Displaying publications 1 - 20 of 144 in total

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  1. Guidelines for developing a systematic literature review for studies related to climate change adaptation
    Shaffril HAM, Samah AA, Samsuddin SF
    Environ Sci Pollut Res Int, 2021 May;28(18):22265-22277.
    PMID: 33745056 DOI: 10.1007/s11356-021-13178-0
    This study proposes a set of GuFSyADD guidelines on steps for developing  suggestions that  enhance of its rigor in systematic literature review (SLR) for studies related to climate change adaptation. The prescribed guidelines are based on the following six steps, (1) guided by review of protocol/publication standard/established guidelines/related published articles, (2) formulation of review questions, (3) systematic searching strategies, (4) appraisal of quality, (5) data extraction and analysis, and (6) data demonstration. Essentially, this set of proposed  guidelines enables researchers to develop an SLR pertaining to climate change adaptation in an organised, transparent, and replicable manner.
    Matched MeSH terms: Adaptation, Physiological*
  2. Large haploblocks underlie rapid adaptation in the invasive weed Ambrosia artemisiifolia
    Battlay P, Wilson J, Bieker VC, Lee C, Prapas D, Petersen B, et al.
    Nat Commun, 2023 Mar 27;14(1):1717.
    PMID: 36973251 DOI: 10.1038/s41467-023-37303-4
    Adaptation is the central feature and leading explanation for the evolutionary diversification of life. Adaptation is also notoriously difficult to study in nature, owing to its complexity and logistically prohibitive timescale. Here, we leverage extensive contemporary and historical collections of Ambrosia artemisiifolia-an aggressively invasive weed and primary cause of pollen-induced hayfever-to track the phenotypic and genetic causes of recent local adaptation across its native and invasive ranges in North America and Europe, respectively. Large haploblocks-indicative of chromosomal inversions-contain a disproportionate share (26%) of genomic regions conferring parallel adaptation to local climates between ranges, are associated with rapidly adapting traits, and exhibit dramatic frequency shifts over space and time. These results highlight the importance of large-effect standing variants in rapid adaptation, which have been critical to A. artemisiifolia's global spread across vast climatic gradients.
    Matched MeSH terms: Adaptation, Physiological/genetics
  3. Fulltext Draft Genome Sequence of Herpotrichiellaceae sp. UM 238 Isolated from Human Skin Scraping
    Ng KP, Yew SM, Chan CL, Tan R, Soo-Hoo TS, Na SL, et al.
    Genome Announc, 2013 Jan;1(1).
    PMID: 23409267 DOI: 10.1128/genomeA.00148-12
    Herpotrichiellaceae spp. are known to be opportunistic human pathogens. Here, we report the ~28.46-Mb draft genome of Herpotrichiellaceae sp. UM 238, isolated from human skin scraping. The UM 238 genome was found to contain many classes of protective genes that are responsible for fungal adaptation under adverse environmental conditions.
    Matched MeSH terms: Adaptation, Physiological
  4. Making music: Let's not be too quick to abandon the byproduct hypothesis
    Stewart-Williams S
    Behav Brain Sci, 2021 09 30;44:e113.
    PMID: 34588037 DOI: 10.1017/S0140525X20001119
    It is premature to conclude that music is an adaptation. Given the danger of overextending the adaptationist mode of explanation, the default position should be the byproduct hypothesis, and it should take very strong evidence to drag us into the adaptationist camp. As yet, the evidence isn't strong enough - and the proposed adaptationist explanations have a number of unresolved difficulties.
    Matched MeSH terms: Adaptation, Physiological
  5. Flooding tolerance in Rice: adaptive mechanism and marker-assisted selection breeding approaches
    Haque MA, Rafii MY, Yusoff MM, Ali NS, Yusuff O, Arolu F, et al.
    Mol Biol Rep, 2023 Mar;50(3):2795-2812.
