Feather growth rate and mass in nearctic passerines with variablemigratory behavior and molt pattern

Bird species vary greatly in the duration of their annual complete feather molt. However, such variation is not well documented in birds from many biogeographic areas, which restricts our understanding of the diversification of molt strategies. Recent research has revealed that molt duration can be estimated in passerines from ptilochronology-based measurements of the growth rate of their tail feathers. We used this approach to explore how molt duration varied in 98 Nearctic species that have different migratory strategies and molt patterns. As previously documented for Palearctic species, migration was associated with a shortening of molt duration among species that molted during summer on their breeding range. However, molts of winter-molting migratory species were as long as those of summer-molting sedentary species, which suggests that winter molt also allows Nearctic migrants to avoid the temporal constraints experienced during summer. Our results also suggest that migratory species that undergo a stopover molt within the Mexican monsoon region have the shortest molt duration among all Nearctic passerines. Interestingly, and contrary to expectations from a potential tradeoff between molt duration and feather quality, observed variation in feather growth rate was positively correlated with differences in tail feather mass, which may be caused by differences among groups in the availability of resources for molting. We encourage the use of similar approaches to study the variation in molt duration in other geographic areas where knowledge of the evolution of molt is limited.

Urban infrastructure as materialized consensus

© 2016 Taylor & Francis Infrastructure that shapes and facilitates daily life, such as pathways, conduits and boundary walls, constitutes one of the most dynamic forms of architecture in both ancient and modern cities. Although infrastructure is conceived and designed with particular goals and capacities, its temporal and spatial scale means that it is a constant work in progress that engages numerous agents: civic authorities design and implement infrastructure; designated agencies maintain and repair infrastructure; and ordinary people utilize, modify, ignore or destroy it. Infrastructure can be thus analyzed as a materialization of ongoing communication, in which there are often conflicts among different constituents to achieve consensus. The linguistic concepts of expert language and turn-taking are utilized to assess three brief case studies: historical New Orleans; a multipurpose micro-park in Vienna, Austria; and the archaeological city of Sisupalgarh, India

Induction of mammary fibroadenomas in rats by adenovirus type 9

After inoculation of adenovirus type 9 into newborn Wistar/Furth rats, seven out of seven females developed one or several mammary fibroadenomas within 14–25 weeks after virus inoculation. No tumours were observed in male rats inoculated with the same virus or in untreated controls. Neonatal inoculations of adenovirus type 5, produced on the same HeLa cells, gave negative results in both sexes. The results indicate that benign mammary tumours can be induced in rats by a virus and that mammary fibroadenomas are induced by adenovirus type 9, previously known to be capable of transforming cells in vitro but not of inducing tumours in vivo