Proceedings of the Royal Society B最新文献_第7页

Interactive effects of foundation species on ecosystem functioning and stability in response to disturbance 基础物种对生态系统功能和稳定性的交互作用

Proceedings of the Royal Society B

Pub Date : 2019-10-16 DOI: 10.1098/rspb.2019.1857

Anita Narwani, M. Reyes, A. Pereira, Hannele Penson, Stuart R. Dennis, Sam Derrer, P. Spaak, B. Matthews

A major challenge in ecology is to understand determinants of ecosystem functioning and stability in the face of disturbance. Some important species can strongly shape community structure and ecosystem functioning, but their impacts and interactions on ecosystem-level responses to disturbance are less well known. Shallow ponds provide a model system in which to study the effects of such species because some taxa mitigate transitions between alternative ecosystem states caused by eutrophication. We performed pond experiments to test how two foundation species (a macrophyte and a mussel) affected the biomass of planktonic primary producers and its stability in response to nutrient additions. Individually, each species reduced phytoplankton biomass and tended to increase rates of recovery from disturbance, but together the species reversed these effects, particularly with larger nutrient additions. This reversal was mediated by high cyanobacterial dominance of the community and a resulting loss of trait evenness. Effects of the foundation species on primary producer biomass were associated with effects on other ecosystem properties, including turbidity and dissolved oxygen. Our work highlights the important role of foundation species and their interactive effects in determining responses of ecosystem functioning to disturbance.

生态学的一个主要挑战是了解生态系统在面对干扰时功能和稳定性的决定因素。一些重要的物种可以强烈地塑造群落结构和生态系统功能，但它们对生态系统水平对干扰的响应的影响和相互作用尚不清楚。浅池为研究这些物种的影响提供了一个模型系统，因为一些分类群减轻了由富营养化引起的不同生态系统状态之间的过渡。我们进行了池塘实验，以测试两种基础物种(一种大型植物和一种贻贝)如何影响浮游初级生产者的生物量及其对营养添加的稳定性。单独而言，每个物种都减少了浮游植物生物量，并倾向于增加从干扰中恢复的速度，但这些物种共同逆转了这些效应，特别是在增加大量营养物质的情况下。这种逆转是由社区的高蓝藻优势和由此导致的性状均匀性损失介导的。基础种对初级生产者生物量的影响与对其他生态系统特性的影响有关，包括浊度和溶解氧。我们的工作强调了基础物种及其相互作用在决定生态系统功能对干扰的响应中的重要作用。

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引用次数: 11

Differential female sociality is linked with the fine-scale structure of sexual interactions in replicate groups of red junglefowl, Gallus gallus 雌性社会性的差异与红丛林鸮复制群体的性互动的精细结构有关

Proceedings of the Royal Society B

Pub Date : 2019-10-16 DOI: 10.1098/rspb.2019.1734

Grant C. McDonald, Lewis G. Spurgin, Eleanor A. Fairfield, D. Richardson, T. Pizzari

Recent work indicates that social structure has extensive implications for patterns of sexual selection and sexual conflict. However, little is known about the individual variation in social behaviours linking social structure to sexual interactions. Here, we use network analysis of replicate polygynandrous groups of red junglefowl (Gallus gallus) to show that the association between social structure and sexual interactions is underpinned by differential female sociality. Sexual dynamics are largely explained by a core group of highly social, younger females, which are more fecund and more polyandrous, and thus associated with more intense postcopulatory competition for males. By contrast, less fecund females from older cohorts, which tend to be socially dominant, avoid male sexual attention by clustering together and perching on branches, and preferentially reproduce with dominant males by more exclusively associating and mating with them. Collectively, these results indicate that individual females occupy subtly different social niches and demonstrate that female sociality can be an important factor underpinning the landscape of intrasexual competition and the emergent structure of animal societies.