    PMID: 36592290 DOI: 10.1007/s11033-022-07853-9
    Natural and man-made ecosystems worldwide are subjected to flooding, which is a form of environmental stress. Genetic variability in the plant response to flooding involves variations in metabolism, architecture, and elongation development that are related with a low oxygen escape strategy and an opposing quiescence scheme that enables prolonged submergence endurance. Flooding is typically associated with a decrease in O2 in the cells, which is especially severe when photosynthesis is absent or limited, leading to significant annual yield losses globally. Over the past two decades, considerable advancements have been made in understanding of mechanisms of rice adaptation and tolerance to flooding/submergence. The mapping and identification of Sub1 QTL have led to the development of marker-assisted selection (MAS) breeding approach to improve flooding-tolerant rice varieties in submergence-prone ecosystems. The Sub1 incorporated in rice varieties showed tolerance during flash flood, but not during stagnant conditions. Hence, gene pyramiding techniques can be applied to combine/stack multiple resistant genes for developing flood-resilient rice varieties for different types of flooding stresses. This review contains an update on the latest advances in understanding the molecular mechanisms, metabolic adaptions, and genetic factors governing rice flooding tolerance. A better understanding of molecular genetics and adaptation mechanisms that enhance flood-tolerant varieties under different flooding regimes was also discussed.
    Matched MeSH terms: Adaptation, Physiological/genetics
  6. High-resolution chromosome-level genome of Scylla paramamosain provides molecular insights into adaptive evolution in crabs
    Zhang Y, Yuan Y, Zhang M, Yu X, Qiu B, Wu F, et al.
    BMC Biol, 2024 Nov 07;22(1):255.
    PMID: 39511558 DOI: 10.1186/s12915-024-02054-1
    BACKGROUND: Evolutionary adaptation drives organismal adjustments to environmental pressures, exemplified in the diverse morphological and ecological adaptations seen in Decapoda crustaceans, particularly brachyuran crabs. Crabs thrive in diverse ecosystems, from coral reefs to hydrothermal vents and terrestrial habitats. Despite their ecological importance, the genetic mechanisms underpinning their developmental processes, reproductive strategies, and nutrient acquisition remain poorly understood.

    RESULTS: Here, we report a comprehensive genomic analysis of the green mud crab Scylla paramamosain using ultralong sequencing technologies, achieving a high-quality chromosome-level assembly. The refined 1.21 Gb genome, with an impressive contig N50 of 11.45 Mb, offers a valuable genomic resource. The genome exhibits 33,662 protein-coding genes, enriched in various pathways related to development and environmental adaptation. Gene family analysis shows expansion in development-related pathways and contraction in metabolic pathways, indicating niche adaptations. Notably, investigation into Hox gene regulation sheds light on their role in pleopod development, with the Abd-A gene identified as a linchpin. Post-transcriptional regulation involving novel-miR1317 negatively regulates Abd-A levels. Furthermore, the potential role of fru gene in ovarian development and the identification of novel-miR35 as a regulator of Spfru2 add complexity to gene regulatory networks. Comparative functional analysis across Decapoda species reveals neo-functionalization of the elovl6 gene in the synthesis of long-chain polyunsaturated fatty acids (LC-PUFA), suggesting its importance in environmental adaptation.

    CONCLUSIONS: Our findings shed light on various aspects of crab biology, including genome sequencing, assembly, and annotation, as well as gene family expansion, contraction, and regulatory mechanisms governing crucial developmental processes such as metamorphosis, reproductive strategies, and fatty acid metabolism.

    Matched MeSH terms: Adaptation, Physiological/genetics
  7. Fulltext mRNA profile provides novel insights into stress adaptation in mud crab megalopa, Scylla paramamosain after salinity stress
    Zhang Y, Wu Q, Fang S, Li S, Zheng H, Zhang Y, et al.
    BMC Genomics, 2020 Aug 14;21(1):559.
    PMID: 32795331 DOI: 10.1186/s12864-020-06965-5
    BACKGROUND: Mud crab, Scylla paramamosain, a euryhaline crustacean species, mainly inhabits the Indo-Western Pacific region. Wild mud crab spawn in high-salt condition and the salinity reduced with the growth of the hatching larvae. When the larvae grow up to megalopa, they migrate back to estuaries and coasts in virtue of the flood tide, settle and recruit adult habitats and metamorphose into the crablet stage. Adult crab can even survive in a wide salinity of 0-35 ppt. To investigate the mRNA profile after salinity stress, S. paramamosain megalopa were exposed to different salinity seawater (low, 14 ppt; control, 25 ppt; high, 39 ppt).

