PhD in Sustainable development and cooperation

Contacts

Supervisor

Phd thesis

Ants are ecosystem engineers and bioindicators that can be directly or indirectly impacted by human activities in agricultural landscapes. Their successful social organisation relies on several communication cues that enable the colony's proper functioning and the ability to discriminate between nestmates and strangers. The ant recognition system is based on mixtures of Cuticular HydroCarbons (CHCs) which form a chemical signature peculiar to each colony. Multiple factors influence the chemical profiles (e.g. climatic conditions), and I hypothesise that the variation of CHCs could also be an outcome of the association between ants and their microbiota.

My PhD project aims to understand the ant-microorganism relationship and how biotic and abiotic factors in agricultural environments could affect this association.

Specifically, I will assess:

- the role of microbiota on ant social behaviour and recognition abilities;

- how human activities alter the soil characteristics in agricultural environments.

I will then evaluate if human activities influence the ant behaviour directly by altering the soil characteristic or indirectly by modulating the microbial community associated with ants.

Ant nests and soil will be sampled in vineyards with different management (organic/ traditional) and in natural areas. A multidisciplinary approach, combining pedology, edaphology, metabarcoding, ethological assays and gas chromatography techniques, will be used to tackle my research questions.

The artificial modification of the ant microbiota and the following analysis of their CHC profiles will shed light on the potential contribution of microorganisms in developing the colony odour. If the microbiota plays a role in a fundamental mechanism fostering the colony structure, microorganisms should be regarded as a further pressure shaping the evolution of insect eusociality. The knowledge of how human activities, through the modification of the environment, could affect the biology of an essential component of the ecosystem is crucial to suggesting sustainable exploitation of our agricultural ecosystems.

Research activities

Poster presentation: “Microbial communities of Maculinea larvae and their Myrmica host ants” at the XIX IUSSI International Congress 2022 (International Union for the Study of Social Insects), held in San Diego, California (July 3-7, 2022).

Oral presentation: “Description et comparaison des profils d’hydrocarbures cuticulaires de deux espèces de fourmis récoltées en Italie: Lasius alienus et Tetramorium caespitum” (Arthur Hais, Francesca Barbero, Luca P. Casacci, Patrizia d'Ettorre) at the 31st conference of the UIEIS-SF (French section of the International Union for the Study of Social Insects) held in Toulouse, France (28-30 august 2023).