STRUCTURE OF THE SHRUB-ARBOREAL COMPONENT OF AN ATLANTIC FOREST FRAGMENT ON A HILLOCK IN THE CENTRAL LOWLAND OF RIO DE JANEIRO, BRAZIL

The present study describes and evaluates the horizontal and vertical structures of a lowland forest fragment on a hillock in the municipality of Silva Jardim, Rio de Janeiro State, Brazil (22 degrees 31`56 `` S and 42 degrees 20`46 `` W). Twenty plots (10x2m) totaling 0.5ha were laid out following the slope grade using DBH >= 5cm as the inclusion criterion. A total of 734 individuals were encountered, yielding a total density of 1468 ind./ha and a total basal area of 10783m(2). The richness values (129 species/41 families), Shannon-Wiener diversity (4.22) and equitability (0.87) indices indicated an accentuated floristic heterogeneity and low ecological dominance. Lauraceae, Myrtaceae, Fabaceae and Euphorbiaceae showed the greatest species richness, corroborating other studies that indicated these species as the most representative of Atlantic Forest areas in southeastern Brazil. The species with the greatest importance values (VI) were Aparisthmium cordatum, Guapira opposita, Lacistema pubescens, Xylopia sericea, Tapirira guianensis and Piptocarpha macropoda. The high diversity observed was influenced by earlier anthropogenic actions and by the current successional stage. The forest fragment studied demonstrated closer floristic similarity to areas inventoried in a close-by biological reserve than to fragments dispersed throughout the coastal plain. Similarities in soil type, degree of soil saturation and use-history of forest resources all support these relationships. The fragmented physiognomy of the central lowland in this region and the use-history of the landscape make these small remnant forest areas important in terms of establishing strategies for landscape restoration and species conservation.

Activity, movement and secretive behavior of a threatened arboreal folivore, the thin-spined porcupine, in the Atlantic forest of southern Bahia, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hylin a1, the first cytolytic peptide isolated from the arboreal South American frog Hypsiboas albopunctatus ('spotted treefrog')

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Morphological adaptations to arboreal habitats and heart position in species of the neotropical whipsnakes genus Chironius

The evolution of arboreality in snakes is accompanied by modifications that are remarkably similar across species. Gravity is one of the most important selective agents, and arboreal snakes present adaptations to circumvent the gradient of pressure, including modifications on heart position (HP) and body slenderness (BS). However, the degree to which different life-history traits influence the cardiovascular system of snakes remains unclear. Here, we used an ecological and a phylogenetic approach to explore the relationship between habitat, HP, BS, and heart size (HS) in five species of the neotropical whipsnakes genus Chironius that occupy terrestrial, semiarboreal, and arboreal habits. Our ecological comparison indicated that the arboreal species have the most posterior-positioned heart, the most slender body, and the smallest HS, whereas the terrestrial representative of the group exhibited the most anterior heart, the less flattened body, and the largest HS. After removing the phylogenetic effect, we found no difference in HP and BS between terrestrial and arboreal species. Habitat only differed when contrasting with HS. Body slenderness and HS were correlated with HP. Our results suggest that different restrictions, such as anatomical constraints, behavior, and phylogenetic inertia, may be important for the studied species. © 2013 The Royal Swedish Academy of Sciences.

Spatial-Temporal Variation in Orchid Bee Communities (Hymenoptera: Apidae) in Remnants of Arboreal Caatinga in the Chapada Diamantina Region, State of Bahia, Brazil

The spatial and temporal distribution of organisms is a fundamental aspect of biological communities. The present study focused on three remnants of arboreal Caatinga in northeastern Brazil between May, 2009 and April, 2010. A total of 627 euglossine males were captured in traps baited with artificial aromatic compounds. The specimens belonged to 14 species and four genera: Euglossa Latreille, Eulaema Lepeletier, Eufriesea Cockerell, and Exaerete Hoffmannsegg. Eulaema nigrita Lepeletier (41.6), Euglossa carolina Nem,sio (15.3%), Eulaema marcii Nem,sio (13.6%), and Euglossa melanotricha Moure (12.8%) were the most common species sampled. The distribution of collected specimens per fragment was as follows: BraA(0)na (280 ha)-259 individuals belonging to 14 species; Cambui (179 ha)-161 individuals from eight species; and Pindoba (100 ha)-207 individuals represented by seven species. BraA(0)na had the highest diversity (H'aEuro parts per thousand= 1.91) and estimated species richness. The largest fragment was the main source of the observed variation in species richness and abundance, indicating a non-random pattern of spatial distribution. The analysis of environmental factors indicated that seasonal variation in these factors was the principal determinant of species occurrence and abundance.

