Urban Identity and tourism:different looks, one single place

‘Urban identity’ is high on the policy agenda and pervades the discourse of the planning community on the value of historical city centres. Unfortunately, there seems to be, until today, no proposal in scholarly literature of any unified conceptual framework or any tools to make identity operational. ‘Tourism’ takes advantage of this process, by seeking the qualities of the place, its authenticity and its perceived uniqueness that is grounded on the physical features as well as on the presence of local communities – their way of living and investing in the place. The interdependence between identity as perceived by tourists (external observer) and the identity of the residents rooted in the relationship with the place (in-group) are key to addressing the identity of historic urban areas. These issues are addressed in the context of the growing attractiveness of Lisbon, Portugal, using a historic neighbourhood as a case study. The findings, which are on a set of interviews with different groups of users, showed the points of convergence and divergence between the different groups’ views of the neighbourhood’s identity. This actor-oriented approach is pivotal to understanding the process and to produce knowledge for informed action.

Identity of a Tilapia Pheromone Released by Dominant Males that Primes Females for Reproduction

Knowledge of the chemical identity and role of urinary pheromones in fish is scarce, yet it is necessary in order to understand the integration of multiple senses in adaptive responses and the evolution of chemical communication [1]. In nature, Mozambique tilapia (Oreochromis mossambicus) males form hierarchies, and females mate preferentially with dominant territorial males, which they visit in aggregations or leks [2]. Dominant males have thicker urinary bladder muscular walls than subordinates or females and store large volumes of urine, which they release at increased frequency in the presence of subordinate males or preovulatory, but not postspawned, females [3–5]. Females exposed to dominant-male urine augment their release of the oocyte maturation-inducing steroid 17α,20β-dihydroxypregn-4-en-3-one (17,20β-P) [6]. Here we isolate and identify a male Mozambique tilapia urinary sex pheromone as two epimeric (20α- and 20β-) pregnanetriol 3-glucuronates. We show that both males and females have high olfactory sensitivity to the two steroids, which cross-adapt upon stimulation. Females exposed to both steroids show a rapid, 10-fold increase in production of 17,20β-P. Thus, the identified urinary steroids prime the female endocrine system to accelerate oocyte maturation and possibly promote spawning synchrony. Tilapia are globally important as a food source but are also invasive species, with devastating impact on local freshwater ecosystems [7, 8]. Identifying the chemical cues that mediate reproduction may lead to the development of tools for population control [9–11].