Many species of palm produce chambers called domatia that are used by ants as nesting spaces. However, the ecological nature of this association is not well understood, and the information on palm–ant interactions is primarily anecdotal. Here, we conducted a field study in the secondary forest of the Danum Valley Conservation Area, Malaysian Borneo, on 41 individuals of the rattan Korthalsia furtadoana. All studied plants showed signs of a past or present partnership with domatia-nesting ants, as indicated by entry holes in domatia. In 14 plants, our physical disturbance of a stem provoked the appearance of patrolling ants of Camponotus sp. We compared the leaf conditions of rattans with and without patrolling ants, testing whether the presence of ants is linked to improved leaf health. The leaflets of plants with patrolling ants were significantly less physically damaged and less covered by epiphylls. On average, 19% of the leaflets of plants with patrolling ants were damaged (52% in plants without patrolling ants), and the epiphyll cover of their leaflets was 0.2 on our scale of 0–4 (1.3 in plants without patrolling ants). Our results suggest that this poorly studied plant–ant association has a mutualistic character. It seems that the ants take advantage of the nesting space created by the plant partner, while the plants gain protection for their photosynthetic apparatus against herbivores and epiphylls.

We investigated the effects of host tree on epiphyte diversity, controlling for microclimate. We measured the light profiles of the lower trunks of 20 individuals, each from three host groups (tree ferns, dicots, palms) occupying the understorey in a tropical montane forest in Panama. The per cent cover and species richness of vascular and non-vascular epiphytes were surveyed on the lower trunks of each understorey host. Light varied considerably between trees (5–21% total transmitted light) but mean light level did not vary between types of host. Light was not significant as a covariate with host in any model. Tree ferns had higher covers than dicots and palms of filmy ferns (15%, 0.02% and 0.2%), other ferns (7%, 0% and 0.5%) and other vascular epiphytes (16%, 3% and 3.4%), and greater species richness of vascular epiphytes (filmy ferns: 3, 0.4 and 0.5; other ferns: 2, 0.2 and 0; other vascular: 7, 2 and 2). Dicots had a higher cover of liverworts (53%) than palms (18%) and tree ferns (27%). Palms and tree ferns were the compositional extremes. We conclude that the differences in species composition and cover between the three host groups relate better to physical differences between hosts than differences in light climate.

Palms are important components of tropical forest plant communities, due both to their abundance (Henderson et al. 2000) and to the network of interactions with their pollinators and dispersers (Henderson 2002, Zona & Henderson 1989). Forest fragmentation alters the biotic and abiotic conditions of habitats (Ewers & Didham 2006, Fahrig 2003) and it has been observed that Attalea palms increase their densities in disturbed sites (Aguiar & Tabarelli 2009, Andreazzi et al. 2012, Lorenzi et al. 2004). Increased light availability (Salm 2005, Souza & Martins 2004), changes in seed dispersal and predation patterns (Andreazzi et al. 2012, Pimentel & Tabarelli 2004, Wright et al. 2000), and ability to recover after disturbance (Souza & Martins 2004) are among the main mechanisms that have been proposed to explain enhanced palm densities. However, how altered conditions following disturbances influence the dynamics of flower and fruit production is still little understood.

Wild populations of a small neotropical primate, Geoffroy's tamarin (Saguinus geoffroyi), were studied through 30-s instantaneous observational sampling to identify different canopy habitats used by this tamarin. Tree and shrub canopies were sampled in randomly selected plots and in nearby plots that tamarins were observed to use in the forests of Agua Clara, Panama (28 d, 59 100-m2 plots, 32.25 h of tamarin observations, 27 tamarins in total), and in the nearby forests of Barro Colorado Island (49 d, 29 100-m2 plots, 29.6 h of tamarin observations, 14 tamarins in total). Light penetration through the canopy, ambient temperature and humidity, presence of other primates, stem diameters, plant life-forms, distribution of woody flora, abundance of fleshy fruits and arthropods typically consumed by tamarins and abundance of thorny vegetation and biting arthropods in plots used by tamarins were compared with control plots. Habitats used by tamarins had significantly shorter distances between adjacent tree canopies and between canopies and the ground. There was a random distribution of large insects and fleshy fruits that tamarins are known to eat. Habitat selection by tamarins may not be influenced by spiny vegetation, but tamarins may avoid areas with abundant hooked thorns and blood-sucking arthropods. Mobility along runways in various tiers of a rain-forest canopy may be of primary importance, with local abundance of food being a secondary consideration in habitat selection by this small primate.

