Evolutionary Ecology

The effect of predator behaviours on the evolution of colour pattern has been extensively studied in chemically defended prey but much less so in evasive prey, although similar selection regimes might be at play. Most previous work on the recognition and learning of colour patterns by predators has relied on experiments with few model predator species, preventing a proper assessment of how natural predator communities shape the evolution of prey signals. Here, we investigate predation on evasive iridescent blue Morpho helenor butterflies by wild avian communities in a tropical forest, using artificial butterflies exposed to natural bird assemblages attracted to insect-light traps in the field. We presented five prey types: evasive (local and exotic Morpho), cryptic, palatable-control and unpalatable-control. We recorded attacks from 43 different bird species, and compared attack latency, attack order and predation exerted by different birds on different prey types. Most birds avoided evasive and defended prey, but attack responses differed depending on their levels of specialization towards insect prey. Avoidance of conspicuous coloured prey was more prevalent in specialist flight-feeding, invertivorous birds, whereas more opportunistic treehunter and frugivorous guilds had weaker discrimination. Exotic and local evasive iridescent blue Morphos experienced similar predation rates, suggesting a generalization of iridescent blue signals associated with evasiveness by most birds. Finally, contrasting selection on ventral vs. dorsal patterns was detected in M. helenor, where cryptic ventral surfaces were exposed to attack by ground-foraging birds, whereas conspicuous iridescent blue coloration displayed during flight is associated with reduced attack rates. By revealing potential differences in the responses of specialist and generalist predators, this study highlights the importance of accounting for diversity of predator traits and behaviours when investigating the evolution of aposematism, mimicry, and other anti-predator adaptations.

Mullerian mimicry is the convergent evolution of warning signals among sympatric prey driven by predator learning. Theory therefore predicts signal homogeneity both within communities and within species that participate in Mullerian mimicry. Though rare, sexual dimorphism in Mullerian species does occur, but the underlying eco-evolutionary mechanisms are still relatively unexplored. Basing on the biology of aposematic butterflies, this study uses a modeling approach to test the hypothesis that sexual difference in defense can lead to the evolution of imperfect Mullerian mimicry in the less defended females as the consequence of opposing demands to minimize the cost of automimicry while maximizing reproductive output. Additionally, both the occurrence and degree of sexual dimorphism would decrease when the less defended sex becomes more valuable for reproduction, for example when offspring sex ratio is male biased or when females can mate only once in their lifetime. Findings from this study could help explain the evolution of extreme sexual dimorphism in some Mullerian systems, in which each sex mimics different models. Moreover, through understanding this intriguing exception to the rule, we will be able to gain a more complete picture of how a multitude of selective forces might shape the diversity in prey phenotypes.

In many tropical areas, seasonal rainfall leads to distinct dry and wet seasons. Many butterflies developing under wet season conditions develop into adults with large ventral eyespots on the wing margins, whereas those developing under dry season conditions have smaller or no eyespots. In greener, wet season habitats, larger eyespots can divert predator attacks toward the wing margins, while reduced eyespot size improves camouflage in the dry leaf litter-dominated habitat during the dry season. However, the dry season is also characterised by higher desiccation stress than the wet season. We hypothesised that larvae developing under dry season conditions develop into adults with higher desiccation tolerance than those reared under wet season conditions. We tested this by rearing larvae of the butterfly Mycalesis mineus under simulated dry and wet season conditions and assaying the desiccation tolerance of the resulting adults. Butterflies reared in dry conditions survived longer under desiccation stress, lost lesser water during pupal-adult metamorphosis, and were heavier than those reared in wet conditions. We also tested the correlation between eyespot size and desiccation tolerance. A negative correlation between the traits would be expected if similar developmental pathways regulate them. Consistent with this expectation, individuals with smaller eyespots had higher desiccation tolerance. Our results demonstrate plasticity in desiccation tolerance, and suggest that predator avoidance and desiccation tolerance traits may share similar developmental pathways.

