Inter-Specific and Inter-Individual Trait Variability Matter in Surface Sediment Reworking Rates of Intertidal Benthic Foraminifera

Mapping Intimacies ◽

10.21203/rs.3.rs-383583/v1 ◽

2021 ◽

Author(s):

Noémie Deldicq ◽

Laurent Seuront ◽

Vincent M.P. Bouchet

Keyword(s):

Surface Sediment ◽

Benthic Foraminifera ◽

Heat Waves ◽

Critical Role ◽

Individual Variability ◽

Plastic Pollution ◽

Carbonate Production ◽

Sediment Reworking ◽

Species Specific

Abstract Although benthic foraminifera are an important component of meiofauna and contribute to carbonate production and carbon/nitrogen cycles, their role in bioturbation processes remains poorly known. Five dominant intertidal benthic foraminifera were recently classified into functional bioturbator groups according to their sediment reworking mode and intensity. Our study aimed at identifying potential drivers (i.e. size and/or travelled distance) of species-specific surface sediment reworking rate. The travelled distance and surface sediment reworking rate of Haynesina germanica, Cribroelphidium williamsoni, Ammonia tepida, Quinqueloculina seminulum and Miliammina fusca were assessed through image analysis. Our results show that the surface sediment reworking performed by these species is not size-dependent, but dependent on their motility traits through interspecific differences in the travelled distance. Smaller species (i.e. Quinqueloculina seminulum and Haynesina germanica) contribute more to surface sediment reworking than larger ones (i.e. Ammonia tepida, Cribroelphidium williamsoni and Miliammina fusca). These observations stress the critical role of motion behaviour in surface sediment reworking processes by intertidal foraminifera. Finally, we stress that the high inter-individual variability observed in conspecific motion behaviour may be important to decipher the role of foraminifera in sediment bioturbation. Noticeably, the species characterized by a strong inter-individual variability are also the species that have the highest surface sediment reworking rates. This last observation may inform on the species-specific phenotypic plasticity and therefore the potential for the functional role of these species to be maintained in their natural environment. This is particularly relevant in an era of global change where ecosystem balance is increasingly threatened by various stressors such as heat-waves, ocean acidification and plastic pollution.

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Adult hippocampal neurogenesis of mammals: evolution and life history

Biology Letters ◽

10.1098/rsbl.2008.0511 ◽

2008 ◽

Vol 5 (1) ◽

pp. 141-144 ◽

Cited By ~ 50

Author(s):

Irmgard Amrein ◽

Hans-Peter Lipp

Keyword(s):

Hippocampal Formation ◽

Mammalian Species ◽

Critical Role ◽

Hippocampal Neurogenesis ◽

Adult Hippocampal Neurogenesis ◽

Mammalian Brain ◽

Spatial Learning And Memory ◽

Species Specific ◽

Species Being

Substantial production of new neurons in the adult mammalian brain is restricted to the olfactory system and the hippocampal formation. Its physiological and behavioural role is still debated. By comparing adult hippocampal neurogenesis (AHN) across many mammalian species, one might recognize a common function. AHN is most prominent in rodents, but shows considerable variability across species, being lowest or missing in primates and bats. The latter finding argues against a critical role of AHN in spatial learning and memory. The common functional denominator across all species investigated thus far is a strong decline of AHN from infancy to midlife. As predicted by Altman and colleagues in 1973, this implies a role in transforming juvenile unpredictable to predictable behaviour, typically characterizing mammalian behaviour once reproductive competence has been attained. However, as only a fraction of mammalian species has been investigated, further comparative studies are necessary in order to recognize whether AHN has a common unique function, or whether it mediates species-specific hippocampal functions.

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Examining the relationship between herbivores, corals and macroalgae on Singapore’s heavily disturbed reefs

10.7287/peerj.preprints.1907v1 ◽

2016 ◽

Author(s):

James R Guest ◽

Adriana Vergés ◽

Andrew G Bauman ◽

Alexandra H Campbell ◽

Loke Ming Chou ◽

...

