Selection Hypothesis Research Articles

The Role of Word Form in Lexical Selection of Late Talkers.

The lexical selection hypothesis posits that first words added to a toddler's spoken vocabulary will be predominantly those beginning with early developing consonant phonemes. Using this framework, we evaluated the relationship between word form and lexical selection among late talkers and two typical comparison groups. An online database of MacArthur-Bates Communicative Developmental Inventories was used to extract the American English Words and Sentences Form (MB-CDI:WS). Inventories were divided into three groups: (a) a late talkers group (LTs; n = 202), (b) a typically developing age-matched group (TDA; n = 1,238), and (c) a younger, typically developing language-matched group (TDL; n = 196) matched on expressive language to the LTs. The first phoneme in each word produced by every toddler on the MB-CDI:WS was coded as early, middle, or late developing. The proportion of spoken words starting with phonemes in each developmental category was calculated. Mixed-effects models were used to evaluate group differences. All three groups' spoken vocabularies consisted mostly of words beginning with early developing phonemes. LTs and TDLs used more words beginning with early developing consonants than TDAs. TDAs had a higher proportion of words starting with middle- and late- developing phonemes than LTs and TDL groups. The LTs group produced a significantly smaller proportion of words beginning with middle-developing phonemes compared to the TDL group. Initial phonemes produced in the lexicons of LTs are, in general, similar to both language-matched and age-matched typical toddlers and reflect lexical selection. Clinical implications of these findings will be discussed.

Environmental variability promotes the evolution of cooperation among geographically dispersed groups on dynamic networks

The evolutionary process that led to the emergence of modern human behaviors during the Middle Stone Age in Africa remains enigmatic. While various hypotheses have been proposed, we offer a new perspective that integrates the variability selection hypothesis (VSH) with the evolution of cooperation among human groups. The VSH suggests that human adaptability to fluctuating environments was a primary force driving the development of key evolutionary traits. However, the mechanisms by which environmental variability (EV) influenced human evolution, particularly the emergence of large-scale and complex cooperative behaviors, are not yet fully understood. To explore the connection between intensified EV and the evolution of intergroup cooperation, we analyzed three stochastic models of EV: (i) Regional Variability (RV), where resource-rich areas shift while overall resource levels remain stable; (ii) Universal Variability (UV), where overall resource levels fluctuate but resource-rich areas remain stable; and (iii) Combined Variability (CV), where both resource-rich areas shift and overall resource levels fluctuate. Our results show that RV strongly promotes cooperation, while UV has a comparatively weaker effect. Additionally, our findings indicate that the coevolution of cooperation and network structures is crucial for EVs to effectively promote cooperation. This study proposes a novel causal link between EV and the evolution of cooperation, potentially setting a new direction for theoretical and empirical research in this field.

Guidelines for testing hypotheses: A case study of episodic crustal production versus supercontinent-linked selective preservation

From a big picture perspective, the major components of scientific research include metaphysics, scientific paradigms, scientific hypotheses, scientific data, and tolerance toward various ideas. Based on these components, six guidelines are established for conducting geological research: awareness of underlying assumptions, development of falsifiable hypotheses, testing hypotheses, tolerance of competing hypotheses, replicating results, and obtaining representative sampling. Using these guidelines, a case study follows, which reviews empirical tests of the episodic crustal production hypothesis and the supercontinent-linked selective preservation hypothesis. The results support the episodic crustal production hypothesis while falsifying two key postulates of the selective preservation hypothesis.

Explaining immigrant–native differences in health at birth: The role of immigrant selectivity in Spain

Evidence shows that immigrants are often in better health than the native born—the so-called ‘immigrant health paradox’—and this advantage may extend to their children’s health. A commonly cited but rarely tested explanation is the ‘selectivity hypothesis’, positing that immigrants are healthier due to selection at origin based on health or socio-economic status (SES). Using 2007–19 Spanish birth registries, we investigate immigrant–native gaps in health at birth and whether they are explained by immigrants’ educational selectivity. We find that babies born to immigrants are less likely to be low birthweight (LBW) but are disadvantaged in terms of macrosomia and gestational age. Selectivity is associated with reduced LBW even after accounting for parental SES, explaining the lower risk among children of Northern African and Latin American immigrants but not across other parental country-of-birth groups. Selectivity is not associated with other birth outcomes. We confirm the selectivity hypothesis but question its universality across groups and health outcomes.