Matching habitat choice provides a mechanism for individuals to maximise their expected fitness by selecting an environment that better fits their phenotype. Many animals choose their local environment by evaluating levels of perceived predation risk against possible resource gain. To test if predation risk is a major driver of habitat choice, we quantify scototaxis, or preference for dark versus light backgrounds, in juvenile guppies. As light backgrounds increase visibility to predators, this aspect of habitat choice captures variation in boldness in small fishes. By rearing and testing 586 fish descended from ten natural populations from Trinidad under common garden conditions, we first quantify (broad sense) heritable variation, i.e. evolutionary potential, within populations. Next, we test for evolutionary divergence among populations in mean preference, and if present, whether ancestral predation regime is a mediator of divergence. Finally, we ask whether families and/or populations differ in the amount of behavioural variation they contain. Habitat choice varied among families (12% of total variance), consistent with heritable variation (0.2). We also found mean preference varies among populations (11% of total variance explained). Evolutionary divergence among-populations is partly explained by ancestral predation regime, with populations from low-predation sites showing a stronger average preference for dark backgrounds than high-predation populations from the same river. Additionally, we find that within-population behavioural variation is greater in high-predation populations. We conclude that guppy populations contain heritable variation that could facilitate adaptive evolution if scototaxis is subject to natural selection. Furthermore, while genetic drift may also contribute to evolutionary divergence among-populations, observed patterns are qualitatively consistent with local adaption to predation regime. Our results suggests that high predation sites favour bolder habitat choice on average, but also that local predation regime shape the evolutionary dynamics of variation, perhaps by maintaining shy-bold variation among-individuals or by favouring individuals with less-predicable behaviour.

When encountering a predator, prey must choose between immobility and flight, a decision shaped by predator proximity, habitat structure, body size, and evolutionary history. Despite extensive work on optimal escape theory, few studies have jointly modelled both the decision to flee and the intensity of flight in a phylogenetic comparative framework. Here, we used a Bayesian phylogenetic hurdle log-normal model to analyze the probability of immobility and the conditional jump distance in 534 trials from 89 males across 17 Neotropical frog species (seven families), exposed to a simulated snake predator in three arenas of varying structural complexity. Physical contact with the predator (touch) was the strongest predictor, reducing immobility probability from 94% to 15% and increasing jump distance by 26%. Habitat complexity increased immobility (bush > leaf litter > empty), and frogs in open arenas jumped 31% farther. Larger-bodied species were substantially more likely to remain immobile but did not jump farther, indicating that body size determines strategy choice rather than locomotor magnitude. Phylogenetic signal was strong for both components (Pagels {lambda} = 0.80 for jump distance; {lambda} = 0.71 for immobility), with phylogeny accounting for 69-75% of variance. Species random effects formed a phylomorphospace in which fossorial species showed highest immobility and arboreal/torrent species favored active escape. Substantial individual-level variation in immobility tendency (25% of variance) provides a heritable substrate for ongoing selection. Frog antipredator strategies are jointly shaped by ecological context and evolutionary history; hurdle models offer a powerful framework for decomposing behavioral decisions. LAY SUMMARYWhen a predator approaches, prey must choose between staying still or fleeing -- a decision depending on body size, habitat, and shared evolutionary history. We exposed 17 frog species to a snake in arenas of varying vegetation cover. Frogs fled when touched but mostly stayed still when only approached; larger species and those in dense vegetation were most likely to remain immobile. These antipredator strategies were strongly shaped by frogs shared ancestry.

A similar phenotype exhibited by both adults and juveniles is often considered a self-evident default state due to shared genes and similar ecological niches, and thus the function of adult-juvenile resemblance is rarely addressed. An adaptive explanation for adult-juvenile resemblance is that adults mimic juveniles to attract mates by exploiting their parental care behavior and to avoid agonistic intrasexual combat from rivals that tolerate juveniles (i.e., the juvenile-mimicry hypothesis). Using a phylogenetic comparative approach, we tested the juvenile-mimicry hypothesis in aerial foragers, swallows and martins (Aves: Hirundinidae), in which adults and juveniles frequently encounter one another in their open habitat. We predicted that, if adults mimic juveniles, adult-juvenile resemblance should be enhanced in species with many young (i.e., a large number of models in relation to mimics) as well as species with a few young (i.e., a default state with limited intensity of sexual selection). This prediction was confirmed by a quadratic relationship between number of juveniles and adult-juvenile resemblance. In addition, as predicted under the juvenile-mimicry hypothesis, adult-juvenile resemblance was enhanced in species with multiple broods, in which juvenile-mimicry would be particularly effective due to the mating period followed by juvenile production. The observed pattern could not be explained by sexual selection for male ornamentation alone (i.e., with no juvenile-mimicry) even when considering the cost of ornamentation. An alternative explanation that juveniles mimic adults is also unlikely, as the situation favors the opposite pattern. The current study therefore supports the juvenile-mimicry hypothesis, indicating an adaptive function of adult-juvenile resemblance.

