Niche overlap and divergence times support niche conservatism in eastern Asia–eastern North America disjunct plants

Abstract

Aim The plant species sharing ancestors now disjunctly distributed in eastern Asia (EAS) and eastern North America (ENA) have long been a biogeographic puzzle. Species within the EAS–ENA disjunct genera are presumed to exhibit niche conservatism, the tendency of closely related species to be more ecologically similar, reflecting lineages’ common evolutionary history. However, the hypothesis has not been well examined at the species level. Location EAS and ENA. Time period Current. Major taxa studied Species within the EAS–ENA disjunct genera. Methods We compiled data on climate, species occurrence, growth form, and phylogeny to examine niche conservatism. We first built a phylogenetic tree to select intercontinental congeneric pairwise species and obtained their divergence times. We then quantified the observed niche overlaps with Schoener’s D, which has a 0–1 range, based on species occurrence and climate of species’ native ranges. To obtain projected distributions, each species’ niche was projected to the non‐native region using ensemble ecological niche models. Projected‐related niche overlaps were then calculated using projected distributions and the corresponding climatic conditions. Results Average observed niche overlaps of congeneric pairwise species were relatively small: .124, .211 and .109 for all, herbaceous and woody species, respectively. Both observed and projected‐related niche overlaps had significant negative relationships with divergence times of intercontinental congeneric pairwise species, with niche overlap for herbaceous species being higher than that for woody plants when controlling for divergence times. Main conclusions We conclude that the significant negative relationships between niche overlap and divergence times of congeneric pairwise species confirm niche conservatism among species of EAS–ENA disjunct plants and that the extent of niche conservatism is slightly different for herbaceous and woody plants. These findings suggest the potential role of allopatric speciation in EAS, and could help to understand the evolutionary history and the Asian‐bias diversity pattern of the EAS–ENA disjunct plants.

Phylogenetic diversity of eastern Asia–eastern North America disjunct plants is mainly associated with divergence time

“…Moreover, temperature-related climatic factors were strongly correlated with SES-PD (Pearson's r = 0.815, p -value < 0.01), suggesting that SES-PD of the EA–ENA disjuncts may have been constrained by certain climatic conditions. A recent study revealed a negative correlation between climatic niche overlap and divergence times within the EA–ENA disjuncts, which also supports niche conservatism among those congeneric species pairs ( Yin et al., 2021 ).…”

“…As modern relicts of a once widespread flora across the Northern Hemisphere, the EA–ENA disjuncts are believed to be subject to niche conservatism, which is further interpreted as evolutionary stasis ( Wen, 1999 ; Qian and Ricklefs. 2004 ; Wen et al., 2010 ; Zhang et al., 2015 ; Yin et al., 2021 ). Apart from the evolutionary stasis in terms of morphology and geographical distribution, the present study provides insights into the niche conservatism of the EA–ENA disjuncts from a phylogenetic diversity perspective.…”

Large shifts of niche and range in the golden apple snail (Pomacea canaliculata), an aquatic invasive species

“…In other words, if the ecological niche conservatism hypothesis was rejected, the prediction based on ENMs may be misleading and may impair the efficient management against the invasions of AIS. However, until now this hypothesis remains debated, as some studies observed stable ecological niches of AIS in space and time (e.g., Gutierrez‐Ortega et al, 2020; Holt, 1996; Liu, Wolter, et al, 2020; Pearman et al, 2008; Yin et al, 2021), while others detected considerable niche shifts (e.g., Atwater et al, 2018; Loerch et al, 2021). Additionally, niche shifts in AIS may imply that they have adaptability to novel climates in the invasion processes, and AIS with stronger niche shifts may have higher invasion risk or potential.…”

Niche Divergence at Intraspecific Level in the Hyrcanian Wood Frog, Rana pseudodalmatina: A Phylogenetic, Climatic, and Environmental Survey

“…In recent decades, ecological factors have received increasing attention as a driver of lineage diversification and speciation (e.g., Wiens et al, 2010;Peterson, 2011;Broennimann et al, 2012;Zink, 2014;Hu et al, 2016;Fei et al, 2017;Wang et al, 2017;Gutiérrez-Ortega et al, 2020;Wei et al, 2020;Benício et al, 2021;Engler et al, 2021;Yin et al, 2021). In this debate, one of the main questions is whether newly developed species or clades exhibit signs of niche conservatism or divergence (Kozak and Wiens, 2006;Peterson, 2011;Wang et al, 2017;Zhu et al, 2020;Grossman, 2021;Meirmans, 2021;Van Dijk et al, 2021).…”