scholarly journals The role of temperature and dispersal in moss-microarthropod community assembly after a catastrophic event

2012 ◽  
Vol 367 (1605) ◽  
pp. 3042-3049 ◽  
Author(s):  
Giselle Perdomo ◽  
Paul Sunnucks ◽  
Ross M. Thompson
Keyword(s):  
Climate Change ◽  
Community Assembly ◽  
Size Structure ◽  
Landscape Scale ◽  
Model Systems ◽  
Habitat Isolation ◽  
Catastrophic Event ◽  
Extreme Climatic Events ◽  
Effects Of Temperature

There is a clear crisis in the maintenance of biodiversity. It has been generated by a multitude of factors, notably habitat loss, now compounded by the effects of climate change. Predicted changes in climate include increased severity and frequency of extreme climatic events. To manage landscapes, an understanding of the processes that allow recovery from these extreme events is required. Understanding these landscape-scale processes of community assembly and disassembly is hindered by the large scales at which they operate. Model systems provide a means of studying landscape scale processes at tractable scales. Here, we assess the combined effects of temperature and habitat-patch isolation on assembly of naturally diverse moss microarthropod communities after a high-temperature event. We show that community assembly depends on temperature and on degree of habitat isolation. Heated communities were heavily dominated in abundance by two species, one of them relatively large. The resulting size-structure is unlike that seen in the field. Community composition in habitat fragments appears also to have been influenced by the source pool of recolonizing fauna. Our results highlight the value of dispersal in disturbed landscapes and the potential for habitat connectivity to buffer communities from the effects of climate change.

scholarly journals Clumpy coexistence in phytoplankton: The role of functional similarity in community assembly

2019 ◽  
Author(s):  
Caio Graco-Roza ◽  
Angel M Segura ◽  
Carla Kruk ◽  
Patrícia Domingos ◽  
Janne Soininen ◽  
...  
Keyword(s):  
Body Size ◽  
Community Assembly ◽  
Species Coexistence ◽  
Size Structure ◽  
Species Abundance ◽  
Functional Similarity ◽  
Neutral State ◽  
Functional Clustering ◽  
Stochastic Fluctuations

AbstractEmergent neutrality (EN) suggests that species must be sufficiently similar or sufficiently different in their niches to avoid interspecific competition. Such a scenario results in a multimodal distribution of species abundance along the niche axis (e.g., body size), namely clumps. From this perspective, species within clumps should behave in a quasi-neutral state, and their abundance will show stochastic fluctuations. Plankton is an excellent model system for developing and testing ecological theories, especially those related to size structure and species coexistence. We tested EN predictions using the phytoplankton community along the course of a tropical river considering (i) body size structure, (ii) functional clustering of species in terms of morphology-based functional groups (MBFG), and (iii) the functional similarity among species with respect to their functional traits. Considering body size as the main niche axis, two main clumps (clump I and II) were detected in different stretches of the river and remained conspicuous through time. The clump I comprised medium-sized species mainly from the MBFG IV, while the clump II included large-bodied species from the groups V and VI. Pairwise differences in species biovolume correlated with species functional redundancy when the whole species pool was considered, but not among species within the same clump. Within-clump functional distinctiveness was positively correlated with species biovolume considering both seasons, and also at the upper course. These results suggest that species within clumps behave in a quasi-neutral state, but even minor shifts in trait composition may affect their biovolume. In sum, our findings point that EN belongs to the plausible mechanisms explaining community assembly in river ecosystems.

scholarly journals Climate change in size-structured ecosystems

2012 ◽  
Vol 367 (1605) ◽  
pp. 2903-2912 ◽  
Author(s):  
Ulrich Brose ◽  
Jennifer A. Dunne ◽  
Jose M. Montoya ◽  
Owen L. Petchey ◽  
Florian D. Schneider ◽  
...  
Keyword(s):  
Climate Change ◽  
Body Size ◽  
Size Structure ◽  
The Body ◽  
Size Distributions ◽  
Ecological Communities ◽  
Average Temperature ◽  
Mechanistic Approach ◽  
Effects Of Temperature ◽  
Future Consequences

One important aspect of climate change is the increase in average temperature, which will not only have direct physiological effects on all species but also indirectly modifies abundances, interaction strengths, food-web topologies, community stability and functioning. In this theme issue, we highlight a novel pathway through which warming indirectly affects ecological communities: by changing their size structure (i.e. the body-size distributions). Warming can shift these distributions towards dominance of small- over large-bodied species. The conceptual, theoretical and empirical research described in this issue, in sum, suggests that effects of temperature may be dominated by changes in size structure, with relatively weak direct effects. For example, temperature effects via size structure have implications for top-down and bottom-up control in ecosystems and may ultimately yield novel communities. Moreover, scaling up effects of temperature and body size from physiology to the levels of populations, communities and ecosystems may provide a crucially important mechanistic approach for forecasting future consequences of global warming.

Some concluding remarks and a look ahead

2019 ◽  
pp. 334-340
Author(s):  
Gary G. Mittelbach ◽  
Brian J. McGill
Keyword(s):  
Climate Change ◽  
Community Assembly ◽  
Ecosystem Functioning ◽  
Species Interactions ◽  
Species Distributions ◽  
Ecological Communities ◽  
Look Ahead ◽  
Local And Regional Processes ◽  
Regional Processes

This chapter reflects on the successes achieved and challenges that remain in the study of ecological communities. It concludes with a discussion of research topics expected to occupy the attention of community ecologists for the next decade or so and that may yield big dividends in terms of understanding the processes that structure communities and govern their functioning. These include metacommunities and the integration of local and regional processes; the drivers of regional biodiversity; community assembly and functional traits; pathogens, parasites and natural enemies; biodiversity and ecosystem functioning; changing technology will change how we collect data; eco-evolutionary feedbacks and regional pool processes; climate change, and its effects on species distributions and species interactions; and the role of time.