    RESULTS: Firstly, from the expression profiles of Na+/K+/2Cl- cotransporter, chloride channel protein 2, and ABC transporter, it turned out that the 24 h might be the most influenced duration in the short-term stress. We collected megalopa under different salinity for 24 h and then submitted to mRNA profiling. Totally, 57.87 Gb Clean Data were obtained. The comparative genomic analysis detected 342 differentially expressed genes (DEGs). The most significantly DEGs include gamma-butyrobetaine dioxygenase-like, facilitated trehalose transporter Tret1, sodium/potassium-transporting ATPase subunit alpha, rhodanese 1-like protein, etc. And the significantly enriched pathways were lysine degradation, choline metabolism in cancer, phospholipase D signaling pathway, Fc gamma R-mediated phagocytosis, and sphingolipid signaling pathway. The results indicate that in the short-term salinity stress, the megalopa might regulate some mechanism such as metabolism, immunity responses, osmoregulation to adapt to the alteration of the environment.

    CONCLUSIONS: This study represents the first genome-wide transcriptome analysis of S. paramamosain megalopa for studying its stress adaption mechanisms under different salinity. The results reveal numbers of genes modified by salinity stress and some important pathways, which will provide valuable resources for discovering the molecular basis of salinity stress adaptation of S. paramamosain larvae and further boost the understanding of the potential molecular mechanisms of salinity stress adaptation for crustacean species.

    Matched MeSH terms: Adaptation, Physiological/genetics
  8. Can we predict ectotherm responses to climate change using thermal performance curves and body temperatures?
    Sinclair BJ, Marshall KE, Sewell MA, Levesque DL, Willett CS, Slotsbo S, et al.
    Ecol Lett, 2016 11;19(11):1372-1385.
    PMID: 27667778 DOI: 10.1111/ele.12686
    Thermal performance curves (TPCs), which quantify how an ectotherm's body temperature (Tb ) affects its performance or fitness, are often used in an attempt to predict organismal responses to climate change. Here, we examine the key - but often biologically unreasonable - assumptions underlying this approach; for example, that physiology and thermal regimes are invariant over ontogeny, space and time, and also that TPCs are independent of previously experienced Tb. We show how a critical consideration of these assumptions can lead to biologically useful hypotheses and experimental designs. For example, rather than assuming that TPCs are fixed during ontogeny, one can measure TPCs for each major life stage and incorporate these into stage-specific ecological models to reveal the life stage most likely to be vulnerable to climate change. Our overall goal is to explicitly examine the assumptions underlying the integration of TPCs with Tb , to develop a framework within which empiricists can place their work within these limitations, and to facilitate the application of thermal physiology to understanding the biological implications of climate change.
    Matched MeSH terms: Adaptation, Physiological*
  9. Unravelling the adaptation strategies employed by Glaciozyma antarctica PI12 on Antarctic sea ice
    Bharudin I, Abu Bakar MF, Hashim NHF, Mat Isa MN, Alias H, Firdaus-Raih M, et al.
    Mar Environ Res, 2018 Jun;137:169-176.
    PMID: 29598997 DOI: 10.1016/j.marenvres.2018.03.007
    Glaciozyma antarctica PI12, is a psychrophilic yeast isolated from Antarctic sea. In this work, Expressed Sequence Tags (EST) from cells exposed to three different temperatures; 15 °C, 0 °C and -12 °C were generated to identify genes associated with cold adaptation. A total of 5376 clones from each library were randomly picked and sequenced. Comparative analyses from the resulting ESTs in each condition identified several groups of genes required for cold adaptation. Additionally, 319 unique transcripts that encoded uncharacterised functions were identified in the -12 °C library and are currently unique to G. antarctica. Gene expression analysis using RT-qPCR revealed two of the unknown genes to be up-regulated at -12 °C compared to 0 °C and 15 °C. These findings further contribute to the collective knowledge into G. antarctica cold adaptation and as a resource for understanding the ecological and physiological tolerance of psychrophilic microbes in general.
