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Jizhong Zhou - One of the best experts on this subject based on the ideXlab platform.
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a Latitudinal Gradient of microbial β diversity in continental paddy soils
Global Ecology and Biogeography, 2021Co-Authors: Xian Xiao, Jizhong Zhou, Na Zhang, Yunfeng Yang, Bo Sun, Yuting LiangAbstract:Aim The β‐diversity of plants and animals generally decreases with increasing latitudes. Here, we tested whether this relationship also holds for soil microbes at both functional and taxonomic levels. Location China. Time period Between June and October 2013. Major taxa studied Soil archaea, bacteria, and functional genes. Methods We used a spatially explicit ‘L‐shaped’ sampling strategy in 39 paddy fields in China to study the pattern of soil microbial β‐diversity (i.e., species turnover, βz) across a Latitudinal Gradient (19.75° N to 47.58° N), with 11 soil samples taken within a 100 m × 100 m plot from each field. Archaeal and bacterial communities were analysed by sequencing 16S ribosomal RNA gene amplicons using Illumina MiSeq; microbial functional genes involved in C/N/P/S cycling were detected by GeoChip. Results We showed that the microbial β‐diversity varied considerably across taxonomic and functional groups. For both soil microbial communities and functional genes, β‐diversity decreased significantly along elevated latitudes at the continental scale. Woesearchaeota of archaeal communities, Bacteroidetes of bacterial communities, and the functional genes involved in methane production displayed the greatest decreases. Both mean temperature during the growing season of rice plants and paddy soil heterogeneity contributed to the Latitudinal patterns. Further analyses indicated that temperature was more important than soil heterogeneity in driving the β‐diversity of microbial communities and functional genes. Main conclusions These results highlight the importance of temperature‐driven soil microbial β‐diversity and suggest the potential to predict the changes of microbial diversity with climate change.
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taxonomic decomposition of the Latitudinal Gradient in species diversity of north american floras
Journal of Biogeography, 2018Co-Authors: Michael D Weiser, Jizhong Zhou, Nathan G Swenson, Brian J Enquist, Sean T Michaletz, Robert B WaideAbstract:Author(s): Weiser, MD; Swenson, NG; Enquist, BJ; Michaletz, S; Waide, RB; Zhou, J; Kaspari, M | Abstract: Aim: To test the Latitudinal Gradient in plant species diversity for self-similarity across taxonomic scales and amongst taxa. Location: North America. Methods: We used species richness data from 245 local vascular plant floras to quantify the slope and shape of the Latitudinal Gradients in species diversity (LGSD) across all plant species as well as within each family and order. We calculated the contribution of each family and order to the empirical LGSD. Results: We observed the canonical LGSD when all plants were considered with floras at the lowest latitudes having, on average, 451 more species than floras at the highest latitudes. When considering slope alone, most orders and families showed the expected negative slope, but 31.7% of families and 27.7% of orders showed either no significant relationship between latitude and diversity or a reverse LGSD. Latitudinal patterns of family diversity account for at least 14% of this LGSD. Most orders and families did not show the negative slope and concave-down quadratic shape expected by the pattern for all plant species. A majority of families did not make a significant contribution in species to the LGSD with 53% of plant families contributing little to nothing to the overall Gradient. Ten families accounted for more than 70% of the Gradient. Two families, the Asteraceae and Fabaceae, contributed a third of the LGSD. Main Conclusions: The empirical LGSD we describe here is a consequence of a Gradient in the number of families and diversification within relative few plant families. Macroecological studies typically aim to generate models that are general across taxa with the implicit assumption that the models are general within taxa. Our results strongly suggest that models of the Latitudinal Gradient in plant species richness that rely on environmental covariates (e.g. temperature, energy) are likely not general across plant taxa.