O_LITerrestrial insects are vulnerable to desiccation due to their small body size. Because insects lose most water through cuticular evaporation, cuticular traits strongly influence desiccation tolerance. Individuals with greater cuticular melanisation, i.e., darker ones, are hypothesised to tolerate desiccation better than less melanised ones. C_LIO_LIIn many butterflies, pupal colour is plastic - individuals pupating on leaves tend to be greener, while those that pupate away from leaves (off-leaf), such as on tree bark or defoliated twigs, tend to be browner. Brown pupae are hypothesised to have more cuticular melanin and are expected to experience higher desiccation stress than leaf-borne green pupae. Thus, plasticity in pupal melanisation may be an adaptation against desiccation. We tested this in the butterfly Eurema blanda. C_LIO_LIWe demonstrate that individuals pupating on on-leaf substrates are greener than those pupating on off-leaf substrates, and that desiccation stress is higher in the off-leaf substrates, a microenvironment typical of brown pupae, than in typical green pupae. Using Raman spectroscopy, we show that brown, but not green, pupal cuticles contain melanin. C_LIO_LIFollowing this, we obtained greener and browner pupae by manipulating substrate colour. When subjected to desiccation stress, browner pupae survived better than greener ones. There was no correlation between pupal colour and survival in the absence of desiccation stress. Thus, melanisation appears to confer a survival advantage to pupae by increasing desiccation tolerance. C_LIO_LISurvival under desiccating conditions was inversely related to water loss. Interestingly, melanisation did not correlate with water loss, suggesting that melanisation helps tolerate desiccation through physiological mechanisms not directly related to water loss reduction. C_LIO_LIOur findings reveal an additional, crucial, adaptive value of pupal colour plasticity, a trait that has been studied primarily from an anti-predatory perspective. C_LI

Understanding how anatomical structures evolve requires disentangling the roles of integration and modularity in shaping morphological variation. The vertebral column, a serially repeated and regionally differentiated structure, provides a powerful system for investigating these processes. Here, we examine how vertebral morphology evolves in relation to whole-body elongation across the adaptive radiation of Lake Malawi cichlid fishes. We tested for evolutionary integration between the precaudal and caudal domains, as well as assessed the contributions of vertebral count, centrum shape, and intervertebral spacing on body elongation. We find strong evolutionary integration between precaudal and caudal vertebral shape, with both vertebral shapes varying along shared axes of multivariate shape change. Despite this, precaudal and caudal vertebral counts evolve independently, indicating a decoupling between the evolution of identity and morphology. Whole-body elongation is significantly associated with coordinated changes in vertebral and rib morphology, including proportional increases in centrum size, posterior displacement of neural and haemal spines, and increased rib curvature. In contrast, centrum elongation and intervertebral spacing do not independently explain body elongation beyond vertebral counts. These results demonstrate that body elongation in cichlids necessitates integrated, multivariate changes in axial morphology. Our findings highlight the importance of morphological integration in facilitating coordinated evolutionary responses in anatomical systems.

Behaviour is a key yet often overlooked component of animal camouflage and how it evolves alongside colour and morphology remains poorly understood. The repeated evolution of stick-like postures in spiders offers a useful framework for investigating the importance of behaviour for concealment, since matching the environment should rely on specific body forms and postures, not just colouration. We hypothesised that when spiders behaviourally align their body with the background orientation it should influence the shape, posture and colouration that best enhances camouflage. To test this, we used a genetic algorithm and human observers to evolve digital spiders to be harder to find. We evaluated how selection under three behavioural orientation treatments (aligned, random, and evolvable orientation) influenced spider capture time, background match (lightness and colour), posture, and body (cephalothorax and abdomen) dimensions. We found that spiders that behaviourally aligned with the background took substantially longer to find through evolving a better background match, and a more elongated posture and body shape than randomly orientated spiders. Our spiders mirrored the shape and posture adopted by numerous clades, illustrating how behavioural camouflage represents a key concealment strategy in structurally complex habitats, part of an interacting suite of traits that encompass successful concealment.