She’s everything: reactions to and perceptions of the Barbie (2023) movie as subversive and disparagement humor

Abstract Our study examined individuals’ reactions to and perceptions of the Barbie (2023) movie as subversive (e.g., targeting the United States patriarchal structure) versus disparaging (e.g., perpetuating negative perceptions of men/women). More specifically, we examined how various attitudes (e.g., ambivalent sexism, adherence to traditional gender roles, feminist attitudes) related to individuals’ decision to see Barbie, their expectations for and enjoyment of the movie, and their perceptions of its use of subversive humor for social commentary. Participants (N = 446, 71 % women, 79 % heterosexual, 78 % White, 65 % first-year students, M age = 19.40, SD = 3.25) were recruited from undergraduate courses from several Midwestern universities and completed a survey via Qualtrics. In line with our Selective Exposure Hypothesis, individuals with more egalitarian gender beliefs (e.g., higher levels of feminism, lower levels of sexism) were more likely to have seen Barbie. Similarly, in line with our Motivated Cognition Hypothesis, individuals with more egalitarian gender beliefs had more positive perceptions of Barbie, its messages, and intentions. Our findings further suggest that individuals who disagreed with Barbie’s message may have avoided viewing the movie, and if they did not avoid it, they may have resisted its message. This research furthers our understanding of subversive humor in relation to gender issues by examining how it was perceived in Barbie, one of the most significant pop culture events of the 2020s thus far.

Peran Profitabilitas dalam Memediasi Nilai Perusahaan Sektor Makanan dan Minuman (The Role of Profitability in Mediating Value of Food and Beverage Companies)

This study aims to analyze the role of profitability as a mediating variable in the relationship between capital structure and dividend policy on firm value. To achieve these objectives, the population used in this study is the annual financial statements of food and beverage sector companies listed on the Indonesia Stock Exchange during the 2019-2023 period. The sampling technique is purposive sampling. The data obtained were analyzed using Eviews 12 software, including model selection test, hypothesis testing, and Sobel test. The results show that capital structure, dividend policy, and profitability have no significant effect on firm value. In addition, profitability is negatively and significantly affected by capital structure and dividend policy, but cannot mediate the relationship between capital structure and dividend policy with firm value.

Fast and slow errors: What naming latencies of errors reveal about the interplay of attentional control and word planning in speeded picture naming.

Speakers sometimes produce lexical errors, such as saying "salt" instead of "pepper." This study aimed to better understand the origin of lexical errors by assessing whether they arise from a hasty selection and premature decision to speak (premature selection hypothesis) or from momentary attentional disengagement from the task (attentional lapse hypothesis). We analyzed data from a speeded picture naming task (Lampe et al., 2023) and investigated whether lexical errors are produced as fast as target (i.e., correct) responses, thus arising from premature selection, or whether they are produced more slowly than target responses, thus arising from lapses of attention. Using ex-Gaussian analyses, we found that lexical errors were slower than targets in the tail, but not in the normal part of the response time distribution, with the tail effect primarily resulting from errors that were not coordinates, that is, members of the target's semantic category. Moreover, we compared the coordinate errors and target responses in terms of their word-intrinsic properties and found that they were overall more frequent, shorter, and acquired earlier than targets. Given the present findings, we conclude that coordinate errors occur due to a premature selection but in the context of intact attentional control, following the same lexical constraints as targets, while other errors, given the variability in their nature, may vary in their origin, with one potential source being lapses of attention. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Testing Of Hypothesis for Model Selection

Testing Of Hypothesis for Model Selection

The 'sexual selection hypothesis' for the origin of aposematism.