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soil bacterial endemism and potential functional redundancy in natural broadleaf forest along a Latitudinal Gradient
Scientific Reports, 2016Co-Authors: Yuguang Zhang, Jing Cong, Hui Lu, Ye Deng, Jizhong Zhou, Diqiang LiAbstract:Microorganisms play key roles in ecosystem processes and biogeochemical cycling, however, the relationship between soil microbial taxa diversity and their function in natural ecosystems is largely unknown. To determine how soil bacteria community and function are linked from the local to regional scale, we studied soil bacteria community composition, potential function and environmental conditions in natural and mature broadleaf forests along a Latitudinal Gradient in China, using the Illumina 16S rRNA sequencing and GeoChip technologies. The results showed strong biogeographic endemism pattern in soil bacteria were existed, and the spatial distance and climatic variables were the key controlling factors for this pattern. Therefore, dispersal limitation and environmental selection may represent two key processes in generating and maintaining the soil bacterial biogeographic pattern. By contrast, the soil bacterial potential function is highly convergent along the Latitudinal Gradient and there were highly differing bacterial community compositions, and the soil chemistry may include the main factors active in shaping the soil bacterial potential function. Therefore, the soil bacterial potential function may be affected by local Gradients in resource availability, and predicting soil bacterial potential function requires knowledge of abiotic and biotic environmental factors.
Wendy A Valenciamontoya - One of the best experts on this subject based on the ideXlab platform.
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rapid divergent evolution of an annual plant across a Latitudinal Gradient revealed by seed resurrection
Evolution, 2021Co-Authors: Wendy A Valenciamontoya, Elodie Flaven, Juliette Pouzadoux, Eric Imbert, Pierreolivier CheptouAbstract:Global change is expected to drive short-term evolution of natural populations. However, it remains unclear whether different populations are changing in unison. Here, we study contemporary evolution of growth-related and reproductive traits of three populations of Cyanus segetum face to warming and pollinator decline across a Latitudinal Gradient in France. We resurrected stored seeds sampled up to 24 years apart from northern, central-western, and southern populations and conducted an in situ common-garden experiment. To disentangle neutral from selection-driven differentiation, we calculated neutral genetic differentiation (FST ) and quantitative trait differentiation (QST ) between temporal samples. We found that phenotypic evolution was divergent across populations exhibiting different trends for rosette size, date of flowering, and capitula size. By measuring seed set as a proxy of fitness, we showed that samples with larger mean capitula size outperformed samples with smaller mean capitula size in the western and southern populations. Regression of traits on seed set showed that flowering date and capitula size are the primary determinants of fitness, and QST -FST comparisons indicated that natural selection has likely contributed to the shifts in flowering phenology and rosette size. These findings outline the potential for rescue of natural populations through contemporary evolution and emphasize the complex interplay between spatial and temporal variation in species' responses to global change.
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rapid divergent evolution of an annual plant across a Latitudinal Gradient revealed by seed resurrection
Evolution, 2021Co-Authors: Wendy A Valenciamontoya, Elodie Flaven, Juliette Pouzadoux, Eric Imbert, Pierreolivier CheptouAbstract:Global change is expected to drive short-term evolution of natural populations. However, it remains unclear whether different populations are changing in unison. Here, we study contemporary evolution of growth-related and reproductive traits of three populations of Cyanus segetum facing warming and pollinator decline across a Latitudinal Gradient in France. We resurrected stored seeds sampled up to 24 years apart from northern, central-western, and southern populations and conducted an in situ common-garden experiment. To disentangle neutral from selection-driven differentiation, we calculated neutral genetic differentiation (FST ) and quantitative trait differentiation (QST ) between temporal samples. We found that phenotypic evolution was divergent across populations exhibiting different trends for rosette size, date of flowering, and capitula size. By measuring seed set as a proxy of fitness, we showed that samples with larger mean capitula size outperformed samples with smaller mean capitula size in the western and southern populations. Regression of traits on seed set showed that flowering date and capitula size are the primary determinants of fitness, and QST -FST comparisons indicated that natural selection has likely contributed to the shifts in flowering phenology and rosette size. These findings outline the potential for rescue of natural populations through contemporary evolution and emphasize the complex interplay between spatial and temporal variation in species' responses to global change.
Anssi Laurila - One of the best experts on this subject based on the ideXlab platform.
