Phylogenetic, ecological, and ontogenetic factors influencing the biochemical structure of the blubber of odontocetes
Phylogenetic, ecological, and ontogenetic factors influencing the biochemical structure of the blubber of odontocetes
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DOI：
10.1007/s00227-006-0489-8
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发表时间：
2007-03-01
期刊：
影响因子：
2.4
通讯作者：
Koopman, Heather N.
中科院分区：
文献类型：
--
作者：
Koopman, Heather N.
为了探索影响齿鲸类（齿鲸）鲸脂结构的生态、系统发育和发育因素，在260个标本（30个物种代表除河豚以外的所有科）中确定了这种专门脂肪组织的脂质组成，其中大部分标本是在1995年至2005年期间从世界各地收集的。在大多数齿鲸类，鲸脂主要含有三酰甘油，喙鲸和抹香鲸的鲸脂主要由蜡酯（WE），表现出个体发育模式的沉积。WEs可能代表了海洋哺乳动物对深潜的适应，这些哺乳动物不依赖鲸脂储存能量。脂肪酸（FA）组成分层通过鲸脂深度，与较高浓度的饮食FA的内部和内源性FA的外层鲸脂。分层可以被认为是齿鲸类的一个特征，并且可能是通过鲸脂进行差异代谢的结果。较小的身体尺寸似乎限制了鲸脂脂质含量高。热栖息地也代表了鲸脂成分的重要选择压力。居住在较冷的沃茨的物种表现出较高的脂肪含量和增加FA分层，相比，从温暖/热带栖息地的物种。内部鲸脂的分离动员可能允许代谢酶不受低温限制地发挥作用。鲸脂脂质的组成和分布的变化表明，不同的物种可能已经进化出稍微不同的阵列的次级功能，这种专门的组织作为适应特定的生态位。
To explore ecological, phylogenetic, and developmental factors affecting the structure of blubber in Odontocetes (toothed whales), lipid composition of this specialized adipose tissue was determined in 260 specimens (30 species representing all families except the river dolphins), most of which were collected between 1995 and 2005, from all over the world. In most odontocetes, blubber contained primarily triacylglycerols; the blubber of beaked and sperm whales was dominated by wax esters (WE), exhibiting ontogenetic patterns of deposition. WEs may represent an adaptation to deep diving for marine mammals that do not rely on blubber for stored energy. Fatty acid (FA) composition was stratified through blubber depth, with higher concentrations of dietary FA in the inner and endogenous FA in the outer layers of the blubber. Stratification can be considered a characteristic feature of odontocetes, and is likely the result of differential metabolism through the blubber. Small body size appears to constrain blubber lipid content to be high. Thermal habitat also represents an important selective pressure for blubber composition. Species inhabiting colder waters exhibited both higher lipid content and increased FA stratification in blubber, compared to species from warm/tropical habitats. The isolation of mobilization to inner blubber may permit metabolic enzymes to function without limitation by lower temperatures. The variation in composition and distribution of blubber lipids in odontocetes suggests that different species may have evolved slightly diverse arrays of secondary functions for this specialized tissue as adaptations for specific ecological niches.