Convergent evolution of niche structure in Northeast Pacific kelp forests

AbstractMuch of the morphological and ecological diversity present on earth is believed to have arisen through the process of adaptive radiation. Yet, this is seemingly at odds with substantial evidence that niches tend to be similar among closely related species (i.e., niche conservatism). Identifying the relative importance of these opposing processes in different circumstances is therefore essential to our understanding of the interaction between ecological and evolutionary phenomena.In this study, we make use of recent advances in our understanding of the phylogeny of kelps (Laminariales) to investigate niche evolution in one of the most important groups of benthic habitat-forming organisms on the planet. We quantify functional traits and use community sampling data from a kelp diversity hotspot to determine which traits are responsible for the habitat (β) niche of kelps and whether they are labile or conserved across the kelp phylogeny.We find that combinations of functional traits have evolved convergently across kelp subclades and that these traits are significant predictors of community structure. Specifically, traits associated with whole-kelp structural reinforcement and material properties were found to be significantly correlated with species distributions along a gradient of wave disturbance and thus predict the outcome of environmental filtering. However, kelp assemblages were made up of species that are more phylogenetically distinct than predicted from null models (i.e., phylogenetic overdispersion), suggesting that niche partitioning along this gradient of wave disturbance has been an important driver of divergence between close relatives.These results collectively demonstrate that environmental filtering by waves plays an essential role in determining the habitat niche of kelps across local communities and further suggest that this community-level process can drive phenotypic divergence between close relatives. We propose that parallel adaptive radiation of kelp subclades has shaped the diversity and species composition of kelp forests in the Northeast Pacific and we discuss how evidence from the literature on incipient or ongoing speciation events support this hypothesis.

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Southward decrease in the protection of persistent giant kelp forests in the northeast Pacific

Communications Earth & Environment ◽

10.1038/s43247-021-00177-9 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Nur Arafeh-Dalmau ◽

Kyle C. Cavanaugh ◽

Hugh P. Possingham ◽

Adrian Munguia-Vega ◽

Gabriela Montaño-Moctezuma ◽

...

Keyword(s):

Baja California ◽

Marine Reserves ◽

Fold Increase ◽

Kelp Forests ◽

Giant Kelp ◽

Central California ◽

Northeast Pacific ◽

The Face ◽

High Resolution Satellite Imagery ◽

Northeast Pacific Ocean

AbstractKelp forests are globally important and highly productive ecosystems, yet their persistence and protection in the face of climate change and human activity are poorly known. Here, we present a 35-year time series of high-resolution satellite imagery that maps the distribution and persistence of giant kelp (Macrocystis pyrifera) forests along ten degrees of latitude in the Northeast Pacific Ocean. We find that although 7.7% of giant kelp is protected by marine reserves, when accounting for persistence only 4% of kelp is present and protected. Protection of giant kelp decreases southerly from 20.9% in Central California, USA, to less than 1% in Baja California, Mexico, which likely exacerbates kelp vulnerability to marine heatwaves in Baja California. We suggest that a two-fold increase in the area of kelp protected by marine reserves is needed to fully protect persistent kelp forests and that conservation of climate-refugia in Baja California should be a priority.

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Niche partitioning in the Rimicaris exoculata holobiont: the case of the first symbiotic Zetaproteobacteria

Microbiome ◽

10.1186/s40168-021-01045-6 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Marie-Anne Cambon-Bonavita ◽

Johanne Aubé ◽

Valérie Cueff-Gauchard ◽

Julie Reveillaud

Keyword(s):

