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Reply to Kardosh and Sklar: Prioritizing domain-general explanations of misperception
Reactive oxygen species–resistant ultrastable super-resolution DNA framework dots
Nanoconfinement as observed in natural (e.g. green fluorescent protein, GFP) or artificial (metal-organic or covalent organic frameworks) systems effectively modulates chemical and physical properties of encapsulated molecules for various photonic, electronic, or catalytic applications. Inspired by GFP’s barrel-like peptide scaffold, which stabilizes the chromophore within a confined space, here we develop photobleaching-resistant super-resolution DNA framework (SDF) dots that enables programmable confinement of various types of fluorophores within the inner cavity resembling GFP. We find that SDF dots are resistant to reactive oxygen species-induced photobleaching due to the shielding effects of DNA frameworks. SDF dots with four fluorophores labeling inside of the cavity leads to ~1.8-fold enhancement in photostability compared to the corner labeling, whereas ~50-fold enhancement compared to single fluorophore labeled on double-stranded DNA. These ultrastable SDF dots are readily adaptable for super-resolution imaging including stimulated emission depletion (STED) and structured illumination microscopy (SIM) imaging. We realize STED imaging of live cell membranes over 30 min. We further construct ultrastable super-resolution SIM barcodes that can distinguish eighteen colored barcodes with a spatial resolution of ~70 nm. This strategy provides a versatile platform for engineering ultrastable fluorescent probes for advancing super-resolution imaging and single-particle tracking in biophysics and biomedical research.
Correction for Camacho et al., Coral species from another ocean may be the only way to save Caribbean reefs
Glycosylation of glyphosate drives residue reduction and herbicide tolerance in rice
Glyphosate is the most widely used herbicide globally, especially due to the extensive cultivation of genetically modified glyphosate-resistant crops. However, its intensive application has raised public concerns about the risks to food safety and human health. Identifying enzymes capable of metabolizing glyphosate in plants represents an ideal strategy for addressing this issue, but few are known. Here, we identified the rice variety Kitaake with natural tolerance to glyphosate and demonstrated that this tolerance is driven by glyphosate glycosylation metabolism. Seven up-regulated UDP-dependent glycosyltransferase ( UGT ) genes associated with glyphosate tolerance were identified in Kitaake. Molecular-docking analysis indicated that these UGT proteins have moderate binding affinity for glyphosate. Among these, a deletion of an adenine at position –803 in the promoter region of GLYPHOSATE RESPONSIVE GLYCOSYLTRANSFERASE 1 ( GRGT1 ) enhances its expression in Kitaake. GRGT1 localizes to the endoplasmic reticulum and catalyzes glyphosate glycosylation both in vivo and in vitro. Rice lines complemented with GRGT1–GFP rescue the inability of grgt1 knockout mutants to produce glycosylated glyphosate derivatives. Overexpression of GRGT1 in the susceptible Nipponbare cultivar confers glyphosate tolerance by up-regulating glyphosate metabolism to produce glycosylated glyphosate derivatives M329, M331, and M345. This provides a strategy for developing herbicide-tolerant crops, but also offers a potential approach to consequently reduce glyphosate residues in crops.
Humans 40,000 y ago developed a system of conventional signs
As humans, we store and share information. This allows us to distribute knowledge necessary for survival and to coordinate large groups. Our hominin ancestors harnessed the surfaces of mobile artifacts and cave walls as information carriers since the Paleolithic time period. Theories abound as to the meaning and function of these Paleolithic signs. However, very little is known about their basic, measurable properties. We here analyze a corpus of more than 200 mobile objects of a 43,000 to 34,000 y old Aurignacian culture—associated with the first modern humans to settle in Central Europe. These objects are adorned with several thousand geometric signs. We apply classification algorithms and statistical models to capture their quantitative properties. First, our analyses illustrate that these sign sequences are clearly distinguishable from modern day writing. Second, however, their statistical properties are comparable to sign sequences on the earliest protocuneiform tablets. Third, Paleolithic signs were systematically applied to yield higher information density on certain types of objects, e.g. ivory figurines compared to tools. These results cannot be taken to strictly prove that Aurignacian sign sequences encoded numero-ideographic information as in the case of protocuneiform. However, they prove that the first hunter-gatherers arriving in Europe already applied sign sequences of comparable complexity in a deliberate, systematic, and conventional manner—several ten thousand years before the advent of genuine writing.