Arctic and Boreal raptor communities will continue to be affected by borealization and other climate change related processes, providing a challenge for ecologists predicting future sates. However, by using community assembly theory and species traits, future communities may be predictable. In this study, we analyzed variation in reproduction traits as a consequence of diet specialization for 29 raptors, 2 skuas and 3 corvids. We assessed and implemented foraging traits for specialists and generalists into predator-prey models from which successful invasion conditions were derived. Specialist raptors produced larger clutch sizes, had a higher proportion of fledged per clutch and also expressed more variation compared to generalist raptors. These results suggest a relationship between diet specialization and reproductive traits which was also observed within phylogenetic orders. Specialist owls (Strigiformes) produced higher clutch sizes with a larger clutch range compared to generalist owls. The same pattern was observed for falcons (Falconiformes). No clear difference in reproduction was observed for specialist and generalist hawks, kites and eagles (Accipitriformes). Corvids expressed clutch sizes similar to that of specialist raptors while having the lowest proportion of fledged per clutch. Differences in foraging traits between specialists and generalists could be distinguished using functional response curves. A predator-prey model parameterized with foraging trait data showed that a generalist can coexist with a resident specialist if it has access to prey unavailable to the resident specialist. Otherwise, the native specialist outcompetes the invading generalist due to foraging efficiency. The combined empirical and theoretical findings in this study show how diet specialization affects both reproduction and the potential invasion success of raptors.

Altruism, in which individuals sacrifice some of their own reproduction to help others, can evolve if it is preferentially directed toward relatives. Organisms may recognize relatives through phenotypic similarity. Under the models originally studied by Hamilton, the threshold relatedness at which altruism becomes beneficial depends on the overall relatedness of the population. Implicit in this result is that natural selection may favor context-dependent strategies, in which donors judge their similarity to potential recipients relative to their similarity to the overall population when deciding whether to help. In this manuscript, we use a combination of simulations and theory to determine the circumstances under which context dependence is favored over simple strategies that do not depend on the observation of other interacting individuals. We find that a "plastic" strategy that uses the population context in its rule for donating consistently beats strategies that use only information about the potential recipient.

Electric organ discharge (EOD) waveform diversity in African elephantfish is often attributed to sexual selection, yet EODs also mediate active electrolocation during prey detection, raising the possibility that natural selection on foraging ecology contributes to waveform divergence. Paramormyrops kingsleyae exhibits an intraspecific polymorphism where certain populations emit biphasic EODs whereas other populations emit triphasic waveforms. The genes underlying this polymorphism show signatures of selection; the polymorphism persists despite gene flow and is behaviorally discriminable by the fish themselves. If waveform differences influence prey detection during active electrolocation, biphasic and triphasic fish should consume systematically different prey. We tested this prediction using DNA metabarcoding of gut contents from 186 mormyrids representing 16 species across eight sites in Gabon, employing two independent COI primer sets for cross-validation and pairing dietary data with environmental invertebrate sampling to distinguish active prey preference from passive availability. At the community level in the diverse Bale Creek mormyrid assemblage, species identity was the dominant predictor of diet composition (R{superscript 2} {approx} 24%), consistent with phylogenetic signal in foraging ecology. Within P. kingsleyae, waveform type was the strongest independent predictor of dietary composition (R{superscript 2} = 5-6%), explaining variance independently of geographic region, sex, body size, and parasitism status -- a result concordant across both primer sets. Dietary differences were driven by prey species turnover rather than differential abundance of shared prey, and prey selectivity analyses confirmed that waveform types differ in which prey they actively prefer, not merely in what is locally available. These findings are consistent with natural selection on foraging ecology contributing to the maintenance of EOD waveform polymorphism, though the sensory mechanisms linking subtle waveform differences to prey detection remain an open question.

Color polymorphism can facilitate local adaptation, maintain intraspecific diversity, or reflect early stages of speciation. Clownfishes (Amphiprion spp.) typically display a simple black, orange, and white pattern, but the saddleback clownfish (Amphiprion polymnus) shows striking variation in melanism and the number of vertical bars, which are thought to play a role in species recognition. In 2024, a revision on iNaturalist split A. polymnus into multiple species based solely on color pattern and geographic range. This raises the question of whether these morphs represent true species or intraspecific polymorphism, which we tested using genomic and image-based data. We sampled 97 individuals from seven populations across the species range and quantified color patterns from standardized photographs. Phenotypic and genomic analyses reveal a complex pattern of divergence. Image analysis identified three distinct phenotypic clusters, with A. polymnus, A. annamensis, and A. laticlavius each showing consistent differences in saddle shape and vertical bar extent. ADMIXTURE resolved three distinct genetic groups corresponding to the morphs. Pairwise FST (0.54-0.71) and dxy indicate extremely high differentiation between A. polymnus and A. annamensis, consistent with species-level divergence, whereas A. laticlavius shows much lower differentiation from A. polymnus (FST 0.09-0.18) and higher differentiation from A. annamensis (FST 0.64-0.66). Overall, phenotypic and genomic data show structured variation, but the status of A. laticlavius remains ambiguous. Our study reveals clear and structured divergence across the full range, yet the taxonomic interpretation of this variation remains inherently challenging. The key question remains: do these patterns reflect a single polymorphic species or a complex of closely related species?