Keyword(s):

Anthropogenic Impacts ◽

Coral Cover ◽

Benthic Communities ◽

Critical Role ◽

Algal Growth ◽

Phase Shifts ◽

Human Disturbances ◽

Species Specific ◽

The Relationship

Background.Herbivores play a critical role in structuring benthic communities on tropical coral dominated reefs because they remove macro and microalgae, which might otherwise overgrow adult corals or prevent successful recruitment of juveniles. Reducing herbivory has been implicated in promoting phase shifts from coral dominance to other ecosystem states following acute disturbances. Turbidity and sedimentation are key physical processes that also structure coral reef communities because they limit light penetration and may interfere with biological processes such as heterotrophy. Singapore’s coral reefs have been heavily impacted by human activities for decades and experience very high levels of sedimentation and turbidity. Macroalgae, particularly Sargassum spp. are abundant on the reef flats, while adjacent reef slopes are dominated by diverse coral assemblages, yet nothing is known about the role of herbivory in structuring these heavily disturbed reefs. Methods. To gain a better understanding of the role of herbivore biomass and potential herbivory in structuring these disturbed reefs, we quantified benthic cover of corals and macroalgae, fish biomasses and urchin abundance at eight representative sites among Singapore’s southern islands during two seasons. In addition we filmed herbivory assays on replicate experimental macroalgal stands (4 separate macroalgal species) and natural EAM patches at three of these sites to estimate species-specific rates of herbivory. Using generalised linear mixed models we examine the relationship between herbivore abundances and benthic cover of corals and macroalgae. Results. Average coral cover at 3-4 m depth was surprisingly high (~40%) compared to other Indo-Pacific reefs, considering decades of chronic anthropogenic impacts. In contrast, the average biomass of herbivorous fishes (~4 g m-2) was more typical of degraded and overfished reefs, while urchin abundances were within the range found at other Indo-Pacific sites. Herbivorous fish were not observed feeding on macroalgal assays during 29 h of filming, with all bites counted on EAM carried out primarily by territorial damselfish. There was a significant but weak relationship between coral cover and herbivore biomass but none for macroalgae or between urchin abundance and benthic cover. Discussion. Relatively high coral cover and low macroalgal cover at 3-4 m depth has been maintained on these highly disturbed reefs, demonstrating possible resilience to coral-macroalgal phase shifts despite decades of chronic human disturbances. We suggest that low light levels at 3-4 m depth may limit algal growth rates so that only low levels of herbivory are necessary to prevent seaweeds from outcompeting corals on turbid reefs such as those in the present study.

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Inter-specific and inter-individual trait variability matter in surface sediment reworking rates of intertidal benthic foraminifera

Marine Biology ◽

10.1007/s00227-021-03908-w ◽

2021 ◽

Vol 168 (7) ◽

Author(s):

Noémie Deldicq ◽

Laurent Seuront ◽

Vincent M. P. Bouchet

Keyword(s):

Surface Sediment ◽

Benthic Foraminifera ◽

Sediment Reworking ◽

Individual Trait ◽

Trait Variability

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The Role of the SLP in Autism Spectrum Disorder Screening and Assessment

Perspectives on Language Learning and Education ◽

10.1044/lle15.2.50 ◽

2008 ◽

Vol 15 (2) ◽

pp. 50-59 ◽

Cited By ~ 1

Author(s):

Amy Philofsky

Keyword(s):

Language Development ◽

Critical Role ◽

Children With Autism ◽

Autism Spectrum ◽

Children With Asd ◽

Prevalence Estimates ◽

Notable Increase ◽

Screening Assessment ◽

Critical Components

AbstractRecent prevalence estimates for autism have been alarming as a function of the notable increase. Speech-language pathologists play a critical role in screening, assessment and intervention for children with autism. This article reviews signs that may be indicative of autism at different stages of language development, and discusses the importance of several psychometric properties—sensitivity and specificity—in utilizing screening measures for children with autism. Critical components of assessment for children with autism are reviewed. This article concludes with examples of intervention targets for children with ASD at various levels of language development.

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