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1.
Proc Biol Sci ; 291(2018): 20232840, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38471557

RESUMO

Scientific knowledge is produced in multiple languages but is predominantly published in English. This practice creates a language barrier to generate and transfer scientific knowledge between communities with diverse linguistic backgrounds, hindering the ability of scholars and communities to address global challenges and achieve diversity and equity in science, technology, engineering and mathematics (STEM). To overcome those barriers, publishers and journals should provide a fair system that supports non-native English speakers and disseminates knowledge across the globe. We surveyed policies of 736 journals in biological sciences to assess their linguistic inclusivity, identify predictors of inclusivity, and propose actions to overcome language barriers in academic publishing. Our assessment revealed a grim landscape where most journals were making minimal efforts to overcome language barriers. The impact factor of journals was negatively associated with adopting a number of inclusive policies whereas ownership by a scientific society tended to have a positive association. Contrary to our expectations, the proportion of both open access articles and editors based in non-English speaking countries did not have a major positive association with the adoption of linguistically inclusive policies. We proposed a set of actions to overcome language barriers in academic publishing, including the renegotiation of power dynamics between publishers and editorial boards.


Assuntos
Disciplinas das Ciências Biológicas , Editoração , Idioma , Linguística
2.
Artigo em Inglês | MEDLINE | ID: mdl-37848246

RESUMO

The significance of prezygotic isolation for speciation has been recognized at least since the Modern Synthesis. However, fundamental questions remain. For example, how are genetic associations between traits that contribute to prezygotic isolation maintained? What is the source of genetic variation underlying the evolution of these traits? And how do prezygotic barriers affect patterns of gene flow? We address these questions by reviewing genetic features shared across plants and animals that influence prezygotic isolation. Emerging technologies increasingly enable the identification and functional characterization of the genes involved, allowing us to test established theoretical expectations. Embedding these genes in their developmental context will allow further predictions about what constrains the evolution of prezygotic isolation. Ongoing improvements in statistical and computational tools will reveal how pre- and postzygotic isolation may differ in how they influence gene flow across the genome. Finally, we highlight opportunities for progress by combining theory with appropriate data.


Assuntos
Plantas , Isolamento Reprodutivo , Animais , Plantas/genética , Especiação Genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-38151330

RESUMO

How barriers to gene flow arise and are maintained are key questions in evolutionary biology. Speciation research has mainly focused on barriers that occur either before mating or after zygote formation. In comparison, postmating prezygotic (PMPZ) isolation-a barrier that acts after gamete release but before zygote formation-is less frequently investigated but may hold a unique role in generating biodiversity. Here we discuss the distinctive features of PMPZ isolation, including the primary drivers and molecular mechanisms underpinning PMPZ isolation. We then present the first comprehensive survey of PMPZ isolation research, revealing that it is a widespread form of prezygotic isolation across eukaryotes. The survey also exposes obstacles in studying PMPZ isolation, in part attributable to the challenges involved in directly measuring PMPZ isolation and uncovering its causal mechanisms. Finally, we identify outstanding knowledge gaps and provide recommendations for improving future research on PMPZ isolation. This will allow us to better understand the nature of this often-neglected reproductive barrier and its contribution to speciation.

4.
Elife ; 102021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34280087

RESUMO

In Heliconius butterflies, wing colour pattern diversity and scale types are controlled by a few genes of large effect that regulate colour pattern switches between morphs and species across a large mimetic radiation. One of these genes, cortex, has been repeatedly associated with colour pattern evolution in butterflies. Here we carried out CRISPR knockouts in multiple Heliconius species and show that cortex is a major determinant of scale cell identity. Chromatin accessibility profiling and introgression scans identified cis-regulatory regions associated with discrete phenotypic switches. CRISPR perturbation of these regions in black hindwing genotypes recreated a yellow bar, revealing their spatially limited activity. In the H. melpomene/timareta lineage, the candidate CRE from yellow-barred phenotype morphs is interrupted by a transposable element, suggesting that cis-regulatory structural variation underlies these mimetic adaptations. Our work shows that cortex functionally controls scale colour fate and that its cis-regulatory regions control a phenotypic switch in a modular and pattern-specific fashion.