Hydrothermal Vents ◽

Carbon Fixation ◽

Iron Sulfide ◽

Hydrogen Oxidation ◽

Niche Partitioning ◽

Sulfur Oxidation ◽

Single Copy ◽

Trophic Levels ◽

Rimicaris Exoculata ◽

Close Relatives

Abstract Background Free-living and symbiotic chemosynthetic microbial communities support primary production and higher trophic levels in deep-sea hydrothermal vents. The shrimp Rimicaris exoculata, which dominates animal communities along the Mid-Atlantic Ridge, houses a complex bacterial community in its enlarged cephalothorax. The dominant bacteria present are from the taxonomic groups Campylobacteria, Desulfobulbia (formerly Deltaproteobacteria), Alphaproteobacteria, Gammaproteobacteria, and some recently discovered iron oxyhydroxide-coated Zetaproteobacteria. This epibiotic consortium uses iron, sulfide, methane, and hydrogen as energy sources. Here, we generated shotgun metagenomes from Rimicaris exoculata cephalothoracic epibiotic communities to reconstruct and investigate symbiotic genomes. We collected specimens from three geochemically contrasted vent fields, TAG, Rainbow, and Snake Pit, to unravel the specificity, variability, and adaptation of Rimicaris–microbe associations. Results Our data enabled us to reconstruct 49 metagenome-assembled genomes (MAGs) from the TAG and Rainbow vent fields, including 16 with more than 90% completion and less than 5% contamination based on single copy core genes. These MAGs belonged to the dominant Campylobacteria, Desulfobulbia, Thiotrichaceae, and some novel candidate phyla radiation (CPR) lineages. In addition, most importantly, two MAGs in our collection were affiliated to Zetaproteobacteria and had no close relatives (average nucleotide identity ANI < 77% with the closest relative Ghiorsea bivora isolated from TAG, and 88% with each other), suggesting potential novel species. Genes for Calvin-Benson Bassham (CBB) carbon fixation, iron, and sulfur oxidation, as well as nitrate reduction, occurred in both MAGs. However, genes for hydrogen oxidation and multicopper oxidases occurred in one MAG only, suggesting shared and specific potential functions for these two novel Zetaproteobacteria symbiotic lineages. Overall, we observed highly similar symbionts co-existing in a single shrimp at both the basaltic TAG and ultramafic Rainbow vent sites. Nevertheless, further examination of the seeming functional redundancy among these epibionts revealed important differences. Conclusion These data highlight microniche partitioning in the Rimicaris holobiont and support recent studies showing that functional diversity enables multiple symbiont strains to coexist in animals colonizing hydrothermal vents.

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Empowering conservation practice with efficient and economical genotyping from poor quality samples

10.1101/349472 ◽

2018 ◽

Cited By ~ 2

Author(s):

Meghana Natesh ◽

Ryan W. Taylor ◽

Nathan Truelove ◽

Elizabeth A. Hadly ◽

Stephen Palumbi ◽

...

Keyword(s):

Population Structure ◽

Genetic Material ◽

Cost Effective ◽

Poor Quality ◽

Wildlife Trade ◽

List Type ◽

High Quality ◽

Conservation Practice ◽

Queen Conch ◽

Close Relatives

AbstractModerate to high density genotyping (100+ SNPs) is widely used to determine and measure individual identity, relatedness, fitness, population structure and migration in wild populations.However, these important tools are difficult to apply when high-quality genetic material is unavailable. Most genomic tools are developed for high quality DNA sources from labor medical settings. As a result, most genetic data from market or field settings is limited to easily amplified mitochondrial DNA or a few microsatellites.To enable genotyping in conservation contexts, we used next-generation sequencing of multiplex PCR products from very low-quality DNA extracted from feces, hair, and cooked samples. We demonstrated utility and wide-ranging potential application in endangered wild tigers and tracking commercial trade in Caribbean queen conch.We genotyped 100 SNPs from degraded tiger samples to identify individuals, discern close relatives, and detect population differentiation. Co-occurring carnivores do not amplify (e.g. Indian wild dog/Dhole) or are monomorphic (e.g. leopard). 62 SNPs from conch fritters and field-collected samples were used to test relatedness and detect population structure.We provide proof-of-concept for a rapid, simple, cost-effective, and scalable method (for both samples and number of loci), a framework that can be applied to other conservation scenarios previously limited by low quality DNA samples. These approaches provide a critical advance for wildlife monitoring and forensics, open the door to field-ready testing, and will strengthen the use of science in policy decisions and wildlife trade.

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Mobula kuhlii cleaning station identified at an inshore reef in southern Mozambique

10.7287/peerj.preprints.1724 ◽

2016 ◽

Author(s):

Calum JG Murie ◽

Andrea D Marshall

Keyword(s):

Niche Partitioning ◽

Labroides Dimidiatus ◽

Cleaning Station ◽

Inshore Reef ◽

Close Relatives ◽

Distinct Body

Cleaning interactions between the short fin devil ray, Mobula kuhlii, and the blue streaked cleaner wrasse, Labroides dimidiatus, were observed at two sites on a single reef in southern Mozambique. Cleaning interactions were filmed and described, with the number and location of interactions recorded and subsequently binned into six distinct body patches. Cleaners preferentially foraged within certain ray body patches, and this was found to vary between the two sites, possibly signifying that variations in a habitats composition can influence cleaning. Mobula kuhlii were not found to clean sympatrically with their close relatives in the Manta genus, implying their cleaning requires a distinct habitat or that niche partitioning is required to stem competition for host cleaner fishes attention. In total, 15 individuals were observed interacting with cleaners, and they never arrived alone, suggesting they may travel to cleaning areas in an aggregative manner.

