(er)伯塔龍。后在(zai)托馬斯.卡爾(er)1999年(nian)的(de)研究中(zhong)歸(gui)入到(dao)懼龍模式種。
歸入標(biao)本:AMNH 5434曾經(jing)被歸入到蛇發女怪龍模式(shi)種(zhong),保存(cun)了幾乎完整(zheng)的(de)頭骨。頭后(hou)骨骼缺乏尾(wei)椎和后(hou)肢(zhi),其它部位幾乎完整(zheng)。在托(tuo)馬斯.卡爾1999年的(de)工(gong)作中歸入到懼龍模式(shi)種(zhong)。
歸入標本:TMP 94.218.1為一個幼年個體。托馬斯.卡爾1999年的工作中(zhong)列出。
歸(gui)入標(biao)本:NMC 841為一成年(nian)個體。托馬斯(si).卡爾1999年(nian)的工作中(zhong)列(lie)出。
歸入標本:TMP 82.13.1為一個(ge)成年個(ge)體。托馬斯.卡爾1999年的(de)工作中列出(chu)。
歸入標本:TMP 83.38.1為一個成年個體。托馬(ma)斯.卡(ka)爾1999年的工作中列出。
歸(gui)入(ru)標本:TMP 85.62.1為(wei)一個(ge)成(cheng)年(nian)個(ge)體。托馬(ma)斯.卡爾1999年(nian)的工作中列出。
歸入標本(ben):TMP 1994.143.0001屬(shu)于一只約5米長(chang)的年(nian)輕懼龍。頭(tou)骨幾乎完整,但頭(tou)后骨骼風化嚴重(zhong)。
下面列出霍(huo)氏懼龍(long)的主要標本(ben):
正型標本:MOR 590保(bao)存(cun)了完(wan)整(zheng)的頭(tou)骨,部分(fen)保(bao)存(cun)的肩帶和前肢(zhi)以及完(wan)整(zheng)的后肢(zhi)。
歸入(ru)標本:MOR 1130保存了(le)一(yi)個不完整的頭骨(gu)(gu),部分保存的中軸骨(gu)(gu)格(ge)序列,部分保存的腰(yao)帶骨(gu)(gu)骼和后肢(zhi)。
歸入標本:MOR 553S/7.19.0.97一(yi)塊齒骨,屬于一(yi)個小幼體(ti)。
歸入標本(ben):AMNH FARB 5477包括一塊上頜(he)骨(gu)(gu),部(bu)分保存(cun)的眶后骨(gu)(gu)和頂骨(gu)(gu)。
歸入標(biao)本:MOR 3068部(bu)分保存的(de)下(xia)頜。
歸(gui)入標本:MOR 553D.9.19.91左側的外(wai)翼骨。
歸入標本(ben):MOR 553E.7.6.91.196,右(you)側的外(wai)翼骨。
除(chu)此(ci)之外,還有一些被鑒(jian)定(ding)(ding)屬(shu)于(yu)懼(ju)龍(long)屬(shu),但是沒有明確(que)定(ding)(ding)種的(de)標本。它(ta)們有可(ke)能屬(shu)于(yu)已知(zhi)的(de)兩種懼(ju)龍(long),也有可(ke)能是第三種。
目前主要的暴龍(long)(long)類或虛骨龍(long)(long)類系(xi)統發(fa)育分析都支持懼龍(long)(long)屬(shu)于暴龍(long)(long)亞科,且(qie)與霸王龍(long)(long)和特暴龍(long)(long)(有時會包括(kuo)諸城暴龍(long)(long))具有非(fei)常近(jin)的親(qin)緣關系(xi)。而排(pai)除掉(diao)亞洲的暴龍(long)(long)類以后,懼龍(long)(long)是北(bei)美大(da)陸上與霸王龍(long)(long)親(qin)緣關系(xi)最近(jin)的成(cheng)員。
懼龍的頭(tou)骨長度可以超過1米。戴(dai)爾.羅素(su)對于懼龍的體型估計是(shi)體長8-9米。而體重估計一般在2.5噸(dun)左右,但是(shi)具有較(jiao)大的波動(dong)范(fan)圍(1.8至3.8噸(dun))。2014年的一項研究估計值(zhi)為3.6噸(dun)。
2017年的(de)(de)(de)(de)(de)一(yi)項研究參考現(xian)生的(de)(de)(de)(de)(de)主(zhu)龍(long)類(lei)復(fu)原了懼(ju)龍(long)的(de)(de)(de)(de)(de)面(mian)(mian)部軟組織(zhi)。研究人員(yuan)認為懼(ju)龍(long)的(de)(de)(de)(de)(de)面(mian)(mian)部具有種(zhong)類(lei)豐(feng)富(fu)的(de)(de)(de)(de)(de)表皮組織(zhi),除了鱗(lin)片以外(wai),在它的(de)(de)(de)(de)(de)前頜(he)骨(gu),鼻骨(gu)和(he)淚骨(gu)還(huan)有顴骨(gu),以及齒骨(gu)的(de)(de)(de)(de)(de)吻端(duan)應該會(hui)覆蓋一(yi)些(xie)骨(gu)質(zhi)的(de)(de)(de)(de)(de)小突起,而(er)眶后(hou)骨(gu)角的(de)(de)(de)(de)(de)表面(mian)(mian)應該會(hui)覆蓋有非常厚的(de)(de)(de)(de)(de)角質(zhi)層(ceng)。除此之外(wai),懼(ju)龍(long)的(de)(de)(de)(de)(de)吻端(duan)還(huan)具有豐(feng)富(fu)的(de)(de)(de)(de)(de)神經陷窩。懼(ju)龍(long)的(de)(de)(de)(de)(de)吻端(duan)可能(neng)與現(xian)生鱷魚的(de)(de)(de)(de)(de)吻端(duan)具有相似的(de)(de)(de)(de)(de)功能(neng),包括(kuo)捕獵,感(gan)受溫度(du)和(he)不同(tong)物體的(de)(de)(de)(de)(de)材質(zhi),以及同(tong)類(lei)之間的(de)(de)(de)(de)(de)社會(hui)性行(xing)為。吻部表面(mian)(mian)覆蓋的(de)(de)(de)(de)(de)骨(gu)質(zhi)小突起可能(neng)能(neng)夠起到對感(gan)受系統保護的(de)(de)(de)(de)(de)作用。
關于(yu)懼(ju)龍(long)(long)群(qun)居性(xing)的(de)(de)(de)(de)(de)(de)證據(ju)在(zai)雙(shuang)麥迪遜組被找到。在(zai)一個(ge)產出(chu)懼(ju)龍(long)(long)化(hua)(hua)石的(de)(de)(de)(de)(de)(de)骨床中(zhong),至少有(you)(you)屬于(yu)三(san)個(ge)不同(tong)個(ge)體(ti)的(de)(de)(de)(de)(de)(de)懼(ju)龍(long)(long)骨骼被發(fa)現(xian)。除(chu)此(ci)之外,這(zhe)里還發(fa)現(xian)了5具(ju)鴨嘴龍(long)(long)類的(de)(de)(de)(de)(de)(de)化(hua)(hua)石。這(zhe)些懼(ju)龍(long)(long)骨骼中(zhong),至少有(you)(you)一只大型的(de)(de)(de)(de)(de)(de)成(cheng)年個(ge)體(ti),一只中(zhong)等大小的(de)(de)(de)(de)(de)(de)個(ge)體(ti),還有(you)(you)一只小幼體(ti)。依據(ju)對于(yu)化(hua)(hua)石點的(de)(de)(de)(de)(de)(de)埋藏學分(fen)析(xi),這(zhe)些尸體(ti)不像是(shi)被從別的(de)(de)(de)(de)(de)(de)地方沖(chong)下來的(de)(de)(de)(de)(de)(de),而(er)像是(shi)在(zai)較短(duan)的(de)(de)(de)(de)(de)(de)時間內被同(tong)時埋藏的(de)(de)(de)(de)(de)(de)。5具(ju)鴨嘴龍(long)(long)的(de)(de)(de)(de)(de)(de)骨骼上都有(you)(you)暴龍(long)(long)類的(de)(de)(de)(de)(de)(de)齒痕,顯(xian)示這(zhe)群(qun)懼(ju)龍(long)(long)在(zai)死前可能進食過這(zhe)些尸體(ti)。菲利普.柯瑞認為這(zhe)批化(hua)(hua)石是(shi)懼(ju)龍(long)(long)群(qun)居性(xing)行為的(de)(de)(de)(de)(de)(de)證據(ju),并且推測(ce)它(ta)們(men)會成(cheng)群(qun)出(chu)動協同(tong)捕(bu)獵。其他(ta)古生(sheng)物學家則對此(ci)持懷疑態(tai)度。