Interactions between cleaner fish Labroides dimidiatus and client fish, from which cleaners remove ectoparasites and mucus, represent a textbook example of mutualism involving sophisticated strategic decision-making. However, cleaners must also face intraspecific social challenges within a size-based hierarchy, where the largest females may eventually change sex and become males with higher reproductive rates. Following 540 individuals over 11 months, we found that, contrary to expectations, slow-growing females spent more time cleaning and cheated more frequently, without causing more negative client responses than fast-growing females did. Instead, variation in growth was best explained by social factors: fast-growing individuals experienced reduced social control, while slow growers spent more time in proximity to dominant individuals. As there was no evidence that spawning activity affected growth patterns, it appears that fast growth as a viable strategy for becoming a male largely depends on the lack of control by dominants.

The general random walk model (GRW) of Hunt (2006) is used to infer directional evolution in mean trait values from sparse fossil data by modeling phenotypic change as the accumulated result of small steps with mean step sizes and step variances. Using simulations and real data cases, Ergon (2026) showed that the step variances can be estimated reasonably well only when the mean trait values have small measurement errors, while for fossil data with realistic measurement errors they appear to be extremely difficult to find, and they are often found to be negative. In the simulations Ergon (2026) assumed that the true phenotypic mean values were known. Here, I essentially repeat these simulations under the assumption that only mean trait values with large measurement errors are known, and based on weighted mean squared error (WMSE) comparisons the conclusion is that weighted least squares (WLS) is a better method than GRW. A second conclusion is that WLS is a better method also in the possibly rare cases with large measurement errors where the GRW parameters are estimated well. The GRW method is simply not flexible enough to handle such cases. A third conclusion is that Akaike Information Criterion (AIC) results for GRW models with large measurement errors relative to the step variance may be overly optimistic.

The impacts of a changing abiotic environment on fitness and performance arise not only from low tolerance to new environmental conditions, but also from changes in the abundance and interaction intensity with other species. The strength of the interaction may itself depend on how well each species performs across environments, but there is a dearth of studies investigating how intrinsic fitness and interaction intensity covary across an abiotic environmental gradient. We addressed this question in a hypersaline consumer-resource system: the microalga Dunaliella spp. grazed by the brine shrimp Artemia franciscana. We exposed four Dunaliella strains to a range of salinities above seawater, with or without brine shrimps, and tracked their population sizes over time and the survival of their predators, to estimate basic parameters of a Lotka-Volterra model. We found that the intrinsic growth rate of algae, the survival rate of predators, and the per-capita predation rate, all varied with salinity and algal strain. Significant interactions between strain and salinity further revealed that these ecological responses to salinity are evolvable. Together with correlations between demographic parameters across salinity, this suggests that predation may influence the evolution of salinity tolerance curves, blurring the line between the fundamental and realized niches.

True crabs (Brachyura) are among the most iconic marine arthropods, representing noteworthy examples of morphological and ecological disparity. A striking feature of brachyurans are their anterior pincer-like appendages: chelipeds. These structures showcase a large diversity of morphologies that reflect ecology and overall multifunctionality. Yet, a comprehensive assessment of appendage functional morphology within phylogenetic and ecological trait contexts has never been attempted. By combining 3D geometric morphometrics, finite element analyses, multilocus molecular phylogeny, and ecological trait data for 80 crab species, including three fossil forms, we unveil a complex evolutionary history for crab chelipeds. Despite extreme shape diversity amongst chelipeds, stress distributions are very similar across taxa and hint a many-to-one pattern. High concentrations of chelipeds within constrained morphospace regions associated with peak pinch forces illustrates that brachyuran morphologies optimised for shell crushing may have arisen in the Cretaceous. Deviations from this morphospace highlight the diversification of non-shell-crushing life modes and the influence of sexual selection on appendages. Neither cheliped shape nor pinch force show phylogenetic signal. Together these results indicate that the evolution of cheliped shape is closely associated with, and inferred to have been strongly influenced by, crab ecology, biomechanical needs and sexual selection. SIGNIFICANCE STATEMENTChelipeds, the pincer-like claws of crabs, are among the most morphologically diverse appendages within Arthropoda, yet the evolutionary forces driving this diversity remain poorly understood. By integrating 3D geometric morphometrics, biomechanical modelling, molecular phylogeny, and ecological data across 80 crab species including fossil forms, we demonstrate that cheliped morphology is driven by ecology, biomechanical demands, and sexual selection rather than phylogenetic relatedness. The multifunctionality of these structures produces strong evidence for many-to-one mapping of form to function. Morphologies optimised for durophagy appear to have originated in the Cretaceous, with subsequent diversification into manipulative and sexually selected forms from a morphologically flexible foundation. These findings demonstrate that cheliped diversity reflects a complex interplay between ecological specialisation, biomechanical optimisation, and sexual selection across Brachyura.

