Science Enabled by Specimen Data

岛屿因具有明确的地理边界, 是检验多个生态学过程如何构建生物多样性的理想平台之一。岛屿属性、气候因素、人 类干扰等通过影响物种选择、扩散等过程, 进而影响着岛屿生物多样性格局。目前对于岛屿植物丰富度格局如何受这些因素 的共同作用的认识仍不充分, 尤其是在人类干扰较强的海岛。本文基于我国第一大群岛舟山群岛92个岛屿较完整的种子植物 分布数据, 采用一般线性回归和广义线性模型(伪泊松分布)定量评估岛屿属性(面积、隔离度、形状指数)、气候(温度、降水 及其季节性)和人类干扰对本土植物总丰富度及不同生长型、叶物候型植物丰富度格局的影响, 采用beta回归分析常绿阔叶木 本比率(常绿阔叶木本植物丰富度/所有阔叶木本植物丰富度)的影响因素。结果发现: 92个岛屿共记录本土植物1,158种, 其中 乔木108种、灌木318种、草本732种; 岛屿面积是对植物总丰富度影响最大的因子, 其次是年降水量和隔离度; 乔木丰富度随 隔离度增加而减少的趋势比灌木和草本更明显; 常绿阔叶和落叶阔叶木本植物丰富度格局与总体基本一致, 年降水量对常绿 阔叶木本的影响大于落叶阔叶木本, 但常绿阔叶木本比率仅受温度季节性的强烈影响。岛屿面积、年降水量、温度季节性等 是塑造舟山群岛所有植物及其不同功能型组(生长型、叶物候型)植物丰富度格局的主要决定因素。

Metreveli, V., H. Kreft, I. Akobia, Z. Janiashvili, Z. Nonashvili, L. Dzadzamia, Z. Javakhishvili, and A. Gavashelishvili. 2023. Potential Distribution and Suitable Habitat for Chestnut (Castanea sativa). Forests 14: 2076. https://doi.org/10.3390/f14102076

Chestnut, Castanea sativa Miller (Fagales: Fagaceae), is an ecologically and economically important tree species of the forest ecosystem in Southern Europe, North-Western Europe, Western Asia, North Africa, and the Caucasus. The distributional range of chestnut in Europe has been highly modified by humans since ancient times. Biotic and abiotic factors have dramatically changed its distribution. Historic anthropogenic range expansion makes it difficult to identify habitat requirements for natural stands of chestnut. In the Caucasus, natural stands of chestnut survived in glacial forest refugia and landscapes that have been difficult for humans to colonize. To identify the species reliable habitat requirements, we estimated the relationship between climatic variables and 620 occurrence locations of natural chestnut stands from the Caucasus and validated the model using GBIF data from outside the Caucasus. We found that our best model is reasonably accurate and the data from the Caucasus characterize chestnut stands throughout the species range well.

Wan, Q., K. Huang, S.-F. Chen, F. Boyer, P. Taberlet, H. Li, C. Chen, et al. 2023. Fagus diversification in China in relation to East Asian monsoon evolution. Quaternary Science Reviews 320: 108350. https://doi.org/10.1016/j.quascirev.2023.108350

When and how the extraordinary species diversity in subtropical East Asia formed is intensely debated, and the available evidence is often inconsistent. In this study, we evaluate the effects of pre- and post- Quaternary events on the evolutionary and biogeographic history of Chinese beech (Fagus species that now occur in China) to gain new insights into the historical establishment and future fate of the East Asian subtropical forest (EASF). A series of approaches and datasets were used to reconstruct biogeographic and evolutionary history of the Chinese beech. They include phylogeography based on the polymorphisms of the complete chloroplast genomes, species distribution models, and a large palaeobiogeographic dataset including 59 pre-Quaternary fossil records, 296 Quaternary fossil records and 3515 modern pollen records. Our multidisciplinary approach suggests that (i) Chinese beech has dispersed to subtropical East Asia and diversified in the early Miocene when the Asian monsoon (AM) intensified; (ii) the last post-glacial warming resulted in limited poleward displacement but significant contraction at southern and lower elevations; (iii) the poleward dispersal of Chinese beech was limited by drought in the early growing season in temperate China, controlled by the East Asian summer monsoon. Our results support the hypothesis that the establishment of the EASF is closely related to the evolution of the AM. More importantly, we suggest that with continued climate warming (e.g., during the last post-glacial period or under current climate change), the monsoon probably hindered rather than promoted the persistence of deciduous beech species, resulting in a decline in species richness.