同(tong)(tong)類(lei)相(xiang)殘在(zai)(zai)(zai)現(xian)(xian)生(sheng)的(de)(de)(de)大(da)型(xing)(xing)(xing)食肉動(dong)物中(zhong)(zhong)是一種(zhong)常見的(de)(de)(de)現(xian)(xian)象(xiang)。化石證據顯(xian)示這種(zhong)現(xian)(xian)象(xiang)在(zai)(zai)(zai)獸(shou)腳(jiao)類(lei)恐龍(long)中(zhong)(zhong)也比較常見。一件年(nian)輕的(de)(de)(de)懼龍(long)標(biao)本(ben)的(de)(de)(de)面部留有(you)暴龍(long)類(lei)的(de)(de)(de)咬痕(hen)。咬痕(hen)有(you)愈(yu)合(he)的(de)(de)(de)痕(hen)跡(ji),顯(xian)示這只動(dong)物在(zai)(zai)(zai)襲擊中(zhong)(zhong)活(huo)了下來。另外一件成年(nian)的(de)(de)(de)懼龍(long)標(biao)本(ben)也有(you)大(da)型(xing)(xing)(xing)暴龍(long)類(lei)的(de)(de)(de)咬痕(hen)。這些證據顯(xian)示,大(da)型(xing)(xing)(xing)暴龍(long)類(lei)的(de)(de)(de)同(tong)(tong)類(lei)相(xiang)殘行為(wei)(wei)不止局限于(yu)傷害小(xiao)體(ti)型(xing)(xing)(xing)的(de)(de)(de)個體(ti),同(tong)(tong)類(lei)間(jian)(jian)的(de)(de)(de)打斗(dou)在(zai)(zai)(zai)大(da)型(xing)(xing)(xing)個體(ti)間(jian)(jian)也存在(zai)(zai)(zai)。其(qi)它的(de)(de)(de)獸(shou)腳(jiao)類(lei)如大(da)型(xing)(xing)(xing)暴龍(long)類(lei)蛇發女怪(guai)龍(long)和霸王(wang)龍(long),還有(you)大(da)型(xing)(xing)(xing)異(yi)特龍(long)類(lei)中(zhong)(zhong)華盜(dao)龍(long),以及(ji)小(xiao)體(ti)型(xing)(xing)(xing)的(de)(de)(de)馳龍(long)類(lei)蜥(xi)鳥盜(dao)龍(long)的(de)(de)(de)頭骨上也會有(you)被(bei)其(qi)它動(dong)物咬過的(de)(de)(de)痕(hen)跡(ji)。菲利(li)普(pu).柯(ke)瑞認為(wei)(wei),獸(shou)腳(jiao)類(lei)恐龍(long)之間(jian)(jian)的(de)(de)(de)攻擊性(xing)行為(wei)(wei)主(zhu)要是由于(yu)種(zhong)間(jian)(jian)競爭和領域保護性(xing)行為(wei)(wei)導(dao)致的(de)(de)(de)。
大(da)(da)型(xing)暴(bao)龍(long)(long)(long)類在(zai)個體發育過(guo)程中(zhong)的(de)體重(zhong)增加符合“S”型(xing)曲(qu)線。懼龍(long)(long)(long)的(de)最(zui)大(da)(da)生長速(su)度(du)為每(mei)年180千克,大(da)(da)于蛇發女怪(guai)龍(long)(long)(long)和(he)(he)阿(a)爾伯塔龍(long)(long)(long),而(er)這樣的(de)結(jie)果還只是(shi)使用了(le)較低估計的(de)成體體重(zhong)(1.8噸)。使用更大(da)(da)的(de)成體體重(zhong)估計將會(hui)增加最(zui)大(da)(da)生長速(su)率的(de)估計值,但是(shi)并不會(hui)改變(bian)擬合曲(qu)線的(de)整體形狀。懼龍(long)(long)(long)的(de)最(zui)大(da)(da)生長速(su)率遠低于霸王龍(long)(long)(long),且“S”型(xing)曲(qu)線更早(zao)達(da)到漸進平緩。這也表(biao)明(ming),暴(bao)龍(long)(long)(long)類在(zai)大(da)(da)型(xing)化的(de)過(guo)程中(zhong)可(ke)能同時使用了(le)增加最(zui)大(da)(da)生長速(su)度(du)和(he)(he)增加生長時間的(de)策略。
懼龍(long)在(zai)(zai)個(ge)(ge)體發育的(de)(de)(de)(de)過(guo)(guo)程(cheng)中(zhong)(zhong)會經(jing)歷一系列(lie)的(de)(de)(de)(de)形(xing)態(tai)變(bian)(bian)化。最為明顯的(de)(de)(de)(de)一點(dian)是牙(ya)齒數(shu)(shu)量的(de)(de)(de)(de)變(bian)(bian)化。對于霍氏懼龍(long)的(de)(de)(de)(de)研究發現(xian),最年(nian)輕的(de)(de)(de)(de)個(ge)(ge)體的(de)(de)(de)(de)上(shang)頜(he)骨(gu)齒有(you)(you)15個(ge)(ge)(AMNH FARB 5477),而亞(ya)成體的(de)(de)(de)(de)增加到了17個(ge)(ge)((MOR 590),之(zhi)后(hou)成年(nian)個(ge)(ge)體的(de)(de)(de)(de)數(shu)(shu)量又下降到15個(ge)(ge)(MOR 1130)。與上(shang)頜(he)相(xiang)比,齒骨(gu)齒的(de)(de)(de)(de)數(shu)(shu)量在(zai)(zai)個(ge)(ge)體發育中(zhong)(zhong)沒有(you)(you)變(bian)(bian)化。強健(jian)懼龍(long)在(zai)(zai)個(ge)(ge)體發育的(de)(de)(de)(de)過(guo)(guo)程(cheng)中(zhong)(zhong)也存在(zai)(zai)牙(ya)齒數(shu)(shu)量變(bian)(bian)化的(de)(de)(de)(de)現(xian)象。強健(jian)懼龍(long)最年(nian)輕的(de)(de)(de)(de)個(ge)(ge)體(TMP 1994.143.0001)具(ju)有(you)(you)13顆(ke)上(shang)頜(he)骨(gu)齒,更大一點(dian)的(de)(de)(de)(de)亞(ya)成體(AMNH 5346)有(you)(you)15或16顆(ke),而再老(lao)一點(dian)的(de)(de)(de)(de)個(ge)(ge)體會減少到14顆(ke)(NMC 8506)。這種牙(ya)齒數(shu)(shu)量的(de)(de)(de)(de)變(bian)(bian)化在(zai)(zai)霸王(wang)龍(long)中(zhong)(zhong)也得到了證實。這一研究表明個(ge)(ge)體發育過(guo)(guo)程(cheng)中(zhong)(zhong)的(de)(de)(de)(de)牙(ya)齒數(shu)(shu)量先增加再減少的(de)(de)(de)(de)現(xian)象可能廣泛存在(zai)(zai)于暴龍(long)亞(ya)科中(zhong)(zhong)。
