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Hamilton's theory [1] for the evolution of social behaviour predicts that helpers may renounce direct reproduction to help their more fertile kin. Intra-colony recognition among queens and helpers (subordinate queens or workers) is consequently a central issue in insect sociobiology. In social insects, cuticular hydrocarbons (CHCs) are involved in recognition, and egg-laying and non-egg-laying individuals often differ in CHC composition. These differences are assumed to be directly determined by fertility status [2,3]. In several ants and in Polistes wasps, when egg-layers disappear they are substituted by helpers, which develop their ovaries and become chemically similar to their former queens [2,3]. Sometimes helpers lay eggs in the presence of queens, which recognize and destroy the subordinates' eggs [4]. In ponerine ants, eggs often have the same chemical signature as the maternal cuticle [2]. If chemical signatures depend on fertility, egg-laying subordinates should match the queen's signature even when she is present, making egg recognition and differential oophagy impossible. In the study reported here, we experimentally separated fertility from dominance and analyzed the dynamics of hydrocarbon profiles of the cuticle of Polistes dominulus foundresses and the shell surface of their eggs. We have demonstrated that, contrary to the widely accepted view, dominance, rather than fertility, determines chemical signatures in Polistes wasps. This explains why queens can recognize their own eggs and police reproduction by subordinates if they become fertile and lay eggs.

The ability to recognize others is a frequent assumption of models of the evolution of cooperation. At the same time, cooperative behavior has been proposed as a selective agent favoring the evolution of individual recognition abilities. Although theory predicts that recognition and cooperation may co-evolve, data linking recognition abilities and cooperative behavior with evidence of selection are elusive. Here, we provide evidence of a selective link between individual recognition and cooperation in the paper wasp Polistes fuscatus through a combination of clinal, common garden, and population genomics analyses. We identified latitudinal clines in both rates of cooperative nesting and color pattern diversity, consistent with a selective link between recognition and cooperation. In behavioral experiments, we replicated previous results demonstrating individual recognition in cooperative and phenotypically diverse P. fuscatus from New York. In contrast, wasps from a less cooperative and phenotypically uniform Louisiana population showed no evidence of individual recognition. In a common garden experiment, groups of wasps from northern populations formed more stable and individually biased associations, indicating that recognition facilitates group stability. The strength of recent positive selection on cognition-associated loci likely to mediate individual recognition is substantially greater in northern compared with southern P. fuscatus populations. Collectively, these data suggest that individual recognition and cooperative nesting behavior have co-evolved in P. fuscatus because recognition helps stabilize social groups. This work provides evidence of a specific cognitive phenotype under selection because of social interactions, supporting the idea that social behavior can be a key driver of cognitive evolution., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Regenerative organisms such as plants must have specific signals that respond to damage and instruct remnant tissue to undergo repair. A recent paper identifies a long-sought candidate for the signal that links injury to regenerative programs., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

In 1973, two papers from Bliss and Lømo and from Bliss and Gardner-Medwin reported that high-frequency synaptic stimulation in the dentate gyrus of rabbits resulted in a long-lasting increase in synaptic strength. This form of synaptic plasticity, commonly referred to as long-term potentiation (LTP), was immediately considered as an attractive mechanism accounting for the ability of the brain to store information. In this historical piece looking back over the past 50 years, we discuss how these two landmark contributions directly motivated a colossal research effort and detail some of the resulting milestones that have shaped our evolving understanding of the molecular and cellular underpinnings of LTP. We highlight the main features of LTP, cover key experiments that defined its induction and expression mechanisms, and outline the evidence supporting a potential role of LTP in learning and memory. We also briefly explore some ramifications of LTP on network stability, consider current limitations of LTP as a model of associative memory, and entertain future research orientations., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024. Published by Elsevier Inc.)