Social mobilizations for sustainability transformations
Overlooked and overexploited: Extensive conversion of grasslands and wetlands driven by global food, feed, and bioenergy demand
Natural ecosystems are increasingly threatened by global agricultural supply chains, and a narrow policy focus on forests has fueled agricultural expansion into ecologically significant but severely overlooked non-forest ecosystems, including grasslands and open wetlands. While a few emerging policies attempt to protect non-forest ecosystems, a globally consistent assessment of their conversion extent and drivers, especially related to livestock production and commodity-specific supply chain demand, remains lacking. Here, we conducted a spatially explicit analysis to identify pasture and cropland expansion into non-forest ecosystems between 2005 and 2020, as well as conversion-linked primary agricultural commodities and their underlying demand drivers (end uses and final market destinations). We found that the conversion rate of natural non-forest ecosystems was nearly four times that of lands with tree cover exceeding 5 m (a common forest height threshold), with Brazil contributing 13% of the global total and Russia, India, China, and the United States each contributing about 6%. While drivers varied greatly across regions, globally 50% of the conversion was linked to pasture, and 27, 17, and 6% to cropland for food, feed, and other uses (mainly bioenergy), respectively. Among conversion-linked commodities, most livestock-associated products served domestic demand, while 32% of feed crops and 20% of all crops were exported, with export shares reaching 70 to 80% in Brazil and Argentina. These findings reveal important areas for non-forest ecosystem conservation and highlight the need for integrated policies to prevent leakage across different ecosystems and different sustainable development goals while also aligning local actions with global supply chain governance.
Navigating the mysterious space of evolutionary histories
The way of life: The network challenge of blood flow in the brain
Studying adaptation at the invisible scale
In order to understand adaptation by natural selection, it is necessary to observe organisms in their natural habitat. For this reason, the field of behavioral ecology, which specializes in testing adaptive explanations for biological observations, is dominated by research on larger multicellular animals such as insects, mammals, fish, and birds. The vast majority of modern life sciences, however, is concerned with the study of cells, genes, and molecules, which are often impossible to observe directly in nature. This severely compromises our ability to complement mechanistic understand of traits of interest with adaptive understanding. This matters because only the theory of adaptation can provide an explanation for why biology operates in the way that it does, why it varies across individuals and species, a formal tool for making predictions about the future. The good news is that technological advances are creating new opportunities for understanding cellular and subcellular traits as the products of natural selection.
Phenotypic polymorphism via mate copying
Classical mate choice theories assume independent decision-making, yet mounting evidence shows that individuals often use social information and copy conspecifics’ mate choices, a behavior termed mate copying. While this nonindependent mate choice has been documented across vertebrates and notably in Drosophila melanogaster , theoretical and experimental frameworks have been mainly restricted to binary choice scenarios, limiting our understanding of its evolutionary implications in natural populations. Here, we develop a theoretical model of mate copying applicable to populations with multiple morphs, incorporating both private (inherent) and public (cultural) information in mate choice decisions. The population dynamics of the different male morphs are driven by the differing intensities of conformist and anticonformist mate copying. We demonstrate that mate copying can lead to the fixation of low-quality morphs and identify the conditions necessary for the existence of a polymorphism consisting of all male morphs in the population. Furthermore, we identify a plausible mechanism that could maintain a stable polymorphism in the case of conformist mate copying with two morphs. Our findings provide a theoretical framework for understanding how social learning in mate choice can influence evolutionary trajectories and contribute to maintaining phenotypic diversity in populations, with potential implications for sexual selection and speciation.
Structural and evolutionary constraints of organophosphate resistance in dipteran carboxylesterases
Enzymatic detoxification of organophosphate (OP) insecticides can confer resistance in some insects, yet the precise molecular basis of this trait, and how it has evolved, remains poorly understood. In certain dipteran species, a G→D mutation in the oxyanion hole of α-carboxylesterases (CBEs) enhances OP hydrolysis, yet this adaptation is not widespread despite the presence of orthologous CBEs in other insect species that are also exposed to OPs. The extent, and molecular basis, of evolutionary contingency and epistasis in this catalytic OP resistance has not been explored, and how further mutations might optimize OP detoxification in the future is not clear. Here, we systematically compare OP hydrolysis and analyze structures of CBE orthologs across several dipteran species, revealing that the success of the G137D mutation is sequence context-dependent. We employed laboratory-directed evolution to enhance OP turnover over 1,000-fold vs. the wildtype enzyme and tested these variants in transgenic Drosophila melanogaster , demonstrating that improved catalytic rates do not directly translate to increased resistance. By highlighting the trade-off between organophosphate affinity and turnover, this work further clarifies the complex evolutionary trajectories determining why a particular resistance mechanism may evolve in some species but not others.