The Role of Late-Night Infotainment Comedy in Communicating Climate Change Consensus

2019 ◽  
Author(s):  
Edward John Roy Clarke ◽  
Anna Klas ◽  
Joshua Stevenson ◽  
Emily Jane Kothe
Keyword(s):  
Climate Change ◽  
Policy Support ◽  
Mitigation Policy ◽  
Behavioural Intentions ◽  
Late Night ◽  
Mitigation And Adaptation ◽  
Climate Action ◽  
Adaptation Policies ◽  
Diverse Audience

Climate change is a politically-polarised issue, with conservatives less likely than liberals to perceive it as human-caused and consequential. Furthermore, they are less likely to support mitigation and adaptation policies needed to reduce its impacts. This study aimed to examine whether John Oliver’s “A Mathematically Representative Climate Change Debate” clip on his program Last Week Tonight polarised or depolarised a politically-diverse audience on climate policy support and behavioural intentions. One hundred and fifty-nine participants, recruited via Amazon MTurk (94 female, 64 male, one gender unspecified, Mage = 51.07, SDage = 16.35), were presented with either John Oliver’s climate change consensus clip, or a humorous video unrelated to climate change. Although the climate change consensus clip did not reduce polarisation (or increase it) relative to a control on mitigation policy support, it resulted in hyperpolarisation on support for adaptation policies and increased climate action intentions among liberals but not conservatives.

Regulation of microRNAs in Inflammation-Associated Colorectal Cancer: A Mechanistic Approach

2020 ◽  
Vol 20 ◽  
Author(s):  
Sridhar Muthusami ◽  
Ilangovan Ramachandran ◽  
Sneha Krishnamoorthy ◽  
Yuvaraj Sambandam ◽  
Satish Ramalingam ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Molecular Mechanisms ◽  
Colorectal Carcinogenesis ◽  
Model Systems ◽  
Necrosis Factor Alpha ◽  
Multi Stage ◽  
Mechanistic Approach ◽  
Tnf Α ◽  
Factor Alpha

: The development of colorectal cancer (CRC) is a multi-stage process. The inflammation of the colon as in inflammatory bowel disease (IBD) such as ulcerative colitis (UC) or Crohn’s disease (CD) is often regarded as the initial trigger for the development of CRC. Many cytokines such as tumor necrosis factor alpha (TNF-α) and several interleukins (ILs) are known to exert proinflammatory actions, and inflammation initiates or promotes tumorigenesis of various cancers, including CRC through differential regulation of microRNAs (miRNAs/miRs). miRNAs can be oncogenic miRNAs (oncomiRs) or anti-oncomiRs/tumor suppressor miRNAs, and they play key roles during colorectal carcinogenesis. However, the functions and molecular mechanisms of regulation of miRNAs involved in inflammation-associated CRC are still anecdotal and largely unknown. Consolidating the published results and offering perspective solutions to circumvent CRC, the current review is focused on the role of miRNAs and their regulation in the development of CRC. We have also discussed the model systems adapted by researchers to delineate the role of miRNAs in inflammation-associated CRC.

Role of inflammation in the development of colorectal cancer

2020 ◽  
Vol 20 ◽  
Author(s):  
Sridhar Muthusami ◽  
R. Ileng Kumaran ◽  
Kokelavani Nampalli Babu ◽  
Sneha Krishnamoorthy ◽  
Akash Guruswamy ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Chronic Inflammation ◽  
Interleukin 1 ◽  
Cell Types ◽  
Model Systems ◽  
Cytokine Gene Expression ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Proinflammatory Molecules

: Chronic inflammation can lead to the development of many diseases including cancer. Inflammatory bowel disease (IBD) that includes both ulcerative colitis (UC) and Crohn's disease (CD) are risk factors for the development of colorectal cancer (CRC). Many cytokines produced primarily by the gut immune cells either during or in response to localized inflammation in the colon and rectum are known to stimulate the complex interactions between the different cell types in the gut environment resulting in acute inflammation. Subsequently, chronic inflammation together with genetic and epigenetic changes has been shown to lead to the development and progression of CRC. Various cell types present in the colon such as enterocytes, Paneth cells, goblet cells and macrophages express receptors for inflammatory cytokines and respond to tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), IL-6 and other cytokines. Among the several cytokines produced, TNF-α and IL-1β are the key proinflammatory molecules that play critical roles in the development of CRC. The current review is intended to consolidate the published findings to focus on the role of proinflammatory cytokines, namely TNF-α and IL-1β, on inflammation (and the altered immune response) in the gut, to better understand the development of CRC in IBD, using various experimental model systems, preclinical and clinical studies. Moreover, this review also highlights the current therapeutic strategies available (monotherapy and combination therapy), to alleviate the symptoms or treat inflammationassociated CRC by using monoclonal antibodies or aptamers to block proinflammatory molecules, inhibitors of tyrosine kinases in inflammatory signaling cascade, competitive inhibitors of proinflammatory molecules, and the nucleic acid drugs like small activating RNAs (saRNAs) or microRNA (miRNA) mimics to activate tumor suppressor or repress oncogene/proinflammatory cytokine gene expression.

Sign in / Sign up

Export Citation Format

Share Document