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PRACTICAL SCREENING FOR DIABETES MELLITUS IN PREGNANT WOMEN

Acta Endocrinologica ◽

10.1530/acta.0.075s011 ◽

1974 ◽

Vol 77 (3_Suppl) ◽

pp. S11-S24 ◽

Cited By ~ 29

Author(s):

Eigil Guttorm

Keyword(s):

Pregnant Women ◽

Plasma Glucose ◽

Fasting Plasma Glucose ◽

Screening Method ◽

Control Group ◽

List Type ◽

Fasting Plasma ◽

Class B ◽

Close Relatives ◽

In Pregnancy

ABSTRACT A prospective and consecutive investigation of 1697 pregnant women without earlier known diabetes and a retrospective investigation of 120 pregnant diabetics (White class A: 94, White class B: 26), has been performed. It was found that: the most useful criteria of potential diabetics were: 1) the presence of diabetes in close relatives, diagnosed before the age of 40 years, 2) the presence of obesity in the patients, defined as 20 per cent overweight or more just before pregnancy, 3) previous delivery of a big baby, defined as a baby with birthweight ≦ 4500 g. Of the 1697 pregnant women 8 per cent were potential diabetics and in 8 per cent glucosuria was found. pregnant women with glucosuria and potential diabetics defined as above had a higher risk of having a diabetic OGTT than other pregnant women. A diabetic OGTT was found with falling incidence in the groups: potential diabetics with glucosuria: 10.5 per cent, non-potential diabetics with glucosuria: 3.7 per cent, potential diabetics without glucosuria: 3.4 per cent, and in the control group (non-potential diabetics without glucosuria): 0.3 per cent. A positive correlation was found between the level of fasting plasma glucose (FPG) early in pregnancy, and the result of OGTT later in pregnancy. When FPG exceeded 89 mg/100 ml (75 mg/100 ml whole blood) the incidence of diabetic curves increased significantly. By combining the following criteria: potential diabetics – glucosuria – fasting plasma glucose, FPG, it was found that the percentage of pregnant women, which ought to be investigated with an OGTT, could be reduced to 4 per cent, while the sensitivity and the specificity of the screening was 78 per cent and 89 per cent, respectively. This approach also resulted in the detection of all the most treatmentrequiring cases of diabetes. The practical use of the screening method is described.

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Soil variation response is mediated by growth trajectories rather than functional traits in a widespread pioneer Neotropical tree

10.1101/351197 ◽

2018 ◽

Cited By ~ 1

Author(s):

Sébastien Levionnois ◽

Niklas Tysklind ◽

Eric Nicolini ◽

Bruno Ferry ◽

Valérie Troispoux ◽

...

Keyword(s):

Functional Traits ◽

Soil Types ◽

Tree Level ◽

Growth Trajectories ◽

List Type ◽

Residual Water ◽

Growth Strategies ◽

Soil Response ◽

Neotropical Tree ◽

Adult Trees

AbstractTrait-environment relationships have been described at the community level across tree species. However, whether interspecific trait-environment relationships are consistent at the intraspecific level is yet unknown. Moreover, we do not know how consistent is the response between organ vs. whole-tree level.We examined phenotypic variability for 16 functional leaf (dimensions, nutrient, chlorophyll) and wood traits (density) across two soil types, Ferralitic Soil (FS) vs. White Sands (WS), on two sites for 70 adult trees of Cecropia obtusa Trécul (Urticaceae) in French Guiana. Cecropia is a widespread pioneer Neotropical genus that generally dominates early successional forest stages. To understand how soil types impact resource-use through the processes of growth and branching, we examined the architectural development with a retrospective analysis of growth trajectories. We expect soil types to affect both, functional traits in relation to resource acquisition strategy as already described at the interspecific level, and growth strategies due to resource limitations with reduced growth on poor soils.Functional traits were not involved in the soil response, as only two traits-leaf residual water content and K content-showed significant differences across soil types. Soil effects were stronger on growth trajectories, with WS trees having the slowest growth trajectories and less numerous branches across their lifespan.The analysis of growth trajectories based on architectural analysis improved our ability to characterise the response of trees with soil types. The intraspecific variability is higher for growth trajectories than functional traits for C. obtusa, revealing the complementarity of the architectural approach with the functional approach to gain insights on the way trees manage their resources over their lifetime. Soil-related responses of Cecropia functional traits are not the same as those at the interspecific level, suggesting that the effects of the acting ecological processes are different between the two levels. Apart from soil differences, much variation was found across sites, which calls for further investigation of the factors shaping growth trajectories in tropical forests.

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Maternal effects and environmental filtering shape seed fungal communities in oak trees

10.1101/691121 ◽

2019 ◽

Cited By ~ 2

Author(s):

Tania Fort ◽

Charlie Pauvert ◽

Amy E. Zanne ◽

Otso Ovaskainen ◽

Thomas Caignard ◽

...

