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Background: The potential ecosystem collapse of forests in Mediterranean-type ecosystems (MTEs) by unprecedented droughts is worrisome due to the impacts on its exceptional biodiversity and human well-being. However, research integrating the impacts of global change drivers, forest resilience and the challenges facing human-nature relationships is still scarce. Methods and results: Using the central Chile megadrought and recently massive forest browning event as a model scenario, we identified, through a scientific literature review and an interdisciplinary scientific workshop, the research priorities and questions to address for MTEs in a context of global change. Our results highlighted knowledge gaps that need to be covered, particularly in social and environmental sciences, with an emphasis on soil science. Research priorities must focus on (1) the understanding of interactive effects of global and local anthropogenic drivers on MTEs and (2) the evaluation of the potential impacts of MTEs collapse on human well-being and ecosystem functioning. Conclusions: We highlight the need for a collaborative approach involving scientists, landowners, managers/administrators, and policymakers to apply adaptive forest management against the current socio-environmental challenges under a global change context. [ABSTRACT FROM AUTHOR]

BackgroundThe increase in availability of genomic sequences for a wide range of organisms has revealed gene duplication to be a relatively common event. Encounters with duplicate gene copies have consequently become almost inevitable in the context of collecting gene sequences for inferring species trees. Here we examine the effect of incorporating duplicate gene copies evolving at different rates on tree reconstruction and time estimation of recent and deep divergences in butterflies.ResultsSequences from ultraviolet-sensitive (UVRh), blue-sensitive (BRh), and long-wavelength sensitive (LWRh) opsins,EF-1α and COI were obtained from 27 taxa representing the five major butterfly families (5535 bp total). Both BRh and LWRh are present in multiple copies in some butterfly lineages and the different copies evolve at different rates. Regardless of the phylogenetic reconstruction method used, we found that analyses of combined data sets using either slower or faster evolving copies of duplicate genes resulted in a single topology in agreement with our current understanding of butterfly family relationships based on morphology and molecules. Interestingly, individual analyses of BRh and LWRh sequences also recovered these family-level relationships. Two different relaxed clock methods resulted in similar divergence time estimates at the shallower nodes in the tree, regardless of whether faster or slower evolving copies were used, with larger discrepancies observed at deeper nodes in the phylogeny. The time of divergence between the monarch butterfly Danaus plexippus and the queen D. gilippus (15.3–35.6 Mya) was found to be much older than the time of divergence between monarch co-mimic Limenitis archippus and red-spotted purple L. arthemis (4.7–13.6 Mya), and overlapping with the time of divergence of the co-mimetic passionflower butterflies Heliconius erato and H. melpomene (13.5–26.1 Mya). Our family-level results are congruent with recent estimates found in the literature and indicate an age of 84–113 million years for the divergence of all butterfly families.ConclusionThese results are consistent with diversification of the butterfly families following the radiation of angiosperms and suggest that some classes of opsin genes may be usefully employed for both phylogenetic reconstruction and divergence time estimation.

The process by which genes acquire new functions is not well understood, but gene duplication is considered an important mechanism for generating functional diversity. Gene duplications are often followed by an accelerated rate of evolution. We tested this hypothesis by examining the evolution of a pair of blue opsin duplicate genes in the butterfly genus Lycaena. Visual pigments are the light-sensitive molecules in the arthropods’ compound eye. The specific amino acid sequence of the opsin protein determines the peak absorption maximum of the visual pigment. We used PCR, cloning and sequencing of eye derived cDNAs to characterize all four opsin genes of L. heteronea and L. helloides, which we combined with the previously characterized L. rubidus opsin sequences. The translated opsin amino acid sequences were aligned and used to construct a phylogenetic tree. Each of these sequences falls within one of three well-supported clades in the insect opsin gene tree, comprised respectively of ultraviolet (UV), blue (B) and long-wavelength (LW) sensitive pigments. One of these genes belongs to the ultraviolet (UV) opsin clade, and encodes the visual pigment with peak sensitivity to 360 nm. A second gene clusters within the long wavelength (LW) clade and corresponds to the visual pigment with peak sensitivity to 568 nm. Two genes clustered within the blue-sensitive opsin clade (B1 and B2), representing respectively the visual pigments with peak sensitivity to 437 (blue) and 500 (green) nm. We used Tajima’s (1993) method to test whether or not the P500 opsin displayed an elevated rate of amino acid evolution following its divergence from the P437 opsin, which has a more typical peak sensitivity for opsins of that clade. Visual inspection of the branch lengths of the opsin tree suggested that B1 and B2 are evolving at different rates, and results from Tajima’s test support this finding for all three Lycaena species (p0.4), further suggesting that one of these genes has evolved a new function.

In a recent commentary, Nespolo (2003) makes reference to his personal experience as exattendant to the course of evolution imparted by Dr. Humberto Maturana and Dr. Jorge Mpodozis at the Facultad de Ciencias of the Universidad de Chile to construct a negative criticism of Chilean undergraduate teaching of evolution. As ex-attendants of the mentioned course of evolution we have had an experience that is directly comparable to that of Dr. Nespolo. Here we wish to point out our opinion regarding this course, which is markedly different. First, it is a caricature to state that in this course natural selection is taught as being wrong. A serious and critical revision of natural selection, the synthetic theory, and evolutionary ecology is a fundamental part of the course. These and other topics are presented by researchers from those fields, such as Drs. Germán Manríquez and Rodrigo Medel. The scientific contributions of both researchers receive positive comments in Nespolo (2003).

This document is a correction notice for an article titled "Unveiling emerging interdisciplinary research challenges in the highly threatened sclerophyllous forests of central Chile" published in the Revista Chilena de Historia Natural. The correction involves updating the affiliation details for Affiliation 7. The correct affiliation is the ESMOI-Center for Ecology and Sustainable Island Management in Coquimbo, Chile. The correction does not impact the overall findings or conclusions of the article. The publisher, Springer Nature, remains neutral regarding jurisdictional claims and institutional affiliations. The authors of the article are Cristian A. Delpiano, Solange Vargas, Juan F. Ovalle, Catalina Cáceres, Francisco Zorondo-Rodríguez, Alejandro Miranda, Nelida Pohl, Claudia Rojas, and Francisco A. Squeo. [Extracted from the article]