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Crater lake fishes are common evolutionary model systems, with recent studies suggesting a key role for gene flow in promoting rapid adaptation and speciation. However, the study of these young lakes can be complicated by human-mediated extinctions. Museum genomics approaches integrating genetic data from recently extinct species are, therefore, critical to understanding the complex evolutionary histories of these fragile systems. Here, we examine the evolutionary history of an extinct Southern Hemisphere crater lake endemic, the rainbowfish Melanotaenia eachamensis. We undertook a comprehensive sampling of extant rainbowfish populations of the Atherton Tablelands of Australia alongside historical museum material to understand the evolutionary origins of the extinct crater lake population and the dynamics of gene flow across the ecoregion. The extinct crater lake species is genetically distinct from all other nearby populations due to historic introgression between 2 proximate riverine lineages, similar to other prominent crater lake speciation systems, but this historic gene flow has not been sufficient to induce a species flock. Our results suggest that museum genomics approaches can be successfully combined with extant sampling to unravel complex speciation dynamics involving recently extinct species. [ABSTRACT FROM AUTHOR]

The translocation of species outside their natural range is a threat to aquatic biodiversity globally, especially freshwater fishes, as most are not only susceptible to predation and competition but readily hybridize with congeners.Running River rainbowfish (RRR, Melanotaenia sp.) is a narrow‐ranged, small‐bodied freshwater fish that recently became threatened and was subsequently listed as Critically Endangered, owing to introgressive hybridization and competition following the translocation of a congeneric species, the eastern rainbowfish (Melanotaenia splendida).To conserve RRR, wild fish were taken into captivity, genetically confirmed as pure representatives, and successfully bred. As the threat of introgression with translocated eastern rainbowfish could not be mitigated, a plan was devised to translocate captive raised RRR into unoccupied habitats within their native catchment, upstream of natural barriers. The translocation plan involved careful site selection and habitat assessment, predator training (exposure to predators prior to release), soft release (with a gradual transition from captivity to nature), and post‐release monitoring, and this approach was ultimately successful.Two populations of RRR were established in two previously unoccupied streams above waterfalls with a combined stream length of 18 km. Post‐release monitoring was affected by floods and low sample sizes, but suggested that predation and time of release are important factors to consider in similar conservation recovery programmes for small‐bodied, short‐lived fishes. [ABSTRACT FROM AUTHOR]

Despite belonging to the most abundant and widespread genus of freshwater fishes in the region, the carp gudgeons of eastern Australia (genus Hypseleotris) have proved taxonomically and ecologically problematic to science since the 19th century. Several molecular studies and a recent taxonomic revision have now shed light on the complex biology and evolutionary history that underlies this group. These studies have demonstrated that carp gudgeons include a sexual/unisexual complex (five sexual species plus an assortment of hemiclonal lineages), many members of which also co‐occur with an independent sexual relative, the western carp gudgeon (H. klunzingeri). Here, we fill yet another knowledge gap for this important group by presenting a detailed molecular phylogeographic assessment of the western carp gudgeon across its entire and extensive geographic range. We use a suite of nuclear genetic markers (SNPs and allozymes) plus a matrilineal genealogy (cytb) to demonstrate that H. klunzingeri s.l. also displays considerable taxonomic and phylogeographic complexity. All molecular datasets concur in recognizing the presence of multiple candidate species, two instances of historic between‐species admixture, and the existence of a natural hybrid zone between two of the three candidate species found in the Murray–Darling Basin. We also discuss the major phylogeographic patterns evident within each taxon. Together, these analyses provide a robust molecular, taxonomic, and distributional framework to underpin future morphological and ecological investigations on this prominent member of regional freshwater ecosystems in eastern Australia. [ABSTRACT FROM AUTHOR]