The Mps1 and Aurora B kinases regulate and monitor kinetochore attachment to spindle microtubules during cell division, ultimately ensuring accurate chromosome segregation. In yeast, the critical spindle attachment components are the Ndc80 and Dam1 complexes (Ndc80c and DASH/Dam1c, respectively). Ndc80c is a 600-Å-long heterotetramer that binds microtubules through a globular "head" at one end and centromere-proximal kinetochore components through a globular knob at the other end. Dam1c is a heterodecamer that forms a ring of 16-17 protomers around the shaft of the single kinetochore microtubule in point-centromere yeast. The ring coordinates the approximately eight Ndc80c rods per kinetochore. In published work, we showed that a site on the globular "head" of Ndc80c, including residues from both Ndc80 and Nuf2, binds a bipartite segment in the long C-terminal extension of Dam1. Results reported here show, both by in vitro binding experiments and by crystal structure determination, that the same site binds a conserved segment in the long N-terminal extension of Mps1. It also binds, less tightly, a conserved segment in the N-terminal extension of Ipl1 (yeast Aurora B). Together with results from experiments in yeast cells and from biochemical assays reported in two accompanying papers, the structures and graded affinities identify a communication hub for ensuring uniform bipolar attachment and for signaling anaphase onset., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Tardigrades withstand ionizing irradiation levels ∼500 times higher than humans can tolerate. Two recent papers shed light on how this might be achieved - via the transcriptional induction of DNA repair genes, the induction of a radioprotective DNA-binding protein, and possibly also the heightened capacity of repair proteins., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

A new paper shows that rates of aggression are higher, and rates of coalition formation are lower, among male bonobos than among male chimpanzees. These findings are noteworthy because they challenge the view that female bonobos' preferences for less aggressive males favored a reduction in male aggression and an increase in social tolerance., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Bacterial genomes often harbor integrated viruses (prophages), which provide novel functions but also lyse cells under stressful conditions. A new paper combines mathematical models with experimental evolution to determine how prophages are maintained in bacterial populations despite their fitness costs., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024. Published by Elsevier Inc.)

Understanding the evolution and subsequent maintenance of ecological diversity is a daunting task. Using a historical microbial evolution experiment, a new paper demonstrates the extent to which diversity can re-emerge in reduced communities and the traits through which rediversification occurs., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Cephalopod molluscs are renowned for their unique central nervous system - a donut-shaped brain organised around the oesophagus. This brain supports sophisticated learning and memory abilities. Between the 1950s and 1980s, these cognitive abilities were extensively studied in octopus (Figure 1A) - a now leading model for the study of memory and its neural substrates (approximately 200 papers during this period). The focus on octopus learning and memory was mainly due to their curious nature and the fact that they adapt to laboratory-controlled conditions, making them easy to test and maintain in captivity. Research on cephalopod cognition began to widen in the late 20th century, when scientists started focusing on other coleoid cephalopods (i.e., cuttlefish and squid) (Figure 1B,C), and not just on associative learning and memory per se, but other more complex aspects of cognition such as episodic-like memory (the ability to remember the what, where, and when of a past event), source memory (the retrieval of contextual details from a memory), and self-control (the ability to inhibit an action in the present to gain a more valuable future reward). Attention broadened further over the last two decades to focus on the shelled cephalopods - the nautiloids (Figure 1D). The nautiloids have relatively primitive brains compared to their soft-bodied cousins (octopus, cuttlefish, and squid) but research shows that they are still able to comparatively succeed in some cognitive tasks. In this primer, we will provide a general description of the types of memory studied in cephalopods, and discuss learning and memory experiments that address the main challenges cephalopods face during their daily lives: navigation, timing, and food selection. Determining the type of information cephalopods learn and remember and whether they use such information to overcome ecological challenges will highlight why these invertebrates evolved large and sophisticated brains., Competing Interests: Declaration of interests The authors declare no competing interests., (Crown Copyright © 2023. Published by Elsevier Inc. All rights reserved.)