The cognitive underpinnings of minority overestimation
Kava consumption and the rise of sociopolitical complexity in Oceania
Humans have been using psychoactive substances for millennia, despite their potential negative health and social consequences. According to some scholars, our craving for mind-altering drugs is an evolutionary mistake—a hijacking of our reward system. In contrast, the “drunk hypothesis” argues that intoxication has been adaptive and essential for the rise of large-scale societies because it promotes social bonding, increases cooperation, alleviates stress, and enhances human creativity. Here, we test this hypothesis using the example of kava, a traditional Pacific beverage with a range of psychoactive effects, made from the root of Piper methysticum . Our analysis of 83 Oceanic-speaking societies shows a positive relationship between traditional kava consumption and both political complexity and social stratification. However, the results are not robust to controls for nonindependence. Moreover, we found no evidence of coevolution between kava drinking and either of the two sociopolitical traits after controlling for spatial nonindependence. Despite the cultural significance of kava in many Pacific societies, our results suggest that its consumption was unlikely to have been a major driver of sociopolitical complexity, underscoring the importance of controlling for nonindependence in cross-cultural studies.
Tectonism rather than “snowball Earth” glaciation is responsible for the Great Unconformity
The Great Unconformity (GUn)—a widely recognized discontinuity and associated gap in the rock record between Precambrian and Cambrian rocks—represents a globally important interval of continental exposure and erosion that is notable also for the first appearance of all major animal phyla on Earth. However, its origin remains the subject of vigorous debate. Here, we present field relationships, and zircon and monazite U–Pb, biotite and muscovite Rb–Sr, and zircon (U–Th)/He thermochronology data for Precambrian crystalline basement rocks from North China to constrain the exhumation history below the unconformity. Dates from multichronometers and thermal history inversions show that the most substantial cooling of continental basement took place from ~2,100 to 1,600 Ma. Comparison with thermal history data from Laurentia, Baltica, and Amazonia suggests that protracted plate tectonics broadly modulated by supercontinent cycles, and not “snowball Earth” glaciation, is responsible for crustal exhumation below the unconformity. The most pronounced erosion evident in both the thermochronologic record and geochemical indicators of continental weathering is shown to correspond with development of Earth’s first true supercontinent (Columbia), rather than with either the Cambrian explosion or the emergence of modern plate tectonics.
Accelerated north–east shift of the global green wave trajectory
Viewed from space, a “green wave” seasonally traverses Earth’s surface, from the north in boreal summer to the south in austral summer. This wave represents vegetation phenology, driven primarily by solar irradiation and modulated by climate variability and ecosystem dynamics. Despite its significance for multiple Earth system processes, we lack a unified metric to characterize and understand its dynamics. Here, we propose a concept to quantify global phenology by tracking the green wave’s centroid using satellite and Earth system model data. The resulting trajectory summarizes global phenological dynamics and directional trends. Earlier reports on global greening led us to hypothesize a rapidly northward shifting trajectory during boreal summer and a moderate southward shift during austral summer. Contrary to this expectation, we find that the centroid moves northward during both summer periods, with the austral summer shift consistently exceeding the boreal shift across datasets. As a consequence, the amplitude of the green wave trajectory is decreasing, a trend projected to intensify throughout this century. We also detect an accelerating eastward shift, a phenomenon not previously reported. Tracking the green wave’s centroid reveals how regionally changing land dynamics affect the global functioning of Earth’s terrestrial biosphere.
Effects of correlated collisions and intermittency on the growth of lucky droplets
To trigger precipitation, water droplets in warm clouds need to attain a sufficient size. Theoretical estimates based on condensation and gravitational collisions alone fail to explain the observed timescales for the onset of precipitation for a range of droplet sizes. This suggests the involvement of collisional growth mediated by turbulence to resolve the so-called “size-gap problem.” For the onset of rain, it is sufficient that statistical outliers, coined “lucky droplets,” cross the size gap. In this study, we explore the influence of turbulence on droplet growth, focusing on correlated collisions and intermittency. Using direct numerical simulations of droplets in turbulent flow, we constrain a non-Markovian stochastic framework that allows us to assess memory effects on the droplet-size distribution arising from correlations between consecutive collisions. Using our framework, we find that correlated collisions accelerate the initial growth of lucky droplets but have subleading effect at later stages. Consequently, we neglect correlations from collisions and model an ensemble of cloud parcels representing fluctuations in the volume-averaged dissipation rate. Here, the distribution of droplet sizes in each parcel is described by a linear master equation with a time-dependent collision rate according to the volume-averaged dissipation rate. Our analyses of this toy model show that intermittency can significantly reduce the time required by lucky droplets to cross the size gap.