Heliconius butterflies have bright patterns on their wings that tell potential predators that they are toxic. As a result, predators learn to avoid eating them. Over time, unrelated species of butterflies have evolved similar patterns to avoid predation through a process known as Müllerian mimicry. Worldwide, there are over 180,000 species of butterflies and moths, most of which have different wing patterns. How do genes create this pattern diversity? And do butterflies use similar genes to create similar wing patterns? One of the genes involved in creating wing patterns is called cortex. This gene has a large region of DNA around it that does not code for proteins, but instead, controls whether cortex is on or off in different parts of the wing. Changes in this non-coding region can act like switches, turning regions of the wing into different colours and creating complex patterns, but it is unclear how these switches have evolved. Butterfly wings get their colour from tiny structures called scales, which each have their own unique set of pigments. In Heliconius butterflies, there are three types of scales: yellow/white scales, black scales, and red/orange/brown scales. Livraghi et al. used a DNA editing technique called CRISPR to find out whether the cortex gene affects scale type. First, Livraghi et al. confirmed that deleting cortex turned black and red scales yellow. Next, they used the same technique to manipulate the non-coding DNA around the cortex gene to see the effect on the wing pattern. This manipulation turned a black-winged butterfly into a butterfly with a yellow wing band, a pattern that occurs naturally in Heliconius butterflies. The next step was to find the mutation responsible for the appearance of yellow wing bands in nature. It turns out that a bit of extra genetic code, derived from so-called 'jumping genes', had inserted itself into the non-coding DNA around the cortex gene, 'flipping' the switch and leading to the appearance of the yellow scales. Genetic information contains the instructions to generate shape and form in most organisms. These instructions evolve over millions of years, creating everything from bacteria to blue whales. Butterfly wings are visual evidence of evolution, but the way their genes create new patterns isn't specific to butterflies. Understanding wing patterns can help researchers to learn how genetic switches control diversity across other species too.


Assuntos
Borboletas/genética , Pigmentos Biológicos/genética , Asas de Animais/fisiologia , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Cor , Fenótipo
5.
Mol Biol Evol ; 38(11): 4805-4821, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34254128

RESUMO

Parallel evolution of ecotypes occurs when selection independently drives the evolution of similar traits across similar environments. The multiple origins of ecotypes are often inferred based on a phylogeny that clusters populations according to geographic location and not by the environment they occupy. However, the use of phylogenies to infer parallel evolution in closely related populations is problematic because gene flow and incomplete lineage sorting can uncouple the genetic structure at neutral markers from the colonization history of populations. Here, we demonstrate multiple origins within ecotypes of an Australian wildflower, Senecio lautus. We observed strong genetic structure as well as phylogenetic clustering by geography and show that this is unlikely due to gene flow between parapatric ecotypes, which was surprisingly low. We further confirm this analytically by demonstrating that phylogenetic distortion due to gene flow often requires higher levels of migration than those observed in S. lautus. Our results imply that selection can repeatedly create similar phenotypes despite the perceived homogenizing effects of gene flow.


Assuntos
Ecótipo , Senécio , Austrália , Fluxo Gênico , Filogenia , Senécio/genética
6.
Evolution ; 75(2): 555-556, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33350465

RESUMO

Are the distributions of mountain species shifting up or downslope under climate change? Contrary to the long-held view of global warming forcing an upslope shift of montane ecosystems, Salces-Castellano et al. found that populations of a beetle tightly associated to cloud forests were isolated through the ice ages but in contact during interglacial periods, suggesting downslope shifts of cloud forest when temperature increases.


Assuntos
Fluxo Gênico , Árvores , Mudança Climática , Ecossistema , Florestas
7.
Acta biol. colomb ; 21(1): 167-173, Jan.-Apr. 2016. ilus, tab
Artigo em Inglês | LILACS | ID: lil-769043

RESUMO

Biological collections in natural history museums serve important purposes to the scientific community and the general public, however, their value and utility might be diminished by biodeterioration. We studied a biological collection that represents more than sixty years of avifauna sampling of Colombia, the country with the highest bird diversity. An initial inspection of the collection showed that the general appearance of some specimens was compromised by mold-like growth on their surfaces. We aimed at (i) identifying the taxonomic affiliation of these fungi, (ii) evaluating their cellulolytic activity, and (iii) probing chemical agents that could be utilized to control their growth. The most common fungi genera were Aspergillus, Penicillium, Chaetomium, and Trichophyton, most of which can degrade cellulose. Zinc chloride and salicylic acid showed to be effective fungicides. Based on this, we propose some actions to control the fungi-pest in this biological collection of birds.


Las colecciones biológicas en los museos de historia natural juegan un papel importante tanto para la comunidad cientifica como para el público en general. Sin embargo, su valor y utilidad pueden verse afectados por la biodeterioración de sus ejemplares. Se estudio una colección biológica de aves que representa más de sesenta anos de esfuerzo de muestreo de la avifauna del pais más rico en aves. Una inspección inicial mostró que la apariencia general de algunos de los especimenes de la colección se encontraba afectada por hongos. Los objetivos de este estudio fueron (i) identificar la afiliación taxonómica de los hongos, (ii) determinar la actividad celulolítica y (iii) probar agentes químicos que puedan ser utilizados para controlar su desarrollo. Los géneros de hongos más comunes fueron Aspergillus, Penicillium, Chaetomium y Trichophyton, de los cuales la mayoria presentan la capacidad de degradar celulosa. Adicionalmente, el cloruro de zinc y el ácido salicilico actuaron como fungicidas efectivos. De acuerdo con en estos resultados proponemos algunas acciones para controlar la contaminación por hongos en la colección de aves.

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