最近的研究表明，社会结构对性选择和性冲突的模式有着广泛的影响。然而，关于社会结构与性互动之间社会行为的个体差异，我们所知甚少。本文通过对重复一夫多妻制的红丛林鸮(Gallus Gallus)群体的网络分析表明，社会结构和性互动之间的联系是由雌性社会性差异所支撑的。性动态在很大程度上可以用一个高度社会化的年轻女性核心群体来解释，她们生育能力更强，一夫多妻制更强，因此与更激烈的交配后对男性的竞争有关。相比之下，来自较老群体的低生育能力的雌性往往在社会上处于优势地位，它们通过聚集在一起并栖息在树枝上来避免雄性的性关注，并通过更专一地与优势雄性交往和交配来优先与它们繁殖。总的来说，这些结果表明，雌性个体占据着微妙的不同社会生态位，并表明雌性社会性可能是支撑无性竞争景观和动物社会新兴结构的重要因素。

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引用次数: 15

Carotenoid pigmentation in salmon: variation in expression at BCO2-l locus controls a key fitness trait affecting red coloration 三文鱼的类胡萝卜素色素沉着:bco2 - 1基因座的表达变化控制着影响红色的关键适应度性状

Proceedings of the Royal Society B

Pub Date : 2019-10-16 DOI: 10.1098/rspb.2019.1588

S. Lehnert, S. Lehnert, K. Christensen, K. Christensen, W. Vandersteen, D. Sakhrani, T. Pitcher, J. Heath, B. Koop, D. Heath, R. Devlin

Carotenoids are primarily responsible for the characteristic red flesh coloration of salmon. Flesh coloration is an economically and evolutionarily significant trait that varies inter- and intra-specifically, yet the underlying genetic mechanism is unknown. Chinook salmon (Oncorhynchus tshawytscha) represents an ideal system to study carotenoid variation as, unlike other salmonids, they exhibit extreme differences in carotenoid utilization due to genetic polymorphisms. Here, we crossed populations of Chinook salmon with fixed differences in flesh coloration (red versus white) for a genome-wide association study to identify loci associated with pigmentation. Here, the beta-carotene oxygenase 2-like (BCO2-l) gene was significantly associated with flesh colour, with the most significant single nucleotide polymorphism explaining 66% of the variation in colour. BCO2 gene disruption is linked to carotenoid accumulation in other taxa, therefore we hypothesize that an ancestral mutation partially disrupting BCO2-l activity (i.e. hypomorphic mutation) allowed the deposition and accumulation of carotenoids within Salmonidae. Indeed, we found elevated transcript levels of BCO2-l in white Chinook salmon relative to red. The long-standing mystery of why salmon are red, while no other fishes are, is thus probably explained by a hypomorphic mutation in the proto-salmonid at the time of divergence of red-fleshed salmonid genera (approx. 30 Ma).

类胡萝卜素是三文鱼特有的红色果肉颜色的主要原因。肉色是一种经济上和进化上重要的性状，它在种间和种内都有变化，但其潜在的遗传机制尚不清楚。奇努克鲑鱼(Oncorhynchus tshawytscha)是研究类胡萝卜素变异的理想系统，因为与其他鲑鱼不同，它们由于遗传多态性而在类胡萝卜素利用方面表现出极大的差异。在这里，我们杂交了肉色(红色和白色)有固定差异的奇努克鲑鱼种群，进行全基因组关联研究，以确定与色素沉着相关的位点。在这里，β -胡萝卜素加氧酶2样(BCO2-l)基因与果肉颜色显著相关，最显著的单核苷酸多态性解释了66%的颜色变化。BCO2基因破坏与其他类群中的类胡萝卜素积累有关，因此我们假设祖先突变部分破坏BCO2- 1活性(即次形突变)允许类胡萝卜素在鲑鱼科中的沉积和积累。事实上，我们发现白色奇努克鲑鱼的bco2 - 1转录水平比红色的高。为什么鲑鱼是红色的，而其他鱼类却不是，这个长期存在的谜团可能是在红肉鲑属分化时，原始鲑属发生了次胚突变。30 Ma)。