Context: Galaxiids are a widespread, southern hemisphere, radiation of mostly obligate freshwater fishes. Tasmania houses a diversity of endemic species of Galaxias and Paragalaxias. Of these, many are at risk of extinction, being landlocked, range-restricted and subject to anthropogenic threats, placing a high-conservation priority on the region. Aim: Our aim was to synthesise historic and published molecular datasets to provide the sound systematic framework needed to underpin future conservation and taxonomic efforts for Tasmanian galaxiids. Methods: Novel and published nuclear (allozyme) and matrilineal (cytb) datasets were generated and integrated for every putative Tasmanian galaxiid species lacking a comparable multi-gene assessment. Key results: The Tasmanian galaxiids are phylogenetically diverse, with molecular data generally supporting the accepted taxonomy, but with potential species-level diversity noted within an alpine radiation of the Galaxias truttaceus complex and further support for synonymy of G. niger within G. brevipinnis. Conclusions: This study highlights the value of multi-locus studies in both validating species-level taxonomy and resolving taxonomic ambiguities and conservation priorities within Tasmania's galaxiids. Implications: Our integrated genetic analyses provide a framework to underpin more in-depth genomic approaches to assess additional cryptic diversity and conservation planning, such as genetic rescue and ex situ population security. Tasmania represents less than 1% of Australia's landmass, yet houses a quarter of Australia's threatened freshwater fishes, all of them being galaxiids. However, comprehensive genetic assessments of the taxonomic integrity of Tasmania's galaxiid fishes are available only for 2 of its 17 described species. This study had plugged this gap for the remaining 15 species. Although confirming most species as valid, it identified instances of taxonomic uncertainty and highlighted priority areas for future conservation genomic investigation. [ABSTRACT FROM AUTHOR]

Aim: Major knowledge gaps exist regarding the evolution of arid zone organisms. For freshwater species with high dispersal potential, little is known if historical aridification influenced connectivity across drainage divides and impacted on their divergence and diversification. We tested the hypothesis that the historical aridification of Australia promoted the isolation and influenced the demographic histories and evolutionary divergence of a migratory group of freshwater obligates. Location: Central and eastern Australia; Murray–Darling Basin (MDB), Lake Eyre Basin (LEB), Fitzroy Basin (FIT). Taxon Three lineages of golden perch (Macquaria ambigua), a widespread fishery resource from inland Australia. Methods: We obtained genome‐wide data for golden perch sampled throughout their range. Phylogenetic relationships were reconstructed using maximum likelihood. Species distribution modelling was used to predict contemporary and past distributions for the three lineages and to develop hypotheses regarding their biogeographic and demographic histories. Hypotheses were independently tested using coalescent simulations in fastsimcoal and DIYABC with the genomic dataset. Results: We found evidence for three reciprocally monophyletic lineages that have experienced little to nil genetic connectivity since divergence. Coalescent models suggest that the coastal (FIT) and inland (MDB and LEB) lineages diverged ~103 thousand years ago (ka), followed by the split of MDB and LEB lineages ~58 ka. These timings agree with reductions of large freshwater environments in Australia during the late Pleistocene. Species distribution models show an extreme decrease in habitat during the Last Glacial Maximum ~21 ka, consistent with inferred demographic contractions in coalescent tests. Main conclusions We reveal that aridification of Australia during the late Pleistocene has driven and reinforced the divergence of a migratory freshwater obligate. Our findings are important for informing the conservation management of aquatic organisms under climate change. This work further demonstrates the value of using species distribution modelling to formulate diversification hypotheses and to improve interpretation of coalescent analyses. [ABSTRACT FROM AUTHOR]

A recent study argued that coalescent-based models of species delimitation mostly delineate population structure, not species, and called for the validation of candidate species using biological information additional to the genetic information, such as phenotypic or ecological data. Here, we introduce a framework to interrogate genomic datasets and coalescent-based species trees for the presence of candidate species in situations where additional biological data are unavailable, unobtainable or uninformative. For de novo genomic studies of species boundaries, we propose six steps: (1) visualize genetic affinities among individuals to identify both discrete and admixed genetic groups from first principles and to hold aside individuals involved in contemporary admixture for independent consideration; (2) apply phylogenetic techniques to identify lineages; (3) assess diagnosability of those lineages as potential candidate species; (4) interpret the diagnosable lineages in a geographical context (sympatry, parapatry, allopatry); (5) assess significance of difference or trends in the context of sampling intensity; and (6) adopt a holistic approach to available evidence to inform decisions on species status in the difficult cases of allopatry. We adopt this approach to distinguish candidate species from within-species lineages for a widespread species complex of Australian freshwater fishes (Retropinna spp.). Our framework addresses two cornerstone issues in systematics that are often not discussed explicitly in genomic species discovery: diagnosability and how to determine it, and what criteria should be used to decide whether diagnosable lineages are conspecific or represent different species. [ABSTRACT FROM AUTHOR]