According to Newton's laws, the weight of a body part is equal to its mass times gravitational acceleration. Our experience of body part weight, however, is constructed by the central nervous system. No sensory receptors directly specify the weight of body parts, and the factors influencing perceived weight remain unknown. The perceived weight of held objects has been linked to sensations of the magnitude of central motor commands sent to the muscles, what Helmholtz called the effort of will and has subsequently been called the sense of effort 1 . The link between the sense of effort and the perceived weight of objects is shown by studies demonstrating that held weights feel heavier when muscles are weakened by fatigue 1 , anaesthesia 2 , and following brain damage 3 . Similar drive to muscles is required to counteract the force of gravity on the limbs themselves, though few studies have investigated the perceived weight of body parts 4 . Stroke patients with hemiplegia frequently comment that their limbs feel heavy 5 , an effect linked to fatigue in the affected limb 6 . Similarly, amputees commonly complain of the weight of prosthetic limbs 7 , despite these typically weighing less than actual limbs. Here we report that healthy adult humans systematically underestimate hand weight. We used a psychophysical matching task to measure the experience of hand weight, which was underestimated on average by 49.4%. We further found that experimental induction of hand fatigue causes a systematic increase in perceived hand weight. Our results demonstrate that humans fail to experience the full weight of their body., Competing Interests: Author contributions E.R.F. and M.R.L. conceived the study and designed the experiments. All authors constructed equipment. J.J. and D.C. collected the data. All authors analysed the data. E.R.F. and M.R.L. wrote the paper. All authors approved the final version of the paper. The editors of Current Biology welcome correspondence on any article in the journal, but reserve the right to reduce the length of any letter to be published. All correspondence containing data or scientific argument will be refereed. Queries about articles for consideration in this format should be sent by e-mail to cbiol@current-biology.com, (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Serotonin signaling is conserved in regulating animal behaviors. A new paper decodes the nonlinear effects of all serotonin receptor combinations on foraging behaviors. The authors introduce a brain-wide multiscale method to dissect receptor dynamics, receptor effects on neural activity, and resulting behavioral changes., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Amidst a global biodiversity crisis 1 , the word 'biodiversity' has become indispensable for conservation and management 2 . Yet, biodiversity is often used as a buzzword in scientific literature. Resonant titles of papers claiming to have studied 'global biodiversity' may be used to promote research focused on a few taxonomic groups, habitats, or facets of biodiversity - taxonomic, (phylo)genetic, or functional. This usage may lead to extrapolating results outside the target systems of these studies with direct consequences for our understanding of life on Earth and its practical conservation. Here, we used a random sample of papers with the word 'biodiversity' in their title to take a long view of the use of this term. Despite improvements in analytical tools, monitoring technologies, and data availability 3 , 4 , we found that the taxonomic scope of research articles has not increased in recent years. We also show that studies with a wider taxonomic scope attract more citations and online attention. Our results have broad ramifications for understanding how extrapolating from studies with narrow taxonomic scope affects our view of global biodiversity and conservation., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Cephalopods' eyes superficially resemble our own, but because of their evolutionary and developmental history, the photoreceptors face forward, with the downstream neural circuitry in the brain, not the retina. Two new papers uncover molecular and developmental mechanisms underlying cephalopod visual development., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Corals have long been known to generate local fluid flows using ciliary beating, but the importance of these ciliary flows is just being discovered. Two new papers shed light on how ciliary-flow physics plays a key role in shaping coral physiology., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

How does tissue elongation occur? A recent paper identifies a new mechanism: elongation of the Caenorhabditis elegans hermaphrodite gonad is driven by pressure from proliferating germ cells confined within a tube. The distal tip cell, which caps the tube, remodels the extracellular matrix and adjusts cell-matrix adhesion to guide the way., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