    Matched MeSH terms: Adaptation, Physiological*
  10. Leaf and twig traits predict habitat adaptation and demographic strategies in tropical freshwater swamp forest trees
    Lam WN, Huang J, Tay AHT, Sim HJ, Chan PJ, Lim KE, et al.
    New Phytol, 2024 Aug;243(3):881-893.
    PMID: 38840520 DOI: 10.1111/nph.19876
    Differences in demographic and environmental niches facilitate plant species coexistence in tropical forests. However, the adaptations that enable species to achieve higher demographic rates (e.g. growth or survival) or occupy unique environmental niches (e.g. waterlogged conditions) remain poorly understood. Anatomical traits may better predict plant environmental and demographic strategies because they are direct measurements of structures involved in these adaptations. We collected 18 leaf and twig traits from 29 tree species in a tropical freshwater swamp forest in Singapore. We estimated demographic parameters of the 29 species from growth and survival models, and degree of association toward swamp habitats. We examined pairwise trait-trait, trait-demography and trait-environment links while controlling for phylogeny. Leaf and twig anatomical traits were better predictors of all demographic parameters than other commonly measured leaf and wood traits. Plants with wider vessels had faster growth rates but lower survival rates. Leaf and spongy mesophyll thickness predicted swamp association. These findings demonstrate the utility of anatomical traits as indicators of plant hydraulic strategies and their links to growth-mortality trade-offs and waterlogging stress tolerance that underlie species coexistence mechanisms in tropical forest trees.
    Matched MeSH terms: Adaptation, Physiological*
  11. Fulltext A second species of Cheleion from Johor, Malaysia (Coleoptera, Scarabaeidae, Aphodiinae, Stereomerini)
    Král D, Hájek J
    Zookeys, 2015.
    PMID: 26692807 DOI: 10.3897/zookeys.532.6116
    A new species of the genus Cheleion Vårdal & Forshage, 2010, Cheleion jendeki sp. n., from Johor, Malaysia is described, illustrated and compared with the type species of the genus, Cheleion malayanum Vårdal & Forshage, 2010. Photographs of the two species are presented. The adaptation to inquilinous lifestyle of Cheleion is compared with those in other beetle groups and briefly discussed.
    Matched MeSH terms: Adaptation, Physiological
  12. Fulltext Association between shell morphology of micro-land snails (genus Plectostoma) and their predator's predatory behaviour
    Liew TS, Schilthuizen M
    PeerJ, 2014;2:e329.
    PMID: 24749008 DOI: 10.7717/peerj.329
    Predator-prey interactions are among the main ecological interactions that shape the diversity of biological form. In many cases, the evolution of the mollusc shell form is presumably driven by predation. However, the adaptive significance of several uncommon, yet striking, shell traits of land snails are still poorly known. These include the distorted coiled "tuba" and the protruded radial ribs that can be found in micro-landsnails of the genus Plectostoma. Here, we experimentally tested whether these shell traits may act as defensive adaptations against predators. We characterised and quantified the possible anti-predation behaviour and shell traits of Plectostoma snails both in terms of their properties and efficiencies in defending against the Atopos slug predatory strategies, namely, shell-apertural entry and shell-drilling. The results showed that Atopos slugs would first attack the snail by shell-apertural entry, and, should this fail, shift to the energetically more costly shell-drilling strategy. We found that the shell tuba of Plectostoma snails is an effective defensive trait against shell-apertural entry attack. None of the snail traits, such as resting behaviour, shell thickness, shell tuba shape, shell rib density and intensity can fully protect the snail from the slug's shell-drilling attack. However, these traits could increase the predation costs to the slug. Further analysis on the shell traits revealed that the lack of effectiveness in these anti-predation shell traits may be caused by a functional trade-off between shell traits under selection of two different predatory strategies.
    Matched MeSH terms: Adaptation, Physiological
  13. Fulltext Understanding human vulnerability to climate change: A global perspective on index validation for adaptation planning
    Birkmann J, Jamshed A, McMillan JM, Feldmeyer D, Totin E, Solecki W, et al.
    Sci Total Environ, 2022 Jan 10;803:150065.