Keyword(s):

Microbial Communities ◽

Maternal Effects ◽

Environmental Filtering ◽

Fungal Communities ◽

Future Research ◽

Phenotypic Traits ◽

List Type ◽

Elevation Gradients ◽

Sessile Oak ◽

Starting Point

SummaryTrees, as foundation species, play a pivotal role in the species interaction networks that constitute forest ecosystems. From the seed stage, they interact with microbial communities that affect their growth, health and fitness. Despite their eco-evolutionary importance, the processes shaping seed microbial communities in natural forests have received little attention.To unravel these processes, we analyzed the microbial communities of seeds collected in populations of sessile oak (Quercus petraea) growing along elevation gradients. We focused on the fungal communities as this group includes seed pathogens. Ecological processes shaping the communities were quantified using joint species distribution models.Fungi were present in all seed tissues, including the embryo. Fungal communities differed significantly among oak populations along the elevation gradients, and among mother trees within the same population. These maternal effects remained significant after seed fall, despite colonization by fungal species on the ground. Associations between tree pathogens and their antagonists were detected in the seeds.Our results demonstrate that both maternal effects and environmental filtering shape seed microbial communities of sessile oak. They provide a starting point for future research aimed at identifying the seed extended phenotypic traits that influence seed dispersal and germination, and seedling survival and growth across environments.

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Eco-evolutionary dynamics of prior selfing rate promotes the coexistence without niche partitioning under reproductive interference

10.1101/2020.04.07.029082 ◽

2020 ◽

Author(s):

Koki R. Katsuhara ◽

Yuuya Tachiki ◽

Ryosuke Iritani ◽

Atushi Ushimaru

Keyword(s):

Population Density ◽

Plant Species ◽

Inbreeding Depression ◽

Evolutionary Dynamics ◽

Niche Partitioning ◽

Reproductive Interference ◽

List Type ◽

Selfing Rate ◽

Evolutionary Rescue

AbstractWhen the two or more plants species share the same pollinators, pollinator-mediated reproductive interference make coexistence difficult. Recent studies suggested prior autonomous selfing mitigate reproductive interference, could enabling coexistence without pollination niche partitioning (pre-emptive selfing hypothesis). However, there are no studies to test whether evolution of prior selfing promote the coexistence, considering eco-evolutionary dynamics of population size, selfing rate and inbreeding depression.To examine conditions that the evolution of prior selfing promote coexistence under mutual reproductive interference especially in the point of view for pollinator availability and dynamics of inbreeding depression, we constructed individual-based model in which two plant species compete against each other in the form of mutual reproductive interference and can evolve prior autonomous selfing rate. We expected that purging of deleterious mutations could cause evolutionary rescue because inferior species could rescue population density through the evolution of prior selfing if the strength of inbreeding depression decreases with an increase of population’s selfing rate.Our simulation demonstrated that the evolution of prior selfing could promote the coexistence while reproductive interference caused competitive exclusion without evolution. We found that lower pollinator availability tended to prefer rapid evolutionary shift to higher prior selfing rate, it neutralizes the negative effect of reproductive interference, and population dynamics exhibit neutral random walk in both species. When the strength of inbreeding depression decreased with an increase in population’s selfing rate, moderate pollinator availability resulted in long-term coexistence in which relative-abundance-dependent selection on the prior selfing rate rescue population density of inferior species intermittently.Synthesis. We showed that the evolution of prior selfing could increase population growth rate of inferior species and consequently enable the long-term coexistence with evolutionary rescue. This is the new mechanisms explaining co-evolutionary coexistence of closely related plant species without niche partitioning and consistent with recent studies reported that closely related mixed-mating species are sympatrically growing even under the mutual reproductive interference.

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Uneven protection of persistent giant kelp forest in the Northeast Pacific Ocean

10.1101/2020.12.15.422778 ◽

2020 ◽

Author(s):

Nur Arafeh-Dalmau ◽

Kyle Cavanaugh ◽

Hugh Possingham ◽

Adrian Munguia-Vega ◽

Gabriela Montano-Moctezuma ◽

...

Keyword(s):

Pacific Ocean ◽

Kelp Forest ◽

Kelp Forests ◽

Giant Kelp ◽

Northeast Pacific ◽

Habitat Dynamics ◽

Climate Adaption ◽

Northeast Pacific Ocean

In most regions, the distribution of marine forests and the efficacy of their protection is unknown. We mapped the persistence of giant kelp forests across ten degrees of latitude in the Northeast Pacific Ocean and found that 7.7% of giant kelp is fully protected, with decreasing percentages from north to south. Sustainability goals should prioritize kelp mapping and monitoring, while protection and climate adaption targets should account for habitat dynamics.

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