The evolution of aposematism, in which prey exhibit conspicuous signals indicating the presence of anti- predator defenses, is puzzling. Before predators learn to associate the signal with defense, increased visibility makes the conspicuous prey highly vulnerable to predation. Although several hypotheses have been proposed to explain the evolution of aposematism, they often assume that these signals can only be recognized by predators. Yet, many studies show that aposematic signals can also be involved in mate choice. Here, we demonstrate that some aposematic signals may have originally evolved as mating signals driven by sexual selection. In this study, we analyze a mathematical model to explore how sexual selection can drive the evolution of aposematism. We thereby identify key features of this 'sexual selection hypothesis' for the origin of aposematism to be tested with empirical data. Our results show that the evolution of conspicuous signals through sexual selection increases the visibility of prey to predators and thus predation pressure. This, in turn, promotes the evolution of defense mechanisms, ultimately leading to aposematism when predators learn to associate the signal with defense. Additionally, we show that when sexual selection drives the evolution of aposematism, it often results in sexual dimorphism in both signaling and defense traits.

Lek Habitat Selection by Sympatric Manakin Species in Northwestern Ecuador.

Habitat selection plays a fundamental role in determining community structure and species coexistence, although the role played by sexual selection in shaping settlement patterns is less well understood. Manakins (Pipridae) are a Neotropical family of lekking birds that exhibit similar behavioral ecology across species, both in terms of resource use and dependence on elaborate visual signaling for mate attraction, yet they differ in the form of their sexually selected displays and ornaments. We characterized and compared the spatial dispersion and habitat attributes of lek sites for four species of sympatric manakins in the Chocó region of northwestern Ecuador to test several hypotheses for habitat selection and lek dispersion. First, the interspecific hotspot hypothesis predicts that ifmales establishleks in locations where females are likely to be encountered (e.g., resource-rich patches, topographic channels), then leks of ecologically similar species should cluster in geographic space due to shared patterns of resource use among species. Alternatively, the habitat partitioning hypothesis predicts leks of ecologically similar species to exhibit uniform spatial distributions to minimize competition for shared resources. Finally, the signal enhancement hypothesis proposes that males should establish leks in habitats with ambient light or structural properties optimal for the transmission or production of species-specific mating signals, and thus leks of different species should segregate in environmental space. We found that leks of sympatric manakin species were randomly distributed in geographic space, inconsistent with the interspecific hotspot and habitat partitioning hypotheses. In addition, manakin species segregated in environmental space based on forest structure characteristicsrelated to visual signaling. These findings suggest that landscape-level lek site dispersion by sympatric manakins may be primarily influenced by sexual display optimization rather than mechanisms related to their shared ecology. Moreover, this study flags the local population of Masius chrysopterus as a potential conservation concern due to its distinct and limited elevational preferences.

Nivolumab adjuvant to chemo-radiation in localized muscle-invasive urothelial cancer: primary analysis of a multicenter, single-arm, phase II, investigator-initiated trial (NEXT)

BackgroundMuscle-invasive urothelial cancer (UC) has a high risk of recurrence after definitive treatment. Nivolumab adjuvant to radical surgery improves disease-free survival in patients with UC with a high risk of...

Developmental Plasticity and the Evolutionary Rescue of a Colonizing Mite.

Plasticity, especially in small newly founded populations, can expose genetic variation to selection during the evolutionary rescue of populations, allowing individuals to achieve a phenotype with which they can survive. However, developmental plasticity can also enable organisms to accommodate perturbations, generating new phenotypic variation. We explored whether, at the start of a colonization event, phenotype dynamics follow a "selective" process in which plasticity fuels evolutionary rescue or whether they are due to developmental plasticity in a "generative" process. We investigated this using the bulb mite Rhizoglyphus robini, which expresses a facultative, juvenile dispersal phenotype (deutonymph) under unfavorable conditions and shows alternative adult male phenotypes: competitive fighters or benign scramblers that are expressed to mitigate food stress and which have higher levels of genetic heterozygosity than fighters. Mimicking colonization dynamics, we founded small, medium and large populations from deutonymphs on low or high food to test if scramblers were expressed earliest postcolonization within (i) the smallest founder populations to alleviate inbreeding (selective hypothesis), or (ii) the largest founder populations as a direct consequence of food stress is highest due to higher food competition (generative hypothesis). In line with the generative hypothesis under both food environments, scramblers were expressed at the earliest in the largest founder populations, which also tended to show the lowest growth at the start of the experiment and had the lowest ultimate population size. Our findings highlight the necessity to seek explanations of how developmental pathways likely influence evolutionary rescue patterns, starting with how resource limitation (stress) shapes adaptive responses during colonization.