How populations of aquatic fauna persist in extreme desert environments is an enigma. Individuals often breed and disperse during favorable conditions. Theory predicts that adaptive capacity should be low in small populations, such as in desert fishes. We integrated satellite‐derived surface water data and population genomic diversity from 20,294 single‐nucleotide polymorphisms across 344 individuals to understand metapopulation persistence of the desert rainbowfish (Melanotaenia splendida tatei) in central Australia. Desert rainbowfish showed very small effective population sizes, especially at peripheral populations, and low connectivity between river catchments. Yet, there was no evidence of population‐level inbreeding and a signal of possible adaptive divergence associated with aridity was detected. Candidate genes for local adaptation included functions related to environmental cues and stressful conditions. Eco‐evolutionary modeling showed that positive selection in refugial subpopulations combined with connectivity during flood periods can enable retention of adaptive diversity. Our study suggests that adaptive variation can be maintained in small populations and integrate with neutral metapopulation processes to allow persistence in the desert. [ABSTRACT FROM AUTHOR]

Adaptive radiations are generally thought to occur soon after a lineage invades a region offering high levels of ecological opportunity. However, few adaptive radiations beyond a handful of exceptional examples are known, so a comprehensive understanding of their dynamics is still lacking. Here, we present a novel case of an island species flock of freshwater fishes with a radically different tempo of adaptive history than that found in many popular evolutionary model systems. Using a phylogenomic data set combined with simultaneous Bayesian estimation of divergence times and trait-based speciation and extinction models, we show that the New Zealand Gobiomorphus gudgeons comprise a monophyletic assemblage, but surprisingly, the radiation did not fully occupy freshwater habitats and explosively speciate until more than 10 myr after the lineage invaded the islands. This shift in speciation rate was not accompanied by an acceleration in the rate of morphological evolution in the freshwater crown clade relative to the other species, but is correlated with a reduction in head pores and scales as well as an increase in egg size. Our results challenge the notion that clades always rapidly exploit ecological opportunities in the absence of competing lineages. Instead, we demonstrate that adaptive radiation can experience a slow start before undergoing accelerated diversification and that lineage and phenotypic diversification may be uncoupled in young radiations. [Adaptive radiation; Eleotridae; freshwater; Gobiomorphus ; New Zealand.] [ABSTRACT FROM AUTHOR]

While the influence of Pleistocene climatic changes on divergence and speciation has been well‐documented across the globe, complex spatial interactions between hydrology and eustatics over longer timeframes may also determine species evolutionary trajectories. Within the Australian continent, glacial cycles were not associated with changes in ice cover and instead largely resulted in fluctuations from moist to arid conditions across the landscape. We investigated the role of hydrological and coastal topographic changes brought about by Plio‐Pleistocene climatic changes on the biogeographic history of a small Australian freshwater fish, the southern pygmy perch Nannoperca australis. Using 7958 ddRAD‐seq (double digest restriction‐site associated DNA) loci and 45,104 filtered SNPs, we combined phylogenetic, coalescent and species distribution analyses to assess the various roles of aridification, sea level and tectonics and associated biogeographic changes across southeast Australia. Sea‐level changes since the Pliocene and reduction or disappearance of large waterbodies throughout the Pleistocene were determining factors in strong divergence across the clade, including the initial formation and maintenance of a cryptic species, N. 'flindersi'. Isolated climatic refugia and fragmentation due to lack of connected waterways maintained the identity and divergence of inter‐ and intraspecific lineages. Our historical findings suggest that predicted increases in aridification and sea level due to anthropogenic climate change might result in markedly different demographic impacts, both spatially and across different landscape types. [ABSTRACT FROM AUTHOR]

