美國加州理工學(xué)院科學(xué)家6月23日發(fā)表研究報告說,,他們通過分析牙齒估測了恐龍體溫,,這一方法將有助于更深入了解恐龍生活習性。研究報告發(fā)表在《科學(xué)》雜志上,。
食草龍牙齒
在動物牙齒內(nèi),,碳-13和氧-18等重同位素通常聚集在一起,具體聚集形式由溫度決定,。“在非常高的溫度下,,這些同位素以更隨機方式分布,較為分散,;在低溫下,,你會發(fā)現(xiàn)它們更緊密地聚集在一起,,”研究報告的主要作者羅伯特·伊格爾說。
科學(xué)家收集了分別來自坦桑尼亞和美國的11顆恐龍牙齒,,并分析了其中蘊含的同位素碳-13和氧-18,。結(jié)果確認,一種名為“腕龍”的恐龍的體溫在38攝氏度左右,。
腕龍體長超過20米,,體重80噸左右,是名副其實的龐然大物,。伊格爾說,,38攝氏度的體溫可能意味著這種恐龍行動起來比較快速,而非人們先前所認為的非常遲緩,。
科學(xué)家一直試圖通過各種方法來估測恐龍體溫,,以了解恐龍的行走速度和生活習性。為了確認分析牙齒推測體溫的準確性,,伊格爾曾經(jīng)在活著的大象和鯊魚身上驗證這項技術(shù),。(生物谷Bioon.com)
生物谷推薦原文出處:
Science DOI: 10.1126/science.1206196
Dinosaur Body Temperatures Determined from Isotopic (13C-18O) Ordering in Fossil Biominerals
Eagle, Robert A.; Tütken, Thomas; Martin, Taylor S.; Tripati, Aradhna K.; Fricke, Henry C.; Connely, Melissa; Cifelli, Richard L.; Eiler, John M.
The nature of the physiology and thermal regulation of the nonavian dinosaurs is the subject of debate. Previously, arguments have been made for both endothermic and ectothermic metabolisms based on differing methodologies. Here, we used clumped isotope thermometry to determine body temperatures from the fossilized teeth of large Jurassic sauropods. Our data indicate body temperatures of 36 to 38°C, which are similar to most modern mammals. This temperature range is 4 to 7°C lower than predicted by a model that showed scaling of dinosaur body temperature with mass, which could indicate that sauropods had mechanisms to prevent excessively high body temperatures being reached due to their gigantic size.