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引用次数: 34

Habituation of mating preferences: a response to Chiandetti and Turatto 交配偏好的习惯化:对Chiandetti和Turatto的回应

Proceedings of the Royal Society B

Pub Date : 2019-10-16 DOI: 10.1098/rspb.2019.2103

M. J. Daniel, L. Koffinas, Kimberly A. Hughes

引用次数: 0

Evolutionary simulations of Z-linked suppression gene drives z连锁抑制基因驱动的进化模拟

Proceedings of the Royal Society B

Pub Date : 2019-10-09 DOI: 10.1098/rspb.2019.1070

L. Holman

Synthetic gene drives may soon be used to suppress or eliminate populations of disease vectors, pathogens, invasive species, and agricultural pests. Recent proposals have focused on using Z-linked gene drives to control species with ZW sex determination, which include Lepidopteran pests, parasitic trematodes, and cane toads. These proposals include Z-linked ‘W-shredders’, which would suppress populations by cleaving the W chromosome and causing females to produce only sons, as well as Z-linked female-sterilizing gene drives. Here, I use eco-evolutionary simulations to evaluate the potential of some proposed Z-linked gene drives, and to produce recommendations regarding their design and use. The simulations show that W-shredders are likely to be highly effective at eradicating populations provided that resistance to W-shredding cannot evolve. However, W-shredder alleles can invade populations from very low frequencies, making it difficult to eliminate specific populations while leaving nearby populations untouched; this issue may restrict their possible uses.

合成基因驱动可能很快就会被用于抑制或消除疾病载体、病原体、入侵物种和农业害虫的种群。最近的建议集中在使用z连锁基因驱动来控制具有ZW性别决定的物种，包括鳞翅目害虫、寄生吸虫和甘蔗蟾蜍。这些建议包括z连锁的“W粉碎机”，它将通过切割W染色体导致女性只生儿子来抑制种群数量，以及z连锁的女性不育基因驱动。在这里，我使用生态进化模拟来评估一些提议的z连锁基因驱动的潜力，并提出有关其设计和使用的建议。模拟表明，如果对w -粉碎机的抵抗力无法进化，那么w -粉碎机可能在消灭种群方面非常有效。然而，W-shredder等位基因可以从非常低的频率入侵种群，这使得很难消灭特定的种群，同时使附近的种群保持不变;这个问题可能会限制它们的使用。

引用次数: 11

Long-term persistence of structured habitats: seagrass meadows as enduring hotspots of biodiversity and faunal stability 结构栖息地的长期持续:海草草甸作为生物多样性和动物稳定性的持久热点

Proceedings of the Royal Society B

Pub Date : 2019-10-09 DOI: 10.1098/rspb.2019.1861

A. Hyman, T. Frazer, C. Jacoby, Jessica R. Frost, M. Kowalewski

Ecological studies indicate that structurally complex habitats support elevated biodiversity, stability and resilience. The long-term persistence of structured habitats and their importance in maintaining biodiverse hotspots remain underexplored. We combined geohistorical data (dead mollusc assemblages, ‘DA’) and contemporary surveys (live mollusc assemblages, ‘LA’) to assess the persistence of local seagrass habitats over multi-centennial timescales and to evaluate whether they acted as long-term drivers of biodiversity, stability and resilience of associated fauna. We sampled structured seagrass meadows and open sandy bottoms along Florida's Gulf Coast. Results indicated that: (i) LA composition differed significantly between the two habitat types, (ii) LA from seagrass sites were characterized by significantly elevated local biodiversity and significantly higher spatial stability, (iii) DA composition differed significantly between the two habitat types, and (iv) fidelity between LA and DA was significantly greater for seagrass habitats. Contemporary results support the hypotheses that local biodiversity and spatial stability of marine benthos are both elevated in structured seagrass habitats. Geohistorical results suggest that structured habitats persist as local hotspots of elevated biodiversity and faunal stability over centennial-to-millennial timescales; indicating that habitat degradation and concomitant loss within structurally complex marine systems is a key driver of declining biodiversity and resilience.