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Antimicrobial peptide and sequence variation along a Latitudinal Gradient in two anurans
BMC Genetics, 2020Co-Authors: Maria Cortázar-chinarro, Anssi Laurila, Yvonne Meyer-lucht, Tom Van Der Valk, Alex Richter-boix, Jacob HoglundAbstract:Background While there is evidence of both purifying and balancing selection in immune defense genes, large-scale genetic diversity in antimicrobial peptides (AMPs), an important part of the innate immune system released from dermal glands in the skin, has remained uninvestigated. Here we describe genetic diversity at three AMP loci (Temporin, Brevinin and Palustrin) in two ranid frogs ( Rana arvalis and R. temporaria ) along a 2000 km Latitudinal Gradient. We amplified and sequenced part of the Acidic Propiece domain and the hypervariable Mature Peptide domain (~ 150-200 bp) in the three genes using Illumina Miseq and expected to find decreased AMP genetic variation towards the northern distribution limit of the species similarly to studies on MHC genetic patterns. Results We found multiple loci for each AMP and relatively high gene diversity, but no clear pattern of geographic genetic structure along the Latitudinal Gradient. We found evidence of trans-specific polymorphism in the two species, indicating a common evolutionary origin of the alleles. Temporin and Brevinin did not form monophyletic clades suggesting that they belong to the same gene family. By implementing codon evolution models we found evidence of strong positive selection acting on the Mature Peptide. We also found evidence of diversifying selection as indicated by divergent allele frequencies among populations and high Theta k values. Conclusion Our results suggest that AMPs are an important source of adaptive diversity, minimizing the chance of microorganisms developing resistance to individual peptides.
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allen s rule revisited quantitative genetics of extremity length in the common frog along a Latitudinal Gradient
Journal of Evolutionary Biology, 2011Co-Authors: Jussi Alho, Anssi Laurila, Ane T Laugen, Gábor Herczeg, Katja Rasanen, Juha MeriläAbstract:Ecogeographical rules linking climate to morphology have gained renewed interest because of climate change. Yet few studies have evaluated to what extent geographical trends ascribed to these rules have a genetic, rather than environmentally determined, basis. This applies especially to Allen's rule, which states that the relative extremity length decreases with increasing latitude. We studied leg length in the common frog (Rana temporaria) along a 1500 km Latitudinal Gradient utilizing wild and common garden data. In the wild, the body size-corrected femur and tibia lengths did not conform to Allen's rule but peaked at mid-latitudes. However, the ratio of femur to tibia length increased in the north, and the common garden data revealed a genetic cline consistent with Allen's rule in some trait and treatment combinations. While selection may have shortened the leg length in the north, the genetic trend seems to be partially masked by environmental effects.
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Increasing melanism along a Latitudinal Gradient in a widespread amphibian: local adaptation, ontogenic or environmental plasticity?
BMC evolutionary biology, 2010Co-Authors: Fredrik Söderman, Anssi Laurila, K. Ingemar JönssonAbstract:Background The thermal benefits of melanism in ectothermic animals are widely recognized, but relatively little is known about population differentiation in the degree of melanism along thermal Gradients, and the relative contributions of genetic vs. environmental components into the level of melanism expressed. We investigated variation in the degree of melanism in the common frog (Rana temporaria; an active heliotherm thermoregulator) by comparing the degree of melanism (i) among twelve populations spanning over 1500 km long Latitudinal Gradient across the Scandinavian Peninsula and (ii) between two populations from Latitudinal extremes subjected to larval temperature treatments in a common garden experiment.