對于(yu)霍氏懼龍的研究(jiu)發(fa)(fa)(fa)現(xian),其面(mian)部(bu)紋(wen)飾(shi)(shi)也(ye)(ye)會隨著個(ge)(ge)體(ti)發(fa)(fa)(fa)育(yu)階段的變化而變化,尤其是鼻骨的紋(wen)飾(shi)(shi)會隨著年齡增大而減(jian)弱(ruo)。這種現(xian)象也(ye)(ye)見于(yu)霸(ba)王(wang)龍。對于(yu)角(jiao)龍類和腫頭龍類的研究(jiu)發(fa)(fa)(fa)現(xian),頭部(bu)的裝飾(shi)(shi)也(ye)(ye)會隨著個(ge)(ge)體(ti)發(fa)(fa)(fa)育(yu)而減(jian)弱(ruo)。結合系統發(fa)(fa)(fa)育(yu)框架以及簡約性原(yuan)則(ze)可(ke)以推(tui)測(ce),頭部(bu)裝飾(shi)(shi)隨個(ge)(ge)體(ti)發(fa)(fa)(fa)育(yu)減(jian)弱(ruo)是整個(ge)(ge)恐龍單(dan)系的共近(jin)裔特(te)征。
對于懼龍的(de)(de)(de)種(zhong)群(qun)生(sheng)物學研究發(fa)現,它與霸(ba)王龍,蛇(she)發(fa)女怪龍和阿(a)爾伯塔龍具(ju)有(you)相(xiang)似(si)的(de)(de)(de)存(cun)活(huo)曲線,即(ji)較(jiao)(jiao)低的(de)(de)(de)新生(sheng)個(ge)(ge)體(ti)存(cun)活(huo)率(lv)(lv)(lv),較(jiao)(jiao)高的(de)(de)(de)幼(you)(you)年個(ge)(ge)體(ti)存(cun)活(huo)率(lv)(lv)(lv),以(yi)及(ji)從(cong)中(zhong)(zhong)年期開始死亡率(lv)(lv)(lv)又再一次升高。懼龍以(yi)及(ji)其它大(da)(da)型(xing)(xing)暴龍類(lei)(lei)(lei)的(de)(de)(de)群(qun)居性(xing)行為(wei)可(ke)(ke)能(neng)(neng)能(neng)(neng)夠有(you)效降低年輕個(ge)(ge)體(ti)的(de)(de)(de)死亡率(lv)(lv)(lv)。同時(shi)大(da)(da)型(xing)(xing)暴龍類(lei)(lei)(lei)較(jiao)(jiao)快的(de)(de)(de)生(sheng)長速度(du)(du)(du)也能(neng)(neng)使(shi)它們的(de)(de)(de)幼(you)(you)體(ti)快速度(du)(du)(du)過危(wei)險(xian)期,達到(dao)普通捕食者無法捕食的(de)(de)(de)體(ti)型(xing)(xing)閾(yu)值。而(er)同類(lei)(lei)(lei)相(xiang)殘行為(wei)可(ke)(ke)能(neng)(neng)是死亡率(lv)(lv)(lv)從(cong)中(zhong)(zhong)年時(shi)期開始再度(du)(du)(du)增加的(de)(de)(de)主(zhu)要原(yuan)因。
懼龍(long)(long)的(de)生活范(fan)圍與(yu)蛇發(fa)(fa)女怪龍(long)(long)有(you)(you)所重疊(die)。戴爾.羅素認為懼龍(long)(long)身體更(geng)為龐大,適合(he)捕(bu)食防御(yu)能(neng)力較好的(de)角龍(long)(long)類(lei),而蛇發(fa)(fa)女怪龍(long)(long)的(de)體態較為輕盈,適合(he)捕(bu)食鴨嘴(zui)(zui)龍(long)(long)類(lei)。然而一(yi)(yi)件懼龍(long)(long)標本(ben)的(de)胃容物里發(fa)(fa)現了幼年鴨嘴(zui)(zui)龍(long)(long)類(lei)的(de)殘骸。另(ling)外一(yi)(yi)種可能(neng)是(shi)兩種大型暴龍(long)(long)類(lei)雖然棲息在一(yi)(yi)片(pian)區域,但是(shi)它(ta)們生活的(de)微生境是(shi)不同的(de),因此兩者可能(neng)沒(mei)有(you)(you)太(tai)多的(de)機會(hui)見面打架。
懼(ju)(ju)(ju)龍(long)(long)(long)登場于(yu)BBC的紀錄片《恐(kong)龍(long)(long)(long)星球》。在(zai)片中(zhong)(zhong),懼(ju)(ju)(ju)龍(long)(long)(long)被描述為群居的巨型殺手,依靠團(tuan)隊(dui)合作捕(bu)食落單的開角(jiao)龍(long)(long)(long),同時也會埋伏在(zai)尖角(jiao)龍(long)(long)(long)群遷徙的必經之(zhi)路上,伺機對獵物展開屠殺。懼(ju)(ju)(ju)龍(long)(long)(long)還登場于(yu)Discovery的同名紀錄片《恐(kong)龍(long)(long)(long)星球》中(zhong)(zhong)。片中(zhong)(zhong)的懼(ju)(ju)(ju)龍(long)(long)(long)會團(tuan)隊(dui)合作捕(bu)食慈母龍(long)(long)(long),同時影(ying)片中(zhong)(zhong)還將懼(ju)(ju)(ju)龍(long)(long)(long)描述為霸王(wang)龍(long)(long)(long)的祖先。這種描述是(shi)不嚴謹(jin)的,但依據(ju)現階段的大多數系統發(fa)育分(fen)析,如果除去亞(ya)洲的諸城暴(bao)龍(long)(long)(long)和(he)特暴(bao)龍(long)(long)(long),懼(ju)(ju)(ju)龍(long)(long)(long)確實是(shi)北(bei)美大型暴(bao)龍(long)(long)(long)類中(zhong)(zhong)和(he)霸王(wang)龍(long)(long)(long)親緣關系最近的成(cheng)員。
在暴龍(long)(long)科中,達斯布雷龍(long)(long)與特暴龍(long)(long)、暴龍(long)(long)及分支龍(long)(long)同屬于暴龍(long)(long)亞科。暴龍(long)(long)亞科的(de)(de)(de)物種都是較接近暴龍(long)(long),而(er)較不(bu)類(lei)似艾(ai)伯(bo)塔龍(long)(long),特征都是粗壯的(de)(de)(de)體型、比例上較大的(de)(de)(de)頭顱(lu)骨、以(yi)及較長的(de)(de)(de)股骨。
達(da)(da)(da)斯(si)布(bu)雷(lei)(lei)龍(long)通常被(bei)認為是暴龍(long)的(de)近親,或是往暴龍(long)前進演(yan)(yan)化(hua)(hua)的(de)直(zhi)接(jie)祖(zu)先。格里(li)高利·保羅(Gregory S.Paul)曾將強健達(da)(da)(da)斯(si)布(bu)雷(lei)(lei)龍(long)編入暴龍(long)屬中,但這(zhe)個(ge)(ge)(ge)分(fen)(fen)(fen)類(lei)卻一(yi)般不(bu)被(bei)接(jie)受(shou)。很(hen)多學(xue)者認為特暴龍(long)及暴龍(long)是姊(zi)妹分(fen)(fen)(fen)類(lei)單(dan)元,或甚(shen)至(zhi)是同屬,而(er)達(da)(da)(da)斯(si)布(bu)雷(lei)(lei)龍(long)是這(zhe)個(ge)(ge)(ge)演(yan)(yan)化(hua)(hua)支的(de)基礎物種(zhong)。菲力(li)·柯爾(Phil Currie)等(deng)人提出一(yi)個(ge)(ge)(ge)不(bu)同的(de)理論(lun),分(fen)(fen)(fen)支龍(long)與特暴龍(long)這(zhe)兩個(ge)(ge)(ge)亞洲(zhou)屬構成一(yi)個(ge)(ge)(ge)演(yan)(yan)化(hua)(hua)支,而(er)達(da)(da)(da)斯(si)布(bu)雷(lei)(lei)龍(long)較(jiao)接(jie)近這(zhe)個(ge)(ge)(ge)演(yan)(yan)化(hua)(hua)支,而(er)離北(bei)美洲(zhou)的(de)暴龍(long)較(jiao)遠。要(yao)待(dai)所有的(de)達(da)(da)(da)斯(si)布(bu)雷(lei)(lei)龍(long)物種(zhong)被(bei)研究、描(miao)述,才可以(yi)得(de)到較(jiao)清晰的(de)達(da)(da)(da)斯(si)布(bu)雷(lei)(lei)龍(long)分(fen)(fen)(fen)類(lei)關系。