Jin, D., Q. Yuan, X. Dai, G. Kozlowski, and Y. Song. 2023. Enhanced precipitation has driven the evolution of subtropical evergreen broad‐leaved forests in eastern China since the early Miocene: Evidence from ring‐cupped oaks. Journal of Systematics and Evolution. https://doi.org/10.1111/jse.13022

Subtropical evergreen broad‐leaved forest (EBLF) is the predominant vegetation type in eastern China. However, the majority of the region it covers in eastern China was an arid area during the Paleogene. The temporal history and essential factors involved in the evolution of subtropical EBLFs in eastern China remain enigmatic. Here we report on the niche evolution of Quercus section Cyclobalanopsis, which appeared in south China and Japan during the Eocene and became a dominant component of subtropical EBLFs since the Miocene in eastern Asia, using integrative analysis of occurrences, climate data and a dated phylogeny of 35 species in Cyclobalanopsis. Species within clades Cyclobalanoides, Lamellosa, and Helferiana mainly exist in the Himalaya–Hengduan region, adapting to a plateau climate, while species within the other clades mainly live in eastern China under the control of the East Asian monsoon. Reconstructed history showed that significant divergence of climatic tolerance in Cyclobalanopsis began around 19 million years ago (Ma) in the early Miocene. Simultaneously, disparities in precipitation of wettest/warmest quarter and annual precipitation were markedly enhanced in Cyclobalanopsis, especially in the recent eastern clades. During the Miocene, the marked radiation of Cyclobalanopsis and many other dominant taxa of subtropical EBLFs strongly suggest the rapid formation and expansion of subtropical EBLFs in eastern China. Our research highlights that the intensification of the East Asian monsoon and subsequent occupation of new niches by the ancient clades already present in the south may have jointly promoted the formation of subtropical EBLFs in eastern China since the early Miocene.

Calvente, A., A. P. Alves da Silva, D. Edler, F. A. Carvalho, M. R. Fantinati, A. Zizka, and A. Antonelli. 2023. Spiny but photogenic: amateur sightings complement herbarium specimens to reveal the bioregions of cacti. American Journal of Botany. https://doi.org/10.1002/ajb2.16235

Premise: Cacti are characteristic elements of the Neotropical flora and of major interest for biogeographic, evolutionary, and ecological studies. Here we test global biogeographic boundaries for Neotropical Cactaceae using specimen‐based occurrences coupled with data from visual observations, as a means to tackle the known collection biases in the family.MethodsSpecies richness and record density were assessed for preserved specimens and human observations and a bioregional scheme tailored to Cactaceae was produced using the interactive web application Infomap Bioregions based on data from 261,272 point records cleaned through automated and manual steps.Key ResultsWe find that areas in Mexico and southwestern USA, Eastern Brazil and along the Andean region have the greatest density of records and the highest species richness. Human observations complement information from preserved specimens substantially, especially along the Andes. We propose 24 cacti bioregions, among which the most species‐rich are: northern Mexico/southwestern USA, central Mexico, southern central Mexico, Central America, Mexican Pacific coast, central and southern Andes, northwestern Mexico/extreme southwestern USA, southwestern Bolivia, northeastern Brazil, Mexico/Baja California.ConclusionsThe bioregionalization proposed shows biogeographical boundaries specific to cacti, and can thereby aid further evolutionary, biogeographic, and ecological studies by providing a validated framework for further analyses. This classification builds upon, and is distinctive from, other expert‐derived regionalization schemes for other taxa. Our results showcase how observation data, including citizen‐science records, can complement traditional specimen‐based data for biogeographic research, particularly for taxa with specific specimen collection and preservation challenges and those that are threatened or internationally protected.This article is protected by copyright. All rights reserved.

