BMC ecology and evolution最新文献

Background: Global warming and extreme weather events driven by greenhouse gas emissions are significantly impacting fish survival and reproduction, leading to dramatic consequences for marine biodiversity and ecosystem stability. Comparative analysis of closely related species from a phylogenetic perspective provides valuable insights for biodiversity conservation efforts. The study investigates the effects of climate change on the suitability of habitat and ecological vulnerability of two important sibling fishes, Collichthys lucidus and Collichthys niveatus, in the western Pacific.

Results: This study found that the main driver of ecological niche differences between the two species is the niche contraction of C. niveatus. Predictions from species distribution models indicate that C. lucidus has a wider distribution and greater adaptability under future climate scenarios. Both species will experience significant habitat loss and heightened ecological vulnerability in the southern Yellow Sea. Additionally, the two populations of C. lucidus in the Yangtze River estuary display different levels of ecological vulnerability. These two species also exhibit distinct responses to environmental factors such as temperature and chlorophyll concentration.

Conclusion: The study's findings indicate that climate change will accelerate the population differentiation of C. lucidus and the habitat loss of C. niveatus. These results underscore the importance of prioritizing the southern Yellow Sea in future research and emphasize the necessity of developing adaptive conservation strategies for both species.

Lygodactylus geckos represent a well-documented radiation of miniaturized lizards with diverse life-history traits that are widely distributed in Africa, Madagascar, and South America. The group has diversified into numerous species with high levels of morphological similarity. The evolutionary processes underlying such diversification remain enigmatic, because species live in different ecological biomes, ecoregions and microhabitats, while suggesting strikingly high levels of homoplasy. To underscore this evolutionary pattern, here we explore the shape variation of skull elements (i.e., cranium, jaw and inner ear) using 3D geometric morphometrics and phylogenetic comparative methods on computed tomography scans (CT-scan) of a sample encompassing almost all recognized taxa within Lygodactylus. The results of this work show that skull and inner ear shape variation is low (i.e., there is high overlapping on the morphospace) across geographic regions, macrohabitats and lifestyles, implying extensive homoplasy. Furthermore, we also found a strong influence of allometry shaping cranial variation both at intra and interspecific levels, suggesting a major constraint underlying skull architecture, probably as a consequence of its miniaturization. The remaining variation that is not allometric is independent of phylogeny and ecological adaptation and can probably be interpreted as the result of intrinsic developmental plasticity. This, in turn, supports the interpretation that speciation in this group is largely concordant with a non-adaptive hypothesis, which results mainly from vicariant processes.

Background: Citizen Science (CS) offers a promising approach to enhance data collection and engage communities in conservation efforts. This study evaluates the use of CS in environmental DNA (eDNA) monitoring for Mediterranean monk seal conservation. We validated CS by assessing the effectiveness of a newly developed CS-friendly filtration system called "WET" (Water eDNA Trap) in eDNA detection, addressing technical challenges, and analysing volunteer faults. The WET is a 4-litre, manual pump-based filtering system using positive pressure to force water through the filter. We also assessed the use of a retrospective questionnaire as a tool to measure CS's social impact on participants' perceived knowledge, attitudes, and conservation behaviours.

Results: Results suggest the WET performs comparably to traditional methods, with minor technical issues. Despite some faults such as not folding or forgetting to change the filter, volunteers were generally reliable in sample processing. Moreover, CS involvement increased participants' perceived knowledge, affective attitudes, and conservation behaviours towards seal conservation. Volunteers reported a greater understanding of eDNA monitoring, increased interest in monk seal conservation, and more frequent conservation behaviours, including spreading awareness within their community. While these findings are exploratory due to the small sample size (19 participants) and potential ceiling effects in attitude assessment, they provide an initial validation of the questionnaire as a tool for measuring CS's social outcomes. Future studies with larger sample sizes are needed to confirm these results and investigate their applicability across broader stakeholder groups. Continuous improvement in volunteer training and equipment design is also recommended.

Conclusions: This study highlights CS's potential to improve public engagement and knowledge in conservation. By involving diverse participants, CS can play a critical role in long-term conservation efforts and promote sustainable coexistence between humans and monk seals. Furthermore, the validation of the questionnaire offers a valuable framework for evaluating the social impact of CS initiatives in conservation contexts.

Background: Understanding local communities' knowledge and insights is essential for developing effective mitigation and adaptation strategies for climate change. The young generation often brings new perspectives on climate change, demonstrating a growing awareness of its impacts and innovative ideas for sustainable solutions. By engaging youth in climate action we foster future leadership, empowering them as active participants in shaping long-term climate resilience. Higher education plays a pivotal role in raising awareness about climate change and fostering environmentally responsible behaviour among citizens. Thus, the study assessed climate change indicators in Tanzania by gathering insights from university students, leveraging their understanding of the local challenges posed by climate change.