對于現今(jin)的獵食動物而言,達斯布雷龍(long)體(ti)(ti)(ti)型非常巨大(da),相當于一(yi)頭成年(nian)亞洲(zhou)象的大(da)小。成年(nian)的強健懼龍(long)的一(yi)般身長最大(da)可達10米,平均體(ti)(ti)(ti)重估計(ji)約為4噸(dun)(dun),最大(da)個(ge)體(ti)(ti)(ti)可超(chao)過(guo)6噸(dun)(dun)。一(yi)個(ge)懼龍(long)屬的暫時未命(ming)名種超(chao)懼龍(long)(暫時代稱)則可以達到7.5噸(dun)(dun)重。
達斯(si)(si)布(bu)雷(lei)龍(long)(long)(long)有巨大(da)(da)的(de)(de)(de)頭(tou)顱(lu)(lu)骨(gu)(gu),約有1.1米(mi)長。頭(tou)顱(lu)(lu)骨(gu)(gu)的(de)(de)(de)構造(zao)特別(bie)堅固,例如(ru)口鼻(bi)部(bu)上(shang)的(de)(de)(de)鼻(bi)骨(gu)(gu)互相(xiang)愈合,以增加(jia)強度,而頭(tou)骨(gu)(gu)的(de)(de)(de)大(da)(da)型洞孔則可減低重(zhong)量。成年(nian)的(de)(de)(de)達斯(si)(si)布(bu)雷(lei)龍(long)(long)(long)約有60多(duo)顆牙(ya)齒(chi),每只牙(ya)齒(chi)都(dou)(dou)非(fei)(fei)常長而厚(hou)重(zhong)。牙(ya)齒(chi)的(de)(de)(de)橫切面呈橢圓形而非(fei)(fei)短刃形。前上(shang)頜骨(gu)(gu)的(de)(de)(de)牙(ya)齒(chi)卻是呈D型的(de)(de)(de),這(zhe)種異(yi)齒(chi)型在暴龍(long)(long)(long)科中是非(fei)(fei)常普(pu)遍(bian)的(de)(de)(de)。達斯(si)(si)布(bu)雷(lei)龍(long)(long)(long)頭(tou)顱(lu)(lu)骨(gu)(gu)的(de)(de)(de)獨(du)特處在于,上(shang)頜骨(gu)(gu)的(de)(de)(de)表面凹凸不平,以及(ji)眼睛(jing)周圍的(de)(de)(de)淚骨(gu)(gu)、眶后(hou)骨(gu)(gu)及(ji)顴骨(gu)(gu)有明顯的(de)(de)(de)隆起。眼窩呈長橢圓形,介于蛇(she)發女怪龍(long)(long)(long)的(de)(de)(de)圓形及(ji)暴龍(long)(long)(long)的(de)(de)(de)鑰孔形之間。吻(wen)部(bu)很寬,96厘米(mi)頭(tou)骨(gu)(gu)吻(wen)寬35厘米(mi),最大(da)(da)頭(tou)骨(gu)(gu)(超懼龍(long)(long)(long)唯一和最大(da)(da)個體)137厘米(mi)吻(wen)寬可能達到50厘米(mi),吻(wen)寬比(bi)同體型的(de)(de)(de)霸王(wang)龍(long)(long)(long)都(dou)(dou)寬不少。
與(yu)其他的暴(bao)龍(long)科(ke)都有(you)著相似的體型(xing),都是由呈S型(xing)的頸部支撐著沉(chen)重的頭部。它的前肢(zhi)非常的短(duan)小,只有(you)二(er)指,不(bu)過在(zai)暴(bao)龍(long)亞科(ke)中,達斯布(bu)(bu)雷龍(long)的前肢(zhi)與(yu)身體比例(li)是目前發現最(zui)長(chang)(chang)的。達斯布(bu)(bu)雷龍(long)具有(you)兩個(ge)巨大而長(chang)(chang)后肢(zhi),上(shang)有(you)四趾,第(di)一(yi)趾為反爪,無法接觸地面。達斯布(bu)(bu)雷龍(long)具有(you)長(chang)(chang)及重的尾巴,可平衡頭部與(yu)胸(xiong)部,使(shi)重心位(wei)在(zai)臀部上(shang)。
目前科(ke)學家表明,同體(ti)型(xing)的情況下,達斯布雷龍攻擊力不亞于霸王龍。
達斯布(bu)雷龍(屬名:Daspletosaurus)又名懼龍。是暴龍科下的一屬恐龍。它們極少(shao)群居,大(da)(da)多是零(ling)(ling)零(ling)(ling)散散的分布(bu)在(zai)(zai)(zai)各處。只有(you)(you)在(zai)(zai)(zai)遷移或遠行時才有(you)(you)例外(wai)。它們有(you)(you)時住在(zai)(zai)(zai)山林(lin)中的洞穴里、有(you)(you)時住在(zai)(zai)(zai)濃密的叢林(lin)中,它們是以突襲的方式獵捕(bu)食物。它用(yong)那粗大(da)(da)有(you)(you)力的尾巴橫(heng)掃(sao)獵物,將其一口(kou)咬住。
達斯布(bu)雷(lei)龍的(de)棲息環(huan)境很廣,主要分(fen)布(bu)在樹(shu)林、山(shan)谷、溪(xi)邊(bian),它(ta)不喜歡在山(shan)上,因為(wei)這樣(yang)不善于奔跑。
繁(fan)殖方式跟別的恐(kong)龍(long)一樣,也是(shi)通過產(chan)卵方式繁(fan)殖。
強健達斯(si)布雷龍(long)(Daspletosaurus torosus)的(de)(de)(de)模(mo)式標(biao)(biao)本(ben)(ben)是(shi)一個(ge)完(wan)(wan)整(zheng)(zheng)性約(yue)75%的(de)(de)(de)骨(gu)(gu)骼,包括了(le)(le)完(wan)(wan)整(zheng)(zheng)的(de)(de)(de)頭顱骨(gu)(gu)、幾乎完(wan)(wan)整(zheng)(zheng)的(de)(de)(de)頸(jing)椎(zhui)、完(wan)(wan)整(zheng)(zheng)的(de)(de)(de)脊椎(zhui)骨(gu)(gu)、前(qian)(qian)11節尾椎(zhui)、肩膀、一個(ge)完(wan)(wan)整(zheng)(zheng)的(de)(de)(de)前(qian)(qian)肢、骨(gu)(gu)盆(pen)及兩根股骨(gu)(gu)。這(zhe)些(xie)化石(shi)是(shi)于1921年(nian)由(you)(you)查爾(er)斯(si)·斯(si)騰伯(bo)格(Charles Mortram Sternberg)所發(fa)現,他最(zui)初認為這(zhe)些(xie)化石(shi)屬(shu)于蛇發(fa)女怪龍(long)的(de)(de)(de)一個(ge)新(xin)(xin)種(zhong)(zhong)。但是(shi),這(zhe)些(xie)標(biao)(biao)本(ben)(ben)要直到1970年(nian)才由(you)(you)戴(dai)爾(er)·羅素(Dale Russell)完(wan)(wan)全的(de)(de)(de)描述,并建立新(xin)(xin)的(de)(de)(de)達斯(si)布雷龍(long)屬(shu)。達斯(si)布雷龍(long)的(de)(de)(de)學名是(shi)由(you)(you)古(gu)希(xi)臘文的(de)(de)(de)"δασπλητo-"(意即(ji)"懼怕")及"σαυρο?"(意即(ji)"蜥蜴")組合而來(lai)。種(zhong)(zhong)名的(de)(de)(de)torosus是(shi)一拉丁文,意指"強壯(zhuang)"或"結(jie)實"。除了(le)(le)模(mo)式標(biao)(biao)本(ben)(ben),在2001年(nian)發(fa)現一個(ge)完(wan)(wan)整(zheng)(zheng)的(de)(de)(de)達斯(si)布雷龍(long)骨(gu)(gu)骼標(biao)(biao)本(ben)(ben)。這(zhe)兩個(ge)標(biao)(biao)本(ben)(ben)都(dou)是(shi)來(lai)自加拿(na)大的(de)(de)(de)阿爾(er)伯(bo)塔省,發(fa)現于朱迪斯(si)河群中的(de)(de)(de)奧爾(er)德曼組。另一個(ge)年(nian)代較晚的(de)(de)(de)馬蹄峽谷(gu)組發(fa)現的(de)(de)(de)標(biao)(biao)本(ben)(ben),被重新(xin)(xin)歸類于艾伯(bo)塔龍(long)。奧爾(er)德曼組是(shi)在上白(bai)堊紀的(de)(de)(de)坎帕階中期形成(cheng)的(de)(de)(de),距今約(yue)有7700萬(wan)-7600萬(wan)年(nian)前(qian)(qian)。
