Search results for "mutualism"

Tradeoffs in the evolution of plant farming by ants

2020

Diverse forms of cultivation have evolved across the tree of life. Efficient farming requires that the farmer deciphers and actively promotes conditions that increase crop yield. For plant cultivation, this can include evaluating tradeoffs among light, nutrients, and protection against herbivores. It is not understood if, or how, nonhuman farmers evaluate local conditions to increase payoffs. Here, we address this question using an obligate farming mutualism between the ant Philidris nagasau and epiphytic plants in the genus Squamellaria that are cultivated for their nesting sites and floral rewards. We focused on the ants' active fertilization of their crops and their protection against he…

Invasional meltdown via horizontal gene transfer of a European symbiosis island variant in North American nodule symbionts of Cytisus scoparius

2022

New data from sites in Spain, Sicily and North America establish that the spread of the European legume Cytisus scoparius (Scotch broom) across North America involved the concurrent invasion of a European mobile genetic element (symbiosis island [SI]) into North American Bradyrhizobium nodule bacteria. At four SI loci, bacteria from nine C. scoparius populations across the continent were all identical to haplotypes present in European Bradyrhizobium strains. At seven non-symbiotic (housekeeping) loci, these American C. scoparius bacteria grouped into eight diverse lineages related to, or in some cases identical to, symbionts from several native North American legumes. Inoculation experiment…

A Study of the Coevolution of Digital Organisms with an Evolutionary Cellular Automaton

2021

This article belongs to the Section Evolutionary Biology.

L'emigrazione dei santaninfesi in America e la storia delle derivate Società di Mutuo Soccorso

2010

Il radicalismo dell'emigrazione santaninfese attraverso la storia delle società di mutuo soccorso e del Galileo temple

Città, diritti e pratiche di mutualismo: riflessioni a partire dalle istanze comunitarie ai tempi della pandemia

2022

During the pandemic crisis, the “community” practices of mutualism have characterized the urban space by operating in a subsidiary, if not a substitute, manner with respect to public institutions. Their actions have been political in the sense in which Hannah Arendt defined this concept. Starting from a reflection on vulnerabilities, taking a case study as the object, and dialoguing with Orsetta Giolo’s essay, The rights against the city. Urban space, subjectivity and the public sphere, published in 2021, the potential and limits of these practices will be analyzed, along with their relationship with established power, with respect to the renewed tension between rights and territoriality, w…

Le rôle écologique des bonobos : service écologique de dispersion de graine en forêt du Congo

2012

Bonobos (Pan paniscus) are threatened with extinction. They are the largest primates, and the only apes (except human), of the southern bank of the Congo Basin. Along with chimpanzees, they are our closest living relatives and are studied by anthropologists to include/understand our hominid origins; but what about their functional role in the forest? Would their disappearance have serious consequences for forest ecology? Answering this question is the aim of this new project, with several years of observations of a free-ranging habituated group of bonobos on the LuiKotale research station (DR Congo). In this tropical rainforest, the very great majority of plants need animals to reproduce an…

Costs-benfits trade-off in the intercation between Medicago truncatula and Pseudomonas fluorescens C7R12 across atmospheric carbon dioxide modulation

2011

The interactions between plants and soil microorganisms are mainly based on trophic relationships. The compounds exchanged represent cost for the organism produces them but a benefit for the one who receive those compounds. A mutualistic relation leads to stability in the cost-benefit balance resulting from a co-evolution between the two organisms. The cost corresponding for the release of carbon compounds by the plant would be offset by benefits in return corresponding for the activities of microorganisms that use them. We tested by an experimental way the effect of CO2 concentration on the interaction between M. truncatula and the bacterium P. fluorescens C7R12. The results allowed a best…

Elucidating the population structure of the ubiquitous arbuscular mycorrhizal fungal species Rhizophagus irregularis: implications for fungal communi…

2012

The Largest Subunit of RNA Polymerase II as a New Marker Gene to Study Assemblages of Arbuscular Mycorrhizal Fungi in the Field

2014

Due to the potential of arbuscular mycorrhizal fungi (AMF, Glomeromycota) to improve plant growth and soil quality, the influence of agricultural practice on their diversity continues to be an important research question. Up to now studies of community diversity in AMF have exclusively been based on nuclear ribosomal gene regions, which in AMF show high intra-organism polymorphism, seriously complicating interpretation of these data. We designed specific PCR primers for 454 sequencing of a region of the largest subunit of RNA polymerase II gene, and established a new reference dataset comprising all major AMF lineages. This gene is known to be monomorphic within fungal isolates but shows an…

Microorganisms and Biotic Interactions

2014

SPE IPM; Most ecosystems are populated by a large number of diversified microorganisms, which interact with one another and form complex interaction networks. In addition, some of these microorganisms may colonize the surface or internal parts of plants and animals, thereby providing an additional level of interaction complexity. These microbial relations range from intraspecific to interspecific interactions, and from simple short-term interactions to intricate long-term ones. They have played a key role in the formation of plant and animal kingdoms, often resulting in coevolution; they control the size, activity level, and diversity patterns of microbial communities. Therefore, they modul…