Linking behavioural variance to environmental heterogeneity: Variance decomposition in surface versus cave isopod populations

Abstract A longstanding question in evolutionary biology is how within‐population phenotypic variation is maintained under natural selection. The fluctuating selection hypothesis suggests that genetic and phenotypic variation scales with fluctuations in selection over space and time. This implies that phenotypic variation might be greater in populations with fluctuating than stable environmental conditions. However, this aspect has rarely been investigated, likely because habitats with minimal fluctuations are rare. We addressed this hypothesis by comparing surface and cave populations of the freshwater isopod Asellus aquaticus species complex. Surface environments are spatiotemporally more variable than cave environments, grounding the prediction that the surface ecotype is phenotypically more variable than the cave ecotype. We conducted a longitudinal behavioural study on individuals from four surface and four cave populations, measuring their movement activity and risk‐taking in two light conditions. To account for differences in the natural light regimes between surface and cave populations, half of the individuals were first acclimated under a diurnal light regime and the other half in complete darkness. Initially (acclimation tests), their behaviour was recorded in bright and dark light conditions, respectively. Next, each individual was evaluated six times in alternating light conditions—three times in each light condition. In addition to assessing average differences, we estimated among‐ and within‐individual variation, as well as repeatability and light‐induced plasticity in behaviours, enabling a comparison of these parameters between the two ecotypes. In the dark, surface individuals were on average more active and less risk‐taking than cave individuals. As predicted, the surface compared with the cave ecotype displayed greater among‐ and within‐individual variance in movement activity, but not in risk‐taking. Repeatability was not significantly different between ecotypes. Both ecotypes showed significant among‐individual variation for light‐induced plasticity in both behaviours, however, plasticity did not differ between ecotypes. Our results also suggest that more active or risk‐taking individuals exhibited greater plasticity. Our findings support the hypothesis that fluctuating selection plays a role in maintaining variation for movement activity but not for risk‐taking. Read the free Plain Language Summary for this article on the Journal blog.

Clinical significance of lipid pathway-targeted therapy in breast cancer.

Globally, breast cancer represents the most common cancer and the primary cause of death by cancer in women. Lipids are crucial in human physiology, serving as vital energy reserves, structural elements of biological membranes, and essential signaling molecules. The metabolic reprogramming of lipid pathways has emerged as a critical factor in breast cancer progression, drug resistance, and patient prognosis. In this study, we delve into the clinical implications of lipid pathway-targeted therapy in breast cancer. We highlight key enzymes and potential therapeutic targets involved in lipid metabolism reprogramming, and their associations with cancer progression and treatment outcomes. Furthermore, we detail the clinical trials exploring the anticancer and cancer chemopreventive activity of therapies targeting these molecules. However, the clinical efficacy of these therapies remains controversial, highlighting the urgent need for predictive biomarkers to identify patient subpopulations likely to benefit from such treatment. We propose the Selective Lipid Metabolism Therapy Benefit Hypothesis, emphasizing the importance of personalized medicine in optimizing lipid pathway-targeted therapy for breast cancer patients.

Does Differential Habitat Selection Facilitate Coexistence Between Badgers and Hedgehogs?

Predicting the spatial and temporal responses of species exhibiting intraguild predation (IGP) relationships is difficult due to variation in potential interactions and environmental context. Eurasian badgers (Meles meles) are intraguild predators of European hedgehogs (Erinaceus europaeus) and are implicated in their population decline via both direct predation and competition for shared food resources. Previous studies have shown spatial separation between these species and attributed this to hedgehogs experiencing a 'landscape of fear', but little is known about the potential role of differential habitat use. We estimated the density and occupancy of both species at 22 rural study sites in England and Wales, to explore whether food availability, habitat or the presence of badgers, explained hedgehog distributions. Hedgehog density varied significantly across major rural land uses, whereas badger density did not. Although both species coexisted at a regional (1 km2) scale, occupancy modelling showed spatial segregation at a finer (individual camera trap) scale, associated with differential habitat use. In contrast to badgers, hedgehogs were recorded near buildings, and in areas supporting lower invertebrate biomass. This is in agreement with IGP theory, whereby IG-prey may occupy suboptimal habitat to avoid predation; however, hedgehog habitat use did not vary relative to the presence of badgers. Badger and hedgehog temporal activity showed no evidence of separation. Although these findings are consistent with hedgehogs avoiding badgers via a landscape of fear, they are also indicative of differential habitat use, highlighting the need for more holistic studies considering variation in habitat selection and food availability when investigating intraguild relationships. Future studies exploring alternative hypotheses for urban habitat selection by hedgehogs are needed to better understand how possible spatial niche partitioning may support their coexistence with badgers in some areas.