Long-term growth rates of 32 palms (Prestoea montana) were studied using height and diameter measurements taken four times between 1946 and 1982. All leaf scars were counted to estimate leaf production rate, and the distance between scars was measured to establish relationships between leaf production and height growth. Height and diameter growth and leaf production of these palms were not constant during this 36-year period. A greater distance between leaf scars was indicative of rapid height growth but not of high leaf production rate. Dominant palms always grew fast (> 20 cm/yr) in height when they were small, but height growth slowed down when they reached the canopy. Small palms with slow height growth remained suppressed and lost the capacity to grow rapidly in height as adults. Diameter growth decreased with age from 0.07 cm/yr (SE = 0.02) between 1946–51 to 0.01 cm/yr (SE = 0.003) between 1951–82. Annual leaf production averaged 4 leaves/yr over the 36 years of study, was significantly different (P = 0.001) between 1946–51 (5.6 leaves/yr) and 1951–82 (3.8 leaves/yr), and was 4.6 leaves/yr for palms that grew >5 m since 1946 and 3.7 leaves/yr for those that remained suppressed. The best estimate for the mean age of all palms was 61.1 yr (SE = 2.4), obtained from long-term population leaf production rates.

Diversity is positively correlated with water availability at global, continental and regional scales. With the objective of better understanding the mechanisms that drive these relationships, we investigated the degree to which variation in water availability affects the performance (recruitment, growth and survival) of juvenile trees. Precipitation was supplemented throughout two dry seasons in a seasonal moist forest in south-eastern Peru. Supplementing precipitation by 160 mm mo−1, we increased soil moisture by 17%. To generate seedling communities of known species composition, we sowed 3840 seeds of 12 species. We monitored the fates of the 554 seedlings recruited from the sown seeds, as well as 1856 older non-sown seedlings (10 cm ≤ height < 50 cm), and 2353 saplings (> 1 m tall). Watering significantly enhanced young seedling growth and survival, increasing stem density and diversity. Watering diminished the recruitment of species associated with upland forests, but increased the survival of both upland- and lowland-associated species. Though supplemental watering increased the growth of older seedlings, their density and diversity were unaffected. Sapling performance was insensitive to watering. We infer that variation in dry-season water availability may affect seedling community structure by differentially affecting recruitment and increasing overall survival. These results suggest that differential seedling recruitment and survival may contribute to the observed relationships between water availability, habitat associations and patterns of tree species richness.

The conservation status of 134 species, subspecies and varieties of West Indian palms (Arecaceae) is assessed and reviewed, based on field studies and current literature. We find that 90% of the palm taxa of the West Indies are endemic. Using the IUCN Red List categories one species is categorized as Extinct, 11 taxa as Critically Endangered, 19 as Endangered, and 21 as Vulnerable. Fifty-seven taxa are classified as Least Concern. Twenty-five taxa are Data Deficient, an indication that additional field studies are urgently needed. The 11 Critically Endangered taxa warrant immediate conservation action; some are currently the subject of ex situ and in situ conservation projects in the region’s botanical gardens. We recommend that preliminary conservation assessments be made of the 25 Data Deficient taxa so that conservation measures can be implemented for those facing imminent threats.

Plants often modify microsite conditions important for seedling establishment. In tropical moist forest, advance regeneration in the form of shade-suppressed seedlings is a major component of regrowth in new gaps. Tree seedlings may be filtered by the composition and structure of the forest understorey. In a lowland forest in Central Panama, we examined light availability, litter accumulation and the seedling community (abundance, diversity and composition) under and away from the canopies of a common subcanopy, clonal palm, Oenocarpus mapora, and tested whether seedling abundance varies as a function of changes in understorey light conditions and leaf litter depth. We found evidence that leaf litter was five times deeper and light availability 27% lower under O. mapora canopy than where it was absent. The probability of finding a seedling in plots under O. mapora canopies was 33% lower than in plots without the palm. Plots under O. mapora canopies also had 49% fewer species of seedlings and those seedlings came from significantly larger seeds than seedlings in plots not under the palm. Overall, seedling density was positively correlated with light availability and negatively correlated with leaf litter depth. A transplant experiment confirmed that for at least one large-seeded species of dicot, seedlings are negatively affected by the reduction in light availability and increase in leaf litter. Under O. mapora, seedlings of Gustavia superba (Lecythidaceae) had lower survivorship and biomass accumulation than away from the palm. Thus, site conditions produced by large, clonal, multi-layered palms such as O. mapora may reduce establishment of small-seeded and shade-intolerant species, potentially affecting species composition in the understorey seedling pool.

