Calcification in marine molluscs: how costly is it?
Calcification in marine molluscs: how costly is it?
复制标题
海洋软体动物钙化：成本有多高？
DOI：
--
复制
发表时间：
1992
影响因子：
11.1
通讯作者：
A. R. Palmer
中科院分区：
文献类型：
--
作者：
A. R. Palmer
尽管钙化对我们理解海洋无脊椎动物的骨骼进化至关重要，但钙化的成本仍然难以捉摸，原因很简单：CaCO3是一种无机材料。因此，它的成本完全来自积累、运输和沉淀CaCO3的代谢费用，通常不能与其他代谢成本分开。传统上，钙化成本被忽略，总的壳层成本被假设为仅来自骨骼有机基质。这里估计的成本是由于两种岩岸腹足类(Nucella lamellosa和Nucella Lapillas)贝壳厚度的巨大自然变化所允许的。在野外和实验室，来自三个不同实验的数据显示，在特定的实验条件下，一群蜗牛产生额外的外壳材料，也消耗了额外的食物。钙化的成本是通过计算在普通组织生长速度下产生的单位额外外壳所吸收的额外能量，然后减去有机基质的成本来估计的。当CaCO3的浓度为1-2J/mg时，这里报告的钙化成本大约是每克软体动物贝壳中以蛋白质为主的有机部分的5%。这可能解释了为什么高有机含量的钙质微结构在进化上变得不那么常见了。
Although crucial to our understanding of skeletal evolution in marine invertebrates, the cost of calcification has remained elusive for a simple reason: CaCO3 is an inorganic material. Its cost thus derives solely from the metabolic expenses of accumulating, transporting, and precipitating CaCO3 and cannot normally be separated from other metabolic costs. Traditionally, calcification cost has been ignored and total shell cost has been assumed to derive solely from skeletal organic matrix. The cost estimated here was permitted by the substantial natural variation in shell thickness in two rocky-shore gastropods (Nucella lamellosa and Nucella lapillus). In both the field and laboratory, data from three separate experiments revealed that groups of snails producing extra shell material under a particular set of experimental conditions also consumed extra food. The cost of calcification was estimated by computing the extra energy assimilated per unit extra shell produced at a common rate of tissue growth and then subtracting the cost of the organic matrix. At 1-2 J/mg of CaCO3, the calcification cost reported here is roughly 5% of that for the predominantly proteinaceous organic fraction of molluscan shells on a per-gram basis. This may explain why calcareous microstructures high in organic content have become less common evolutionarily.