scholarly journals Ecological speciation in dynamic landscapes

2011 ◽  
Vol 24 (12) ◽  
pp. 2663-2677 ◽  
Author(s):  
R. AGUILÉE ◽  
A. LAMBERT ◽  
D. CLAESSEN
Keyword(s):  
Ecological Speciation ◽  
Dynamic Landscapes

Extinction Thresholds and Metapopulation Persistence in Dynamic Landscapes

2000 ◽  
Vol 156 (5) ◽  
pp. 478
Author(s):  
Keymer ◽  
Marquet ◽  
Velasco-Hernández ◽  
Levin
Keyword(s):  
Dynamic Landscapes ◽  
Metapopulation Persistence

scholarly journals Laboratory and microcosm experiments reveal contrasted adaptive responses to ammonia and water mineralisation in aquatic stages of the sibling species Anopheles gambiae (sensu stricto) and Anopheles coluzzii

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nwamaka Oluchukwu Akpodiete ◽  
Frédéric Tripet
Keyword(s):  
West Africa ◽  
Anopheles Gambiae ◽  
Emerging Adults ◽  
Sibling Species ◽  
Adult Emergence ◽  
Ecological Speciation ◽  
Sensu Stricto ◽  
Rice Fields ◽  
Anopheles Coluzzii ◽  
Phenotypic Quality

Abstract Background The sibling species of the malaria mosquito, Anopheles gambiae (sensu stricto) and Anopheles coluzzii co-exist in many parts of West Africa and are thought to have recently diverged through a process of ecological speciation with gene flow. Divergent larval ecological adaptations, resulting in Genotype-by-Environment (G × E) interactions, have been proposed as important drivers of speciation in these species. In West Africa, An. coluzzii tends to be associated with permanent man-made larval habitats such as irrigated rice fields, which are typically more eutrophic and mineral and ammonia-rich than the temporary rain pools exploited by An. gambiae (s.s.) Methods To highlight G × E interactions at the larval stage and their possible role in ecological speciation of these species, we first investigated the effect of exposure to ammonium hydroxide and water mineralisation on larval developmental success. Mosquito larvae were exposed to two water sources and increasing ammonia concentrations in small containers until adult emergence. In a second experiment, larval developmental success was compared across two contrasted microcosms to highlight G × E interactions under conditions such as those found in the natural environment. Results The first experiment revealed significant G × E interactions in developmental success and phenotypic quality for both species in response to increasing ammonia concentrations and water mineralisation. The An. coluzzii strain outperformed the An. gambiae (s.s.) strain under limited conditions that were closer to more eutrophic habitats. The second experiment revealed divergent crisscrossing reaction norms in the developmental success of the sibling species in the two contrasted larval environments. As expected, An. coluzzii had higher emergence rates in the rice paddy environment with emerging adults of superior phenotypic quality compared to An. gambiae (s.s.), and vice versa, in the rain puddle environment. Conclusions Evidence for such G × E interactions lends support to the hypothesis that divergent larval adaptations to the environmental conditions found in man-made habitats such as rice fields in An. coluzzii may have been an important driver of its ecological speciation.

scholarly journals The draft genome of the specialist flea beetle Altica viridicyanea (Coleoptera: Chrysomelidae)

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Huai-Jun Xue ◽  
Yi-Wei Niu ◽  
Kari A. Segraves ◽  
Rui-E Nie ◽  
Ya-Jing Hao ◽  
...  
Keyword(s):  
Host Plant ◽  
Plant Cell Wall ◽  
Flea Beetle ◽  
Repetitive Sequences ◽  
Draft Genome ◽  
Gene Families ◽  
Ecological Speciation ◽  
Secondary Chemistry ◽  
Host Plant Specialization ◽  
Insight Into

Abstract Background Altica (Coleoptera: Chrysomelidae) is a highly diverse and taxonomically challenging flea beetle genus that has been used to address questions related to host plant specialization, reproductive isolation, and ecological speciation. To further evolutionary studies in this interesting group, here we present a draft genome of a representative specialist, Altica viridicyanea, the first Alticinae genome reported thus far. Results The genome is 864.8 Mb and consists of 4490 scaffolds with a N50 size of 557 kb, which covered 98.6% complete and 0.4% partial insect Benchmarking Universal Single-Copy Orthologs. Repetitive sequences accounted for 62.9% of the assembly, and a total of 17,730 protein-coding gene models and 2462 non-coding RNA models were predicted. To provide insight into host plant specialization of this monophagous species, we examined the key gene families involved in chemosensation, detoxification of plant secondary chemistry, and plant cell wall-degradation. Conclusions The genome assembled in this work provides an important resource for further studies on host plant adaptation and functionally affiliated genes. Moreover, this work also opens the way for comparative genomics studies among closely related Altica species, which may provide insight into the molecular evolutionary processes that occur during ecological speciation.

scholarly journals Population genetic structure of a major reef-building coral species Acropora downingi in northeastern Arabian Peninsula

