這只兇猛上龍具有巨大的口腔,20cm長的牙齒,,能夠?qū)⒍鄶?shù)的爬行動物及其它種類 恐龍撕裂成碎塊,,但是卻不幸遭受了類似關節(jié)炎的疾病
科學家于近日首次發(fā)現(xiàn),上龍的巨大關節(jié)也會飽受關節(jié)疼痛的困擾,。他們在上龍下頜處發(fā)現(xiàn)的退化狀況,,類似于人類關節(jié)炎的癥狀。上龍是遠古時期的海洋爬行動物,,生活在1.5億年前,。這標志著科學家首次在侏羅紀時期爬行動物化石上,,發(fā)現(xiàn)類似關節(jié)炎的癥狀,。相關研究成果刊登在了國際雜志Palaeontology上。
來自布里斯托大學的一個研究小組,,檢驗了上龍亞目中上龍的巨大化石樣品,,這只發(fā)現(xiàn)于英國南部威爾特郡的韋斯特伯里的上龍,死于上侏羅紀時期,,體長八米,,它具有像 鱷魚一樣的頭部,,短的脖子,,像鯨魚一樣的身體,,和四條強有力的腳蹼,,從而推動它在水中游行。
研究者發(fā)現(xiàn),,這只兇猛上龍具有巨大的口腔,,20cm長的牙齒,能夠?qū)⒍鄶?shù)的爬行動物及其它種類恐龍撕裂成碎塊,,但是卻不幸遭受了類似關節(jié)炎的疾病,。這令它的左鄂關節(jié)遭受腐蝕,導致下顎偏向一邊,。研究發(fā)現(xiàn)這只上龍被關節(jié)炎困擾了許多年,,從而吃東西時,由于上鄂牙齒的嵌入,,導致下顎上的骨頭都產(chǎn)生了磨損,。
來自布里斯托大,,專門研究骨骼的朱迪斯宣博士說:“通過研究她的疾病發(fā)現(xiàn),,這只年長的雌性上龍患的是鄂關節(jié)炎,,情況類似于年長的人類患的髖關節(jié)炎。但是這個未愈合的下巴缺陷顯示,,一段時間內(nèi)下顎功能會被削弱,,最終斷掉。帶著一個破碎的下巴,,上龍將無法進食,,最終很可能會走向死亡”。
有多個證據(jù)顯示這是只年老的雌性上龍,,像人類一樣,,換上這種疾病也成為了它衰老過程的一部分。它巨大的體型及融合了的頭蓋骨顯示了它處于成熟期,,其特別低的頭骨嵴表明它是雌性,。
上龍被認為是追擊埋伏性掠食者,,以魚,、魷魚及其它海洋爬行動物為食。它們處于食物鏈的頂端,,因此只需要避開其它上龍類的攻擊即可,。
這項研究的合作者邁克本頓教授補充說:“在目前仍存活的動物里也能發(fā)現(xiàn)這種疾病,例如鱷魚,、抹香鯨,,它們能在能量還能自給的情況下存活數(shù)年。但是這個過程肯定是痛苦的,。記得梅爾維爾電影《白鯨記》中虛構的那只可憐的白鯨,,也是遭受彎曲下頜的困擾”。(生物谷Bioon.com)
doi:10.1111/j.1475-4983.2012.01151.x
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Cranial anatomy, taxonomic implications and palaeopathology of an Upper Jurassic pliosaur (Reptilia: Sauropterygia) from Westbury, Wiltshire, UK
JUDYTH SASSOON1, LESLIE F. NOÈ2, MICHAEL J. BENTON1,†
Complete skulls of giant marine reptiles of the Late Jurassic are rare, and so the discovery of the 1.8-m-long skull of a pliosaur from the Kimmeridge Clay Formation (Kimmeridgian) of Westbury, Wiltshire, UK, is an important find. The specimen shows most of the cranial and mandibular anatomy, as well as a series of pathological conditions. It was previously referred to Pliosaurus brachyspondylus, but it can be referred reliably only to the genus Pliosaurus, because species within the genus are currently in need of review. The new specimen, together with another from the same locality, also referred to P. brachyspondylus, will be crucial in that systematic revision, and it is likely that the genus Pliosaurus will be found to include several genera. The two Westbury Pliosaurus specimens share many features, including the form of the teeth, but marked differences in the snout and parietal crest suggest sexual dimorphism; the present specimen is probably female. The large size of the animal, the extent of sutural fusion and the pathologies suggest this is an ageing individual. An erosive arthrotic condition of the articular glenoids led to prolonged jaw misalignment, generating a suite of associated bone and dental pathologies. Further damage to the jaw joint may have been the cause of death.