AO_SCPLOWBSTRACTC_SCPLOWEnvironmental heterogeneity across freshwater systems often promotes phenotypic variation, yet disentangling environmentally induced variation from heritable differentiation remains a central goal in evolutionary ecology. We investigated the geographic distribution and morphological differentiation, and heritability of shell traits among populations of the freshwater lymnaeid snail Pectinidens diaphanus in Patagonia. Extensive field surveys across 196 freshwater sites revealed that the species occupies a broad range of lentic and lotic habitats and constitutes the only lymnaeid inhabiting southern Patagonia. While reproductive anatomical structures were conserved across populations, shell shape differed markedly among populations from contrasting habitat types, with population identity explaining nearly 50% of total shape variation. Populations from hydrologically unstable habitats (ponds and streams) exhibited more elongated shells and relatively smaller apertures, a pattern consistent with functional responses to hydroperiod variability and desiccation risk. To assess the heritability of this differentiation, we conducted a common-garden experiment across two generations. Shell shape differences between permanent- (lagoon) and temporary- (pond) habitat-derived populations persisted into the G2 generation reared under standardized laboratory conditions, indicating that the observed variation is not solely a response to local environmental conditions but includes a heritable component. Together, our findings demonstrate that P. diaphanus constitutes the sole lymnaeid across southern Patagonia, occupying a broader range than previously documented, and that populations show heritable shell differentiation potentially associated with contrasting freshwater habitats. By integrating large-scale biogeographic surveys with morphometric and experimental approaches, this study provides new insight into how habitat variation may contribute to ecological and evolutionary differentiation in freshwater gastropods.

Many animals have camouflage appearances that correspond to the habitat where they live, termed phenotype-environment matching. However, this has generally been tested in only a limited number of systems and natural settings, and often not to the relevant vision of key receivers (predators) across different spatial scales. Here, we measured the plumage attributes and putative camouflage used by ground-nesting bird species specialist to particular biomes, specifically tropical rainforest, taiga forest, dry forest, grassland, desert, and tundra from museum specimens. Digital photography and image analysis were used to quantify colour patterns to models of predator vision to understand how different colour patterns may correspond with biome type. With this information, we next created bird models that were photographed in situ in the Valdivian temperate rainforest and Patagonian grassland biomes of Chile to quantify the extent to which plumage coloration and pattern traits provide effective camouflage at different spatial scales. In general, we find that specialist ground-nesting birds express a phenotype that better matches the substrate composition and vegetation structure across large spatial scales of their own biome. This study reveals how animal camouflage works across biomes, relative to the visual system of raptor predators, and at the appropriate distance at which detection may occur.

Reproductive biology is a key determinant of fitness. State-dependent speciation-extinction methods (SSEs) are often used to associate traits with patterns of diversification. Previously, SSEs have been used within families to investigate the hypothesis that selfing is an evolutionary "dead end." To the best of the authors knowledge, no study has looked across families, which would increase power to more generally test this hypothesis. Here, we examine the impact of 1) mating system and 2) sexual system on diversification across 18 phylogenetically diverse families. We also discuss how more recent advances in SSE models (i.e., "hidden state" and tree-only models) influence our interpretation of these patterns and evaluate how the relationship between mating and sexual systems can be leveraged to gain insight into the impact of reproductive biology on evolutionary outcomes. In this study, we find that the mating system as a trait does not better explain patterns of diversification when compared to null models, but the sexual system often does. We also find family-level heterogeneity in our results, which suggests conclusions drawn from studies on individual families may not be consistent with any broader trend.