November 2024 I Autre événement I Cesab I Autres sujets
![[FRB-CESAB] CESABINARs](https://www.fondationbiodiversite.fr/wp-content/uploads/2024/11/CESAB-Cesabinar-Webinar.jpg)
[FRB-CESAB] CESABINARs
CESABINARs are monthly webinars designed to provide FRB-CESAB research groups with a platform to present their key findings once their residency has ended. Open to the entire scientific community, these webinars offer the opportunity to discover the advancements and work emerging from FRB-CESAB.
CESABINARs, which are held in English on Zoom, last approximately one hour: 40 minutes are dedicated to the presentation, followed by 20 minutes of discussion for questions and deeper exploration of the topics covered.
Here, you will find all the information about the upcoming CESABINAR as well as information and recordings of previous sessions.
We look forward to seeing you on Zoom!
NEXT CESABINAR
Join us on Thursday, December 12, at 3:00 PM (CST) for the fifth Cesabinar! Sonia Chaabane and Thibault de Garidel will guide us through the findings of the FORCIS group.
Meeting ID: 883 0961 5680 ; Secret code: 941365
Foraminifera response to Climatic Stress: evaluating biodiversity changes of calcifying zooplankton in response to multiple stressors
Rising CO2 emissions are driving ocean warming and acidification, disrupting marine ecosystems and threatening calcifying organisms like planktonic foraminifera. These organisms, with their well-preserved fossils in sediments, serve as excellent paleo-environmental indicators. However, their ability to adapt to the rapid pace of modern environmental changes remains uncertain, and a global-scale assessment of their historical distribution is lacking.
The FORCIS project addressed these uncertainties by compiling a comprehensive database of planktonic foraminifera diversity and distribution from 1910 to the present. With over 180,000 samples collected from various depths and sampling devices, this dataset enabled analyses of species abundance across size classes, and depth. A new size normalization scheme facilitated comparisons across data sampled with different mesh sizes.
Our analysis revealed clear evidence of poleward migrations, with species diversity increasing at mid- to high-latitudes and some species moving deeper into the water column to escape warming surface waters. Additionally, foraminifera abundance declined by 24% over the past eight decades at these latitudes. Projections for ocean conditions in 2050 and 2100 suggest that low-latitude species will face conditions beyond their historical and present ecological range.
Ecological niche modeling, using ESM and GRNN models, indicates that these species distribution will likely continue shifting poleward, reducing foraminiferal diversity in tropical and subtropical regions. Shifting alone may be insufficient for those species to cope with anthropic changes.
Recordings
You can (re-)watch all the speeches on our Youtube channel.
[#4 DIVERS] From reproductive strategies to species diversity: how evolution of breeding systems and associated traits shapes plant species diversity?
In November 2024, Sylvain Glémin (ECOBIO, Rennes, France) and Jos Käfer (ISEM, Montpellier, France) presented the results of the DIVERS group.
Abstract
Angiosperms (flowering plants) present an exceptional diversity of breeding systems, with variation both in gender distribution within and among individuals (from hermaphroditism to separate sexes) and in mating patterns (from strict outcrossing to predominant selfing). Breeding systems were shown to affect species diversification and to be associated with other life-history and ecological traits. Consequently, these systems could have been an important determinant of the observed species diversity in flowering plants.
The DIVERS project aimed to explore the hypothesis that the combination of traits associated with breeding systems could be a key factor in understanding evolutionary success and plant species diversity. This project sought to define integrated evolutionary strategies among these traits and to investigate how these strategies could shape the diversification process in flowering plants. This approach helped identify key components that could explain why some groups of flowering plants are more diverse than others and how combinations of traits could influence invasiveness and extinction risks.
Abstract
Angiosperms (flowering plants) present an exceptional diversity of breeding systems, with variation both in gender distribution within and among individuals (from hermaphroditism to separate sexes) and in mating patterns (from strict outcrossing to predominant selfing). Breeding systems were shown to affect species diversification and to be associated with other life-history and ecological traits. Consequently, these systems could have been an important determinant of the observed species diversity in flowering plants.
The DIVERS project aimed to explore the hypothesis that the combination of traits associated with breeding systems could be a key factor in understanding evolutionary success and plant species diversity. This project sought to define integrated evolutionary strategies among these traits and to investigate how these strategies could shape the diversification process in flowering plants. This approach helped identify key components that could explain why some groups of flowering plants are more diverse than others and how combinations of traits could influence invasiveness and extinction risks.
[#3 FREE 1] Functional rarity: from detection to conservation
In October 2024, Cyrille Violle (CEFE-CNRS, Montpellier, France) presented the results of the Free 1 group.
Abstract
Rarity has always fascinated conservation and evolutionary biologists with the goal to uncover species characteristics causing extinction risk. Recently, some results suggest that rare species may over-contribute to the diversity of traits within communities thus supporting irreplaceable roles while others show that rare species are functionally redundant with common species. Beyond the rarity of species, the rarity of functions played by species, coined as functional rarity, is thus key to understand the impact of biodiversity decline on ecosystem functioning. However, functional rarity still lacks a clear definition and a quantitative framework while its emergence and maintenance within communities is largely unknown.
As part of the FRB-CESAB FREE 1 working group, we have contributed to advance the concept of functional rarity and examine the causes and consequences of functional rarity from local to global scales. We showed that common assumptions notwithstanding, rare species can play unique and essential ecological roles, and that ecologically rare species are already more threatened by humans than ecologically common species and will be more impacted by future climate change. Finally, we highlighted that, in most taxonomic groups, hotspots of functional rarity differ from the areas where the most vulnerable species are found. This has major implications for species and ecosystem conservation where functional rarity appears to be an additional criterion to be considered urgently for the establishment of lists of so-called species at risk and for deciding on the location and size of areas to be protected.