Trans-Specific Polymorphisms Between Cryptic Daphnia Species Affect Fitness and Behavior.

Shared polymorphisms, loci with identical alleles across species, are of unique interest in evolutionary biology as they may represent cases of selection maintaining ancient genetic variation post-speciation, or contemporary selection promoting convergent evolution. In this study, we investigate the abundance of shared polymorphism between two members of the Daphnia pulex species complex. We test whether the presence of shared mutations is consistent with the action of balancing selection or alternative hypotheses such as hybridization, incomplete lineage sorting or convergent evolution. We analyzed over 2,000 genomes from six taxa in the D. pulex species group and examined the prevalence and distribution of shared alleles between the focal species pair, North American and European D. pulex. We show that North American and European D. pulex diverged over 10 million years ago, yet retained tens of thousands of shared polymorphisms. We suggest that the number of shared polymorphisms between North American and European D. pulex cannot be fully explained by hybridization or incomplete lineage sorting alone. We show that most shared polymorphisms could be the product of convergent evolution, that a limited number appear to be old trans-specific polymorphisms, and that balancing selection is affecting convergent and ancient mutations alike. Finally, we provide evidence that a blue wavelength opsin gene with trans-specific polymorphisms has functional effects on behavior and fitness in the wild.

Abstract IA008: Leveraging conformational dynamics for improved selectivity

Abstract Maximizing the clinical activity and combinability of oncogene inhibitors requires the development of molecules that can achieve necessary levels of target inhibition at a tolerated and feasible human dose. This is enabled by improving selectivity against off-targets and/or for the mutant form of the target over wild-type. While conventional structural insights can inform the design of selective drug candidates, there are often cases where clear selectivity hypotheses are not readily identifiable. Here, we present two examples illustrating how conformational dynamics can be leveraged to obtain improved selectivity for validated oncogene targets. The first example focuses on the selective inhibition of FGFR2, a well-established target in various cancers harboring FGFR2 fusions or rearrangements. Although clinical efficacy of pan-FGFR inhibitors has been demonstrated, their benefit is limited by FGFR1- and FGFR4- mediated toxicities. We leveraged differences in conformational dynamics between FGFR2 and other FGFRs observed through molecular dynamics simulations to enable the development of Lirafugratinib, the first FGFR2 selective inhibitor. Lirafugratinib inhibits FGFR2 with a high degree of selectivity in pre-clinical models. In cancer patients, Lirafugratinib achieves >95% FGFR2 occupancy at a dose of 70mg once daily, with minimal evidence of inhibition of other FGFR isoforms. This improved selectivity translates to higher objective response rates compared to pan-FGFR inhibitors across multiple tumor types harboring FGFR2 fusions or rearrangements. The second example illustrates mutant-selective targeting of PI3Kα, the most frequently mutated kinase in cancer. While non-mutant selective inhibitors have shown clinical efficacy, their benefit is limited by hyperglycemia caused by inhibition of wild-type PI3Kα. Conformational differences between mutant and wild-type PI3Kα were identified using structural insights combined with molecular dynamics simulations, leading to the discovery of RLY-2608- the first mutant-selective inhibitor of PI3Kα. RLY-2608 binds to a novel allosteric pocket and demonstrates mutant selective inhibition in pre-clinical models. RLY-2608 has a favorable pharmacokinetic profile in cancer patients, with dose-dependent increases in exposure and low peak to trough fluctuations, resulting in high levels of target coverage throughout the dosing interval. When combined with fulvestrant, this translates into a higher objective response rate and lower rate of hyperglycemia in patients with hormone-receptor positive, PI3Kα-mutant breast cancer compared to non-mutant selective PI3Kα inhibitors. These examples demonstrate the power of leveraging conformational dynamics to obtain selective target inhibition, ultimately translating into improved patient outcomes. Citation Format: James Watters. Leveraging conformational dynamics for improved selectivity [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Optimizing Therapeutic Efficacy and Tolerability through Cancer Chemistry; 2024 Dec 9-11; Toronto, Ontario, Canada. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(12_Suppl):Abstract nr IA008.