在建(jian)立(li)(li)強健達斯(si)(si)(si)布雷(lei)龍(long)(long)(long)的(de)(de)(de)正模(mo)標(biao)本(ben)時,羅素(su)將由巴納姆·布郎(Barnum Brown)于1913年(nian)(nian)所挖掘的(de)(de)(de)標(biao)本(ben),建(jian)立(li)(li)為(wei)(wei)強健達斯(si)(si)(si)布雷(lei)龍(long)(long)(long)的(de)(de)(de)副模(mo)標(biao)本(ben)。這個(ge)標(biao)本(ben)包(bao)含(han)了一個(ge)骨(gu)(gu)(gu)盆(pen)、部份后肢、及一些相連的(de)(de)(de)脊椎,是發(fa)現(xian)于阿(a)爾(er)伯塔省(sheng)的(de)(de)(de)奧爾(er)德曼(man)組的(de)(de)(de)較(jiao)上層。這個(ge)較(jiao)上層后被(bei)更名為(wei)(wei)恐(kong)龍(long)(long)(long)公(gong)園(yuan)組,屬(shu)于坎(kan)帕階(jie)晚(wan)期,距今7600萬(wan)-7400萬(wan)年(nian)(nian)前。于1914年(nian)(nian),布郎從(cong)同一地層發(fa)現(xian)接近(jin)完(wan)整的(de)(de)(de)骨(gu)(gu)(gu)骼及頭顱骨(gu)(gu)(gu),并于40年(nian)(nian)后由美國(guo)自然歷史博物(wu)(wu)館(guan)售予芝加(jia)哥(ge)的(de)(de)(de)菲爾(er)德自然歷史博物(wu)(wu)館(guan)。這顱骨(gu)(gu)(gu)目前在芝加(jia)哥(ge)菲爾(er)德博物(wu)(wu)館(guan)展出中(zhong)(zhong),并多(duo)年(nian)(nian)以來都(dou)(dou)被(bei)歸(gui)類為(wei)(wei)是"Albertosaurus libratus"。但在發(fa)現(xian)幾個(ge)頭顱骨(gu)(gu)(gu)特征(zheng)(包(bao)括大(da)部份的(de)(de)(de)牙齒)被(bei)石(shi)膏隱藏多(duo)年(nian)(nian)后,這個(ge)標(biao)本(ben)才被(bei)重置在達斯(si)(si)(si)布雷(lei)龍(long)(long)(long)屬(shu)中(zhong)(zhong)。在恐(kong)龍(long)(long)(long)公(gong)園(yuan)組一共發(fa)現(xian)了八具標(biao)本(ben),大(da)部份都(dou)(dou)是在恐(kong)龍(long)(long)(long)省(sheng)立(li)(li)公(gong)園(yuan)的(de)(de)(de)范圍(wei)內(nei)。菲力(li)·柯爾(er)(Phil Currie)發(fa)現(xian)恐(kong)龍(long)(long)(long)公(gong)園(yuan)標(biao)本(ben)的(de)(de)(de)頭顱骨(gu)(gu)(gu)上有一些不同的(de)(de)(de)特征(zheng),認為(wei)(wei)這代表一個(ge)新的(de)(de)(de)達斯(si)(si)(si)布雷(lei)龍(long)(long)(long)物(wu)(wu)種。這個(ge)新物(wu)(wu)種的(de)(de)(de)圖畫經已被(bei)出版,但仍(reng)有待(dai)正式(shi)的(de)(de)(de)命名及描述。
在(zai)(zai)1990年(nian),新(xin)(xin)墨(mo)(mo)西(xi)(xi)哥州的(de)(de)嘉德蘭組(zu)發現(xian)了(le)一個(ge)(ge)新(xin)(xin)的(de)(de)暴龍(long)科標本,包括頭顱骨(gu)碎(sui)片(pian)、肋骨(gu)及部份后(hou)(hou)肢,被編(bian)入(ru)后(hou)(hou)彎齒龍(long),后(hou)(hou)彎齒龍(long)的(de)(de)狀態是(shi)個(ge)(ge)疑名。后(hou)(hou)來很多(duo)學者都將這個(ge)(ge)標本,連同(tong)一些其(qi)他(ta)新(xin)(xin)墨(mo)(mo)西(xi)(xi)哥州發現(xian)的(de)(de)化石(shi),重新(xin)(xin)歸類于達(da)斯布雷龍(long)屬(shu)中的(de)(de)未命名種。在(zai)(zai)2010年(nian)的(de)(de)一個(ge)(ge)研(yan)究(jiu),認為這個(ge)(ge)新(xin)(xin)墨(mo)(mo)西(xi)(xi)哥物種,其(qi)實是(shi)早期的(de)(de)暴龍(long)科,并建立為新(xin)(xin)屬(shu),Bistahieversor。目(mu)前對(dui)嘉德蘭組(zu)的(de)(de)年(nian)代(dai)有所爭議,一些研(yan)究(jiu)指出(chu)其(qi)年(nian)代(dai)屬(shu)于坎帕階晚期,而其(qi)他(ta)研(yan)究(jiu)則認為是(shi)麥斯特里希特階早期。
于(yu)1992年(nian)(nian),杰(jie)克·霍納(Jack Horner)及他的(de)(de)(de)(de)同僚發(fa)(fa)表一(yi)(yi)(yi)份有(you)(you)關美國蒙大拿州雙麥(mai)迪遜(xun)(xun)組(zu)較上層的(de)(de)(de)(de)新發(fa)(fa)現暴(bao)龍(long)(long)科(ke)(ke)恐龍(long)(long)的(de)(de)(de)(de)初步報(bao)告,認(ren)為這些新化(hua)石(shi)(shi)是(shi)達(da)斯布雷(lei)龍(long)(long)及后期暴(bao)龍(long)(long)的(de)(de)(de)(de)過(guo)渡物種,其年(nian)(nian)代為坎潘階。在2001年(nian)(nian),雙麥(mai)迪遜(xun)(xun)組(zu)的(de)(de)(de)(de)上層發(fa)(fa)現另一(yi)(yi)(yi)個(ge)部份骨骼,在其下腹內保存了一(yi)(yi)(yi)頭(tou)鴨嘴龍(long)(long)科(ke)(ke)的(de)(de)(de)(de)幼年(nian)(nian)個(ge)體(ti)化(hua)石(shi)(shi)。這個(ge)標(biao)本(ben)被歸類于(yu)達(da)斯布雷(lei)龍(long)(long)的(de)(de)(de)(de)一(yi)(yi)(yi)種,但卻沒有(you)(you)明定(ding)是(shi)哪一(yi)(yi)(yi)個(ge)種。在雙麥(mai)迪遜(xun)(xun)的(de)(de)(de)(de)骨床中,曾(ceng)發(fa)(fa)現最(zui)少三(san)個(ge)以上的(de)(de)(de)(de)達(da)斯布雷(lei)龍(long)(long)化(hua)石(shi)(shi)。這些標(biao)本(ben)都沒有(you)(you)被詳細描(miao)述,但柯爾認(ren)為所(suo)有(you)(you)的(de)(de)(de)(de)雙麥(mai)迪遜(xun)(xun)化(hua)石(shi)(shi)都是(shi)達(da)斯布雷(lei)龍(long)(long)屬中的(de)(de)(de)(de)第(di)三(san)個(ge)未(wei)被命名種。
