Millennium Science Initiative

ABSTRACT Whether evolution follows predictable genetic paths across species remains a central question in evolutionary biology, particularly as rising temperatures reshape species distributions worldwide. Despite its importance, the genetic basis of thermal adaptation remains poorly understood across divergent species. Here, we use the yeast genus Saccharomyces as a comparative model to investigate how species with contrasting thermal niches adapt to rising temperatures. We combined experimental evolution under progressively increasing temperatures for up to ∼600 generations with whole-genome sequencing of 256 evolved genotypes, followed by transcriptomic, functional, and physiological analyses across eight species. Despite large differences in ancestral thermal tolerance and evolutionary outcomes, selection repeatedly targeted the same conserved regulatory pathways across species. Independent lineages accumulated de novo mutations in central growth and stress response networks, particularly in TORC1, PKA, and MAPK signaling pathways, revealing striking molecular convergence across species occupying distinct thermal environments. However, these shared genetic targets produced divergent transcriptional and physiological responses depending on species background, indicating that thermal adaptation primarily proceeds through rewiring of conserved regulatory hubs rather than changes in temperature-specific enzymes. Cold-tolerant species frequently lost mitochondrial DNA during thermal evolution, yet loss alone was insufficient to reproduce the adaptive thermal phenotypes of evolved populations. Together, our results show that adaptation to increasing temperature is driven by predictable changes in conserved regulatory networks, while species-specific constraints shape divergent phenotypic outcomes. These findings reveal both the predictability and contingency of evolutionary responses to rising temperature across species.

Abstract We present Keck/MOSFIRE H -band spectroscopic measurements covering the [C iii ] λ 1907, C iii ] λ 1909 doublet for a sample of eight z ∼ 7 spectroscopically confirmed star-forming galaxies drawn from the Reionization Era Bright Emission Line Survey (REBELS). This REBELS–MOSFIRE sample is notable for its bright median UV luminosity ( M UV = −22.5 AB) and large median stellar mass ( log M * / M ⊙ = 9.2 ). Although three sources show tentative evidence of a C iii ] detection, we obtain no confident detections for any of the eight REBELS–MOSFIRE sources. The median [C iii ] λ 1907+C iii ] λ 1909 3 σ upper limit in equivalent width (EW) for the REBELS–MOSFIRE sample is 6.5 Å, and a stack of their H -band MOSFIRE spectra yields a nondetection with an associated 3 σ upper limit of 2.6 Å. These upper limits fall significantly below the C iii ] EW measured in a composite spectrum of representative z ∼ 7 star-forming galaxies, as well as those measured for notable early star-forming galaxies such as GN-z11, GHZ2, GS-z12, and RXCJ2248-ID. The lack of strong C iii ] emission can be understood within the context of the stellar populations of the REBELS galaxies, as well as the ionization conditions and gas-phase metallicity implied by rest-frame optical spectroscopic properties ([O iii ]+H β EWs, and [O iii ] λ 5007/[O ii ] λ 3727 and [Ne iii ] λ 3869/[O ii ] λ 3727 line ratios). The REBELS–MOSFIRE sample represents the higher-mass, higher-metallicity, lower-excitation tail of the z ∼ 7 galaxy population, whose ionizing properties must be fully characterized to constrain the role of star-forming galaxies during cosmic reionization.

Abstract Stellar feedback drives multiphase gas outflows from starburst galaxies, but the interpretation of dust emission in these winds remains uncertain. To investigate this, we analyze new JWST mid-infrared images tracing polycyclic aromatic hydrocarbon (PAH) emission at 7.7 and 11.3 μ m from the outflow of the prototypical starburst M82 out to 3.2 kpc. We find that PAH emission shows significant correlations with CO, H α , and X-ray emission within the outflow, though the strengths and behaviors of these correlations vary with gas phase and distance from the starburst. PAH emission correlates strongly with cold molecular gas, with PAH–CO scaling relations in the wind nearly identical to those in galaxy disks despite the very different conditions. The H α –PAH correlation indicates that H α traces the surfaces of PAH-bearing clouds, consistent with arising from ionized layers produced by shocks. Meanwhile, the PAH–X-ray correlation disappears once distance effects are controlled for past 2 kpc, suggesting that PAHs are decoupled from the hot gas and the global correlation merely reflects the large-scale structure of the outflow. The PAH-to-neutral gas ratio remains nearly flat to 2 kpc, with variations following changes in the radiation field. This implies that the product of PAH abundance and dust-to-gas ratio does not change significantly over the inner portion of the outflow. Together, these results demonstrate that PAHs robustly trace the cold phase of M82’s wind, surviving well beyond the starburst and providing a powerful, high-resolution proxy for mapping the life cycle of entrained cold material in galactic outflows.