生态学研究表明，结构复杂的栖息地有助于提高生物多样性、稳定性和复原力。结构栖息地的长期持久性及其对维持生物多样性热点的重要性仍未得到充分探索。我们结合地理历史数据(死亡软体动物组合，“DA”)和当代调查(活软体动物组合，“LA”)来评估当地海草栖息地在数百年时间尺度上的持久性，并评估它们是否作为生物多样性、稳定性和相关动物群恢复力的长期驱动因素。我们在佛罗里达州墨西哥湾沿岸取样了结构海草草甸和开放的沙质底部。结果表明:(1)两种生境类型的LA组成存在显著差异;(2)海草样地的LA具有显著提高的局部生物多样性和更高的空间稳定性;(3)两种生境类型的DA组成存在显著差异;当前的研究结果支持这样的假设，即在结构海草栖息地中，海洋底栖动物的局部生物多样性和空间稳定性都得到了提高。地理历史研究结果表明，在百年至千年的时间尺度上，结构化栖息地仍然是生物多样性和动物稳定性提高的局部热点;表明在结构复杂的海洋系统中，栖息地退化和随之而来的丧失是生物多样性和复原力下降的关键驱动因素。

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引用次数: 24

The early elasmobranch Phoebodus: phylogenetic relationships, ecomorphology and a new time-scale for shark evolution. 早期鞘鳃亚目 Phoebodus：系统发育关系、形态学和鲨鱼进化的新时间尺度。

Proceedings of the Royal Society B

Pub Date : 2019-10-09 Epub Date: 2019-10-02 DOI: 10.1098/rspb.2019.1336

Linda Frey, Michael Coates, Michał Ginter, Vachik Hairapetian, Martin Rücklin, Iwan Jerjen, Christian Klug

Anatomical knowledge of early chondrichthyans and estimates of their phylogeny are improving, but many taxa are still known only from microremains. The nearly cosmopolitan and regionally abundant Devonian genus Phoebodus has long been known solely from isolated teeth and fin spines. Here, we report the first skeletal remains of Phoebodus from the Famennian (Late Devonian) of the Maïder region of Morocco, revealing an anguilliform body, specialized braincase, hyoid arch, elongate jaws and rostrum, complementing its characteristic dentition and ctenacanth fin spines preceding both dorsal fins. Several of these features corroborate a likely close relationship with the Carboniferous species Thrinacodus gracia, and phylogenetic analysis places both taxa securely as members of the elasmobranch stem lineage. Identified as such, phoebodont teeth provide a plausible marker for range extension of the elasmobranchs into the Middle Devonian, thus providing a new minimum date for the origin of the chondrichthyan crown-group. Among pre-Carboniferous jawed vertebrates, the anguilliform body shape of Phoebodus is unprecedented, and its specialized anatomy is, in several respects, most easily compared with the modern frilled shark Chlamydoselachus. These results add greatly to the morphological, and by implication ecological, disparity of the earliest elasmobranchs.

关于早期软骨鱼类的解剖学知识及其系统发育的估计正在不断改进，但许多类群仍然只能从微小残骸中了解。泥盆纪的Phoebodus属几乎是世界性的，在各地都有大量分布，长期以来人们仅从孤立的牙齿和鳍刺中了解到该属的情况。在这里，我们首次报告了来自摩洛哥 Maïder 地区法门期（晚泥盆世）的 Phoebodus 的骨骼遗骸，揭示了其雏形的身体、特化的脑壳、舌骨弓、长颚和喙，与其特征性的牙齿和两个背鳍前的栉状鳍刺相得益彰。这些特征证实了它可能与石炭纪物种 Thrinacodus gracia 关系密切，而系统发育分析则将这两个类群确定为鞘鳃亚纲干系的成员。通过系统发育分析，这两个类群被确定为伶鼻鳃亚纲干系的成员。伶鼻鳃亚纲牙齿被确定为伶鼻鳃亚纲干系的成员，为伶鼻鳃亚纲的分布范围扩展到中泥盆世提供了一个可信的标记，从而为软骨鱼类冠群的起源提供了一个新的最低日期。在石炭纪以前的有颌脊椎动物中，Phoebodus的guilliform体形是史无前例的，其特殊的解剖学在几个方面最容易与现代的褶鲨Chlamydoselachus相比较。这些结果大大增加了最早的鞘鳃类动物在形态学上的差异，同时也意味着生态学上的差异。