The conservation status of 23 Hawaiian endemic palms, Pritchardia spp., is reviewed. Field survey reports, recovery plans, herbaria holdings and observations have been utilized to assess each taxon's current range and status. Eleven species are categorized as Critically Endangered, nine Endangered, two Vulnerable and one as Data Deficient when subject to the IUCN Red List criteria. Conservation management options are discussed. A large proportion of this genus is on the verge of extinction and will continue to decline in the wild without active conservation management. Recommendations involving long-term management include maintaining and protecting the existing wild populations, establishment of effective ex situ populations, reintroduction into the wild, and the establishment of procedures to deal with invasive plants and animals.

Patterns of species composition in a neotropical termite assemblage were studied in relation to early effects of forest fragmentation as well as other sources of environmental and spatial heterogeneity. Termite diversity surveys were carried out at three mainland forest sites, and 10 islands of varying size, in an area of lowland tropical forest that had been flooded 4 y earlier, during the creation of the Petit Saut hydroelectric project in French Guiana. The ‘ghost forest’ of dead emergent trees in the flooded zone was also studied for its influence on island termite assemblages. Results suggested that the effects of forest fragmentation upon the total assemblage, and upon soil-feeders in particular, were subordinate to the influence of forest understorey palm density, and the closely associated gradients of soil humus depth and soil pH. Moreover, gradients for these three variables were uncorrelated with forest fragmentation and probably reflected spatial environmental heterogeneity pre-dating inundation events. Nevertheless, factors associated with forest fragmentation appeared to have had a significant effect on changes in termite species composition across the study site, primarily in structuring the wood- and leaf-litter-feeder assemblage. Effects upon the latter were not apparently a result of influx of species from the ghost forest. Purely spatial variation also influenced β-diversity changes in species composition across the site. In conclusion, the effects of forest fragmentation upon termites appear to have been relatively mild compared with other faunal groups, 4 y after flooding. Nevertheless, we predict that the effects of fragmentation on termite assemblages will ultimately be negative. This study also points to the importance of Amazonian understorey palms in structuring a tropical forest termite assemblage.

The Amazonian rain forests form one of the largest areas of continuous forest in the world, and they harbour a substantial part of the world's biodiversity (World Conservation Monitoring Centre 1992). The extravagant species richness of Amazonia makes collecting information on species distribution patterns there a formidable challenge. Relatively few studies have been able to provide data that cover both a large enough number of species and wide enough geographical areas to allow relevant biogeographical and ecological generalizations (such studies concerning plants include Balslev 1988, de Oliveira & Daly 1999, Pitman et al. 1999, Prance 1973, ter Steege et al. 2000, Terborgh & Andresen 1998, Tuomisto & Poulsen 1996). The scarcity of field observations is undoubtedly one of the reasons why very different ideas exist about the mechanisms that control plant distributions and patterns of species richness in Amazonia (Balslev 1988, Condit 1996, Gentry 1988, Nelson et al 1990, Pitman et al. 1999, Prance 1973, 1982; ter Steege et al. 2000, Tuomisto et al. 1995).

Infestation rates by palm bruchid beetles (Bruchidae: Pachymerini) on Attalea palm seeds are so high that most endocarps remaining near parent trees contain larvae rather than endosperm a few months after the peak fruiting season. Vertebrates feeding on palm endocarp contents may therefore be feeding on animal rather than plant matter, and the timing of use of endocarps may be influenced by the presence of larvae rather than by background fruit availability. On Maracá Island Ecological Reserve, Roraima State, Brazil, white-lipped peccaries (Tayassu pecari), agoutis (Dasyprocta leporina) and squirrels (Sciurus igniventris) all fed on bruchid beetle larvae from Attalea maripa palm endocarps. Squirrels fed on both larvae and endosperm year-round in all habitat types; agoutis fed on both larvae and seeds only at times and at sites where alternate foods were not available; and white-lipped peccaries fed almost exclusively on bruchid larvae in high-palm-density habitats. Differences in timing and location of endocarp use by these species may provide an index of mammal community dynamics in neotropical forests.