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antipredator defenses along a Latitudinal Gradient in rana temporaria
Ecology, 2008Co-Authors: Anssi Laurila, Beatrice Lindgren, Ane T LaugenAbstract:Antipredator defenses are expected to decrease toward higher latitudes because predation rates are predicted to decrease with latitude. However, Latitudinal variation in predator avoidance and defense mechanisms has seldom been studied. We studied tadpole antipredator defenses in seven Rana temporaria populations collected along a 1500-km Latitudinal Gradient across Sweden, along which previous studies have found increasing tadpole growth and development rates. In a laboratory common garden experiment, we measured behavioral and morphological defenses by raising tadpoles in the presence and absence of a predator (Aeshna dragonfly larva) in two temperature treatments. We also estimated tadpole survival in the presence of free-ranging predators and compared predator densities between R. temporaria breeding ponds situated at low and high latitudes. Activity and foraging were generally positively correlated with latitude in the common garden experiment. While all populations responded to predator presence by decreasing activity and foraging, high-latitude populations maintained higher activity levels in the presence of the predator. All populations exhibited defensive morphology in body and tail shape. However, whereas tail depth tended to increase with latitude in the presence of predator, it did not change with latitude in the absence of the predator. Predator presence generally increased larval period and decreased growth rate. In the southern populations, predator presence tended to have a negative effect on metamorphic size, whereas in the northern populations predators had little or a positive effect on size. Latitude of origin had a strong effect on survival in the presence of a free-ranging predator, with high-latitude tadpoles experiencing higher mortality than those from the low latitudes. In the wild, predator densities were significantly lower in high-latitude than in mid- latitude breeding ponds. Although the higher activity level in the northern populations seems to confer a significant survival disadvantage under predation risk, it is probably needed to maintain the high growth and development rates. However, the occurrence of R. temporaria at high latitudes may be facilitated by the lower predator densities in the north.
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effects of ultraviolet b radiation on common frog rana temporaria embryos from along a Latitudinal Gradient
Oecologia, 2002Co-Authors: Maarit Pahkala, Anssi Laurila, Juha MeriläAbstract:Interspecific variation in ultraviolet-B (UV-B) radiation tolerance in amphibians is well established, but little is known about the possible intraspecific variation in UV-B radiation tolerance within any species. We studied the effects of UV-B radiation on common frog Rana temporaria embryos originating from eight populations spanning a 1,200 km Latitudinal Gradient across Sweden. Newly fertilised eggs were exposed to three different UV-B treatments [absent (no UV-B), normal (1.254 kJ m–2) and enhanced (1.584 kJ m–2, 26% above normal) levels] in a laboratory, and effects on survival, frequency of developmental anomalies, developmental rate and hatchling size were documented. UV-B radiation treatments did not have main factor effects on embryonic mortality or frequency of developmental anomalies. Survival to hatching was lower at higher latitudes, but it was independent of UV-B treatments. High UV-B treatment prolonged development time in five populations, whereas in one population development time was longest in the absence of UV-B. Even though the northernmost populations had the shortest development times, the interaction between latitude and development time was not significant. There was a significant population×UV-B interaction in hatchling size, indicating that hatchling size was negatively affected by the UV-B treatments in some of the populations. Hatchling size increased until mid-latitudes and was again somewhat smaller at the northernmost latitudes, but this was independent of UV-B treatments. These results suggest that although R. temporaria embryos are rather tolerant of UV-B radiation, and there is no clear Latitudinal pattern to UV-B tolerance in this species, the sublethal effects of UV-B on embryonic development may differ among different populations.
Pierreolivier Cheptou - One of the best experts on this subject based on the ideXlab platform.
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rapid divergent evolution of an annual plant across a Latitudinal Gradient revealed by seed resurrection
Evolution, 2021Co-Authors: Wendy A Valenciamontoya, Elodie Flaven, Juliette Pouzadoux, Eric Imbert, Pierreolivier CheptouAbstract:Global change is expected to drive short-term evolution of natural populations. However, it remains unclear whether different populations are changing in unison. Here, we study contemporary evolution of growth-related and reproductive traits of three populations of Cyanus segetum face to warming and pollinator decline across a Latitudinal Gradient in France. We resurrected stored seeds sampled up to 24 years apart from northern, central-western, and southern populations and conducted an in situ common-garden experiment. To disentangle neutral from selection-driven differentiation, we calculated neutral genetic differentiation (FST ) and quantitative trait differentiation (QST ) between temporal samples. We found that phenotypic evolution was divergent across populations exhibiting different trends for rosette size, date of flowering, and capitula size. By measuring seed set as a proxy of fitness, we showed that samples with larger mean capitula size outperformed samples with smaller mean capitula size in the western and southern populations. Regression of traits on seed set showed that flowering date and capitula size are the primary determinants of fitness, and QST -FST comparisons indicated that natural selection has likely contributed to the shifts in flowering phenology and rosette size. These findings outline the potential for rescue of natural populations through contemporary evolution and emphasize the complex interplay between spatial and temporal variation in species' responses to global change.