Flathead gobies (genus Glossogobius) include c. 40 small‐ to medium‐sized benthic fishes found primarily in freshwater habitats across the Indo‐Pacific, having biodiversity value as well as cultural and economic value as food fishes, especially in developing countries. To help resolve considerable confusion regarding the identification of some of the larger‐growing Glossogobius species, a systematic framework was established using nuclear genetic markers, mitochondrial DNA barcoding and phenotypic evidence for a geographically widespread collection of individuals from the waterways of tropical northern Australia. Species boundaries and distribution patterns were discordant with those previously reported, most notably for the tank goby Glossogobius giuris, which included a cryptic species. Genetic divergence was matched with accompanying unique visual characters that aid field identification. Additional taxonomic complexity was also evident, by comparison with DNA barcodes from international locations, suggesting that the specific names applicable for two of the candidate species in Australia remain unresolved due to confusion surrounding type specimens. Although flathead gobies are assumed to be widespread and common, this study demonstrates that unrealised taxonomic and ecological complexity is evident, and this will influence assessments of tropical biodiversity and species conservation. This study supports the need for taxonomic studies of freshwater fishes to underpin management in areas subject to significant environmental change. [ABSTRACT FROM AUTHOR]

Metazoans usually reproduce sexually, blending the unique identity of parental genomes for the next generation through functional crossing-over and recombination in meiosis. However, some metazoan lineages have evolved reproductive systems where offspring are either full (clonal) or partial (hemiclonal) genetic replicas. In the latter group, the process of uniparental genome elimination selectively eliminates either the maternal or paternal genome from germ cells, and only one parental genome is selected for transmission. Although fairly common in plants, hybridogenesis (i.e. clonal haploidization via chromosome elimination) remains a poorly understood process in animals. Here, we explore the proximal cytogenomic mechanisms of somatic and germ cell chromosomes in sexual and hybrid genotypes of Australian carp gudgeons (Hypseleotris) by tracing the fate of each set during mitosis (in somatic tissues) and meiosis (in gonads). Our comparative study of diploid hybrid and sexual individuals revealed visually functional gonads in male and female hybrid genotypes and generally high karyotype variability, although the number of chromosome arms remains constant. Our results delivered direct evidence for classic hybridogenesis as a reproductive mode in carp gudgeons. Two parental sets with integral structure in the hybrid soma (the F1 constitution) contrasted with uniparental chromosomal inheritance detected in gonads. The inheritance mode happens through premeiotic genome duplication of the parental genome to be transmitted, whereas the second parental genome is likely gradually eliminated already in juvenile individuals. The role of metacentric chromosomes in hybrid evolution is also discussed. [ABSTRACT FROM AUTHOR]

Abstract Background Understanding how freshwater assemblages have been formed and maintained is a fundamental goal in evolutionary and ecological disciplines. Here we use a historical approach to test the hypothesis of codivergence in three clades of the Chilean freshwater species assemblage. Molecular studies of freshwater crabs (Aegla: Aeglidae: Anomura) and catfish (Trichomycterus arealatus: Trichomycteridae: Teleostei) exhibited similar levels of genetic divergences of mitochondrial lineages between species of crabs and phylogroups of the catfish, suggesting a shared evolutionary history among the three clades in this species assemblage. Results A phylogeny was constructed for Trichomycterus areolatus under the following best-fit molecular models of evolution GTR + I + R, HKY + I, and HKY for cytochrome b, growth hormone, and rag 1 respectively. A GTR + I + R model provided the best fit for both 28S and mitochondrial loci and was used to construct both Aegla phylogenies. Three different diversification models were observed and the three groups arose during different time periods, from 2.25 to 5.05 million years ago (Ma). Cladogenesis within Trichomycterus areolatus was initiated roughly 2.25 Ma (Late Pliocene - Early Pleistocene) some 1.7 - 2.8 million years after the basal divergences observed in both Aegla clades. These results reject the hypothesis of codivergence. Conclusions The similar genetic distances between terminal sister-lineages observed in these select taxa from the freshwater Chilean species assemblage were formed by different processes occurring over the last ~5.0 Ma. Dramatic changes in historic sea levels documented in the region appear to have independently shaped the evolutionary history of each group. Our study illustrates the important role that history plays in shaping a species assemblage and argues against assuming similar patterns equal a shared evolutionary history.