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引用次数: 0

Microbes and macro-invertebrates show parallel β-diversity but contrasting α-diversity patterns in a marine natural experiment 在海洋自然实验中，微生物和大型无脊椎动物表现出平行的β-多样性和相反的α-多样性模式

Proceedings of the Royal Society B

Pub Date : 2019-10-09 DOI: 10.1098/rspb.2019.0999

G. Rapacciuolo, G. Rapacciuolo, J. Beman, L. M. Schiebelhut, M. Dawson

Documenting ecological patterns across spatially, temporally and taxonomically diverse ecological communities is necessary for a general understanding of the processes shaping biodiversity. A major gap in our understanding remains the comparison of diversity patterns across a broad spectrum of evolutionarily and functionally diverse organisms, particularly in the marine realm. Here, we aim to narrow this gap by comparing the diversity patterns of free-living microbes and macro-invertebrates across a natural experiment provided by the marine lakes of Palau: geographically discrete and environmentally heterogeneous bodies of seawater with comparable geological and climatic history, and a similar regional species pool. We find contrasting patterns of α-diversity but remarkably similar patterns of β-diversity between microbial and macro-invertebrate communities among lakes. Pairwise dissimilarities in community composition among lakes are positively correlated between microbes and macro-invertebrates, and influenced to a similar degree by marked gradients in oxygen concentration and salinity. Our findings indicate that a shared spatio-temporal and environmental context may result in parallel patterns of β-diversity in microbes and macro-invertebrates, in spite of key trait differences between these organisms. This raises the possibility that parallel processes also influence transitions among regional biota across the tree of life, at least in the marine realm.

在空间、时间和分类上多样化的生态群落中记录生态模式是了解生物多样性形成过程的必要条件。我们在理解上的一个主要差距仍然是对广泛的进化和功能多样化生物的多样性模式进行比较，特别是在海洋领域。在这里，我们的目标是通过比较帕劳海洋湖泊提供的自然实验中自由生活的微生物和大型无脊椎动物的多样性模式来缩小这一差距:地理上分散，环境上不均匀的海水体，具有可比的地质和气候历史，以及类似的区域物种池。结果表明，湖泊微生物群落与大型无脊椎动物群落α-多样性存在明显差异，而β-多样性具有显著的相似性。湖泊群落组成的两两差异在微生物和大型无脊椎动物之间呈正相关，并受氧浓度和盐度显著梯度的影响程度相似。我们的研究结果表明，尽管微生物和大型无脊椎动物之间存在关键性状差异，但共享的时空和环境背景可能导致微生物和大型无脊椎动物β-多样性的平行模式。这就提出了一种可能性，即平行过程也会影响整个生命树的区域生物群之间的过渡，至少在海洋领域是这样。

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引用次数: 9

Cilia drive developmental plasticity and are essential for efficient prey detection in predatory nematodes. 纤毛是发育可塑性的驱动力，也是捕食线虫有效探测猎物的关键。