Maurin, O., A. Anest, F. Forest, I. Turner, R. L. Barrett, R. C. Cowan, L. Wang, et al. 2023. Drift in the tropics: Phylogenetics and biogeographical patterns in Combretaceae. Global Ecology and Biogeography. https://doi.org/10.1111/geb.13737

Aim The aim of this study was to further advance our understanding of the species-rich, and ecologically important angiosperm family Combretaceae to provide new insights into their evolutionary history. We assessed phylogenetic relationships in the family using target capture data and produced a dated phylogenetic tree to assess fruit dispersal modes and patterns of distribution. Location Tropical and subtropical regions. Time Period Cretaceous to present. Major Taxa Studied Family Combretaceae is a member of the rosid clade and comprises 10 genera and more than 500 species, predominantly assigned to genera Combretum and Terminalia, and occurring on all continents and in a wide range of ecosystems. Methods We use a target capture approach and the Angiosperms353 universal probes to reconstruct a robust dated phylogenetic tree for the family. This phylogenetic framework, combined with seed dispersal traits, biome data and biogeographic ranges, allows the reconstruction of the biogeographical history of the group. Results Ancestral range reconstructions suggest a Gondwanan origin (Africa/South America), with several intercontinental dispersals within the family and few transitions between biomes. Relative abundance of fruit dispersal types differed by both continent and biome. However, intercontinental colonizations were only significantly enhanced by water dispersal (drift fruit), and there was no evidence that seed dispersal modes influenced biome shifts. Main Conclusions Our analysis reveals a paradox as drift fruit greatly enhanced dispersal distances at intercontinental scale but did not affect the strong biome conservatism observed.

Poore, C., N. A. Jud, and M. A. Gandolfo. 2023. Fossil fruits from the early Paleocene of Patagonia, Argentina reveal west Gondwanan history of Icacinaceae. Review of Palaeobotany and Palynology: 104940. https://doi.org/10.1016/j.revpalbo.2023.104940

Phytocreneae (Icacinaceae) are a tribe of climbing plants distributed throughout tropical Afro-Eurasia and Papua New Guinea. There is a rich Cenozoic fossil record of the group with occurrences on all continents except Antarctica. Fossil evidence supports a Cretaceous origin but the biogeographic history of Phytocreneae remains unclear. We examined a silicified endocarp collected from the Danian (early Paleocene) Salamanca Formation at the Estancia Las Violetas locality. We investigated the internal structure using micro-CT scanning and compared the fossil with fruits of other living and fossil species. Finally, we explored the biogeographic history of the tribe graphically and discuss the implications of this discovery. The endocarp belongs to the fossil genus Palaeophytocrene. This new occurrence significantly expands the known geographic range of Phytocreneae in South America. Furthermore, this is the oldest (ca. 63 Ma) unequivocal evidence of the tribe in the southern hemisphere. The presence of Phytocreneae at Estancia Las Violetas confirms that these lianas occurred in mid-latitude forests by the early Paleocene, and it also reveals that the tribe likely survived the end-Cretaceous extinction event in southern South America. Future work on the tribe should include filling gaps in the Gondwanan record to test the hypothesis that Australasian lineages are related to American lineages via high-latitude dispersal.

Chen, L., G. Kadereit, and M. C. Veranso-Libalah. 2023. Combining Angiosperms353 and Sanger data provides support for the reinstatement of the genus Myrianthemum (Melastomataceae). Botanical Journal of the Linnean Society. https://doi.org/10.1093/botlinnean/boad024

