American Naturalist最新文献

The Evolution of Homeothermic Endothermy via Life History Optimization. 基于生命史优化的恒温动物进化。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-06-20 DOI: 10.1086/736225

Juan G Rubalcaba

{"title":"The Evolution of Homeothermic Endothermy via Life History Optimization.","authors":"Juan G Rubalcaba","doi":"10.1086/736225","DOIUrl":"10.1086/736225","url":null,"abstract":"AbstractEndothermy is an energetically expensive trait, yet it has posed an evolutionary advantage across different lineages-a paradox that remains puzzling to biologists. Here, I investigate whether endothermy can evolve through life history optimization using a model of the balance between energy assimilation and energy allocation to somatic maintenance, thermoregulation, growth, or reproduction. The model displays bistable strategies when assimilation rates and thermoregulatory costs increase, respectively, exponentially and linearly with body temperature: the \"heterothermic strategy\" consists of minimizing the costs of thermoregulation by maintaining body temperature close to ambient temperature, and the \"homeothermic strategy\" consists of increasing body temperature until the costs of thermoregulation are fully compensated by the increased assimilation capacity at higher temperatures. These strategies produce similar fitness outcomes and thus emerge as alternative stable states of the system, maintained by strong stabilizing selection preventing transitions between them. Using quantitative genetics simulations, I show that a drop in ambient temperature may push populations toward an evolutionary branching point, enabling the rapid radiation of homeothermic lineages coupled with body size reductions. I thus propose that life history optimization of energy balance can explain the radiation of homeothermic endothermy associated with either climate cooling or migration to colder regions by early endothermic lineages.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"150-159"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Phenology of Leaf Litter Decomposition in Aquatic and Terrestrial Compartments of Headwater Catchments. 水源集水区和陆区凋落叶分解的物候特征。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-06-27 DOI: 10.1086/736356

Eva Cereghetti, Florian Altermatt

{"title":"The Phenology of Leaf Litter Decomposition in Aquatic and Terrestrial Compartments of Headwater Catchments.","authors":"Eva Cereghetti, Florian Altermatt","doi":"10.1086/736356","DOIUrl":"10.1086/736356","url":null,"abstract":"AbstractThe decomposition of leaf litter is a major ecological process in terrestrial and aquatic ecosystems worldwide. Leaf litter generally enters ecosystems in annual pulses and is subsequently decomposed across many seasons. Yet investigations into this process are rarely conducted in parallel in aquatic and terrestrial ecosystems and over the full year, limiting our understanding of its phenological context across the blue-green interface. Here, we assessed the decomposition of three litter species by microorganisms and macroinvertebrates in temperate streams and forests across a year using repeated litterbag assays at 6-week intervals. We observed higher decomposition rates in summer in most combinations of ecosystem, litter species, and decomposer type, indicating positive effects of higher temperatures and low standing crops of labile litter. Furthermore, forests showed lower decomposition rates than streams. Last, we found that the relative litter species effects on both microbial and invertebrate decomposition were consistent across environments, suggesting that the fast microbial activity decreased the quality of the remaining tissue mass for invertebrates. Overall, our work places known drivers of the decomposition of leaf litter into a phenological context, providing evidence that changes in the timing or strength of these drivers could drive temporal shifts of this central ecological process.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"89-100"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A New Twist on an Old Story: Pollination and Seed Predation in Jadera haematoloma. 一个古老故事的新转折：红足锦囊藻的授粉和种子捕食。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-06-11 DOI: 10.1086/736460

Mattheau S Comerford, Scott P Carroll, Scott P Egan

引用次数: 0

Best Publishing Practices and Open Access Options at The American Naturalist. 美国自然主义者的最佳出版实践和开放获取选项。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-06-24 DOI: 10.1086/736548

Volker H W Rudolf, Jill T Anderson, Sébastien Lion

引用次数: 0

Food Web Structure Mediates Positive and Negative Effects of Diversity on Ecosystem Functioning in a Large Floodplain River. 食物网结构对大河漫滩河流生态系统功能的正向和负向影响

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-06-16 DOI: 10.1086/735914

Dalmiro Borzone Mas, Pablo A Scarabotti, Patricio Alvarenga, Pablo A Vaschetto, Matías Arim

