The essay discusses whether biotic and abiotic environments differ in their ability to speed up or slow down morphological change and the generation of new lineages. Examples from the class Branchiopoda show that morphological conservatism is associated with enemy free space in species-poor habitats dominated by abiotic factors, while Red Queen mechanisms are predominant in larger systems with complex biotic interactions. Splitting of Branchiopod main lineages is associated with increased fish predation during the Devonian. The order Cladocera adapted and remained in larger aquatic systems, and subsequently generated a variety of new families, genera and species. The order Anostraca, on the other hand, maintained its ancestral morphology and survived only as “living fossils” in isolated ponds of harsh habitats. Despite their archaic morphology, however, they possess highly sophisticated adaptations to local physicochemical properties of their extreme environment. Hence, although morphologically conservative and possessing traits typical for “living fossils”, anostracan physiological abilities are closely adapted to the challenging and variable physicochemical conditions of ponds and ephemeral pools.

中文翻译：

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形态上保守但生理上多样： Anostraca（甲壳纲：Branchiopoda）的停滞模式。

这篇文章讨论了生物和非生物环境在加速或减缓形态变化和新谱系产生的能力方面是否不同。来自 Branchiopoda 类的例子表明，形态保守主义与由非生物因素主导的物种贫乏栖息地中的敌人自由空间有关，而红皇后机制在具有复杂生物相互作用的较大系统中占主导地位。Branchiopod 主要谱系的分裂与泥盆纪期间鱼类捕食增加有关。枝角目适应并保留在更大的水生系统中，随后产生了各种新的科、属和种。另一方面，Anostraca 目保持其祖先的形态，仅在恶劣栖息地的孤立池塘中作为“活化石”幸存下来。尽管它们的形态古老，然而，它们对极端环境的局部物理化学特性具有高度复杂的适应性。因此，虽然形态保守并具有“活化石”的典型特征，但 Anostracan 的生理能力密切适应池塘和临时水池具有挑战性和多变的物理化学条件。