    PMID: 34525713 DOI: 10.1016/j.scitotenv.2021.150065
    Climate change is a severe global threat. Research on climate change and vulnerability to natural hazards has made significant progress over the last decades. Most of the research has been devoted to improving the quality of climate information and hazard data, including exposure to specific phenomena, such as flooding or sea-level rise. Less attention has been given to the assessment of vulnerability and embedded social, economic and historical conditions that foster vulnerability of societies. A number of global vulnerability assessments based on indicators have been developed over the past years. Yet an essential question remains how to validate those assessments at the global scale. This paper examines different options to validate global vulnerability assessments in terms of their internal and external validity, focusing on two global vulnerability indicator systems used in the WorldRiskIndex and the INFORM index. The paper reviews these global index systems as best practices and at the same time presents new analysis and global results that show linkages between the level of vulnerability and disaster outcomes. Both the review and new analysis support each other and help to communicate the validity and the uncertainty of vulnerability assessments. Next to statistical validation methods, we discuss the importance of the appropriate link between indicators, data and the indicandum. We found that mortality per hazard event from floods, drought and storms is 15 times higher for countries ranked as highly vulnerable compared to those classified as low vulnerable. These findings highlight the different starting points of countries in their move towards climate resilient development. Priority should be given not just to those regions that are likely to face more severe climate hazards in the future but also to those confronted with high vulnerability already.
    Matched MeSH terms: Adaptation, Physiological
  14. Fulltext Transcriptional landscape of Burkholderia pseudomallei cultured under environmental and clinical conditions
    Kong C, Wong RR, Ghazali AK, Hara Y, Tengku Aziz TN, Nathan S
    Microb Genom, 2023 Apr;9(4).
    PMID: 37018040 DOI: 10.1099/mgen.0.000982
    Burkholderia pseudomallei, a Gram-negative pathogen, is the causative agent of melioidosis in humans. This bacterium can be isolated from the soil, stagnant and salt-water bodies, and human and animal clinical specimens. While extensive studies have contributed to our understanding of B. pseudomallei pathogenesis, little is known about how a harmless soil bacterium adapts when it shifts to a human host and exhibits its virulence. The bacterium's large genome encodes an array of factors that support the pathogen's ability to survive under stressful conditions, including the host's internal milieu. In this study, we performed comparative transcriptome analysis of B. pseudomallei cultured in human plasma versus soil extract media to provide insights into B. pseudomallei gene expression that governs bacterial adaptation and infectivity in the host. A total of 455 genes were differentially regulated; genes upregulated in B. pseudomallei grown in human plasma are involved in energy metabolism and cellular processes, whilst the downregulated genes mostly include fatty acid and phospholipid metabolism, amino acid biosynthesis and regulatory function proteins. Further analysis identified a significant upregulation of biofilm-related genes in plasma, which was validated using the biofilm-forming assay and scanning electron microscopy. In addition, genes encoding known virulence factors such as capsular polysaccharide and flagella were also overexpressed, suggesting an overall enhancement of B. pseudomallei virulence potential when present in human plasma. This ex vivo gene expression profile provides comprehensive information on B. pseudomallei's adaptation when shifted from the environment to the host. The induction of biofilm formation under host conditions may explain the difficulty in treating septic melioidosis.
    Matched MeSH terms: Adaptation, Physiological
  15. Fulltext Widespread ancient whole-genome duplications in Malpighiales coincide with Eocene global climatic upheaval
    Cai L, Xi Z, Amorim AM, Sugumaran M, Rest JS, Liu L, et al.
    New Phytol, 2019 Jan;221(1):565-576.
    PMID: 30030969 DOI: 10.1111/nph.15357
    Whole-genome duplications (WGDs) are widespread and prevalent in vascular plants and frequently coincide with major episodes of global and climatic upheaval, including the mass extinction at the Cretaceous-Tertiary boundary (c. 65 Ma) and during more recent periods of global aridification in the Miocene (c. 10-5 Ma). Here, we explore WGDs in the diverse flowering plant clade Malpighiales. Using transcriptomes and complete genomes from 42 species, we applied a multipronged phylogenomic pipeline to identify, locate, and determine the age of WGDs in Malpighiales using three means of inference: distributions of synonymous substitutions per synonymous site (Ks ) among paralogs, phylogenomic (gene tree) reconciliation, and a likelihood-based gene-count method. We conservatively identify 22 ancient WGDs, widely distributed across Malpighiales subclades. Importantly, these events are clustered around the Eocene-Paleocene transition (c. 54 Ma), during which time the planet was warmer and wetter than any period in the Cenozoic. These results establish that the Eocene Climatic Optimum likely represents a previously unrecognized period of prolific WGDs in plants, and lends further support to the hypothesis that polyploidization promotes adaptation and enhances plant survival during episodes of global change, especially for tropical organisms like Malpighiales, which have tight thermal tolerances.
