Schlenker Nora, Lee William G, Reichgelt Tammo, Ohlemüller Ralf
Department of Geography University of Wisconsin-Madison Madison Wisconsin USA.
Manaaki Whenua - Landcare Research Dunedin New Zealand.
Ecol Evol. 2024 Sep 3;14(9):e70133. doi: 10.1002/ece3.70133. eCollection 2024 Sep.
Past climate changes have had large impacts on modern ecological patterns. Understanding if legacies are distinguishable in the climatic niches of extant and locally extinct taxa can provide insight into the importance of climate in extinction events. To better understand mid- to late-Cenozoic New Zealand plant extinctions, which are often attributed to Cenozoic climate cooling, we identify 13 con-familial extinct and extant New Zealand genus pairs, which have modern distributions in Australia. Using climatic niches derived from current geographic distributions in Australia, we compared (i) total niche breadth, (ii) niche overlap, and (iii) individual climate parameters, to investigate potential climate drivers of intrafamilial extinction and persistence patterns in New Zealand. A majority of New Zealand extinct genera (9 out of 13 pairs) do not indicate climate niche legacies consistent with susceptibility to extinction from changing climates, while the remaining four extinct/extant pairs show slight climatic niche legacies. Three extinct genera have warmer niches than their extant counterpart, which is consistent with extinction reflecting intolerance of cooling Cenozoic climates. The other genus pair with a climatic niche legacy has an extinct genus that is distinguished by a niche with smaller precipitation seasonality than its extant counterpart, suggesting that climate metrics other than temperature may also be important extinction drivers in some taxa. Our results show that the mechanisms of Cenozoic extinctions of New Zealand genera are likely more complex than taxa reaching environmental tolerances due to cooling climates. Comparisons of current climatic niches between extant and extinct sister taxa can provide useful insights into large-scale, long-term climatic legacies but more analyses, including trait and phylogeographic patterns, would lead to additional insights into alternative pathways of extinction.
过去的气候变化对现代生态格局产生了重大影响。了解现存和本地灭绝类群的气候生态位中是否存在可区分的遗留特征，有助于洞察气候在灭绝事件中的重要性。为了更好地理解新西兰中新生代植物灭绝（这些灭绝事件常被归因于新生代气候变冷），我们识别出13对有亲缘关系的已灭绝和现存的新西兰属，它们在澳大利亚有现代分布。利用从澳大利亚当前地理分布得出的气候生态位，我们比较了：（i）总生态位宽度；（ii）生态位重叠；以及（iii）个体气候参数，以研究新西兰科内灭绝和存续模式的潜在气候驱动因素。大多数新西兰已灭绝属（13对中的9对）并未显示出与因气候变化而灭绝的易感性相一致的气候生态位遗留特征，而其余4对已灭绝/现存属对则显示出轻微的气候生态位遗留特征。三个已灭绝属的生态位比其现存对应属更温暖，这与灭绝反映出对新生代气候变冷的不耐受相一致。另一对具有气候生态位遗留特征的属中，已灭绝属的生态位特征是降水季节性比其现存对应属小，这表明除温度外的气候指标在某些类群中也可能是重要的灭绝驱动因素。我们的结果表明，新西兰属的新生代灭绝机制可能比因气候变冷导致类群达到环境耐受极限更为复杂。比较现存和已灭绝姐妹类群当前的气候生态位，可为大规模、长期的气候遗留特征提供有用见解，但更多分析，包括性状和系统地理学模式分析，将有助于深入了解灭绝的其他途径。