Proceedings of the Royal Society B

Pub Date : 2019-10-09 Epub Date: 2019-10-02 DOI: 10.1098/rspb.2019.1089

Eduardo Moreno, James W Lightfoot, Maša Lenuzzi, Ralf J Sommer

Cilia are complex organelles involved in a broad array of functions in eukaryotic organisms. Nematodes employ cilia for environmental sensing, which shapes developmental decisions and influences morphologically plastic traits and adaptive behaviours. Here, we assess the role of cilia in the nematode Pristionchus pacificus, and determine their importance in regulating the developmentally plastic mouth-form decision in addition to predatory feeding and self-recognition behaviours, all of which are not present in Caenorhabditis elegans. An analysis of a multitude of cilia-related mutants including representatives of the six protein subcomplexes required in intraflagellar transport (IFT) plus the regulatory factor X transcription factor daf-19 revealed that cilia are essential for processing the external cues influencing the mouth-form decision and for the efficient detection of prey. Surprisingly, we observed that loss-of-function mutations in the different IFT components resulted in contrasting mouth-form phenotypes and different degrees of predation deficiencies. This observation supports the idea that perturbing different IFT subcomplexes has different effects on signalling downstream of the cilium. Finally, self-recognition was maintained in the cilia deficient mutants tested, indicating that the mechanisms triggering self-recognition in P. pacificus may not require the presence of fully functional cilia.

纤毛是一种复杂的细胞器，在真核生物体内发挥着广泛的功能。线虫利用纤毛感知环境，从而做出发育决定并影响形态可塑性特征和适应行为。在这里，我们评估了纤毛在太平洋栉水母线虫（Pristionchus pacificus）中的作用，并确定了纤毛在调节具有发育可塑性的口形决定以及捕食和自我识别行为方面的重要性，所有这些行为在草履虫中都不存在。我们分析了大量与纤毛相关的突变体，其中包括鞘内运输（IFT）所需的六种蛋白质亚复合体的代表以及调节因子 X 转录因子 daf-19，结果发现，纤毛对于处理影响口型决定的外部线索以及有效探测猎物至关重要。令人惊讶的是，我们观察到 IFT 不同组分的功能缺失突变会导致截然不同的口型表型和不同程度的捕食缺陷。这一观察结果支持了这样一种观点，即干扰不同的 IFT 亚复合物会对纤毛下游的信号传导产生不同的影响。最后，在测试的纤毛缺失突变体中，自我识别能力得以维持，这表明引发太平洋豚鼠自我识别的机制可能并不需要存在功能完备的纤毛。

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引用次数: 0

Head to head: the case for fighting behaviour in Megaloceros giganteus using finite-element analysis 头对头:巨型巨角鲸的打斗行为使用有限元分析

Proceedings of the Royal Society B

Pub Date : 2019-10-09 DOI: 10.1098/rspb.2019.1873

Ada J. Klinkhamer, N. Woodley, J. M. Neenan, W. Parr, P. Clausen, M. Sánchez-Villagra, G. Sansalone, A. Lister, S. Wroe

The largest antlers of any known deer species belonged to the extinct giant deer Megaloceros giganteus. It has been argued that their antlers were too large for use in fighting, instead being used only in ritualized displays to attract mates. Here, we used finite-element analysis to test whether the antlers of M. giganteus could have withstood forces generated during fighting. We compared the mechanical performance of antlers in M. giganteus with three extant deer species: red deer (Cervus elaphus), fallow deer (Dama dama) and elk (Alces alces). Von Mises stress results suggest that M. giganteus was capable of withstanding some fighting loads, provided that their antlers interlocked proximally, and that their antlers were best adapted for withstanding loads from twisting rather than pushing actions, as are other deer with palmate antlers. We conclude that fighting in M. giganteus was probably more constrained and predictable than in extant deer.

已知鹿种中最大的鹿角属于已经灭绝的巨型鹿Megaloceros giganteus。有人认为，它们的角太大，无法用于战斗，而只是在仪式化的展示中用来吸引配偶。在这里，我们使用有限元分析来测试M. giganteus的鹿角是否能够承受战斗中产生的力量。将巨鹿角的力学性能与马鹿(Cervus elaphus)、马鹿(Dama Dama)和麋鹿(Alces Alces)三种现存鹿种进行了比较。冯·米塞斯的应力结果表明，巨鹿能够承受一些战斗负荷，只要它们的鹿角在近端互锁，它们的鹿角最适合承受扭转而不是推动的负荷，就像其他有掌状鹿角的鹿一样。我们的结论是，与现存的鹿相比，巨鹿的战斗可能更受约束，也更容易预测。

引用次数: 7