A recent paper suggests that the flatworm Schmidtea mediterranea has an autosome that is 'primed' to evolve into a sex chromosome. However, this chromosome could be a balanced-lethal system and may illuminate these puzzling systems., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The complicated arbors of neuronal dendrites and axons host synapses, the sites of information transfer and storage. A new paper describes how an important synaptic molecule, Calcium-calmodulin protein kinase 2, gets concentrated at synapses and how its local synthesis is important for memory in the fruit fly., Competing Interests: Declaration of interests The author declares no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Making sense of the metabolism of microbial communities is a daunting task. Using denitrification as a model metabolism, a new paper shows that the rate of denitrification can often be predicted from genome contents, and dynamical models can be composed to predict denitrification rates of communities of two to five species., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Wolbachia is a genus of globally distributed endosymbiotic bacteria found in thousands of species of arthropods and nematodes. One strain, wMel, has spread globally but varies dramatically in frequency. In a new paper, Hague et al. discovered that the interaction of host genotype, symbiont genotype, and environment explains natural wMel variation., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Traditionally, paleontologists have relied on the morphological features of bones and teeth to reconstruct the evolutionary relationships of extinct animals. 1 In recent decades, the analysis of ancient DNA recovered from macrofossils has provided a powerful means to evaluate these hypotheses and develop novel phylogenetic models. 2 Although a great deal of life history data can be extracted from bones, their scarcity and associated biases limit their information potential. The paleontological record of Beringia 3 -the unglaciated areas and former land bridge between northeast Eurasia and northwest North America-is relatively robust thanks to its perennially frozen ground favoring fossil preservation. 4 , 5 However, even here, the macrofossil record is significantly lacking in small-bodied fauna (e.g., rodents and birds), whereas questions related to migration and extirpation, even among well-studied taxa, remain crudely resolved. The growing sophistication of ancient environmental DNA (eDNA) methods have allowed for the identification of species within terrestrial/aquatic ecosystems, 6-12 in paleodietary reconstructions, 13-19 and facilitated genomic reconstructions from cave contexts. 8 , 20-22 Murchie et al. 6 , 23 used a capture enrichment approach to sequence a diverse range of faunal and floral DNA from permafrost silts deposited during the Pleistocene-Holocene transition. 24 Here, we expand on their work with the mitogenomic assembly and phylogenetic placement of Equus caballus (caballine horse), Bison priscus (steppe bison), Mammuthus primigenius (woolly mammoth), and Lagopus lagopus (willow ptarmigan) eDNA from multiple permafrost cores spanning the last 40,000 years. We identify a diverse metagenomic spectra of Pleistocene fauna and identify the eDNA co-occurrence of distinct Eurasian and American mitogenomic lineages., Competing Interests: Declaration of interests T.J.M., H.N.P., and R.D.E.M. are members of the CANA Foundation science advisory board, a non-profit organization with horse re-wilding initiatives. T.J.M. and H.N.P. are currently supported by CANA through a PDF to T.J.M. and consumable costs. The research presented in this paper was completed long prior to funding by CANA. The authors declare no other competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The cell cortex, comprised of the plasma membrane and underlying cytoskeleton, undergoes dynamic reorganizations during a variety of essential biological processes including cell adhesion, cell migration, and cell division. 1 , 2 During cell division and cell locomotion, for example, waves of filamentous-actin (F-actin) assembly and disassembly develop in the cell cortex in a process termed "cortical excitability." 3-7 In this paper, we develop an artificial cortex based on Xenopus egg extract and supported lipid bilayers (SLBs), to investigate cortical Rho and F-actin dynamics. 7 , 8 These feedback loops are proposed to serve as a mechanism for amplification of active Rho signaling at the cell equator to support furrowing during cytokinesis while also maintaining flexibility for rapid error correction in response to movement of the mitotic spindle during chromosome segregation. 9 In this paper, we develop an artificial cortex based on Xenopus egg extract and supported lipid bilayers (SLBs), to investigate cortical Rho and F-actin dynamics. 