Compositional changes in bee and wasp communities along Neotropical mountain altitudinal gradient.

Climate conditions tend to differ along an altitudinal gradient, resulting in some species groups' patterns of lower species richness with increasing altitude. While this pattern is well understood for tropical mountains, studies investigating possible determinants of variation in beta-diversity at its different altitudes are scarce. We sampled bee and wasp communities (Hymenoptera: Aculeata) along an altitudinal gradient (1,000-2,000 m.a.s.l.) in a tropical mountainous region of Brazil. Trap nests and Moericke traps were established at six sampling points, with 200 m difference in altitude between each point. We obtained average climate data (1970-2000) from Worldclim v2 for altitudes at each sampling site. Nest traps captured 17 bee and wasp species from six families, and Moericke traps captured 124 morphospecies from 13 families. We found a negative correlation between altitude and species richness and abundance. Temperature, precipitation, water vapor pressure, and wind speed influenced species richness and abundance, and were correlated with altitude. ß-diversity was primarily determined by species turnover as opposed to nestedness, and Aculeate community similarity was higher for more similar altitudinal ranges. Moericke traps seem to be more efficient for altitudinal surveys compared to nest traps. We found high occurrence of singleton and doubleton species at all altitudes, highlighting the need for long-term studies to efficiently assess hymenopteran diversity in these environments.

Facilitation as Attenuating of Environmental Stress among Structured Microbial Populations.

There is currently an intense debate in microbial societies on whether evolution in complex communities is driven by competition or cooperation. Since Darwin, competition for scarce food resources has been considered the main ecological interaction shaping population dynamics and community structure both in vivo and in vitro. However, facilitation may be widespread across several animal and plant species. This could also be true in microbial strains growing under environmental stress. Pure and mixed strains of Serratia marcescens and Candida rugosa were grown in mineral culture media containing phenol. Growth rates were estimated as the angular coefficients computed from linearized growth curves. Fitness index was estimated as the quotient between growth rates computed for lineages grown in isolation and in mixed cultures. The growth rates were significantly higher in associated cultures than in pure cultures and fitness index was greater than 1 for both microbial species showing that the interaction between Serratia marcescens and Candida rugosa yielded more efficient phenol utilization by both lineages. This result corroborates the hypothesis that facilitation between microbial strains can increase their fitness and performance in environmental bioremediation.

Cave conservation priority index to adopt a rapid protection strategy: a case study in Brazilian Atlantic rain forest.

Cave environments are characterized by possessing specialized fauna living in high environmental stability with limited food conditions. These fauna are highly vulnerable to impacts, because this condition can frequently be easily altered. Moreover, environmental determinants of the biodiversity patterns of caves remain poorly understood and protected. Therefore, the main goal of this work is to propose a cave conservation priority index (CCPi) for a rapid assessment for troglobiotic and troglophile protection. Furthermore, the troglobiotic diversity, distribution and threats have been mapped in the Brazilian Atlantic forest. To propose the CCPi, the human impacts and richness of troglobiotic and troglophile species of 100 caves were associated. Data related to troglomorphic/troglobiotic fauna from another 200 caves were used to map the troglobiotic diversity and distribution. The CCPi reveals extremely high conservation priority for 15% of the caves, high for 36% and average for 46% of the caves. Fourteen caves with extremely high priorities should have urgent conservation and management actions. The geographical distribution of the 221 known troglobiotic/troglomorphic species allowed us to select 19 karst areas that need conservation actions. Seven areas were considered to have urgent priority for conservation actions. The two richest areas correspond to the "iron quadrangle" with iron ore caves (67 spp.) and the "Açungui limestone group" (56 spp.). Both areas have several caves and are important aquifers. The use of the CCPi can prevent future losses because it helps assessors to select caves with priorities for conservation which should receive emergency attention in relation to protection, management and conservation actions.