Results: Out of the 486 sampled students, 80% were aware of climate change and could identify its indicators in their home regions. The primary perceived indicators of climate change reported by the respondents included increasing temperatures, crop failures, and the disappearance of native plant species. Respondents from the coastal zone ranked rising temperatures and increased rainfall as the most significant indicators, while those from the Kilimanjaro region emphasised crop failure. Additionally, respondents from the central zone highlighted the disappearance of native plant species. Conversely, respondents from the arid central zone believed that climate change has resulted in reduced rainfall and an increase in drought occurrences. Furthermore, socio-demographic factors such as gender, home region, and academic year influenced students' awareness of climate change. A lower proportion (0.78) of male students demonstrated knowledge of climate change compared to female students (0.91) (p = 0.001). Additionaly, a lower proportion (0.71) of students from urban areas demonstrated knowledge of climate change compared to students from rural areas (0.85) (p < 0.001). Moreover, students in their final year of study exhibited greater awareness of climate change than those in lower years, highlighting the significance of the formal education system in imparting knowledge about climate change.

Conclusions: This study underscores the role of higher education in fostering climate awareness and youth engagement through education and outreach. Additionally, it supports SDG 13: "Climate Action" and SDG 4: "Quality Education by promoting informed participation and sustainable solutions among young people".

Background: The spotted hyena (Crocuta crocuta) is one of the carnivore species that frequently comes into conflict with humans. These conflicts are attributed to their scavenging foraging behaviour and their ability to occupy habitats close to human settlements. In Tanzania, the Geita region has recently experienced an increase in livestock and human attacks by hyenas. However, there are limited studies examining the extent of these attacks and the associated social-economic impacts. Thus, this study evaluated the social impacts and economic losses due to spotted hyena attacks in the Nyang'whale district in the Geita region.

Materials and methods: The study was carried out in three villages in the Nyang'whale district, namely Wavu, which is close to the Mienze Forest Reserve; Bukungu, which is far from the forest but surrounded by many hills; and Izunya, which is far from the forest and the hills. Data collection was done through household surveys, focus group discussions, and key informant interviews. A Chi-square test assessed the association between hyena fear and daily activities across villages. Poisson regression compared the number of livestock attacked by hyenas by village and species. Linear regression analysis compared financial losses due to livestock attacks and reductions in working time due to hyena fear across villages.

Results: There was a significant variation in the frequency of livestock and human attacks between the villages. The frequency of livestock attacks was lower in Bukungu village, but human attacks were highest in this village. The Wavu village, which is close to the forest, had the highest livestock number and attacks, but no human attacks were reported. The hyena attacks had created fear, which had changed the daily routines of the villagers. The village with the most human attacks reported a high rate of school dropouts, while the one with the most livestock attacks reported a reduction in sleeping time at night to watch livestock. Economic losses due to livestock attacks averaged $300.5 per household per year, while losses due to reduced working time were equivalent to $285.6 per household per year.

Conclusion: Given that villages with a large number of livestock experienced more livestock attacks and fewer human attacks, this suggests that hyenas may target humans when their food resources are limited. Therefore, conducting further studies to assess the hyena population and the availability of their natural prey is crucial for formulating effective intervention strategies. Additionally, villagers should be educated on ways to control human and livestock attacks based on the animals' ecology and behaviour.

Under the background of global climate change, climate warming has led to an increase in insect herbivory, which significantly affects the growth, survival, and regeneration of forest plants in the warm temperate zone of China. Plants can adopt defense responses to adapt to insect defoliation. Therefore, field experiments were conducted on five common warm temperate species, Quercus acutissima, Quercus serrata, Quercus aliena, Quercus dentata, and Robinia pseudoacacia. We measured the leaf traits of healthy trees and insect defoliated trees, to explore the response strategies of common species in warm temperate zones to insect defoliation. Our results showed that native species stored more carbon in extreme environments for survival rather than growth, while the alien species R. pseudoacacia tended to adopt active resource acquisition strategies and were more inclined towards growth. The content of tannins and flavonoids in the alien species R. pseudoacacia did not significantly increase after leaf damage, while the content of secondary metabolites such as tannins, flavonoids, and total phenols in the native species Q. acutissima, Q. serrata, Q. aliena, Q. dentata increased significantly after leaf damage. This indicated that compared to alien species, native species invested more resources in defense, which might reduce resource allocation for growth. Thus, the native Quercus species have stronger resistance than the alien species R. pseudoacacia after insect defoliation.

Background: Species generally exhibits evolutionary bias, adapting towards a specific direction rather than others, yet the underlying causes remains unknown.