The ecological impacts of increasing global temperatures are evident in most ecosystems on Earth, but our understanding of how climatic variation influences natural selection and adaptive resilience across latitudes remains largely unknown. Latitudinal gradients allow testing general ecosystem‐level theories relevant to climatic adaptation. We assessed differences in adaptive diversity of populations along a latitudinal region spanning highly variable temperate to subtropical climates. We generated and integrated information from environmental mapping, phenotypic variation and genome‐wide data from across the geographical range of the rainbowfish Melanotaenia duboulayi, an emerging aquatic system for studies of climate change. We detected, after controlling for spatial population structure, strong interactions between genotypes and environment associated with variation in stream flow and temperature. Some of these hydroclimate‐associated genes were found to interact within functional protein networks that contain genes of adaptive significance for projected future climates in rainbowfish. Hydroclimatic selection was also associated with variation in phenotypic traits, including traits known to affect fitness of rainbowfish exposed to different flow environments. Consistent with predictions from the "climatic variability hypothesis," populations exposed to extremes of important environmental variables showed stronger adaptive divergence and less variation in climate‐associated genes compared to populations at the centre of the environmental gradient. Our findings suggest that populations that evolved at environmental range margins and at geographical range edges may be more vulnerable to changing climates, a finding with implications for predicting adaptive resilience and managing biodiversity under climate change. [ABSTRACT FROM AUTHOR]

1.Freshwater ecosystems worldwide harbour disproportionately high numbers of endemic species under threat from human activity, particularly accelerated habitat fragmentation. The Murray–Darling Basin in south‐eastern Australia, one of the country's largest and arguably its most vulnerable freshwater ecosystem, is inhabited by a number of small‐bodied fishes that are threatened with imminent extinction.2.Here an extensive microsatellite dataset was used, supplemented by additional allozyme and mitochondrial DNA analyses, to assess the genetic diversity, population structure and contemporary migration patterns in the Murray hardyhead Craterocephalus fluviatilis, one of Australia's most threatened fishes.3.Genetic diversity estimates, primarily based on 413 fish collected during the latter period of intense drought (1997–2010) from 23 sites and genotyped at 14 microsatellite loci, were higher than those previously detected for other regionally co‐occurring small‐bodied freshwater fishes.4.Population structure analyses identified a subtle primary split between 'lower Murray' (lower river reaches) versus 'upstream Murray' (upper river reaches) and a total of nine genetically similar sub‐populations. This includes unexpected sub‐population differentiation in the Lower Lakes, a region at the terminus of the Murray–Darling Basin that most often has inter‐connected habitat.5.Very low levels of contemporary migration were detected between most inferred populations (<2%) during the drought, with all exceptions involving moderate levels of migration from an upstream sub‐population into an adjacent downstream sub‐population.6.This article describes how these genetic data have guided translocation and reintroduction efforts in recent years. We advocate the use of assisted gene flow as a central component of continuing efforts to rescue this species from imminent extinction. [ABSTRACT FROM AUTHOR]

Globally, freshwater fishes are declining at an alarming rate. Despite much evidence of catastrophic declines, few Australian species are listed as threatened under national legislation. We aim to help redress this by identifying the Australian freshwater fishes that are in the most immediate risk of extinction. For 22 freshwater fishes (identified as highly threatened by experts), we used structured expert elicitation to estimate the probability of extinction in the next ~20 years, and to identify key threats and priority management needs. All but one of the 22 species are small (<150 mm total length), 12 have been formally described only in the last decade, with seven awaiting description. Over 90% of these species were assessed to have a >50% probability of extinction in the next ~20 years. Collectively, the biggest factor contributing to the likelihood of extinction of the freshwater fishes considered is that they occur in small (distributions ≤44 km2), geographically isolated populations, and are threatened by a mix of processes (particularly alien fishes and climate change). Nineteen of these species are unlisted on national legislation, so legislative drivers for recovery actions are largely absent. Research has provided strong direction on how to manage ~35% of known threats to the species considered, and, of these, ~36% of threats have some management underway (although virtually none are at the stage where intervention is no longer required). Increased resourcing, management intervention and social attitudinal change is urgently needed to avert the impending extinction of Australia's most imperilled freshwater fishes. Australian freshwater fishes have typically been neglected in conservation planning, despite evidence of catastrophic declines. Here we use structured expert elicitation to identify the Australian freshwater fishes in imminent risk of extinction. All 22 species considered had moderate to high (>40%) likelihoods of extinction in the next two decades. Using conservation progress metrics, we identify priority management needs for averting future extinctions. [ABSTRACT FROM AUTHOR]

