Pteropods are a group of planktonic gastropods that are widely regarded as biological indicators for assessing the impacts of ocean acidification. Their aragonitic shells are highly sensitive to acute changes in ocean chemistry. However, to gain insight into their potential to adapt to current climate change, we need to accurately reconstruct their evolutionary history and assess their responses to past changes in the Earth’s carbon cycle. Here, we resolve the phylogeny and timing of pteropod evolution with a phylogenomic dataset (2,654 genes) incorporating new data for 21 pteropod species and revised fossil evidence. In agreement with traditional taxonomy, we recovered molecular support for a division between “sea butterflies” (Thecosomata; mucus-web feeders) and “sea angels” (Gymnosomata; active predators). Molecular dating demonstrated that these two lineages diverged in the early Cretaceous, and that all main pteropod clades, including shelled, partially-shelled, and unshelled groups, diverged in the mid- to late Cretaceous. Hence, these clades originated prior to and subsequently survived major global change events, including the Paleocene–Eocene Thermal Maximum (PETM), the closest analog to modern-day ocean acidification and warming. Our findings indicate that planktonic aragonitic calcifiers have shown resilience to perturbations in the Earth’s carbon cycle over evolutionary timescales.

翼足类动物是一组浮游腹足动物，被广泛认为是评估海洋酸化影响的生物指标。它们的文石壳对海洋化学的急剧变化高度敏感。然而，为了深入了解它们适应当前气候变化的潜力，我们需要准确地重建它们的进化历史并评估它们对地球碳循环过去变化的反应。在这里，我们利用系统发育数据集（2,654 个基因）解决了翼足类动物进化的系统发育和时间安排，其中包含 21 个翼足类动物物种的新数据和修订后的化石证据。与传统分类学一致，我们恢复了“海蝴蝶”（Thecosomata；粘液网饲养者）和“海天使”（Gymnosomata；活跃捕食者）之间划分的分子支持。分子测年表明，这两个谱系在白垩纪早期出现分歧，并且所有主要翼足类分支，包括带壳、部分带壳和无壳类群，在白垩纪中晚期出现分歧。因此，这些进化枝起源于重大全球变化事件之前并随后幸存下来，包括古新世-始新世最热事件（PETM），这是最接近现代海洋酸化和变暖的模拟。我们的研究结果表明，浮游文石钙化剂在进化时间尺度上表现出了对地球碳循环扰动的恢复能力。