10 This reconstituted system spontaneously develops two distinct types of self-organized cortical dynamics: singular excitable Rho and F-actin waves, and non-traveling oscillatory Rho and F-actin patches. Both types of dynamic patterns have properties and dependencies similar to the excitable dynamics previously characterized in vivo. 7 These findings directly support the long-standing speculation that the cell cortex is a self-organizing structure and present a novel approach for investigating mechanisms of Rho-GTPase-mediated cortical dynamics., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The Great Barrier Reef has become one of the latest casualties of the climate crisis, suffering mass coral mortalities following three marine heat waves since 2016. Two new papers untangle the cumulative effects of these disturbances on the reef's resilience., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Eye movements are an integral part of human visual perception. They allow us to have a small foveal region with exquisite acuity and at the same time a large visual field. For a long time, eye movements were regarded as machine-like behaviors in response to visual stimulation 1 , but over the past few decades it has been convincingly shown that expectations, intended actions, rewards and many other cognitive factors can have profound effects on the way we move our eyes 2-4 . In order to be useful, our oculomotor system must minimize delay with respect to the dynamic events in the visual scene. The ability to do so has been demonstrated in situations where we are in control of these events, for example when we are making a sandwich or tea 5 , and when we are active participants, for example when hitting a cricket ball 6 . But what about scenes with complex dynamics that we do not control or directly take part in, like a hockey game we are watching as a spectator? A semantic influence on gaze fixation location during viewing of tennis videos has been suggested before 7 . Here we use carefully annotated hockey videos to show that the brain is indeed able to exploit the semantic context of the game to anticipate the continuous motion of the puck, leading to eye movements that are fundamentally different than when following exactly the same motion without any context., Competing Interests: Declaration of interests Two authors of this paper are founders and shareholders of the company AttentiveVision (www.attentivevision.com), which owns the datasets from which the data used for this paper were drawn., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

The fossil record reveals rampant extinction. However, analyses of time-calibrated molecular phylogenies often find no extinction at all. A new paper shows that estimates of zero extinction are entirely incorrect and are caused by limitations of analysing phylogenies that sample only living species., (Crown Copyright © 2021. Published by Elsevier Inc. All rights reserved.)

Controlling aggression is a crucial skill in social species like rodents and humans and has been associated with anterior cingulate cortex (ACC). Here, we directly link the failed regulation of aggression in BALB/cJ mice to ACC hypofunction. We first show that ACC in BALB/cJ mice is structurally degraded: neuron density is decreased, with pervasive neuron death and reactive astroglia. Gene-set enrichment analysis suggested that this process is driven by neuronal degeneration, which then triggers toxic astrogliosis. cFos expression across ACC indicated functional consequences: during aggressive encounters, ACC was engaged in control mice, but not BALB/cJ mice. Chemogenetically activating ACC during aggressive encounters drastically suppressed pathological aggression but left species-typical aggression intact. The network effects of our chemogenetic perturbation suggest that this behavioral rescue is mediated by suppression of amygdala and hypothalamus and activation of mediodorsal thalamus. Together, these findings highlight the central role of ACC in curbing pathological aggression., Competing Interests: Declaration of interests J.K.B. was a consultant to/member of advisory board of/and/or speaker for Janssen-Cilag BV, Eli Lilly, Takeda (Shire), Medice, Roche, and Servier. J.C.G. has in the past 4 years been a consultant to Boehringer Ingelheim GmbH. Neither J.K.B. nor J.C.G. are employees of any of these companies, and neither are stock shareholders of any of these companies. The funding organizations or industrial consultancies listed have had no involvement with the conception, design, data analysis and interpretation, review, and/or any other aspects relating to this paper. The remaining authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)

