Environmentally controlled variation in the shell structure of a pelecypod species
Environmentally controlled variation in the shell structure of a pelecypod species
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介壳动物物种壳结构的环境控制变化
DOI：
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发表时间：
1964
期刊：
影响因子：
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通讯作者：
J. Dodd
中科院分区：
文献类型：
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作者：
J. Dodd
贝壳的结构随其形成温度的不同而不同。该物种的外壳由四个主要层组成，骨膜层(完全有机)，珍珠层(文石)，内外棱柱层(方解石)。贝壳中文石的百分比随着温度的变化而变化，这可以从贝壳的薄片和抛光部分以及X射线确定的文石百分比中看出。内棱柱层的发展程度强烈地依赖于生长温度。为了定量地表达这种关系，已经设计了一个系统。珍珠质结构的楔形经常突出到内部棱柱层中，每年形成，使贝壳的年龄确定成为可能。由这些楔形区确定的生长速率与生长区域的平均温度成正比。根据贝壳结构变化定量测定该物种的古温度是可能的。此外，其他物种的贝壳结构，特别是那些贝壳由文石和方解石组合而成的物种，可能会被用于确定古温度。
The structure of the shell of the pelecypod Mytilus californianus varies with the temperature of its formation. This species has a shell composed of four principal layers, the periostracum (entirely organic), nacreous layer (aragonite), and outer and inner prismatic layers (calcite). The percentage of aragonite in the shell varies with temperature, as can be shown in thin and polished sections of the shell, as well as by X-ray-determined percentage of aragonite. The extent of development of the inner prismatic layer is strongly dependent on growth temperature. A system has been devised for quantitatively expressing this relation- ship. Wedges of nacreous structure which often project into the inner prismatic layer form annually, making age determination of the shell possible. Growth rates determined from these wedges are directly proportional to mean temperature of the growth locality. Quantita- tive paleotemperature determination based on shell-structure variation in this species is pos- sible. Moreover, the shell structure of other species, particularly those having shells composed of a combination of aragonite and calcite, can potentially be used for determining paleotem- peratures.