雖然達(da)斯布雷(lei)龍的化(hua)石(shi)并不(bu)像(xiang)著名的近親霸王龍那(nei)樣地(di)驚人地(di)常見和普遍(bian)被發(fa)現,但都(dou)足以讓古生物學家來研(yan)究其(qi)生物學的某些范(fan)疇。目(mu)前至少(shao)發(fa)現了14個標本,不(bu)算(suan)上(shang)零碎(sui)(sui)的骨(gu)骼碎(sui)(sui)片和私人收藏家的化(hua)石(shi)。
于(yu)坎帕階晚期的北美洲,達斯(si)布(bu)(bu)雷龍(long)與蛇發女怪龍(long)生(sheng)存于(yu)相同時(shi)代的相同地區(qu)。這(zhe)是少數兩個暴龍(long)科的屬共存的例子(zi)。在現(xian)今的獵食(shi)動物(wu)中,體型相似(si)的獵食(shi)動物(wu)因為(wei)解剖學、行為(wei)或地理(li)的原因,會(hui)區(qu)分成(cheng)不同的生(sheng)態位(wei),以限(xian)制競(jing)爭(zheng)。有幾個研究嘗(chang)試解釋達斯(si)布(bu)(bu)雷龍(long)及蛇發女怪龍(long)的生(sheng)態位(wei)差異。
戴爾(er)·羅(luo)素假設(she)較(jiao)輕盈、常見的(de)(de)(de)蛇發(fa)女怪龍(long)(long)(long)可能(neng)獵食當時繁盛的(de)(de)(de)鴨嘴龍(long)(long)(long)科,而較(jiao)強壯、稀少(shao)的(de)(de)(de)達斯(si)布(bu)雷(lei)龍(long)(long)(long)則專門獵食數(shu)量較(jiao)小、防御較(jiao)好的(de)(de)(de)角(jiao)龍(long)(long)(long)科。但(dan)是,在雙麥迪(di)遜組發(fa)現(xian)的(de)(de)(de)達斯(si)布(bu)雷(lei)龍(long)(long)(long)標本,在其胃部保(bao)存了鴨嘴龍(long)(long)(long)科幼(you)年體的(de)(de)(de)已消化(hua)化(hua)石。暴龍(long)(long)(long)亞科(例(li)如(ru)(ru)達斯(si)布(bu)雷(lei)龍(long)(long)(long))有(you)(you)著較(jiao)高及較(jiao)寬的(de)(de)(de)口鼻部,比有(you)(you)較(jiao)低口鼻部的(de)(de)(de)艾伯塔龍(long)(long)(long)亞科(例(li)如(ru)(ru)蛇發(fa)女怪龍(long)(long)(long))更為強壯,不(bu)(bu)過牙齒的(de)(de)(de)強度則差(cha)異不(bu)(bu)大。這(zhe)顯示兩者在攝食的(de)(de)(de)技巧(qiao)或食性(xing)都有(you)(you)所不(bu)(bu)同。
其他(ta)學(xue)者(zhe)認(ren)為(wei)它們之間的(de)競(jing)爭受(shou)到地理(li)區(qu)分(fen)(fen)(fen)(fen)的(de)限制。不像其他(ta)的(de)恐(kong)(kong)龍(long)(long)(long)類,它們的(de)區(qu)分(fen)(fen)(fen)(fen)似(si)乎(hu)與離海岸(an)的(de)距(ju)離沒(mei)有(you)關(guan)聯,而也與海拔(ba)高或低(di)無關(guan)。但是,雖(sui)然生(sheng)活區(qu)域有(you)部(bu)分(fen)(fen)(fen)(fen)的(de)重(zhong)疊,蛇發女怪龍(long)(long)(long)似(si)乎(hu)在北(bei)方較為(wei)普(pu)遍(bian),而達斯布(bu)(bu)雷龍(long)(long)(long)則傾向于南(nan)方。其他(ta)的(de)恐(kong)(kong)龍(long)(long)(long)亦有(you)類似(si)的(de)地理(li)分(fen)(fen)(fen)(fen)布(bu)(bu)。在坎潘階,鴨嘴(zui)(zui)龍(long)(long)(long)亞(ya)科(ke)(ke)與開(kai)角龍(long)(long)(long)亞(ya)科(ke)(ke)繁盛于雙麥迪遜組與北(bei)美洲(zhou)西南(nan)部(bu)。湯瑪斯·荷茲(Thomas Holtz)指出這個(ge)地理(li)分(fen)(fen)(fen)(fen)布(bu)(bu)型式,顯示暴(bao)龍(long)(long)(long)亞(ya)科(ke)(ke)、開(kai)角龍(long)(long)(long)亞(ya)科(ke)(ke)及(ji)鴨嘴(zui)(zui)龍(long)(long)(long)亞(ya)科(ke)(ke)都有(you)著同(tong)樣的(de)生(sheng)態位(wei)傾向。他(ta)認(ren)為(wei)于麥斯特(te)里希特(te)階末期,暴(bao)龍(long)(long)(long)亞(ya)科(ke)(ke)(如暴(bao)龍(long)(long)(long))、鴨嘴(zui)(zui)龍(long)(long)(long)亞(ya)科(ke)(ke)及(ji)開(kai)角龍(long)(long)(long)亞(ya)科(ke)(ke)(如三角龍(long)(long)(long))廣泛分(fen)(fen)(fen)(fen)布(bu)(bu)在北(bei)美洲(zhou)西部(bu),而艾伯塔(ta)龍(long)(long)(long)亞(ya)科(ke)(ke)及(ji)尖角龍(long)(long)(long)亞(ya)科(ke)(ke)已滅(mie)絕,賴氏龍(long)(long)(long)亞(ya)科(ke)(ke)則已很稀少(shao)。
在(zai)恐龍(long)(long)公園地(di)(di)層發現的(de)(de)一個(ge)年(nian)輕達斯布(bu)雷(lei)龍(long)(long)標本,面(mian)部上有被其(qi)(qi)他(ta)暴龍(long)(long)科咬(yao)(yao)傷的(de)(de)痕跡。這(zhe)個(ge)咬(yao)(yao)痕已經(jing)痊愈,顯(xian)示它在(zai)這(zhe)次事件(jian)后存活過(guo)來。在(zai)同一地(di)(di)層發現的(de)(de)一個(ge)成年(nian)達斯布(bu)雷(lei)龍(long)(long)標本也有相似咬(yao)(yao)痕,可(ke)見這(zhe)類(lei)攻(gong)擊(ji)并不限于年(nian)輕的(de)(de)動(dong)物(wu)。雖然這(zhe)些(xie)攻(gong)擊(ji)可(ke)能是來自其(qi)(qi)他(ta)物(wu)種,但獵食動(dong)物(wu)常發生(sheng)物(wu)種內的(de)(de)打斗、攻(gong)擊(ji)行為(wei)。目前已在(zai)其(qi)(qi)他(ta)的(de)(de)暴龍(long)(long)科(如(ru)蛇發女(nv)怪龍(long)(long)及(ji)暴龍(long)(long))以及(ji)其(qi)(qi)他(ta)的(de)(de)獸腳(jiao)亞目(如(ru)中華盜龍(long)(long)及(ji)蜥(xi)鳥盜龍(long)(long))發現這(zhe)種面(mian)部的(de)(de)攻(gong)擊(ji)痕跡。Darren Tanke與菲力·柯爾(Phil Currie)提(ti)出假說,指出這(zhe)些(xie)攻(gong)擊(ji)是因為(wei)競爭疆域、食物(wu)資(zi)源、或支配群(qun)族而出現的(de)(de)種內競爭。