Coral Reefs ◽  
2021 ◽  
Author(s):  
Felipe Torquato ◽  
Jessica Bouwmeester ◽  
Pedro Range ◽  
Alyssa Marshell ◽  
Mark A. Priest ◽  
...  
Keyword(s):  
Population Structure ◽  
Genetic Study ◽  
Persian Gulf ◽  
Population Genetic ◽  
Coral Species ◽  
Arabian Peninsula ◽  
Ecological Speciation ◽  
Population Genetic Study ◽  
Sea Of Oman ◽  
Neutral Markers

AbstractCurrent seawater temperatures around the northeastern Arabian Peninsula resemble future global forecasts as temperatures > 35 °C are commonly observed in summer. To provide a more fundamental aim of understanding the structure of wild populations in extreme environmental conditions, we conducted a population genetic study of a widespread, regional endemic table coral species, Acropora downingi, across the northeastern Arabian Peninsula. A total of 63 samples were collected in the southern Arabian/Persian Gulf (Abu Dhabi and Qatar) and the Sea of Oman (northeastern Oman). Using RAD-seq techniques, we described the population structure of A. downingi across the study area. Pairwise G’st and distance-based analyses using neutral markers displayed two distinct genetic clusters: one represented by Arabian/Persian Gulf individuals, and the other by Sea of Oman individuals. Nevertheless, a model-based method applied to the genetic data suggested a panmictic population encompassing both seas. Hypotheses to explain the distinctiveness of phylogeographic subregions in the northeastern Arabian Peninsula rely on either (1) bottleneck events due to successive mass coral bleaching, (2) recent founder effect, (3) ecological speciation due to the large spatial gradients in physical conditions, or (4) the combination of seascape features, ocean circulation and larval traits. Neutral markers indicated a slightly structured population of A. downingi, which exclude the ecological speciation hypothesis. Future studies across a broader range of organisms are required to furnish evidence for existing hypotheses explaining a population structure observed in the study area. Though this is the most thermally tolerant acroporid species worldwide, A. downingi corals in the Arabian/Persian Gulf have undergone major mortality events over the past three decades. Therefore, the present genetic study has important implications for understanding patterns and processes of differentiation in this group, whose populations may be pushed to extinction as the Arabian/Persian Gulf warms.

scholarly journals Integrated genomic analysis reveals regulatory pathways and dynamic landscapes of the tRNA transcriptome

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zefang Sun ◽  
Jia Tan ◽  
Minqiong Zhao ◽  
Qiyao Peng ◽  
Mingqing Zhou ◽  
...  
Keyword(s):  
Expression Profiles ◽  
Genomic Analysis ◽  
Rna Seq ◽  
Regulatory Pathways ◽  
Cellular Processes ◽  
Dynamic Landscapes ◽  
Rna Fragments ◽  
A Cell ◽  
Considerable Impact ◽  
New Algorithms

AbstracttRNAs and tRNA-derived RNA fragments (tRFs) play various roles in many cellular processes outside of protein synthesis. However, comprehensive investigations of tRNA/tRF regulation are rare. In this study, we used new algorithms to extensively analyze the publicly available data from 1332 ChIP-Seq and 42 small-RNA-Seq experiments in human cell lines and tissues to investigate the transcriptional and posttranscriptional regulatory mechanisms of tRNAs. We found that histone acetylation, cAMP, and pluripotency pathways play important roles in the regulation of the tRNA gene transcription in a cell-specific manner. Analysis of RNA-Seq data identified 950 high-confidence tRFs, and the results suggested that tRNA pools are dramatically distinct across the samples in terms of expression profiles and tRF composition. The mismatch analysis identified new potential modification sites and specific modification patterns in tRNA families. The results also show that RNA library preparation technologies have a considerable impact on tRNA profiling and need to be optimized in the future.

scholarly journals Assessing the Impact of Urban Expansion on Surrounding Forested Landscape Connectivity across Space and Time

Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 359
Author(s):  
Zhouqiao Ren ◽  
Jianhua He ◽  
Qiaobing Yue
Keyword(s):  
Landscape Connectivity ◽  
Urban Expansion ◽  
Landscape Fragmentation ◽  
Sustainable Urban Development ◽  
Delayed Response ◽  
Conservation Practices ◽  
Rapid Urbanization ◽  
Dynamic Landscapes ◽  
The Impact ◽  
Over Time

Landscape connectivity is important for all organisms as it directly affects population dynamics. Yet, rapid urbanization has caused serious landscape fragmentation, which is the primary contributor of species extinctions worldwide. Previous studies have mostly used spatial snap-shots to evaluate the impact of urban expansion on landscape connectivity. However, the interactions among habitats over time in dynamic landscapes have been largely ignored. Here, we demonstrated that overlooking temporal connectivity can lead to the overestimation of the impact of urban expansion. How much greater the overestimation is depends on the amount of net habitat loss. Moreover, we showed that landscape connectivity may have a delayed response to urban expansion. Our analysis shifts the way to understand the ecological consequences of urban expansion. Our framework can guide sustainable urban development and can be inspiring to conservation practices under other contexts (e.g., climate change).

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