Periodic Reporting for period 1 - UrbanCog (Animal Cognition in Urban Environments: The effect of diet and the gut microbiome)
Okres sprawozdawczy: 2023-01-01 do 2024-12-31
Natural habitats are disappearing at record speeds, and our world is becoming increasingly urbanised. Recently, researchers started exploring how cognitive abilities (the mechanisms by which animals acquire, process, store and act on information from the environment) may allow animals to adapt to urban environments. Many of these studies revealed cognitive differences between urban and non-urban dwelling animals and linked these to informational challenges related to the highly dynamic nature of urban environments. Here we hypothesized that urban diets also contribute to such cognitive differences. Although lab-based studies indeed showed important effects of diet on the development of cognition, this idea so far received little attention in the urban cognition literature. We addressed this important knowledge gap by combining theoretical frameworks and methodology from psychology, ecology, and microbial sciences. Specifically, we tested how high-fat high-sugar diets (as found in urban environments) shape cognition. Lab-based studies also showed that diet induced changes in the gut microbiota impacts cognition. Hence, we also tested how such high-fat high-sugar diets affect gut microbiota, and whether gut microbiota composition mediates the effect of diet on cognition. To do so, we used feral pigeons, a species that thrives in urban environments, and whose diet varies widely between urban and non-urban environments, as my model species. We collaborated with a pigeon breeder and racer to examine the relationship between diet, the gut microbiota and different aspects of pigeon’s learning to fly and navigate their environment.
We performed a long-term experiment tracking the development of racing pigeons over their first 9 months of life. The aim was to investigate the early-life effect of high-fat high-sugar diet on their gut microbiota and the cognition. We had two groups of pigeons which either had a high-fat high-sugar diet for four weeks once they became independent from their parents, or a control diet – which was based on the same mix of grains than the high-fat high-sugar diet, but without the added fat and sugar. We collected gut microbiota samples before and after the treatment, as well as every 4 weeks after the end of the treatment (up to 16 weeks after the treatment) to investigate long term effects of the diet. During this time, birds were first trained to fly and associate the loft with their home. Once they flew reliably around the loft, they were gradually released away from the loft and were trained to navigate their way back to the loft. We equipped pigeons with GPS trackers during every flight. We also collated data on the birds’ racing performance in their first racing seasons.
This work allowed me to learn multiple new skills in the field of microbial sciences and movement ecology, and collaborate with pigeon breeders and racers.
This work allowed me to learn multiple new skills in the field of microbial sciences and movement ecology, and collaborate with pigeon breeders and racers.
We found that diet had both a short-term and a long-term effect on the gut microbiota, with changes taking place 8 weeks after the end of the diet. We also found differences in flight patterns: birds which received the high-fat high-sugar diet when they were young spent more time flying earlier when they were training around the loft, but they were less coordinated than the birds that were raised on a control diet. When we trained birds to navigate back to the loft, we also found that the birds from the two treatments used different strategies: the birds from the high-fat high-sugar diet came back to the loft faster than the ones from the control diet, the latter being more explorative of their environment. Finally, we found no evidence of an effect of diet on the birds’ racing performance.