達(da)(da)斯(si)布(bu)雷(lei)(lei)(lei)龍(long)群(qun)體生(sheng)活(huo)的(de)證據是(shi)(shi)發現(xian)于(yu)蒙(meng)大(da)拿州雙麥(mai)迪遜組骨(gu)床(chuang)的(de)化石。骨(gu)床(chuang)內有三頭達(da)(da)斯(si)布(bu)雷(lei)(lei)(lei)龍(long)的(de)遺(yi)骸,包括一(yi)頭大(da)的(de)成年(nian)個體、一(yi)頭小的(de)幼龍(long)、及另一(yi)頭中型大(da)小的(de)達(da)(da)斯(si)布(bu)雷(lei)(lei)(lei)龍(long)。同(tong)一(yi)地(di)點還發現(xian)最少五頭鴨嘴龍(long)科(ke)(ke)化石。地(di)質學證據顯示,這些(xie)遺(yi)骸并非被河流沖積在(zai)(zai)一(yi)起,而(er)是(shi)(shi)在(zai)(zai)短暫時(shi)間遭到集體掩葬。鴨嘴龍(long)科(ke)(ke)的(de)遺(yi)骸是(shi)(shi)分(fen)散的(de),并且(qie)有很多暴龍(long)科(ke)(ke)牙(ya)齒的(de)咬痕,可見達(da)(da)斯(si)布(bu)雷(lei)(lei)(lei)龍(long)在(zai)(zai)死前曾吃過(guo)這些(xie)鴨嘴龍(long)科(ke)(ke)動物。這些(xie)動物的(de)死亡原因并不(bu)清楚。菲力·柯爾(er)猜(cai)測達(da)(da)斯(si)布(bu)雷(lei)(lei)(lei)龍(long)是(shi)(shi)群(qun)體狩獵的(de),但無法確定。其他科(ke)(ke)學家則對達(da)(da)斯(si)布(bu)雷(lei)(lei)(lei)龍(long)及其他大(da)型獸腳亞(ya)目的(de)群(qun)體活(huo)動證據抱有懷疑。
古生(sheng)(sheng)(sheng)物(wu)學(xue)家格(ge)里高利(li)·艾(ai)利(li)克森(Gregory Erickson)及其同僚研究(jiu)了暴龍(long)(long)(long)科的(de)(de)生(sheng)(sheng)(sheng)長及壽命。透過(guo)骨頭組(zu)織學(xue)的(de)(de)分析,可以(yi)確定標(biao)本(ben)死亡(wang)時的(de)(de)年(nian)(nian)齡。將(jiang)不(bu)同個(ge)體的(de)(de)年(nian)(nian)齡與體型(xing)繪(hui)制(zhi)為圖(tu)表,就可得到生(sheng)(sheng)(sheng)長曲線(xian)。艾(ai)利(li)克森指出暴龍(long)(long)(long)科經歷長時間的(de)(de)幼龍(long)(long)(long)狀態,會(hui)在(zai)(zai)4年(nian)(nian)內急(ji)速成長。這(zhe)個(ge)急(ji)速成長的(de)(de)階(jie)段會(hui)在(zai)(zai)達(da)到性(xing)成熟時完(wan)結,成年(nian)(nian)后(hou)的(de)(de)生(sheng)(sheng)(sheng)長率(lv)會(hui)減慢。艾(ai)利(li)克森只(zhi)研究(jiu)了從雙麥迪遜組(zu)發現的(de)(de)達(da)斯(si)布(bu)雷(lei)龍(long)(long)(long)標(biao)本(ben),但這(zhe)些標(biao)本(ben)都有(you)相同的(de)(de)生(sheng)(sheng)(sheng)長模式。與艾(ai)伯塔龍(long)(long)(long)相比,因達(da)斯(si)布(bu)雷(lei)龍(long)(long)(long)的(de)(de)體重(zhong)較高,在(zai)(zai)急(ji)速成長期有(you)著較快的(de)(de)生(sheng)(sheng)(sheng)長率(lv)。達(da)斯(si)布(bu)雷(lei)龍(long)(long)(long)的(de)(de)最大生(sheng)(sheng)(sheng)長率(lv)為每(mei)年(nian)(nian)180公斤(jin)(假設成年(nian)(nian)的(de)(de)達(da)斯(si)布(bu)雷(lei)龍(long)(long)(long)體重(zhong)是3500公斤(jin))。其他(ta)學(xue)者指出達(da)斯(si)布(bu)雷(lei)龍(long)(long)(long)應為更重(zhong),不(bu)過(guo)這(zhe)只(zhi)會(hui)影響達(da)斯(si)布(bu)雷(lei)龍(long)(long)(long)生(sheng)(sheng)(sheng)長率(lv)的(de)(de)量,而非整體模式。
艾(ai)利克(ke)(ke)森(sen)(sen)等人(ren)將每一個年齡層的(de)標本(ben)作成(cheng)(cheng)(cheng)表格,整(zheng)理出(chu)(chu)艾(ai)伯塔(ta)龍群族的(de)生長(chang)(chang)模式。艾(ai)利克(ke)(ke)森(sen)(sen)指(zhi)出(chu)(chu)艾(ai)伯塔(ta)龍的(de)幼(you)年個體(ti)(ti)化(hua)石紀錄較(jiao)為稀少,處在(zai)急(ji)速成(cheng)(cheng)(cheng)長(chang)(chang)期的(de)接(jie)近(jin)成(cheng)(cheng)(cheng)年個體(ti)(ti)及(ji)成(cheng)(cheng)(cheng)年個體(ti)(ti)則(ze)更為常見。這可(ke)能是因為化(hua)石化(hua)過程與(yu)挖(wa)掘化(hua)石的(de)偏差(cha)(cha)。艾(ai)利克(ke)(ke)森(sen)(sen)假設這些差(cha)(cha)異是來自幼(you)龍在(zai)某(mou)一體(ti)(ti)型(xing)的(de)低死(si)(si)亡率,就(jiu)像現(xian)今的(de)某(mou)些大型(xing)哺乳類(例如象)一樣。因為暴龍科在(zai)兩歲時體(ti)(ti)型(xing)就(jiu)超越(yue)了所(suo)有同期的(de)獵食動(dong)物,所(suo)以在(zai)缺乏被獵食的(de)情況下,出(chu)(chu)現(xian)低死(si)(si)亡率。古生物學(xue)家并沒有足夠的(de)達斯(si)布雷(lei)龍化(hua)石來進行類似的(de)分析,但艾(ai)利克(ke)(ke)森(sen)(sen)則(ze)認(ren)為達斯(si)布雷(lei)龍也有類似的(de)生長(chang)(chang)趨勢。
目前(qian)(qian)(qian)已(yi)發現(xian)的(de)(de)達(da)(da)斯布雷(lei)龍(long)化石(shi)都發現(xian)于上白(bai)堊紀(ji)坎帕階中(zhong)至晚(wan)期(qi)的(de)(de)地(di)層,距今約7700萬(wan)-7400萬(wan)年前(qian)(qian)(qian)。在(zai)白(bai)堊紀(ji)中(zhong)期(qi),北美(mei)洲被(bei)西(xi)部(bu)(bu)內陸海道(dao)一分為(wei)二,蒙(meng)大(da)拿(na)州及(ji)阿爾伯(bo)塔省大(da)部(bu)(bu)份都在(zai)海平(ping)面之(zhi)下。在(zai)這段達(da)(da)斯布雷(lei)龍(long)存活的(de)(de)時期(qi),西(xi)部(bu)(bu)拉(la)拉(la)米造(zao)山(shan)運動使(shi)得落基(ji)山(shan)脈隆起,使(shi)海道(dao)向(xiang)東方及(ji)南方后退(tui)。大(da)型河流從(cong)西(xi)側(ce)(ce)的(de)(de)山(shan)脈流至東側(ce)(ce)的(de)(de)海道(dao),當中(zhong)的(de)(de)沉積(ji)物形成廣大(da)的(de)(de)海岸平(ping)原,成為(wei)朱迪(di)斯河群的(de)(de)雙麥迪(di)遜組與其(qi)他(ta)的(de)(de)地(di)層。約7300萬(wan)年前(qian)(qian)(qian),海道(dao)再次向(xiang)西(xi)方與北方海侵,逐漸淹沒恐(kong)龍(long)公園組,涵蓋美(mei)國(guo)西(xi)部(bu)(bu)及(ji)加拿(na)大(da)西(xi)部(bu)(bu)。