This article presents the findings of a qualitative study. It explores the influence of an androcentric logic and a neoliberal logic on the production of knowledge in a highly feminised field. Based on interviews with feminist disability researchers and activists in Latin America, we identify three interconnected elements that condition their academic work. These elements are associated with the structural spheres of operation of university institutions. In these institutions, binary gendered practices are (re)produced through the division of labour and the operation of a masculine rationality. There is also a disconnection between the processes of theorisation and the communities involved in them, along with practices of resistance and interruption of some of these dynamics. The results invite us to rethink academic practices from a feminist ethic of care and social justice, recognising and redistributing workloads, valuing emerging forms of knowledge at the frontier between academia and everyday life and contributing to the urgent call for a more inclusive and situated science committed to social transformation.

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental condition shaped by both genetic and environmental factors. While genetic studies have identified monogenic and polygenic contributions to ASD, growing evidence suggests that environmental exposures can modulate genetic susceptibility. Among these, bisphenol A (BPA), a widely studied endocrine-disrupting chemical, has drawn attention due to its ability to cross the blood-brain barrier and placenta. BPA can influence neurodevelopment through epigenetic modifications, mitochondrial dysfunction, and oxidative stress. Elevated BPA levels have been detected in serum and urine of individuals with ASD, correlating with altered gene expression in brain regions critical for cognition and behavior. Experimental models indicate that BPA exposure disrupts neuronal viability, synaptic connectivity, and neurotransmitter regulation, potentially exacerbating ASD-like phenotypes in genetically predisposed individuals. This review explores the interaction between genetic risk factors and environmental toxins, particularly BPA, in ASD pathogenesis. By integrating findings from epidemiological studies, molecular analyses, and animal models, we highlight the need for further research into gene-environment interactions to refine ASD risk assessment and therapeutic strategies.

Salmonid rickettsial septicemia (SRS) is an infectious disease caused by the marine bacterium Piscirickettsia salmonis. This Gamma-proteobacteria is a fastidious and facultative intracellular pathogen that has a nearly worldwide distribution, particularly impacting Chilean salmonid aquaculture. Its fastidious nature has made it hard to grow in labs, hindering research into its virulence and treatment, especially because of the lack of molecular techniques to study gene function. We show here the successful implementation of the Mobile-CRISPRi system for gene silencing. Significantly, we have adapted this technique for use with the marine pathogen P. salmonis, inserting exogenous genes into the bacterium's chromosome to ensure their constitutive and inducible expression and silencing both exogenous and endogenous gene expression. The Mobile-CRISPRi system was also used to study the iron regulator Fur, confirming Fur's relevance to the iron metabolism in the pathogen.

This research extends on Schelling’s dynamic models of segregation regarding on one of its basic rules: the individual tolerance of the agents in the network. Unlike previous applications that assume a homogeneous tolerance parameter for all individuals in the same population, this investigation introduces individual and distinctive tolerances for each agent, allowing for the exploration of more complex local dynamics and their effects on aggregate segregation. Through its implementation on a periodic two-dimensional lattice, local behaviors of instability and stability lead to less predictable segregation dynamics when comparing to Schelling’s original model. Whereas there is not a general rule that stems from individual tolerance thresholds for all the parametric space, an important characteristic emerges: that is, for given conditions in which extremely low tolerant agents interact, new efficient patterns of intragroup segregation emerges with size and geometries that intends to minimize the overall energy in the system.

ABSTRACTAntarctic marine sponges are essential components of the benthic fauna, playing a crucial role both through their own biological activities and their symbiotic relationships with diverse microorganisms. Yet, the transcriptional repertoire and the immune responses associated with interactions with microorganisms in this unique environment still need to be fully understood. Here, we investigated the transcriptional repertoire underlying the immune system processes of the Antarctic sponge Myxilla (Burtonanchora) lissostyla. We generated a de novo transcriptome and functional annotation for M. (B.) lissostyla, collected during the austral summer of 2019, 2020, and 2021. Our findings revealed an extensive transcriptional repertoire with a high and consistent expression of constitutive transcripts across the years. Key pathways related to immune response and homeostasis were the most expressed in the Antarctic sponge transcriptome, and a diverse array of immune receptors highlights the wide host immune repertoire. Low microbial abundance sponges share a vast repertoire of immune receptors, and a predominance of membrane‐bound PRRs was detected mainly in M. (B.) lissostyla, indicating a broad range of receptors available for initial interactions and engagement with microorganisms. The functional repertoire unveiled here establishes baselines for assessing potential functional changes that may arise due to climate change.