Activity, movement and secretive behavior of a threatened arboreal folivore, the thin-spined porcupine, in the Atlantic forest of southern Bahia, Brazil

Activity and behavior patterns are important components of a given species ecological strategy, as they have profound implications for its survival and reproduction. Here, we studied the activities, movements and secretive behavior of the thin-spined porcupine Chaetomys subspinosus (Rodentia: Erethizontidae), a threatened arboreal folivore in the Brazilian Atlantic rainforest. We aimed to ascertain the behavioral strategies used by this species as well as its responses to seasonal and daily climatic changes. Four radio-collared individuals were followed continuously for 72-h in the summer and winter, as well as during 146 half-night sessions conducted from April 2005 to September 2006 in forest remnants in southern Bahia. The thin-spined porcupines were nocturnally active (17:30-05:40 h), with peaks in activity and movement from 19:00 to 20:00 h and 03:00 to 04:00 h. Animals followed a circadian rhythm of activity during both the summer and winter. During the diel cycle, porcupines spent 74% of their time resting, 14% feeding, 11% traveling and 2% performing other activities. Distance traveled during the diel cycle averaged 277.5 +/- 117.9 m sd. The mean movement rate during the night was 21.6 +/- 30.1 m/h sd. No significant changes in activity budget or daily distance traveled were observed between seasons, most likely in response to the low fluctuations in climatic conditions and food availability throughout the year in the study region. However, rainfall reduced the time that the animals spent on feeding activities and explained day-to-day differences in activity budgets. We also provide details about intraspecific interactions and defecation behavior. Our observations confirmed that thin-spined porcupines, similar to other folivorous species, present low activity levels and short daily movements, and have adopted various cryptic habits, such as nocturnality, a solitary lifestyle, the tendency to leave offspring alone most of the time and defecation in concealed latrines.

(Table 1) Non-arboreal and arboreal pollen spectra at DSDP Holes 75-532 and 75-530A

Some samples from DSDP Holes 530A and 532 were analyzed for their fossil pollen content. The sites are located in the southeastern corner of the Angola Basin, about 200 km west of the present coastline. Fossil pollen assemblages of Holocene to Miocene age were compared with present-day pollen deposition in the arid Namib sand sea. The strong resemblance of all the pollen spectra indicates that very arid conditions existed in the coastal region of Namibia in Quaternary and Pliocene times. These data are in agreement with the late Miocene origin of the coastal aridity and with the conception that upwelling of cold water was responsible for these desert conditions.

Flying vs. climbing: Factors controlling arboreal seed removal in oak-beech forests

Nuts are heavy and nutritious seeds that need animals to be successfully dispersed. Most studies address nut removal by a single animal species once seeds fall onto the ground. However, nuts are also accessible before the seed drop and usually to a wide guild of seed foragers. This study examines the factorscontrollingarborealseedremoval in oak–beechforests within the whole guild of nut foragers. We found that seed-dispersing rodents (Apodemus sylvaticus) were the main acorn removers in the oaks (up to 3.75 m height), with a rapid seed encounter and a high removal rate. However, rodents did not climb the beech trees, probably due to their smoother bark in comparison to oak bark and/or the lower nutritional value of beechnuts with regard to acorns. Jays (Garrulus glandarius) were more abundant in oak stands (both dense and scattered) and clearly preferred acorns to beechnuts whereas nuthatches (Sitta europaea) were more abundant in beech stands and preferred beechnuts to acorns. Non-storing birds such as great tits (Parus major) also removed acorns and beechnuts, especially in the stands where oaks are dominant. Jays and rodents preferred sound seeds over insect-infested seeds but such a preference was not found for nuthatches. This study highlights that pure beech stands showed a reduced guild of arboreal nut foragers in comparison to oak stands. This different guild could probably affect the spatial patterns of seed dispersal, with a proportionally higher number of long dispersal events for acorns (mostly jay-dispersed) than for beechnuts (mostly nuthatch-dispersed). Long-distance dispersal of beechnuts (by jays) is determined by the presence of other preferred species (oaks) and their frequency of non-mast years. Seed location in different habitats strongly determines the contribution of different arboreal removers (including climbing rodents) and their removal speed, leading to a differential seed fate that will eventually affect tree regeneration. As nuthatches are sedentary birds, it is important to maintain old and dead trees where they can breed (crevices), forage (arthropods) and store seeds in order to favor beechnut dispersal and gene flow. By maintaining or favoring oak trees within beech stands we will ensure a wider guild of arboreal nut dispersers.