達斯(si)(si)布(bu)雷(lei)龍生(sheng)(sheng)(sheng)活在西部內(nei)陸(lu)(lu)海(hai)道西岸的(de)(de)(de)(de)(de)廣大沖積平(ping)原。大型的(de)(de)(de)(de)(de)河流(liu)流(liu)經土地(di)(di),有時(shi)(shi)會出(chu)現(xian)泛(fan)濫,形(xing)成新的(de)(de)(de)(de)(de)沉積層。當水源充足時(shi)(shi),可以維持大量的(de)(de)(de)(de)(de)植物及(ji)(ji)動(dong)物生(sheng)(sheng)(sheng)活,但這(zhe)(zhe)個區(qu)域會發生(sheng)(sheng)(sheng)周期(qi)性(xing)的(de)(de)(de)(de)(de)干旱,造(zao)成大量生(sheng)(sheng)(sheng)物的(de)(de)(de)(de)(de)死(si)亡,形(xing)成朱(zhu)迪(di)斯(si)(si)河群與雙麥迪(di)遜(xun)組的(de)(de)(de)(de)(de)眾(zhong)多骨床。在現(xian)今的(de)(de)(de)(de)(de)東非也有相似的(de)(de)(de)(de)(de)情況(kuang)。平(ping)原西方的(de)(de)(de)(de)(de)周期(qi)性(xing)火(huo)(huo)(huo)山噴發,產生(sheng)(sheng)(sheng)的(de)(de)(de)(de)(de)火(huo)(huo)(huo)山灰會影響整個地(di)(di)區(qu),這(zhe)(zhe)成大量的(de)(de)(de)(de)(de)死(si)亡,而同(tong)時(shi)(shi)豐(feng)富了土壤,有助于日后(hou)的(de)(de)(de)(de)(de)植物生(sheng)(sheng)(sheng)長。科學家也借由(you)這(zhe)(zhe)些火(huo)(huo)(huo)山灰得出(chu)準確(que)的(de)(de)(de)(de)(de)放射(she)性(xing)測年(nian)。海(hai)平(ping)面的(de)(de)(de)(de)(de)改變,在不(bu)(bu)同(tong)時(shi)(shi)期(qi)對朱(zhu)迪(di)斯(si)(si)河群的(de)(de)(de)(de)(de)不(bu)(bu)同(tong)地(di)(di)區(qu),造(zao)成許多環境變動(dong),包括(kuo)離岸及(ji)(ji)近岸的(de)(de)(de)(de)(de)海(hai)洋生(sheng)(sheng)(sheng)態、海(hai)岸濕地(di)(di)、三角洲及(ji)(ji)礁湖、內(nei)陸(lu)(lu)的(de)(de)(de)(de)(de)泛(fan)濫平(ping)原等。與朱(zhu)迪(di)斯(si)(si)河群的(de)(de)(de)(de)(de)其他地(di)(di)層相比,雙麥迪(di)遜(xun)組是在更內(nei)陸(lu)(lu)的(de)(de)(de)(de)(de)高海(hai)拔地(di)(di)區(qu)。
在雙麥(mai)迪遜組及朱(zhu)迪斯(si)河群有(you)(you)良(liang)好(hao)的(de)脊椎動(dong)物(wu)(wu)化石紀錄(lu),這是因為豐富的(de)動(dong)物(wu)(wu)群、周期性的(de)自然災害及大量的(de)沉積巖(yan)所造成的(de)。這些地區(qu)有(you)(you)多樣性的(de)淡(dan)水及入(ru)海口魚(yu)(yu)類化石,包(bao)括(kuo)鯊魚(yu)(yu)、鰩目、鱘魚(yu)(yu)、雀(que)鱔目及其(qi)(qi)他(ta)魚(yu)(yu)類。朱(zhu)迪斯(si)河群也(ye)保存很多水生爬行(xing)動(dong)物(wu)(wu)及兩(liang)棲動(dong)物(wu)(wu)化石,包(bao)括(kuo)有(you)(you)青蛙、鯢、龜、鱷龍(long)及鱷魚(yu)(yu)。陸地上(shang)的(de)爬行(xing)動(dong)物(wu)(wu),則有(you)(you)叉舌蜥(xi)科、石龍(long)子(zi)科、巨蜥(xi)科及蛇蜥(xi)科。天空的(de)飛(fei)行(xing)動(dong)物(wu)(wu)則包(bao)含:神(shen)龍(long)翼龍(long)科及新鳥(niao)(niao)亞綱(如(ru)虛椎鳥(niao)(niao)等(deng))。哺(bu)乳動(dong)物(wu)(wu)則包(bao)含:多瘤齒目、有(you)(you)袋(dai)目及真獸(shou)類哺(bu)乳動(dong)物(wu)(wu)。除(chu)此上(shang)述(shu)物(wu)(wu)種之外,還(huan)有(you)(you)達斯(si)布雷龍(long)及其(qi)(qi)他(ta)恐龍(long)。
在(zai)奧爾(er)德曼(man)組(zu),強健(jian)達(da)(da)斯(si)布雷(lei)龍(long)(long)(long)(long)可能獵(lie)(lie)食(shi)鴨嘴龍(long)(long)(long)(long)科(ke)(如(ru)短冠龍(long)(long)(long)(long)及(ji)亞(ya)冠龍(long)(long)(long)(long))、小型的(de)鳥(niao)(niao)腳(jiao)下目(mu)(如(ru)奔山龍(long)(long)(long)(long))、角龍(long)(long)(long)(long)科(ke)(如(ru)尖角龍(long)(long)(long)(long))、腫頭(tou)龍(long)(long)(long)(long)下目(mu)、似鳥(niao)(niao)龍(long)(long)(long)(long)下目(mu)、鐮(lian)刀龍(long)(long)(long)(long)超科(ke)及(ji)甲龍(long)(long)(long)(long)下目(mu)。其他獵(lie)(lie)食(shi)恐(kong)(kong)(kong)龍(long)(long)(long)(long)包括:傷(shang)齒(chi)龍(long)(long)(long)(long)科(ke)、竊蛋(dan)龍(long)(long)(long)(long)下目(mu)、馳龍(long)(long)(long)(long)科(ke)的(de)蜥鳥(niao)(niao)盜龍(long)(long)(long)(long)、及(ji)艾伯塔龍(long)(long)(long)(long)亞(ya)科(ke)。恐(kong)(kong)(kong)龍(long)(long)(long)(long)公(gong)(gong)園(yuan)組(zu)及(ji)雙麥迪(di)遜組(zu)有(you)著類似奧爾(er)德曼(man)組(zu)的(de)動物群組(zu)成,而恐(kong)(kong)(kong)龍(long)(long)(long)(long)公(gong)(gong)園(yuan)組(zu)則沒有(you)互(hu)相(xiang)競爭(zheng)的(de)多種大型獵(lie)(lie)食(shi)恐(kong)(kong)(kong)龍(long)(long)(long)(long)。蛇發女怪龍(long)(long)(long)(long)與達(da)(da)斯(si)布雷(lei)龍(long)(long)(long)(long)同時(shi)生(sheng)活于恐(kong)(kong)(kong)龍(long)(long)(long)(long)公(gong)(gong)園(yuan)組(zu)與雙麥迪(di)遜組(zu)上層。幼(you)年(nian)暴(bao)龍(long)(long)(long)(long)科(ke)的(de)生(sheng)態位,介乎成年(nian)暴(bao)龍(long)(long)(long)(long)科(ke)及(ji)小型的(de)獸腳(jiao)亞(ya)目(mu)之(zhi)間(jian)(jian),它們之(zhi)間(jian)(jian)的(de)體重有(you)數倍的(de)差距(ju)。