{"title":"Food Web Structure Mediates Positive and Negative Effects of Diversity on Ecosystem Functioning in a Large Floodplain River.","authors":"Dalmiro Borzone Mas, Pablo A Scarabotti, Patricio Alvarenga, Pablo A Vaschetto, Matías Arim","doi":"10.1086/735914","DOIUrl":"10.1086/735914","url":null,"abstract":"AbstractThe biodiversity-ecosystem functioning (BEF) and the food web structure (FWS) theories are cornerstones of contemporary ecology. However, while several theoretical hypotheses predict a link between BEF and FWS, the integration of both frameworks has only recently been considered. In this study, we applied structural equation models to evaluate 73 sink food webs of predatory fish from the Paraná River, encompassing a wide gradient of community richness. Our analysis revealed a well-supported causal model where species richness drives food web structure, increasing link density, modularity, intermodular connections, and weak interactions while decreasing nestedness. Both link density and modularity were positively associated with standing biomass, suggesting that communities with multiple energy pathways and strong complementarity effects tend to support higher biomass. Surprisingly, while species richness had the largest overall effect on biomass, this effect was indirect, mediated through three positive pathways and one negative pathway. These findings highlight the complex associations between BEF and FWS, suggesting that anthropogenic impacts on modularity, such as community functional homogenization, could shift positive BEF effects to negative, with cascading consequences for entire ecosystems.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"115-129"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inbreeding and Competitor's Genetic Relatedness Affect Dynamic Male Color Ornament Expression in a Cichlid Fish. 近亲繁殖和竞争对手的遗传亲缘关系影响慈鲷动态雄性色彩装饰的表达。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-07-07 DOI: 10.1086/736181

Leonie Gussone, Simon Vitt, Timo Thünken

{"title":"Inbreeding and Competitor's Genetic Relatedness Affect Dynamic Male Color Ornament Expression in a Cichlid Fish.","authors":"Leonie Gussone, Simon Vitt, Timo Thünken","doi":"10.1086/736181","DOIUrl":"10.1086/736181","url":null,"abstract":"AbstractOrnamental traits signaling phenotypic and/or genetic quality play a central role in sexual selection and greatly determine the access to mating partners and thus fitness. Accordingly, they underlie strong directional selection. Ornament expression is often condition dependent and therefore supposed to be sensitive to inbreeding. Kin selection theory predicts that ornament expression may depend on the genetic relatedness of competitors. Here, we examined the dynamic color expression in male groups of the cichlid Pelvicachromis taeniatus during competition over breeding sites. Groups (trios) were either inbred or outbred, and each consisted of two unfamiliar brothers and an unfamiliar unrelated male. Males of P. taeniatus are territorial and develop a carotenoid-based yellow coloration at the ventral body region and the caudal fin. Intense body coloration signals dominance. Our study showed (i) that outbred males generally developed more intense yellow coloration (chromaticity) during the experiment compared with inbred males and (ii) that related males were more intensively colored at the caudal fin after the trials than the unrelated males. In conclusion, our study indicates environment-dependent inbreeding depression in a male ornament as well as positive kin-selected effects on ornament expression. Our study describes understudied sources of phenotypic variation in ornamental traits in animals.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"160-170"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Means of Signal Divergence Early in a Host Shift. 主机移位早期信号发散的方法。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-07-02 DOI: 10.1086/736182

Rafael L Rodríguez, Thomas K Wood, Frank W Stearns, Robert L Snyder, Kelley J Tilmon, Michael S Cast, Randy E Hunt, Reginald B Cocroft

{"title":"The Means of Signal Divergence Early in a Host Shift.","authors":"Rafael L Rodríguez, Thomas K Wood, Frank W Stearns, Robert L Snyder, Kelley J Tilmon, Michael S Cast, Randy E Hunt, Reginald B Cocroft","doi":"10.1086/736182","DOIUrl":"10.1086/736182","url":null,"abstract":"AbstractWe used a \"quasi-natural\" selection experiment and subsequent reciprocal transplants to assess the means of divergence in mating signals early in a host shift. We worked with a member of the Enchenopa binotata complex of treehoppers (Hemiptera: Membracidae), where speciation results from host plant shifts and involves remarkable signal-preference codivergence. We shifted treehoppers from a natural population on one host plant to three different novel host species under conditions of allopatry and sympatry. After five generations, we conducted reciprocal transplants that manipulated oviposition and development hosts. We found tentative evidence of signal divergence fueled by standing genetic variation and strong evidence of signal divergence through overall plasticity and evolution in the form of plasticity, resulting in signal differences between treehoppers on novel and ancestral hosts. These results suggest that signal divergence (and consequently assortative mating) may arise early in a host shift from multiple means. Together with a prior analysis of the adaptive consequences of these experimental host shifts, our findings indicate that adaptation/specialization and divergence in sexual traits may originate independently and in parallel or with divergence in sexual traits leading. Thus, ecological specialization may be facilitated by sexual divergence rather than being the initiating factor.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"130-149"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Chemical Mate Choice Copying in Drosophila melanogaster. 黑腹果蝇的化学配偶选择复制。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-06-26 DOI: 10.1086/736329

Bloo Mitchell, Alexandria Abbott, Ashanti Brown, Lacy N Skinner, Elmira Umarova, Philip Kohlmeier

