Impact of diagenesis and maturation on the survival of eumelanin in the fossil record
Impact of diagenesis and maturation on the survival of eumelanin in the fossil record
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DOI：
10.1016/j.orggeochem.2013.09.002
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发表时间：
2013-11-01
影响因子：
3
通讯作者：
Simon, John D.
中科院分区：
文献类型：
--
作者：
Glass, Keely;Ito, Shosuke;Simon, John D.
黑色素是聚合酚类色素，根据其化学结构和分子前体分为两组：真黑素（棕黑色）和褐黑素（黄红色）。真黑素具有很强的弹性，并有一个已被证实的化石记录，至少可以追溯到200 Ma。它广泛存在于生物界，存在于真菌、头足类动物的墨囊、鸟类的羽毛以及哺乳动物的毛发、皮肤、眼睛、大脑和内耳中。虽然化石真黑素的存在和化学属性已被记录，但很少有数据限制其长期生存。在这里，我们使用的分析技术的多样性，比较化学和形态的三个存款类似的年龄和岩性，但不同的成熟的历史的头足类动物墨水。我们证明了真黑素的化学性质在油窗期开始改变，并且在很大程度上与年龄无关。幸存的黑色素的减少伴随着有机大分子物质（干酪根）相对丰度的增加，但对于正确解释化石至关重要的是，并不伴随着颗粒形态的一致变化。(C)2013爱思唯尔有限公司保留所有权利。
Melanins are polymeric phenolic pigments classified into two groups based on their chemical structures and molecular precursors: eumelanin (brown-black) and pheomelanin ( yellow-red). Eumelanin is highly resilient and has a proven fossil record, extending back at least similar to 200 Ma. It is widespread in the biological world, occurring in fungi, the ink sacs of cephalopods, the feathers of birds, and the hair, skin, eyes, brain and inner ears of mammals. Although the presence and chemical attributes of fossil eumelanin have been documented, there are few data constraining its long term survival. Here we use a diversity of analytical techniques to compare the chemistry and morphology of fossilized cephalopod ink from three deposits of similar age and lithology, but different maturation histories. We demonstrate that the chemistry of eumelanin begins to alter at the onset of the oil window and is largely independent of age. The decrease in surviving melanin is accompanied by an increase in the relative abundance of organic macromolecular material (kerogen) but, critically for the correct interpretation of fossils, is not accompanied by a consistent change in granule morphology. (C) 2013 Elsevier Ltd. All rights reserved.