Abstract The increasing availability of DNA sequence data, in particular target enrichment data based on the universal Angiosperms353 probe set, but also accumulated Sanger data from previous phylogenetic studies, is facilitating the placement of taxa that are difficult to place with certainty based on morphological evidence alone. Here, we investigate phylogenetic relationships of Medinilla mirabilis (Melastomataceae), a species distributed in central Africa and currently classified in the mega-diverse genus Medinilla of tribe Sonerileae. Medinilla mirabilis is a twining liana with verticillate leaves when young, spherical inflorescences, 4-merous flowers, dimorphic stamens, and baccate fruits. Our results revealed that M. mirabilis is sister to tribe Dissochaeteae and only distantly related to Medinilla. We also provide new data on wood anatomical and seed morphological characters of M. mirabilis. The alternate inter-vessel pits in M. mirabilis and Dissochaeteae are consistent with the phylogenetic placement. Seeds of M. mirabilis are similar to those of Dissochaeteae and of Medinilla. Due to its unique morphology and phylogenetic position, we propose to reinstate the monospecific genus Myrianthemum with Myrianthemum mirabile. This necessitates expansion of the Southeast Asian tribe Dissochaeteae to include Myrianthemum as its only African member. Our study of M. mirabile demonstrates that the combined application of Angiosperms353 and Sanger data is a cost-effective approach to phylogenetically place enigmatic taxa.

Pang, S. E. H., J. W. F. Slik, D. Zurell, and E. L. Webb. 2023. The clustering of spatially associated species unravels patterns in tropical tree species distributions. Ecosphere 14. https://doi.org/10.1002/ecs2.4589

Complex distribution data can be summarized by grouping species with similar or overlapping distributions to unravel spatial patterns and separate trends (e.g., of habitat loss) among spatially unique groups. However, such classifications are often heuristic, lacking the transparency, objectivity, and data‐driven rigor of quantitative methods, which limits their interpretability and utility. Here, we develop and illustrate the clustering of spatially associated species, a methodological framework aimed at statistically classifying species using explicit measures of interspecific spatial association. We investigate several association indices and clustering algorithms and show how these methodological choices drive substantial variations in clustering outcomes and performance. To facilitate robust decision‐making, we provide guidance on choosing methods appropriate to one's study objective(s). As a case study, we apply our framework to modeled tree distributions in Borneo and subsequently evaluate the impact of land‐cover change on separate species groupings. Based on the modeled distribution of 390 tree species prior to anthropogenic land‐cover changes, we identified 11 distinct clusters that unraveled ecologically meaningful patterns in Bornean tree distributions. These clusters then enabled us to quantify trends of habitat loss tied to each of those specific clusters, allowing us to discern particularly vulnerable species clusters and their distributions. This study demonstrates the advantages of adopting quantitatively derived clusters of spatially associated species and elucidates the potential of resultant clusters as a spatially explicit framework for investigating distribution‐related questions in ecology, biogeography, and conservation. By adopting our methodological framework and publicly available codes, practitioners can leverage the ever‐growing abundance of distribution data to better understand complex spatial patterns among species distributions and the disparate effects of global changes on biodiversity.

Wilf, P., and R. M. Kooyman. 2023. Do Southeast Asia’s paleo‐Antarctic trees cool the planet? New Phytologist. https://doi.org/10.1111/nph.19067

Many tree genera in the Malesian uplands have Southern Hemisphere origins, often supported by austral fossil records. Weathering the vast bedrock exposures in the everwet Malesian tropics may have consumed sufficient atmospheric CO2 to contribute significantly to global cooling over the past 15 Myr. However, there has been no discussion of how the distinctive regional tree assemblages may have enhanced weathering and contributed to this process. We postulate that Gondwanan‐sourced tree lineages that can dominate higher‐elevation forests played an overlooked role in the Neogene CO2 drawdown that led to the Ice Ages and the current, now‐precarious climate state. Moreover, several historically abundant conifers in Araucariaceae and Podocarpaceae are likely to have made an outsized contribution through soil acidification that increases weathering. If the widespread destruction of Malesian lowland forests continues to spread into the uplands, the losses will threaten unique austral plant assemblages and, if our hypothesis is correct, a carbon sequestration engine that could contribute to cooler planetary conditions far into the future. Immediate effects include the spread of heat islands, significant losses of biomass carbon and forest‐dependent biodiversity, erosion of watershed values, and the destruction of tens of millions of years of evolutionary history.