Abstract
Rarity has always fascinated conservation and evolutionary biologists with the goal to uncover species characteristics causing extinction risk. Recently, some results suggest that rare species may over-contribute to the diversity of traits within communities thus supporting irreplaceable roles while others show that rare species are functionally redundant with common species. Beyond the rarity of species, the rarity of functions played by species, coined as functional rarity, is thus key to understand the impact of biodiversity decline on ecosystem functioning. However, functional rarity still lacks a clear definition and a quantitative framework while its emergence and maintenance within communities is largely unknown.
As part of the FRB-CESAB FREE 1 working group, we have contributed to advance the concept of functional rarity and examine the causes and consequences of functional rarity from local to global scales. We showed that common assumptions notwithstanding, rare species can play unique and essential ecological roles, and that ecologically rare species are already more threatened by humans than ecologically common species and will be more impacted by future climate change. Finally, we highlighted that, in most taxonomic groups, hotspots of functional rarity differ from the areas where the most vulnerable species are found. This has major implications for species and ecosystem conservation where functional rarity appears to be an additional criterion to be considered urgently for the establishment of lists of so-called species at risk and for deciding on the location and size of areas to be protected.
[#2 RED-BIO] Dynamic resource landscapes, ecological feedbacks and the emergence of meta-food webs
In September 2024, Isabelle Gounand (CNRS, iEES-Paris, France) presented the results of the RED-BIO group.
Abstract
Biodiversity and abiotic resource distribution are intrinsically intertwined. Resource distribution influences productivity and biodiversity, but animal movement also redistributes resources across landscapes. Metaecosystem theory integrates this dynamic feedback between biological communities and abiotic resources, but classically considers predefined fixed habitat patches. The assumption of fixed patches, however, does not match well with patterns observed in natural food webs where mobile organisms of different trophic levels forage across contrasting spatial scales.
RED-BIO synthesizes principles from meta-food web and metaecosystem theory to develop an integrated modelling framework of food web dynamics in spatially explicit landscapes. We began with a spatially explicit extension of a resource-plant-herbivore occupancy model, where habitat patches emerge from ecological feedbacks rather than being pre-defined and fixed. With this model, we investigate in which conditions dispersal and foraging scales of organisms drive the emergence of resource heterogeneity.
Future extension should include a body size-based version enabling to integrate food web complexity and evolutionary potential, in order to let the spatial and temporal heterogeneity emerge from both ecological interactions between animal movement and resource recycling, and eco-evolutionary feedbacks under global change.
Abstract
Biodiversity and abiotic resource distribution are intrinsically intertwined. Resource distribution influences productivity and biodiversity, but animal movement also redistributes resources across landscapes. Metaecosystem theory integrates this dynamic feedback between biological communities and abiotic resources, but classically considers predefined fixed habitat patches. The assumption of fixed patches, however, does not match well with patterns observed in natural food webs where mobile organisms of different trophic levels forage across contrasting spatial scales.
RED-BIO synthesizes principles from meta-food web and metaecosystem theory to develop an integrated modelling framework of food web dynamics in spatially explicit landscapes. We began with a spatially explicit extension of a resource-plant-herbivore occupancy model, where habitat patches emerge from ecological feedbacks rather than being pre-defined and fixed. With this model, we investigate in which conditions dispersal and foraging scales of organisms drive the emergence of resource heterogeneity.
Future extension should include a body size-based version enabling to integrate food web complexity and evolutionary potential, in order to let the spatial and temporal heterogeneity emerge from both ecological interactions between animal movement and resource recycling, and eco-evolutionary feedbacks under global change.
[#1 JUSTCONSERVATION] Towards ‘just conservation’: linking theories and practices of justice in biodiversity conservation
In June 2024, Brendan Coolsaet (FNRS & UCLouvain, Belgium) and Neil Dawson (University of East Anglia, Norway) presented the results of the JUSTCONSERVATION group.
Abstract
From 2018 to 2023, the JUSTCONSERVATION group has worked on reviewing the science on 50 years of biodiversity conservation. As conservation initiatives expand in response to biodiversity loss, there remains limited understanding about what forms of governance and roles for different actors produce the best social-ecological outcomes.
Drawing on evidence collected from 723 studies published in English-language peer-reviewed journals that describe and explore conservation efforts at a single site in 104 countries, we took stock of the geography of knowledge production in conservation science and studied its effect in upholding longstanding narratives about what should be conserved and by whom. We also explored relationships between conservation initiative types, governance types (including different levels of influence by Indigenous Peoples and local communities), and reported social and ecological outcomes.
Findings reveal that positive ecological and social outcomes are strongly associated with higher levels of influence of Indigenous Peoples and local communities and their institutions, implying equity in conservation practice should be advanced not only for moral reasons but because it can also enhance conservation effectiveness.
Abstract
From 2018 to 2023, the JUSTCONSERVATION group has worked on reviewing the science on 50 years of biodiversity conservation. As conservation initiatives expand in response to biodiversity loss, there remains limited understanding about what forms of governance and roles for different actors produce the best social-ecological outcomes.
Drawing on evidence collected from 723 studies published in English-language peer-reviewed journals that describe and explore conservation efforts at a single site in 104 countries, we took stock of the geography of knowledge production in conservation science and studied its effect in upholding longstanding narratives about what should be conserved and by whom. We also explored relationships between conservation initiative types, governance types (including different levels of influence by Indigenous Peoples and local communities), and reported social and ecological outcomes.
Findings reveal that positive ecological and social outcomes are strongly associated with higher levels of influence of Indigenous Peoples and local communities and their institutions, implying equity in conservation practice should be advanced not only for moral reasons but because it can also enhance conservation effectiveness.