Effects of Pleistocene climate changes on species ranges and evolutionary processes in the Neotropical Atlantic Forest

Abstract

The effects of global glaciations on the distribution of organisms is an essential element of many diversification models. However, the empirical evidence supporting this idea is mixed, in particular with respect to explaining tropical forest evolution. In the present study, we evaluated the impacts of range shifts associated with Pleistocene global glacial cycles on the evolution of tropical forests. In particular, we tested the predictions: (1) that population genetic structure increases with fragmentation variation between the present and the Last Glacial Maximum (LGM) and also (2) with geographical range instability; and (3) that genetic diversity increases with range stability and (4) decreases with fragmentation variation between periods. To address our predictions, we studied population genetic structures and modelled present and past distributions of 15 Atlantic Forest (AF) endemic birds. Afterwards, we evaluated the relationship of population genetic parameters with metrics of species range shifts between the present and the LGM. We found that geographical ranges of AF birds changed in concert with Pleistocene glacial cycles but, unexpectedly, our findings suggest the novel idea that ranges during glacial maxima were slightly larger on average, as well as equally fragmented and displaced from the interglacial ranges. Our findings suggest that range shifts over the late Pleistocene impacted on the diversification of forest organisms, although they did not show that those range shifts had a strong effect. We found that a combination of fragmentation variation across time, small current range size, and range stability increased population genetic structure. However, neither fragmentation, nor range stability affected genetic diversity. Our study showed that evolutionary responses to range shifts across AF birds have a high variance, which could explain the mixed support given by single‐species studies to the action of Pleistocene range shifts on population evolution.

Isolation by instability: Historical climate change shapes population structure and genomic divergence of treefrogs in the Neotropical Cerrado savanna

“…The Cerrado savanna is a global hotspot of biodiversity in South America, but it is only recently that the evolutionary and ecological drivers of diversification in this savanna have been investigated (Simon et al, ; Werneck, ). Here, we demonstrate that past climatic fluctuations were important in driving intraspecific genetic structure in this habitat as has already been demonstrated for the Atlantic Forest (Cabanne et al, ; Carnaval et al, ). Genetic differentiation in Hypsiboas lundii was positively correlated with the climatic instability resistance among populations, a metric based on the persistence of populations across time using past predictions of species distribution models over the late Quaternary.…”

“…The climatic fluctuations of Pleistocene glacial cycles have greatly impacted the distribution of organisms, imprinting on their populations a genetic signature of such changes (Davis & Shaw, ; Hewitt, ). Even though the genetic consequences of the ice ages are well documented for many organisms in the Northern Hemisphere (Hewitt, ), less evidence exists for the Southern Hemisphere (but see Cabanne et al, ), possibly due to the reduced extent of glaciations in this region. Although glaciers covered only small portions of South America, most notably in the extreme southern region and in the Andes (Ehlers, Gibbard, & Hugues, ; Vuilleumier, ), cycles of contraction and expansion of forests and savannas during glacial and interglacial periods are thought to have occurred (Van der Hammen, ) and to have significantly affected vegetation structure and distribution of organisms throughout the continent (Bonaccorso, Koch, & Peterson, ; Saia, Pessenda, Gouveia, Aravena, & Bendassolli, ).…”

Estimating synchronous demographic changes across populations using hABC and its application for a herpetological community from northeastern Brazil

“…In contrast to the expansion of Caatinga and dry‐adapted taxa, population contraction is expected for species restricted to wet forest enclaves and adjacent continuous wet forest from northeastern Brazil. Interestingly, recent studies suggest population contraction of wet forest‐dwelling reptiles and birds in Northern Atlantic Forest (NAF) and Eastern Amazonia (EAM; Cabanne et al., ; Prates et al., ).…”

Spatial variability in species' potential distributions during the Last Glacial Maximum under different Global Circulation Models: Relevance in evolutionary biology

“…Ecological niche models (ENM) are increasingly used to estimate climate‐driven range shifts across the Quaternary (Araújo & Peterson, ; Elith & Leathwick, ; Martínez‐Meyer, Peterson, & Hargrove, ). These geographic predictions may help assess distributional shifts that likely occurred during glacial/interglacial cycles, which are useful for testing evolutionary hypotheses about the processes generating actual distributional patterns (Cabanne et al., ; Carnaval, Hickerson, Haddad, Rodrigues, & Moritz, ; Collevatti et al., ; Guevara, Gerstner, Kass, & Anderson, ). More commonly, ENM are used to reconstruct geographic distributions during the Last Glacial Maximum (LGM, ~ 21 kyr bp ), one of the episodes that have had a major impact on the evolutionary history of extant species (Hewitt, ), allowing to speculate whether the climate during the LGM have led to fragmentation, connectivity, extinction, or population expansion (Alvarado‐Serrano & Knowles, ; Peterson & Lieberman, ).…”

“…Ecological niche models (ENM) are increasingly used to estimate climate-driven range shifts across the Quaternary (Araújo & Peterson, 2012;Elith & Leathwick, 2009;Martínez-Meyer, Peterson, & Hargrove, 2004). These geographic predictions may help assess distributional shifts that likely occurred during glacial/interglacial cycles, which are useful for testing evolutionary hypotheses about the processes generating actual distributional patterns (Cabanne et al, 2016;Carnaval, Hickerson, Haddad, Rodrigues, & Moritz, 2009;Collevatti et al, 2013;Guevara, Gerstner, Kass, & Anderson, 2018).…”