Aim: Despite the influence of sea‐level changes on biogeographic/phylogeographic patterns in freshwater ecosystems being well documented, studies that explicitly link the influence of sea‐level change with speciation are rare. We aim to test the hypothesis that sea‐level changes during the Pliocene and Pleistocene have driven speciation in north‐western Australia's (NWA's) largest freshwater fish family, Terapontidae, building upon a body of evolutionary literature focussed on the family. Location: North‐western Australian rivers including those draining the Kimberley Plateau. Taxon: Grunters (Family: Terapontidae, Genera: Hannia, Hephaestus, Leiopotherapon, Syncomistes). Methods: A GIS was used to reconstruct palaeodrainages during lowered sea levels and to delineate regions of high connectivity during low and high (current) sea‐level conditions. For seven species, the degree of phylogenetic divergence among river basins in different regions was evaluated using a maximum likelihood phylogeny and analyses of the proportion of genetic divergence expressed with 601 base pairs of the mtDNA cytochrome b (cytb) gene. Results: A low proportion of cytb haplotypes were shared among catchments not connected by the same receiving waters (e.g. estuaries) under current (high) sea levels, indicating that contemporary dispersal is limited over fine spatial scales. Deeper phylogeographic patterns were largely congruent with reconstructed low sea‐level (LSL) drainage arrangements indicating that historic among‐catchment connectivity was far more widespread under LSL conditions. Main Conclusions: The NWA landscape represents a geographic template that has shaped patterns of broad dispersal under low sea levels, and fine‐scale isolation under high sea levels. The weight of evidence from recent literature on species boundaries and evolutionary patterns within the terapontids suggests that most NWA species were derived rapidly and recently from a series of spatio‐temporal vicariant events caused by such sea‐level fluctuations during the late Pliocene and Pleistocene. Together, the findings provide a rare, comprehensively tested example of sea‐level change driving speciation in the tropics. [ABSTRACT FROM AUTHOR]

New Zealand has a complex recent history of climatic and tectonic change that has left variable signatures in the geographic distribution and genetic structure of the region's flora and fauna. To identify concordant patterns, a broad range of taxa must be examined and compared. In New Zealand's North Island, a consensus is forming as to the dominant biogeographic barriers in the region although obligate freshwater taxa have not been considered in this framework. We use single-nucleotide polymorphisms to investigate phylogeography in the widespread obligate freshwater fish Gobiomorphus basalis on the North Island. Phylogeographic patterns within G. basalis reveal biogeographic disjunctions that are in some ways consistent and in other ways at odds with established patterns, providing insight into the processes that have shaped the islands' biogeography. We also use phylogeography to delineate species boundaries within the entire New Zealand radiation of Gobiomorphus and find that it contains several morphologically cryptic species. We resolve two clades within G. basalis that correspond to areas north and south of the Taupo Volcanic Zone. We confirm the distinctiveness of Gobiomorphus alpinus relative to Gobiomorphus cotidianus , as well as the presence of two lineages within Gobiomorphus breviceps that were previously identified based on mitochondrial data. [ABSTRACT FROM AUTHOR]

Conservation translocations are becoming more common to assist in the management of threatened native species. While many translocation programs focus on maximizing survival in newly established populations, consideration is also required for the persistence of source populations.Here, we present and test a theoretical framework that assesses the translocation trade‐off between increasing a species probability of survival and decreasing a species' overall genetic diversity. We anticipate that (a) the genetic diversity of translocated populations will be reduced compared to the source due to a failure to capture and retain genetic diversity and (b) the genetic diversity of the source population will decline due to the removal of founder individuals.We test this framework with an empirical study of redfin blue eye Scaturiginichthys vermeilipinnis, a critically endangered fish species which has undergone several replicate translocations, established with founders sourced from a single remnant population. Several generations after reintroduction, we show that the predicted survival of the species has improved as a result of these translocations.While the species' genetic diversity has been retained across all populations combined (translocated and source), we show that genetic diversity in each individual population (including the source) is reduced compared to the source population prior to translocation.Synthesis and applications. Conservation translocations can provide great benefits to species survival, enabling extinction risk to be spread across multiple populations. Translocated populations, however, often harbour reduced genetic diversity compared to source populations and initiating translocated populations can decrease the genetic diversity of source populations, placing them at an increased risk of extinction. The framework presented here enables the trade‐off between extinction risk and retention of genetic diversity to be established. This will enable the optimal conservation strategy to be employed to increase the long‐term persistence and evolutionary potential of a species. [ABSTRACT FROM AUTHOR]