{"title":"Chemical Mate Choice Copying in Drosophila melanogaster.","authors":"Bloo Mitchell, Alexandria Abbott, Ashanti Brown, Lacy N Skinner, Elmira Umarova, Philip Kohlmeier","doi":"10.1086/736329","DOIUrl":"10.1086/736329","url":null,"abstract":"AbstractMate choice is a critical decision, especially for females, that requires time and energy to assess potential partners' genetic quality. Consequently, in many species, females have evolved the ability to utilize social information by copying the mate choices of others, usually based on visual cues. However, many species, especially invertebrates, primarily rely on chemical not visual cues. Using chemical rather than visual cues provides several advantages, such as not requiring active observation of copulations. Despite that, empirical evidence for the existence of chemical mate choice copying is scarce. Using Drosophila melanogaster, we provide the first demonstration of chemical mate choice copying. Females exposed to a recently mated female select the same male genotype that the demonstrator female mated with at a higher frequency than expected by chance. Chemical mate choice copying requires sensing both male and female cues, which might indicate that other females have chosen that male genotype. Our work suggests that females, in the presence of mated females, increase choosiness at the virgin stage, elevating sexual selection on male traits. This study provides novel evidence that exploiting social information is more prevalent in flies than previously assumed.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"171-178"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

No Evidence for Paternal Age Effects on Sons or Daughters When Accounting for Paternal Sperm Storage. 当考虑父亲精子储存时，没有证据表明父亲年龄对儿子或女儿的影响。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-07-02 DOI: 10.1086/736479

Krish Sanghvi, Samuel J L Gascoigne, Biliana Todorova, Regina Vega-Trejo, Tommaso Pizzari, Irem Sepil

{"title":"No Evidence for Paternal Age Effects on Sons or Daughters When Accounting for Paternal Sperm Storage.","authors":"Krish Sanghvi, Samuel J L Gascoigne, Biliana Todorova, Regina Vega-Trejo, Tommaso Pizzari, Irem Sepil","doi":"10.1086/736479","DOIUrl":"10.1086/736479","url":null,"abstract":"AbstractA father's age at conception is predicted to affect not only his own fertility but also his offspring's fitness. Offspring born to old fathers are assumed to be less fit than those of young fathers. However, under low mating rates, paternal age might be confounded with the duration for which mature sperm are stored in fathers prior to ejaculation. Studies that disentangle the confounding paternal effects of sperm storage duration from those of age on offspring are lacking. We use Drosophila melanogaster to test the separate and interactive effects of paternal age and sexual rest on offspring fitness. As expected, old fathers produce fewer offspring than young fathers; however, paternal age does not influence the survival or age-dependent reproductive success of sons or daughters. Instead, a long duration of paternal sexual rest negatively impacts the reproductive success of the conceived sons. Furthermore, daughters of low reproductive quality selectively disappear with age, but sons do not, highlighting that demographic processes can further modulate paternal age effects. Overall, we highlight that paternal age effects might not be as pervasive as previously assumed and suggest that paternal sexual rest might be more important in influencing offspring phenotypes.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"E29-E46"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Bird Species' Network Centrality Varies Differentially across Species within Their Climatic Niches. 鸟类的网络中心性在不同物种的气候生态位中存在差异。

IF 2.7 2区环境科学与生态学

American Naturalist Pub Date : 2025-08-01 Epub Date: 2025-06-16 DOI: 10.1086/736357

Gabriel M Moulatlet, Wesley Dáttilo, W Daniel Kissling, Fabricio Villalobos

{"title":"Bird Species' Network Centrality Varies Differentially across Species within Their Climatic Niches.","authors":"Gabriel M Moulatlet, Wesley Dáttilo, W Daniel Kissling, Fabricio Villalobos","doi":"10.1086/736357","DOIUrl":"10.1086/736357","url":null,"abstract":"AbstractUnderstanding how the functional role of species within seed dispersal networks varies across geographical and climatic gradients can reveal the drivers of network organization. Because bird-plant interactions differ depending on where these occur, species' centrality (a measurement of species importance in the networks) is expected to vary across species' geographic distributions. Using a global dataset of bird-plant seed dispersal networks, we applied a cross-random mixed effects model to evaluate the variation of 239 bird species' centrality within local networks across their occupied climatic conditions and in response to coexisting bird and plant diversities in those networks. Our model indicated that centrality did not vary significantly with the distance to the climatic niche centroid but increased with increasing bird diversity. However, by examining species' individual responses we found that centrality did vary with the distance to the climatic niche centroid: 43% of the evaluated species (102) showed a negative relationship (higher centrality closer to the climatic niche centroid), whereas 51% of species (122) showed a positive relationship (higher centrality farther from the climatic niche centroid). The effect of bird diversity on individual species' centrality covaried positively with that of plant diversity more than having opposite effects, regardless of the network's position within the climatic niche. Taken together, the variation in individual species' centrality within the occupied climatic conditions suggests the existence of areas where species achieve high centrality, which might form the substrate for evolutionary and ecological dynamics.","PeriodicalId":50800,"journal":{"name":"American Naturalist","volume":"206 2","pages":"101-114"},"PeriodicalIF":2.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144735100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0