Regional vegetation changes in the tropical Andes expressed as arboreal pollen (AP%), standardised ordination scores (DCA z-scores), and aquatic vegetation ratios (D/SS); files used for plots

We compare eight pollen records reflecting climatic and environmental change from the tropical Andes. Our analysis focuses on the last 50 ka, with particular emphasis on the Pleistocene to Holocene transition. We explore ecological grouping and downcore ordination results as two approaches for extracting environmental variability from pollen records. We also use the records of aquatic and shoreline vegetation as markers for lake level fluctuations, and precipitation change. Our analysis focuses on the signature of millennial-scale variability in the tropical Andes, in particular, Heinrich stadials and Greenland interstadials. We identify rapid responses of the tropical vegetation to this climate variability, and relate differences between sites to moisture sources and site sensitivity.

Aeropalynology of Australian native arboreal species in Brisbane, Australia

The influence of meteorological parameters on airborne pollen of Australian native arboreal species was investigated in the sub-tropical city of Brisbane, Australia over the five-year period, June 1994–May 1999. Australian native arboreal pollen (ANAP), shed by taxa belonging to the families Cupressaceae, Casuarinaceae and Myrtaceae accounts for 18.4% of the total annual pollen count and is distributed in the atmosphere during the entire year with maximum loads restricted to the months May through November. Daily counts within the range 11–100 grains m–3 occurred over short intervals each year and were recorded on 100 days during the five-year sampling period. Total seasonal ANAP concentrations varied each year, with highest annual values measured for the family Cupressaceae, for which greater seasonal frequencies were shown to be related to pre-seasonal precipitation (r 2 = 0.76, p = 0.05). Seasonal start dates were near consistent for the Cupressaceae and Casuarinaceae. Myrtaceae start dates were variable and established to be directly related to lower average pre-seasonal maximum temperature (r 2 = 0.78, p = 0.04). Associations between daily ANAP loads and weather parameters showed that densities of airborne Cupressaceae and Casuarinaceae pollen were negatively correlated with maximum temperature (p < 0.0001), minimum temperature (p < 0.0001) and precipitation (p < 0.05), whereas associations with daily Myrtaceae pollen counts were not statistically significant. This is the first study to be conducted in Australia that has assessed the relationships between weather parameters and the airborne distribution of pollen emitted by Australian native arboreal species. Pollen shed by Australian native Cupressaceae, Casuarinaceae and Myrtaceae species are considered to be important aeroallergens overseas, however their significance as a sensitising source in Australia remains unclear and requires further investigation.

The status of hollow-bearing trees required for the conservation of arboreal marsupials in the dry sclerophyll forests of south-east Queensland, Australia

At 38 sites in the dry sclerophyll forests of south-east Queensland, Australia, hollow-bearing trees were studied to determine the effects of past forestry practices on their density, size and spatial distribution. The density of hollow-bearing trees was reduced at sites that had been altered by poisoning and ringbarking of unmerchantable trees. This was especially the case for living hollow-bearing trees that were now at densities too low to support the full range of arboreal marsupials. Although there are presently enough hollow-bearing stags (i.e., dead hollow-bearing trees) to provide additional denning and nesting opportunities, the standing life of these hollow-bearing stags is lower than the living counterparts which means denning and nesting sites may be limited in the near future. The mean diameter at breast height (DBH) of hollow-bearing stags was significantly less than that of living hollow-bearing trees. This indicated that many large hollow-bearing stags may have a shorter standing life than smaller hollow-bearing stags. Hollow-bearing trees appear to be randomly distributed throughout the forest in both silviculturally treated and untreated areas. This finding is at odds with the suggestion by some forest managers that hollow-bearing trees should have a clumped distribution in dry sclerophyll forests of south-east Queensland.

Mesostigmatid mites (Acari : Mesostigmata) on rainforest tree trunks: Arboreal specialists, but substrate generalists?

Predatory mites (Acari: Mesostigmata) on tree trunks without significant epiphytic growth in a subtropical rainforest in Eastern Australia were assessed for habitat specificity (i.e. whether they are tree trunk specialists or occupying other habitats) and the influence of host tree and bark structure on their abundance, species richness and species composition. The trunks of nine tree species from eight plant families representing smooth, intermediate and rough bark textures were sampled using a knockdown insecticide spray. In total, 12 species or morphospecies of Mesostigmata (excluding Uropodina sensu stricto) were collected, most of which are undescribed. Comparison with collections from other habitats indicates that epicorticolous Mesostigmata are mainly represented by suspended soil dwellers (six species), secondarily by generalists (four species) and a bark specialist (one species). A typical ground-dwelling species was also found but was represented only by a single individual. In terms of abundance, 50.5% of individuals were suspended soil dwellers, 40.7% bark specialists, and 8.3% generalists. Host species and bark roughness had no significant effect on abundance or species richness. Furthermore, there was no clear effect on species composition. The distribution of the most frequently encountered species suggests that most mesostigmatid mites living on bark use many or most rainforest tree species, independent of bark roughness. These findings support the hypothesis that some epicorticolous Mesostigmata use tree trunks as 'highways' for dispersing between habitat patches, while others use it as a permanent habitat.