In a new paper in this issue, Murawski and Brynildsen define chromosomal ploidy as an important characteristic for persistence following fluoroquinolone treatment. Bacteria carrying two chromosomes are more likely to repair DNA damage through homologous recombination compared with cells containing a single chromosome., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Oomycetes are notorious plant pathogens. It is known that genetically distinct oomycete strains can mate to increase their genetic diversity and virulence. A new paper finally reveals the genomic locus that may govern sexual compatibility in one oomycete species., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Seminal studies using squid as a model led to breakthroughs in neurobiology. The squid giant axon and synapse, for example, laid the foundation for our current understanding of the action potential [1], ionic gradients across cells [2], voltage-dependent ion channels [3], molecular motors [4-7], and synaptic transmission [8-11]. Despite their anatomical advantages, the use of squid as a model receded over the past several decades as investigators turned to genetically tractable systems. Recently, however, two key advances have made it possible to develop techniques for the genetic manipulation of squid. The first is the CRISPR-Cas9 system for targeted gene disruption, a largely species-agnostic method [12, 13]. The second is the sequencing of genomes for several cephalopod species [14-16]. If made genetically tractable, squid and other cephalopods offer a wealth of biological novelties that could spur discovery. Within invertebrates, not only do they possess by far the largest brains, they also express the most sophisticated behaviors [17]. In this paper, we demonstrate efficient gene knockout in the squid Doryteuthis pealeii using CRISPR-Cas9. Ommochromes, the pigments found in squid retinas and chromatophores, are derivatives of tryptophan, and the first committed step in their synthesis is normally catalyzed by Tryptophan 2,3 Dioxygenase (TDO [18-20]). Knocking out TDO in squid embryos efficiently eliminated pigmentation. By precisely timing CRISPR-Cas9 delivery during early development, the degree of pigmentation could be finely controlled. Genotyping revealed knockout efficiencies routinely greater than 90%. This study represents a critical advancement toward making squid genetically tractable., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Tracking the outcomes of third-party social interactions is a vital social skill but thought to be cognitively complicated. Paper wasps can learn about others' fighting abilities from observation, suggesting surprisingly complex understanding of social networks in a miniature brain., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The development of lateral roots requires multiple mechanisms that act together for accurate spatiotemporal emergence of the new organ. A new paper shows how cell death in overlying endodermis cells contributes to the formation of new lateral root primordia., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Creating microbial consortia capable of consistently producing desired qualities requires a detailed understanding of community interactions. A new paper demonstrates the role of historical contingency in Arabidopsis thaliana leaf-microbiome formation using an adaptable experimental approach, which could be applied to other host organisms., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Unlike juveniles, adult animals engage in suites of behaviors related to the search for and selection of potential mates and mating, including appropriate responses to sex pheromones. As in other species [1], male sex pheromones modulate several behaviors and physiological processes in C. elegans hermaphrodites [2-5]. In particular, one of these small-molecule signals, an ascaroside ascr#10, causes reduced exploration, more avid mating, and improved reproductive performance (see the accompanying paper by Aprison and Ruvinsky in this issue of Current Biology) [6]. Here, we investigated the mechanism that restricts pheromone response to adult hermaphrodites. Unexpectedly, we found that attainment of developmental adulthood was not alone sufficient for the behavioral response to the pheromone. To modify exploratory behavior in response to male pheromone, adult hermaphrodites also require functional germline and egg-laying apparatus. We show that this dependence of behavior on the reproductive system is due to feedback from the vulva muscles that reports ongoing reproduction to the nervous system. Our results reveal an activity-dependent conduit by which the reproductive system continuously licenses adult behaviors, including appropriate responses to the pheromones of the opposite sex. More broadly, our results suggest that signals from peripheral organs may serve as an important component of assuring age-appropriate functions of the nervous system., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A recent paper demonstrates how tissue context impacts the breast cancer cell phenotype. Loss of the E-cadherin tumor suppressor protein enhanced cell invasion, but inhibited multiple steps in metastatic spread due to the accumulation of reactive oxygen species and induction of apoptosis., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In angiosperms, two sperm cells are transported and delivered by the pollen tube to the ovule to achieve double fertilization. Extensive communication takes place between the pollen tube and the female tissues until the sperm cell cargo is ultimately released. During this process, a pollen tube surface-located receptor