The effect of instructed refreshing on working memory: Is the memory boost a function of refreshing frequency or refreshing duration?

AbstractRefreshing is assumed to reactivate the contents of working memory in an attention-based way, resulting in a boost of the attended representations and hence improving their subsequent memory. Here, we examined whether the refreshing-induced memory boost is a constant or a gradual, time-dependent phenomenon. If the beneficial effect of refreshing on memory performance is due to the information being selected for refreshing (i.e., selection hypothesis), a constant memory boost is expected to occur each time an item is selected for refreshing, with better memory performance for items that are selected more often. If, however, the beneficial effect of refreshing on memory performance is due to spending time in the focus of attention during refreshing (i.e., duration hypothesis), a gradual memory boost is expected, with the size of the memory boost being a direct function of how long the item has been the object of focused attention. To distinguish between these hypotheses, we instructed and guided the use of refreshing during retention through the presentation of cues, and varied the number of refreshing steps and their duration independently. The number of refreshing steps, but not their duration, had an effect on recall, in agreement with the selection hypothesis. However, some of the results were less robust than anticipated, indicating that the effect of instructed refreshing is limited to certain task parameters.

Sexual size dimorphism as a determinant of biting performance dimorphism in Anolis lizards.

Rensch's rule describes a pattern of interspecific allometry in which sexual size dimorphism (SSD) increases with size among closely related species (i.e., among a group of related species, the largest ones tend to show more male-biased SSD). Sexual selection is often invoked to explain Rensch's rule, as larger male body size is assumed to be favoured by sexual selection for increased fighting performance in contests for mating opportunities. Often, however, the correlation between size and performance is not well described. We studied a sexually selected performance trait, bite force in Anolis lizards, to determine whether patterns of SSD are linked to size-associated patterns of performance dimorphism at the macroevolutionary level, as expected under the sexual selection hypothesis for Rensch's rule. Additionally, we tested whether allometric patterns of performance dimorphism differ between mainland and island species, as the latter have likely evolved under a stronger sexual selection regime. We found that SSD overwhelmingly explains the relationship between performance dimorphism and size in anoles, as expected under a sexual selection model for Rensch's rule. However, residual performance dimorphism was higher in island than in mainland species, suggesting that these groups differ in performance dimorphism for reasons unrelated to size. Head size dimorphism was associated with residual performance dimorphism, but did not fully explain the difference in performance dimorphism between island and mainland species. Together, these findings highlight the need to interpret Rensch's rule patterns of body size evolution cautiously, as allometric patterns of performance dimorphism and size dimorphism might not be equivalent.

Bayesian hierarchical hypothesis testing in large-scale genome-wide association analysis.

Variable selection and large-scale hypothesis testing are techniques commonly used to analyze high-dimensional genomic data. Despite recent advances in theory and methodology, variable selection and inference with highly collinear features remain challenging. For instance, collinearity poses a great challenge in genome-wide association studies involving millions of variants, many of which may be in high linkage disequilibrium. In such settings, collinearity can significantly reduce the power of variable selection methods to identify individual variants associated with an outcome. To address such challenges, we developed a Bayesian hierarchical hypothesis testing (BHHT)-a novel multiresolution testing procedure that offers high power with adequate error control and fine-mapping resolution. We demonstrate through simulations that the proposed methodology has a power-FDR performance that is competitive with (and in many scenarios better than) state-of-the-art methods. Finally, we demonstrate the feasibility of using BHHT with large sample size (n∼ 300,000) and ultra dimensional genotypes (∼ 15 million single-nucleotide polymorphisms or SNPs) by applying it to eight complex traits using data from the UK-Biobank. Our results show that the proposed methodology leads to many more discoveries than those obtained using traditional SNP-centered inference procedures. The article is accompanied by open-source software that implements the methods described in this study using algorithms that scale to biobank-size ultra-high-dimensional data.