How climate change can affect the distribution range and conservation status of an endemic bird from the highlands of eastern Brazil: the case of the Gray-backed Tachuri, Polystictus superciliaris (Aves, Tyrannidae) / Como as mudanças climáticas podem afetar a área de distribuição e o status de conservação de uma ave endêmica das montanhas do leste do Brazil: o caso do papa-moscas-de-costas-cinzentas, Polystictus superciliaris (Aves, Tyrannidae)

The Gray-backed Tachuri (Polystictus superciliaris) is a Tyrannidae restricted to eastern Brazilian highlands. Its population and range are still thought to be declining mainly due to habitat loss, caused by land use. We evaluated the impacts on its range (increase or decrease, displacement in latitude and altitude), considering possible effects caused by inappropriate land use and climatic changes. For this purpose, we modeled its current range and estimated its overlap between the predicted area and future scenarios. We also analyzed the efficiency of the Brazilian reserves to the species’ protection. The range established by the Maxent model was 76.1% lower than that available in the literature and presented a decrease in the future. Range contraction for the periods under consideration ranged from 22.5% to 77.3%. The distribution center shifts to the southwest (from 102.5 km to 275.4 km) and to higher elevations (1,102 m to 1,428 m). From the predicted range, 20% are under some kind of human occupation. The Brazilian reserves partially protect the species, with only 12% of its range, from the 44.2% expected. Based on these predictions, and depending on the species’ dispersal ability and adaptation, it may become vulnerable in the period of 2080. This study demonstrates that the most important areas for maintaining populations of P. superciliaris now and in the future are those located in the ‘Iron Quadrangle’, especially the Serra da Gandarela, where it was partially protected by the recently decreed Gandarela National Park. This region should receive special attention because it is strongly threatened by iron mining in areas relevant for conservation located outside this reserve.

O papa-moscas-de-costas-cinzentas (Polystictus superciliaris) é uma espécie de Tyrannidae endêmica dos topos de montanha do leste do Brasil. Sua população e área de distribuição estão em declínio principalmente devido è perda de habitat causada pelo uso inadequado da terra. Nós avaliamos os impactos sobre sua distribuição (aumento ou diminuição, deslocamento em latitude e altitude), considerando os possíveis efeitos causados pelo uso do solo e pelas mudanças climáticas. Para esse propósito, modelamos a distribuição atual e avaliamos a sobreposição entre a área predita e os cenários futuros. Também avaliamos a eficiência das Unidades de Conservação brasileiras para a proteção da espécie. A área de distribuição estimada por meio do programa Maxent foi 79,1% menor que a área encontrada na literatura, apresentando uma tendência a diminuição no futuro. Foi projetada uma contração de 22,5% a 77,3% da área de distribuição atual para o futuro. O centro da área de distribuição deslocou-se para o sudeste (de 102,5 a 275,4 km) e para áreas com alta elevação (1.102 m a 1.428 m). Da área projetada, 20% encontra-se sob algum tipo de ocupação humana. As Unidades de Conservação brasileiras protegem parcialmente a espécie, com somente 12% de sua distribuição quando o esperado seriam 44,2%. Baseado nas projeções e, dependendo das habilidades de dispersão e adaptação da espécie, ela pode se tornar vulnerável no período de 2080. Este estudo demonstrou que as áreas mais importantes para a manutenção de P. superciliaris na atualidade e em períodos futuros situam-se no Quadrilátero Ferrífero, especialmente na Serra da Gandarela, onde parte foi recentemente decretada como Parque Nacional da Gandarela. Essa região deve receber atenção especial por ser altamente ameaçada pela exploração do minério de Ferro e por áreas relevantes continuarem desprotegidas fora da abrangência do novo Parque.

Filopatria em abelha solitária Diadasina distincta / Philopatry in the neotropical ground-nesting solitary digger bee, Diadasina distincta [Holmberg, 1903] [Hymenoptera: Apidae] at a nesting site in southeastern Brazil

No presente trabalho apresentamos evidências de comportamento filopátrico na abelha solitária Diadasina distincta. Esta abelha nidifica em grandes agregações construídas no solo que chegam a ter até 2000 ninhos. Foram marcadas, em 1994 e 1995, 200 fêmeas e as distâncias entre o local de nascimento e o de construção dos ninhos foram medidas. Durante os dois anos de estudo a maioria das fêmeas nidificou entre 0.0 e 0.5 metros do ninho natal. A densidade de ninhos foi associada com a composição do solo, de forma que solos duros com altas porcentagens de areia foram preferidos em detrimento de solos mais úmidos com altas porcentagens de argila. Desta forma, as maiores densidades de ninhos foram verificadas em solos arenosos. Verificamos que o comportamento filopátrico se deve muito mais às condições do solo nas proximidades do ninho de nascimento do que à proximidade do alimento [AU]