    Matched MeSH terms: Adaptation, Physiological
  16. Adaptational properties and applications of cold-active lipases from psychrophilic bacteria
    Maiangwa J, Ali MS, Salleh AB, Rahman RN, Shariff FM, Leow TC
    Extremophiles, 2015 Mar;19(2):235-47.
    PMID: 25472009 DOI: 10.1007/s00792-014-0710-5
    Psychrophilic microorganisms are cold-adapted with distinct properties from other thermal classes thriving in cold conditions in large areas of the earth's cold environment. Maintenance of functional membranes, evolving cold-adapted enzymes and synthesizing a range of structural features are basic adaptive strategies of psychrophiles. Among the cold-evolved enzymes are the cold-active lipases, a group of microbial lipases with inherent stability-activity-flexibility property that have engaged the interest of researchers over the years. Current knowledge regarding these cold-evolved enzymes in psychrophilic bacteria proves a display of high catalytic efficiency with low thermal stability, which is a differentiating feature with that of their mesophilic and thermophilic counterparts. Improvement strategies of their adaptive structural features have significantly benefited the enzyme industry. Based on their homogeneity and purity, molecular characterizations of these enzymes have been successful and their properties make them unique biocatalysts for various industrial and biotechnological applications. Although, strong association of lipopolysaccharides from Antarctic microorganisms with lipid hydrolases pose a challenge in their purification, heterologous expression of the cold-adapted lipases with affinity tags simplifies purification with higher yield. The review discusses these cold-evolved lipases from bacteria and their peculiar properties, in addition to their potential biotechnological and industrial applications.
    Matched MeSH terms: Adaptation, Physiological*
  17. Differentiation and adaptive radiation of amphibious gobies (Gobiidae: Oxudercinae) in semi-terrestrial habitats
    Polgar G, Sacchetti A, Galli P
    J Fish Biol, 2010 Nov;77(7):1645-64.
    PMID: 21078024 DOI: 10.1111/j.1095-8649.2010.02807.x
    During several surveys made in the region of the lower Fly River and delta, Papua New Guinea, nine species of oxudercine gobies (Gobiidae: Oxudercinae) were recorded: Boleophthalmus caeruleomaculatus, Oxuderces wirzi, Periophthalmodon freycineti, Periophthalmus darwini, Periophthalmus novaeguineaensis, Periophthalmus takita, Periophthalmus weberi, Scartelaos histophorus and Zappa confluentus. An exploratory multivariate analysis of their habitat conditions discriminated five guilds, differentially distributed in habitats with different quantities of environmental water and three guilds corresponding to different levels of salinity. A partial correspondence between phylogenetic and ecological categories suggested the presence of parallel adaptive radiations within different genera. In particular, the species found in the most terrestrial habitats (P. weberi) was also found in the widest range of conditions, suggesting that colonization of extreme semi-terrestrial and freshwater habitats by this species was facilitated by eurytypy. It is proposed that these findings provide insight into convergent adaptations for the vertebrate eco-evolutionary transition from sea to land.
    Matched MeSH terms: Adaptation, Physiological/physiology*
  18. Effect of carbon dioxide and bicarbonate as inorganic carbon sources on growth and adaptation of autohydrogenotrophic denitrifying bacteria
    Ghafari S, Hasan M, Aroua MK
    J Hazard Mater, 2009 Mar 15;162(2-3):1507-13.