complex composed of ANXUR1/2 (ANX1/2) and Buddha's Paper Seal 1/2 (BUPS1/2) was reported to control the maintenance of pollen tube integrity by perceiving the autocrine peptide ligands rapid alkalinization factor 4 and 19 (RALF4/19). It was further hypothesized that pollen-tube rupture to release sperm is caused by the paracrine RALF34 peptide from the ovule interfering with this signaling pathway. In this study, we identified two Arabidopsis pollen-tube-expressed glycosylphosphatidylinositol-anchored proteins (GPI-APs), LORELEI-like-GPI-anchored protein 2 (LLG2) and LLG3, as co-receptors in the BUPS-ANX receptor complex. llg2 llg3 double mutants exhibit severe fertility defects. Mutant pollen tubes rupture early during the pollination process. Furthermore, LLG2 and LLG3 interact with ectodomains of both BUPSs and ANXURs, and this interaction is remarkably enhanced by the presence of RALF4/19 peptides. We further demonstrate that the N terminus (including a YISY motif) of the RALF4 peptide ligand interacts strongly with BUPS-ANX receptors but weakly with LLGs and is essential for its biological function, and its C-terminal region is sufficient for LLG binding. In conclusion, we propose that LLG2/3 serve as co-receptors during BUPS/ANX-RALF signaling and thereby further establish the importance of GPI-APs as key regulators in plant reproduction processes., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

To counter their widespread loss, global aspirations are for no net loss of remaining wetlands [1]. We examine whether this goal alone is sufficient for managing China's wetlands, for they constitute 10% of the world's total. Analyzing wetland changes between 2000 and 2015 using 30-m-resolution satellite images, we show that China's wetlands expanded by 27,614 km 2 but lost 26,066 km 2 -a net increase of 1,548 km 2 (or 0.4%). This net change hides considerable complexities in the types of wetlands created and destroyed. The area of open water surface increased by 9,110 km 2 , but natural wetlands-henceforth "marshes"-decreased by 7,562 km 2 . Of the expanded wetlands, restoration policies contributed 24.5% and dam construction contributed 20.8%. Climate change accounted for 23.6% but is likely to involve a transient increase due to melting glaciers. Of the lost wetlands, agricultural and urban expansion contributed 47.7% and 13.8%, respectively. The increase in wetlands from conservation efforts (6,765 km 2 ) did not offset human-caused wetland losses (16,032 km 2 ). The wetland changes may harm wildlife. The wetland loss in east China threatens bird migration across eastern Asia [2]. Open water from dam construction flooded the original habitats of threatened terrestrial species and affected aquatic species by fragmenting wetland habitats [3]. Thus, the "no net loss" target measures total changes without considering changes in composition and the corresponding ecological functions. It may result in "paper offsets" and should be used carefully as a target for wetland conservation., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Two new papers show how deep neural networks interacting with the brain can generate visual images that drive surprisingly strong neural responses. These images are tantalizing reflections of visual information in the brain., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In 1979, Daniel Kahneman and Amos Tversky published a ground-breaking paper titled "Prospect Theory: An Analysis of Decision under Risk," which presented a behavioral economic theory that accounted for the ways in which humans deviate from economists' normative workhorse model, Expected Utility Theory [1, 2]. For example, people exhibit probability distortion (they overweight low probabilities), loss aversion (losses loom larger than gains), and reference dependence (outcomes are evaluated as gains or losses relative to an internal reference point). We found that rats exhibited many of these same biases, using a task in which rats chose between guaranteed and probabilistic rewards. However, prospect theory assumes stable preferences in the absence of learning, an assumption at odds with alternative frameworks such as animal learning theory and reinforcement learning [3-7]. Rats also exhibited trial history effects, consistent with ongoing learning. A reinforcement learning model in which state-action values were updated by the subjective value of outcomes according to prospect theory reproduced rats' nonlinear utility and probability weighting functions and also captured trial-by-trial learning dynamics., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Two recent papers demonstrate that the 'tubulin code' - the pattern of chemical modifications of tubulin along a microtubule - is disrupted upon deletion or mutation of an enzyme, called CCP1, that removes one of these modifications. Ablation of CCP1 interferes with mitochondrial transport and causes human neurodegenerative disease, which may be amenable to pharmacological therapies., (Copyright © 2018 Elsevier Ltd. All rights reserved.)