The reproductive ecology of piassava palm (Attalea funifera Mart.) was investigated for 19 months in the Atlantic forests of eastern Brazil. Its breeding biology is characterized by the production of functionally female, male and bisexual inflorescences. Staminate sterility is positively correlated with number of pistillate flowers. Staminate and pistillate flowers are receptive at anthesis. Bagging tests for apomixis were negative. Although geitonogamy can occasionally occur, outcrossing predominates. Pollen is relatively dry, but wind pollination is not a significant factor in cross pollination. Although inflorescences are visited by large numbers of insects, pollination is effected mainly by small sap beetles (Mystrops sp.) and weevils (Phyllotrox tatianae), which feed and breed in fertile staminate flowers. Pistillate flowers, which offer no reward to pollinators, appear to attract insect visitors by olfactory and visual imitation of staminate flowers, that is, via Bakerian mimicry. Flower production, fruit maturation, leaf production and leaf abscission occur continuously throughout the year. Flowering exhibits a distinct peak during the warmest months (Dec–Apr). Given its ubiquity throughout the region, A. funifera may well serve as a flowering and fruiting keystone species.

Abstract The conservation status of the five genera and 11 species of palm endemic to the Mascarene Islands (Mauritius, La Réunion and Rodriques) are reviewed. All species are threatened with extinction; nine taxa are classified as Critically Endangered and four as Endangered on the 2000 IUCN Red List. Two taxa survive as single wild specimens (Hyophorbe amaricaulis and Dictyosperma album var. conjugatum); an additional seven taxa have wild populations of 100 or fewer. Although the historical phase of large-scale forest clearance has passed, the remaining palm populations in the Mascarenes are under threat from the effects of population fragmentation, invasive plants and animals, and high levels of seed predation that prevent natural regeneration. The advantages of in situ management for the recovery of these palm populations are discussed. Without a long-term conservation programme, utilising both in situ and ex situ management, extinction of wild populations will occur.

Tapirs (Tapiridae) are the last representatives of the Pleistocene megafauna of South and Central America. How they affect the ecology of plants was examined by studying the diversity, abundance, and condition of seeds defecated by the lowland tapir (Tapirus terrestris) in Amazonian Brazil. Additionally, the spatio-temporal pattern of the seed-rain and seed-shadows generated by tapirs was recorded. Three hundred and fifty-six tapir faeces were examined. Eleven per cent were found in water (n = 41), while 88% were located on dry land (n = 315). Of those found on dry land, 84% were located at sites that flood seasonally, while 14% of the total were encountered at forest sites that do not flood. In 127 faeces checked in the laboratory over 12 906 seeds of at least 39 species were found. Seed viability ranged from 65% for Maximiliana maripa to 98% for Enterolobium schomburgkii. Of nine seed species planted in the laboratory, seven germinated within 4 wk, with one species achieving an 89% germination rate. For many species recruitment to the seedling stage was also high under natural conditions, with 13 plant species occurring as seedlings in older faeces. Tapir generated seed-rain occurred throughout the year, with seeds defecated in all months. Two temporal patterns in species seed rain occurred: (1) contiguous monthly occurrence with peaks in abundance, and (2) discontinuous occurrence (time clumped) with small (a few months) to large (many months to more than a year) temporal gaps. The highest diversity of seeds appeared in April, at the end of the dry season. As the last of the Pleistocene megafauna of the region, tapirs may have particular importance as dispersers of large seeds and generators of unique seed dispersion patterns.

An evaluation of whether large arborescent palms depend on large treefall gaps for recruitment to the adult stage is reported. Specifically three hypotheses were tested: (1) The light requirement of juveniles of tall arborescent palms increases as they grow in size. (2) Tall arborescent palms depend on gaps over 0.10 ha for growth and survival to maturity, due to high light requirements during the stem height growth phase. (3) Stilt-rooted palms are not dependent on gaps for juvenile height growth. The hypotheses were evaluated using data on size and crown position of individuals of tall arborescent palm species as well as data on the forest-phase in which each individual grew. The study site was a 50-ha plot in old-growth rain forest in Amazonian Ecuador. The first hypothesis was accepted for the two most common species, Iriartea deltoidea and Oenocarpus bataua, but tentatively rejected for the arborescent palm community as a whole. The second hypothesis was rejected for Iriartea and the community as a whole. Only Oenocarpus had strongly gap-dependent recruitment. The results for Iriartea and Oenocarpus were consistent with the third hypothesis.