Department of Biological Sciences, Benedictine University, Lisle, IL, USA.
School of Information, University of Michigan, Ann Arbor, MI, USA.
Nat Ecol Evol. 2022 Mar;6(3):263-272. doi: 10.1038/s41559-021-01656-0. Epub 2022 Feb 10.
Origins of higher taxonomic groups entail dramatic and nearly simultaneous changes in morphology and ecological function, limiting our ability to disentangle the drivers of evolutionary diversification. Here we phylogenetically compare the anatomy and life habits of Cambrian-Ordovician echinoderms to test which facet better facilitates future success. Rates of morphological evolution are faster and involve more volatile trait changes, allowing morphological disparity to accrue faster and earlier in the Cambrian. However, persistent life-habit evolution throughout the early Palaeozoic, combined with iterative functional convergence within adaptive strategies, results in major expansion of ecospace and functional diversity. The interactions between tempo, divergence and convergence demonstrate not only that anatomical novelty precedes ecological success, but also that ecological innovation is constrained, even during a phylum's origin.
高等分类群的起源需要形态和生态功能的巨大而几乎同时的变化，限制了我们区分进化多样化驱动因素的能力。在这里，我们通过系统发育比较了寒武纪-奥陶纪棘皮动物的解剖结构和生活习性，以检验哪一方面更有利于未来的成功。形态进化的速度更快，涉及更多不稳定的特征变化，使形态差异在寒武纪更快更早地积累。然而，整个古生代早期持续的生活习性进化，以及在适应性策略内的迭代功能趋同，导致生态位和功能多样性的重大扩展。时率、分歧和趋同之间的相互作用不仅表明解剖学上的新颖性先于生态成功，而且表明即使在一个门的起源时期，生态创新也受到限制。