    PMID: 18639979 DOI: 10.1016/j.jhazmat.2008.06.039
    Acclimation of autohydrogenotrophic denitrifying bacteria using inorganic carbon source (CO(2) and bicarbonate) and hydrogen gas as electron donor was performed in this study. In this regard, activated sludge was used as the seed source and sequencing batch reactor (SBR) technique was applied for accomplishing the acclimatization. Three distinct strategies in feeding of carbon sources were applied: (I) continuous sparging of CO(2), (II) bicarbonate plus continuous sparging of CO(2), and (III) only bicarbonate. The pH-reducing nature of CO(2) showed an unfavorable impact on denitrification rate; however bicarbonate resulted in a buffered environment in the mixed liquor and provided a suitable mean to maintain the pH in the desirable range of 7-8.2. As a result, bicarbonate as the only carbon source showed a faster adaptation, while carbon dioxide as the only carbon source as well as a complementary carbon source added to bicarbonate resulted in longer acclimation period. Adapted hydrogenotrophic denitrifying bacteria, using bicarbonate and hydrogen gas in the aforementioned pH range, caused denitrification at a rate of 13.33 mg NO(3)(-)-N/g MLVSS/h for degrading 20 and 30 mg NO(3)(-)-N/L and 9.09 mg NO(3)(-)-N/g MLVSS/h for degrading 50mg NO(3)(-)-N/L.
    Matched MeSH terms: Adaptation, Physiological*
  19. The effect of multi-generational exposure to metals and resultant change in median lethal toxicity tests values over subsequent generations
    Vedamanikam VJ, Shazilli NA
    Bull Environ Contam Toxicol, 2008 Jan;80(1):63-7.
    PMID: 18058048
    A study was conducted on the long term effects of nine heavy metals on the Chironomus plumosus and Culicoides furens larvae. This study tested the effect of the heavy metals on several generations of the larvae to observe the formation of increased hardiness against pollutants present within the aquatic habitat. From this study it was observed that susceptibility or sensitivity to heavy metals decreased with LC50 values becoming larger indicating a decreased toxicity level. Significant variations (p < 0.05) were observed between first generation and third generation culicoides for all metals and at all concentrations. Variations between third and fourth generation culicoides were also significantly different (p < 0.05) with the exception of chromium at 25 degrees C and nickel and lead at every temperature range group. The variation between all generations 4, 5 and 6 was found to be insignificant (p > 0.05). This would indicate that metal tolerance would have occurred in these generations and the effect of metals was less toxic to the culicoides. Generation 9 was found to have LC50 values (p > 0.05) the same as the LC50 values obtained in third generation culicoides. Thus it would appear that heavy metal resistance was developed when the organisms were exposed to prolonged exposure of the heavy metals but was lost when the organisms were bred in non-contaminated water.
    Matched MeSH terms: Adaptation, Physiological*
  20. Experimental evidence for the effects of dung beetle functional group richness and composition on ecosystem function in a tropical forest
    Slade EM, Mann DJ, Villanueva JF, Lewis OT
    J Anim Ecol, 2007 Nov;76(6):1094-104.
    PMID: 17922706
    Much of the literature on the relationship between species richness or functional group richness and measures of ecosystem function focuses on a restricted set of ecosystem function measures and taxonomic groups. Few such studies have been carried out under realistic levels of diversity in the field, particularly in high diversity ecosystems such as tropical forests. We used exclusion experiments to study the effects of dung beetle functional group richness and composition on two interlinked and functionally important ecological processes, dung removal and secondary seed dispersal, in evergreen tropical forest in Sabah, Malaysian Borneo. Overall, both dung and seed removal increased with dung beetle functional group richness. However, levels of ecosystem functioning were idiosyncratic depending on the identity of the functional groups present, indicating an important role for functional group composition. There was no evidence for interference or competition among functional groups. We found strong evidence for overyielding and transgressive overyielding, suggesting complementarity or facilitation among functional groups. Not all mixtures showed transgressive overyielding, so that complementarity was restricted to particular functional group combinations. Beetles in a single functional group (large nocturnal tunnellers) had a disproportionate influence on measures of ecosystem function: in their absence dung removal is reduced by approximately 75%. However, a full complement of functional groups is required to maximize ecosystem functioning. This study highlights the importance of both functional group identity and species composition in determining the ecosystem consequences of extinctions or altered patterns in the relative abundance of species.
    Matched MeSH terms: Adaptation, Physiological*
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