Results: Here, we investigated evolutionary bias and its causes by conducting experimental evolution on Escherichia coli. We introduced an E. coli strain (lac-), initially unable to utilize lactose due to a frameshift mutation, into two different culture media: one medium (L) containing ample sodium acetate and lactose as carbon sources, and the other medium (G) containing abundant glucose and lactose as carbon sources. After 20 days of experimental evolution, our findings revealed that all L-populations underwent parallel evolution through reverse mutation to utilize lactose (lac+), resulting in a relatively higher fitness gain compared to utilizing sodium acetate. In contrast, all G-populations did not transition towards lactose utilization but instead continued to utilize glucose, which provides a higher fitness gain than utilizing lactose. These results demonstrate that our experimental populations in L and G media respectively exhibit biased evolution towards utilizing different carbon sources, yet all trajectories converge towards higher fitness gains. When lac+ (lactose-eater) and lac- (acetate-eater) were co-cultured in L medium, all lac- individuals were eventually eliminated, while lac + individuals were consistently selected and retained.

Conclusions: Our findings indicate that species tend to evolve with a bias towards directions that offer higher fitness gains, partly because high-fitness-gain directions competitively exclude low-fitness-gain directions.

Background: Evolutionary divergence and genetic variation are often linked to differences in microbial community structure and diversity. While environmental factors and diet heavily influence gut microbial communities, host species contributions are harder to quantify. Closely related species living in sympatry provide a unique opportunity to investigate species differences without the confounding effects of habitat and dietary variation. We therefore compared and contrasted the gut microbiota of three sympatric plover species: the widespread Kittlitz's and white-fronted plovers (Anarhynchus pecuarius and A. marginatus) and the endemic and vulnerable Madagascar plover (A. thoracicus).

Results: We found no significant differences in the beta diversity (composition) of the gut microbiota of the three species. However, A. thoracicus exhibited higher intraspecific compositional similarity (i.e. lower pairwise distances) than the other two species; this pattern was especially pronounced among juveniles. By contrast, microbial alpha diversity varied significantly among the species, being highest in A. pecuarius, intermediate in A. marginatus and lowest in A. thoracicus. This pattern was again stronger among juveniles. Geographical distance did not significantly affect the composition of the gut microbiota, but genetic relatedness did.

Conclusion: While patterns of microbial diversity varied across species, the lack of compositional differences suggests that habitat and diet likely exert a strong influence on the gut microbiota of plovers. This may be enhanced by their precocial, ground-dwelling nature, which could facilitate the horizontal transmission of microbes from the environment. We hypothesise that gut microbiota diversity in plovers primarily reflects the ecological pool of microbiota, which is subsequently modified by host-specific factors including genetics. The reduced microbial and genetic diversity of the endemic A. thoracicus may hinder its ability to adapt to environmental changes, highlighting the need for increased conservation efforts for this vulnerable species.

Background: The invasion of non-native species into ecosystems is a growing human-induced problem. To control their spread and population growth, knowledge is needed on the factors that facilitate or impede their invasions. In animals, traits often associated with invasion success are high activity, boldness, and aggression. However, these traits also make individuals susceptible to predation, which could curb population growth. We investigated if a recent invader into the Baltic Sea, the shrimp Palaemon elegans, differs in risk-taking from a native shrimp, P. adspersus. We recorded activity, habitat choice, and response to perceived predation threat of both species.

Results: We found the invading shrimp to take greater risks than the native one; while the native shrimp adjusted its behaviour to habitat structure and exposure to a perceived predator, the non-native shrimp did not, and it resumed normal activity sooner after a perceived predation threat. Despite the greater risk taking by the non-native shrimp, its population has grown rapidly during the last two decades in the investigated area and is now larger than that of the native shrimp.

Conclusions: We discuss plausible explanations for the population growth of the invader, including the recent decline in predatory fishes that could have reduced the cost of risk-taking, and anthropogenic eutrophication that has increased food abundance could have allowed the population growth. These results stress the need to assess the optimality of the behaviours of both native and non-native species when investigating the factors that influence invasion success in human-disturbed environments.

Background: We focus on Haldane's familial selection in monogamous families in a diploid population, where the survival probability of each sibling is determined by altruistic food sharing with its siblings during starvation. An autosomal recessive-dominant or intermediate allele pair uniquely determines the altruistic or selfish behavior, which are coded by homozygotes. We focus on the case when additive cost and benefit functions determine the survival probability of each full sibling.

Results: We provide conditions for the existence of the altruistic and selfish homozygote. We show that the condition of evolutionary stability of altruism depends on the genotype-phenotype mapping. Furthermore, if the offspring size increases then the condition of evolutionary stability of altruism becomes stricter. Contrary to that, for the evolutionary stability of selfish behavior it is enough if the classical Hamilton's rule does not hold. Moreover, when the classical Hamilton's rule holds and the condition of evolutionary stability of altruism does not hold, then the selfish and altruistic phenotypes coexist.

Conclusions: In summary, the classical Hamilton's rule is a sufficient condition for the existence of altruism, but it alone does not imply the evolutionary stability of the pure altruistic homozygote population when the altruistic siblings share the cost of altruism.