Are Cenozoic relict species also climatic relicts? Insights from the macroecological evolution of the giant sedges ofCarexsect.Rhynchocystis(Cyperaceae)

Abstract

Premise Most of the Paleotropical flora widely distributed in the Western Palearctic became extinct during the Mio‐Pliocene as a result of global geoclimatic changes. A few elements from this Cenozoic flora are believed to remain as relicts in Macaronesia, forming part of the laurel forests. Although the origins of the present species assembly are known to be heterogeneous, it is unclear whether some species should be considered climatic relicts with conserved niches. An ideal group for studying such relict characteristics is a Miocene lineage of Carex sect. Rhynchocystis (Cyperaceae), which comprises four species distributed in mainland Palearctic and Macaronesia. Methods We reconstructed the current and past environmental spaces for extant mainland and Macaronesian species, as well as for Pliocene fossils. We also studied the bioclimatic niche evolution. Species distribution modeling and ensemble small modeling were performed to assess the potential distribution over time. Results Climatic niche analyses and distribution modeling revealed that the ecological requirements of Macaronesian species did not overlap with those of either mainland species or with the Pliocene fossils. Conversely, the niches of mainland species displayed significant similarity and equivalence. Conclusions Macaronesian species are not climatic relicts from the Paleotropical flora, but instead seem to have changed the ecological niche of their ancestors. By contrast, despite their ancient divergence (Late Miocene), mainland C. pendula and C. agastachys show conserved niches, with competitive exclusion likely shaping their mostly allopatric ranges.

Repeated asynchronous evolution of single‐species endemics of ivies (Hedera L.) in Macaronesian archipelagos

“…A similar pattern is observed in other Macaronesian lineages ( Carex sect. Rhynchocystis , Sanz‐Arnal et al, 2022), where the climatic niche of island taxa is well differentiated from that of the extant mainland relatives.…”

“…In fact, although the broad climatic niche of H. helix also includes part of the niche of H. azorica (Figures 1 and 3), their overlap is low Rhynchocystis, Sanz-Arnal et al, 2022), where the climatic niche of island taxa is well differentiated from that of the extant mainland relatives.…”

RADseq‐based population genomic analysis and environmental adaptation of rare and endangered recretohalophyte Reaumuria trigyna

“…The occurrence of extreme events and impact of human activities have accelerated global environmental issues, further altering species distribution patterns (Cambronero et al., 2018). Loss of habitats threaten the ability of organisms to efficiently respond to environmental changes, leading to significant population decline as species with small ranges become vulnerable to extinction (Purvis et al., 2000; Sanz‐Arnal et al., 2022).…”

Predicting the potential impacts of climate change on the endangered endemic annonaceae species in east africa

“…Species Distribution Modeling (SDM) is a geographically explicit approach that integrates species occurrence data with environmental variables to produce spatially explicit and thorough maps that are useful for identifying regions that require the most conservation and management solutions [ 53 , 54 ]. SDM is a strong approach that has been used to predict past distributions of relict species in relevant regions, forecast their current prospective distribution range, and predict susceptibility to future climate change [ 55 ]. This model is valuable for anticipating conservation regions (particularly zones for species protection, restoration, translocation, and reintroductions) and for addressing questions about niche evolution trends [ 56 ].…”