Harvey Virginia L, LeFebvre Michelle J, deFrance Susan D, Toftgaard Casper, Drosou Konstantina, Kitchener Andrew C, Buckley Michael
Manchester Institute of Biotechnology, School of Earth and Environmental Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, UK.
Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA.
R Soc Open Sci. 2019 Oct 30;6(10):191137. doi: 10.1098/rsos.191137. eCollection 2019 Oct.
Advancements in molecular science are continually improving our knowledge of marine turtle biology and evolution. However, there are still considerable gaps in our understanding, such as past marine turtle distributions, which can benefit from advanced zooarchaeological analyses. Here, we apply collagen fingerprinting to 130 archaeological marine turtle bone samples up to approximately 2500 years old from the Caribbean and Florida's Gulf Coast for faunal identification, finding the vast majority of samples (88%) to contain preserved collagen despite deposition in the tropics. All samples can be identified to species-level with the exception of the Kemp's ridley () and olive ridley () turtles, which can be separated to genus level, having diverged from one another only approximately 5 Ma. Additionally, we identify a single homologous peptide that allows the separation of archaeological green turtle samples, spp., into two distinct groups, which potentially signifies a difference in genetic stock. The majority of the archaeological samples are identified as green turtle ( spp.; 63%), with hawksbill (; 17%) and ridley turtles ( spp; 3%) making up smaller proportions of the assemblage. There were no molecular identifications of the loggerhead turtle () in the assemblage despite 9% of the samples being morphologically identified as such, highlighting the difficulties in relying on morphological identifications alone in archaeological remains. Finally, we present the first marine turtle molecular phylogeny using collagen (I) amino acid sequences and find our analyses match recent phylogenies based on nuclear and mitochondrial DNA. Our results highlight the advantage of using collagen fingerprinting to supplement morphological analyses of turtle bones and support the usefulness of this technique for assessing their past distributions across the Caribbean and Florida's Gulf Coast, especially in these tropical environments where DNA preservation may be poor.
分子科学的进步不断增进我们对海龟生物学和进化的了解。然而，我们的认识仍存在相当大的差距，比如过去海龟的分布情况，而先进的动物考古分析有助于填补这些空白。在这里，我们对来自加勒比地区和佛罗里达州墨西哥湾沿岸的130份距今约2500年的考古海龟骨骼样本进行了胶原蛋白指纹识别，以进行动物群鉴定，结果发现尽管这些样本沉积在热带地区，但绝大多数样本（88%）仍含有保存下来的胶原蛋白。除了肯氏丽龟（）和榄蠵龟（），所有样本都能鉴定到物种水平，这两种丽龟只能鉴定到属级水平，它们大约在500万年前才彼此分化。此外，我们识别出一种同源肽，它能将考古绿海龟样本（ 属）分为两个不同的组，这可能意味着基因库存在差异。大多数考古样本被鉴定为绿海龟（ 属；63%），玳瑁（；17%）和丽龟（ 属；3%）在样本组合中所占比例较小。尽管9%的样本在形态上被鉴定为蠵龟，但该样本组合中没有对蠵龟的分子鉴定结果，这凸显了仅依靠形态鉴定来识别考古遗迹的困难。最后，我们利用胶原蛋白（I）氨基酸序列构建了首个海龟分子系统发育树，发现我们的分析结果与最近基于核DNA和线粒体DNA的系统发育树相匹配。我们的研究结果突出了使用胶原蛋白指纹识别来补充海龟骨骼形态分析的优势，并支持了这项技术在评估过去海龟在加勒比地区和佛罗里达州墨西哥湾沿岸分布情况方面的实用性，特别是在这些DNA保存可能较差的热带环境中。
