Phylogenetic dimension of tree communities reveals high conservation value of disturbed tropical rain forests

Abstract

AimThe conversion of old‐growth tropical forests into human‐modified landscapes threatens biodiversity worldwide, but its impact on the phylogenetic dimension of remaining communities is still poorly known. Negative and neutral responses of tree phylogenetic diversity to land use change have been reported at local and landscape scales. Here, we hypothesized that such variable responses to disturbance depend on the regional context, being stronger in more degraded rain forest regions with a longer history of land use.LocationSix regions in Mexico and Brazil.MethodsWe used a large vegetation database (6,923 trees from 686 species) recorded in 98 50‐ha landscapes distributed across two Brazilian and four Mexican regions, which exhibit different degrees of disturbance. In each region, we assessed whether phylogenetic alpha and beta diversities were related to landscape‐scale forest loss, the percentage of shade‐intolerant species (a proxy of local disturbance) and/or the relatedness of decreasing (losers) and increasing (winners) taxa.ResultsContrary to our expectations, the percentage of forest cover and shade‐intolerant species were weakly related to phylogenetic alpha and beta diversities in all but one region. Loser species were generally as dispersed across the phylogeny as winner species, allowing more degraded, deforested and species‐poorer forests to sustain relatively high levels of evolutionary (phylogenetic) diversity.Main conclusionOur findings support previous evidence indicating that traits related to high susceptibility to forest disturbances are convergent or have low phylogenetic signal. More importantly, they reveal that the evolutionary value of disturbed forests is (at least in a phylogenetic sense) much greater than previously thought.

Phylogenetic signal in leaf-cutting ant diet in the fragmented Atlantic rain forest

“…When pioneer species are more related than late-successional species, their proliferation drives phylogenetic impoverishment of the forest (Norden et al 2012, Santos et al 2010, 2014. However, this is not always the case because not all fragmented forests lose tree phylogenetic diversity (Santo-Silva et al 2018). We conclude that by favouring or disfavouring specific phylogenetic clades via herbivory, LCA are key ecological players in the conversion of Neotropical old-growth forests into human-modified secondary forests.…”

Unraveling the drivers of plant taxonomic and phylogenetic β-diversity in a human-modified tropical dry forest

“…It is therefore likely that differences in cattle grazing activities (i.e., trampling, soil compaction and mineralization by deposition of urine and feces) among sites create heterogeneous environments that may affect seed germination and seedling recruitment, generating increases in β-diversity between sites (de Bello et al 2007). The fact that this pattern was not found when assessing dominant species (Table 1) suggests that plant traits (e.g., germination ability, desiccation tolerance, sprout ability) associated with vulnerability to extirpation in sites exposed to grazing activities are probably convergent or have low phylogenetic signal to dominant species (Santo- Silva et al 2018). However, this hypothesis needs to be tested in future studies.…”

“…3f, l). Interestingly, the fact that isolation distance showed a weaker effect on phylogenetic than on taxonomic β-diversity suggests that there may be a low phylogenetic signal in traits related to dispersal (Arroyo-Rodríguez et al 2012;Santo-Silva et al 2018)-a very important avenue for future research.…”

Soil niche of rain forest plant lineages: Implications for dominance on a global scale

“…Plant families were assigned to 120 Mya-old lineages, based on the dated phylogeny of Schneider et al (2004; dates using the strict application of crown group fossil age). This phylogeny is largely compatible with more specialized phylogenies for lycophytes (Wikström & Kenrick, 2001), pteridophytes (Rothfels et al, 2015), gymnosperms (Leslie et al, 2012), angiosperms (Magallón, Gómez-Acevedo, Sánchez-Reyes, & Hernández-Hernández, 2015), and vascular plants as a whole (Clarke, Warnock, & Donoghue, 2011). Consequently, we used the above-mentioned phylogenies to supplement data that were not available in Schneider et al (2004).…”

“…Different mangrove forest subtypes have different levels of exposure to seawater, creating microhabitats suitable for diverse animal and plant assemblages (Procheş, Marshall, Ugrasen, & Ramcharan, 2001;Satyanarayana et al, 2018). Secondary tropical forests are also interesting in terms of the lineages they harbour, having been shown to be essential in the conservation of plant phylogenetic diversity in the absence of primary forests (Santo-Silva et al, 2018). The Brunei Forestry Department provided the entry permit to access forest reserves ([21]/JPH/UBD/17 PT.1).…”