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Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats and, potentially, to local extinctions. Understanding how multiple taxa respond to urbanisation globally is essential to promote and conserve biodiversity in cities and surrounding landscapes. Using a dataset with site-level occurrence and trait data of 5302 species from six terrestrial fauna taxonomic groups across 379 cities on 6 continents, we show that urbanisation produces taxon-specific changes in trait composition, with traits related to reproductive strategy consistently showing the strongest response. The effect of urbanisation on community trait composition is strongest at the largest spatial scale considered, and more closely linked to landscape composition (% urban) than arrangement (aggregation), although latitude and climatic variables remain a stronger influence. This study did not find evidence in support of a global urban taxa syndrome, but instead we suggest that there are four general urban trait syndromes, with resources associated with reproduction and diet likely to be driving patterns in traits associated with mobility and body size. Functional diversity measures showed a wide range of responses, leading to a shift in trait space that is most likely driven by the distribution and abundance of critical resources, and the urban trait syndrome displayed by individual species within a community. Further research is required to understand the interactions between the four general urban trait syndromes, resource distribution and abundance and changes in functional diversity of taxa at different spatial and temporal scales. Maximising opportunities to support species within taxa groups with different urban trait syndromes should be pivotal in conservation and management programmes within and among cities. This will reduce the likelihood of biotic homogenisation at the taxa level, and helps ensure that urban environments have the ecological capacity to respond to challenges such as climate change, further habitat fragmentation and loss, and other disruptions. These actions are critical if we are to reframe the role of cities in global biodiversity loss.

Anurans and birds rely on sound for a number of social behaviors. Species that use roadside habitats are exposed to traffic noise that can mask important social signals and directly affect the community diversity and composition. We evaluate the impact of traffic noise on anuran and bird species richness, species occurrence, and composition in Puerto Rico, where there is a high density of highways and cars that generate high levels of noise pollution. We compared paired forest sites near (100 m, n = 20, dB > 60) and far (>300 m, n = 20, dB 80 dB), which may allow them to tolerate high levels of anthropogenic noise.

Interactions between heterospecific species with similar sexual signals can lead to errors in mate attraction and species recognition. As a consequence sexual signals might diverge to reduce communication errors. Since high-density populations create more noise than low-density populations we hypothesize that individuals should suffer less acoustic interference from sympatric congeners with low-density populations than higher density populations of congeners. Even though species might be sympatric at multiple sites, only populations at sites with a relatively high abundance of both species should require one species to make vocal adjustments that minimize acoustic interference. To test this hypothesis we studied Eleutherodactylus coqui populations in the presence of relatively high numbers of E. portoricensis and in the presence of relatively low abundance of E. portoricensis. We found subtle differences in advertisement calls of E. coqui at locations where E. portoricensis had relatively high a...

The bird and amphibian communities of Puerto Rico have high levels of diversity and endemism. Although Puerto Rico has a very high density of roads and high levels of noise pollution, presently 40% of the island is covered in forest. I will address the following questions: Do high levels of anthropogenic noise change species composition of amphibians and birds? Are amphibians and birds modifying the time of calling and/or characteristics of their vocalization in response to anthropogenic noise? I collected sound recordings in two habitats. For recordings I used the automated recording devices developed by our research group. Each recording device was programmed to record for 7 consecutive days; 1 min every 20 min. Previous results showed that noise influences the bird community composition in secondary lowland forest sites, but not in karst forest. Another possibility is that bird and amphibian use other strategies to minimize the effect of noise. This can involve evolutionary changes in signal characteristics, as a long term adaptation or the species may be adjusting signal traits in response to variations in noise levels as a short term adaptation. I will answer these questions when I do analyzing all data.