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rapid divergent evolution of an annual plant across a Latitudinal Gradient revealed by seed resurrection
Evolution, 2021Co-Authors: Wendy A Valenciamontoya, Elodie Flaven, Juliette Pouzadoux, Eric Imbert, Pierreolivier CheptouAbstract:Global change is expected to drive short-term evolution of natural populations. However, it remains unclear whether different populations are changing in unison. Here, we study contemporary evolution of growth-related and reproductive traits of three populations of Cyanus segetum facing warming and pollinator decline across a Latitudinal Gradient in France. We resurrected stored seeds sampled up to 24 years apart from northern, central-western, and southern populations and conducted an in situ common-garden experiment. To disentangle neutral from selection-driven differentiation, we calculated neutral genetic differentiation (FST ) and quantitative trait differentiation (QST ) between temporal samples. We found that phenotypic evolution was divergent across populations exhibiting different trends for rosette size, date of flowering, and capitula size. By measuring seed set as a proxy of fitness, we showed that samples with larger mean capitula size outperformed samples with smaller mean capitula size in the western and southern populations. Regression of traits on seed set showed that flowering date and capitula size are the primary determinants of fitness, and QST -FST comparisons indicated that natural selection has likely contributed to the shifts in flowering phenology and rosette size. These findings outline the potential for rescue of natural populations through contemporary evolution and emphasize the complex interplay between spatial and temporal variation in species' responses to global change.
Juha Merilä - One of the best experts on this subject based on the ideXlab platform.
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allen s rule revisited quantitative genetics of extremity length in the common frog along a Latitudinal Gradient
Journal of Evolutionary Biology, 2011Co-Authors: Jussi Alho, Anssi Laurila, Ane T Laugen, Gábor Herczeg, Katja Rasanen, Juha MeriläAbstract:Ecogeographical rules linking climate to morphology have gained renewed interest because of climate change. Yet few studies have evaluated to what extent geographical trends ascribed to these rules have a genetic, rather than environmentally determined, basis. This applies especially to Allen's rule, which states that the relative extremity length decreases with increasing latitude. We studied leg length in the common frog (Rana temporaria) along a 1500 km Latitudinal Gradient utilizing wild and common garden data. In the wild, the body size-corrected femur and tibia lengths did not conform to Allen's rule but peaked at mid-latitudes. However, the ratio of femur to tibia length increased in the north, and the common garden data revealed a genetic cline consistent with Allen's rule in some trait and treatment combinations. While selection may have shortened the leg length in the north, the genetic trend seems to be partially masked by environmental effects.
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effects of ultraviolet b radiation on common frog rana temporaria embryos from along a Latitudinal Gradient
Oecologia, 2002Co-Authors: Maarit Pahkala, Anssi Laurila, Juha MeriläAbstract:Interspecific variation in ultraviolet-B (UV-B) radiation tolerance in amphibians is well established, but little is known about the possible intraspecific variation in UV-B radiation tolerance within any species. We studied the effects of UV-B radiation on common frog Rana temporaria embryos originating from eight populations spanning a 1,200 km Latitudinal Gradient across Sweden. Newly fertilised eggs were exposed to three different UV-B treatments [absent (no UV-B), normal (1.254 kJ m–2) and enhanced (1.584 kJ m–2, 26% above normal) levels] in a laboratory, and effects on survival, frequency of developmental anomalies, developmental rate and hatchling size were documented. UV-B radiation treatments did not have main factor effects on embryonic mortality or frequency of developmental anomalies. Survival to hatching was lower at higher latitudes, but it was independent of UV-B treatments. High UV-B treatment prolonged development time in five populations, whereas in one population development time was longest in the absence of UV-B. Even though the northernmost populations had the shortest development times, the interaction between latitude and development time was not significant. There was a significant population×UV-B interaction in hatchling size, indicating that hatchling size was negatively affected by the UV-B treatments in some of the populations. Hatchling size increased until mid-latitudes and was again somewhat smaller at the northernmost latitudes, but this was independent of UV-B treatments. These results suggest that although R. temporaria embryos are rather tolerant of UV-B radiation, and there is no clear Latitudinal pattern to UV-B tolerance in this species, the sublethal effects of UV-B on embryonic development may differ among different populations.