Variability in fruit and seed morphology among and within populations of Plathymenia (Leguminosae-Mimosoideae) in areas of the Cerrado, the Atlantic forest, and transitional sites

Plathymenia reticulata is a tree species that occurs in two different Brazilian biomes, the Cerrado (a savannah environment), and the Atlantic Forest. In the present study, we evaluated morphological variation within and among five populations located in these vegetation types and in transitional sites in order to test the hypothesis that habitat selective pressures, being different in the Cerrado and the Atlantic Forest, would cause adaptive differences in morphological traits in individuals occurring under these different circumstances. Thirteen morphological traits of fruits, seeds, and of the membranous endocarp were obtained from 30 fruits and 20 seeds from each of nine to 10 individuals per population. Significant variation was found for all traits while comparing individuals within populations, and most traits varied significantly among populations as well. Some traits differed significantly between forest and Cerrado populations, while transition sites showed intermediate patterns and higher within-population variation. Contrary to our hypothesis, variation in seed size and mass among populations from different habitats was not significant. However, as predicted, the membranous endocarp was shorter for the seeds from Cerrado populations than from the Atlantic Forest. These data suggest the existence of P. reticulata ecotypes from Cerrado and Atlantic Forest; the relevance to Plathymenia evolution and to its wide ecological distribution is discussed.     

Genetic diversity and structure of natural populations of Plathymenia reticulata (Mimosoideae), a tropical tree from the Brazilian Cerrado

Plathymenia reticulata is a tropical tree native to the Brazilian Cerrado, one of the most important and endangered ecosystems in Brazil. This species presents high-quality wood and potential for recovery of degraded areas. Despite its importance, almost nothing is known about its genetic or ecological features. Random amplified polymorphic DNA (RAPD) markers were used to investigate the genetic diversity and structure of six natural populations of P. reticulata. DNAs from 117 adult individuals were amplified with 10 random primers and Shannon's index and amova were used to evaluate the levels of genetic diversity within and among populations. Through 72 markers, 70.8% of which were polymorphic, it was possible to obtain 117 unique RAPD phenotypes. The levels of genetic variability found in the six populations of P. reticulata were considerable and most of the genetic variation was found between individuals within populations, although pairwise PH(ST) values indicated significant divergence between populations. The among-population component accounted for, respectively, 12.3% and 16% of the genetic variation, according to amova and Shannon's index. These results were compared with other genetic studies on plant species and such a level of differentiation among populations corresponds to that which has usually been observed for outcrossing plants. The importance of maintenance of the P. reticulata populations and implications of the analysis of adult individuals, considering the longevity of this species and the relatively recent Cerrado fragmentation, are discussed.     

Molecular differentiation of two vicariant neotropical tree species, Plathymenia foliolosa and P. reticulata (Mimosoideae), inferred using RAPD markers

 Plathymenia foliolosa and P. reticulata are two tropical tree species economically important for their high quality wood. P. foliolosa occurs mainly in areas of Atlantic Forest (a tropical forest) whereas P. reticulata occurs mainly in the Cerrado region (a savanna vegetation), both Brazilian biomes classified as hotspots for conservation priorities. In the present study RAPD markers were used to differentiate P. foliolosa from the vicariant species P. reticulata. Using 10 random primers it was possible to obtain 84 markers, of which 22 (26.2%) were present in just one of the two species. Nine of the ten primers were successful in discriminating between the species through the detection of diagnostic markers or band frequency differences. One of the populations of P. foliolosa, located in a region where the two species co-occur, presented several markers that were characteristic of P. reticulata, suggesting the occurrence of gene flow between the two species. Received September 3, 2001; accepted August 19, 2002 Published online: November 22, 2002 Addresses of the authors: Daniela Rodrigues Lacerda (dlacerda@dedalus.lcc.ufmg.br), Maria Bernadete Lovato (lovatomb@icb.ufmg.br), Maria Dolores Porto Acedo (acedomd@icb.ufmg.br), Dept. Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CP: 486, Belo Horizonte, MG, 31270-901, Brasil. José Pires de Lemos Filho (lemos@icb.ufmg.br), Dept. Botanica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CP: 486, Belo Horizonte, MG, 31270-901, Brasil.     

Latitudinal Variation in Termite Species Richness and Abundance along the Brazilian Atlantic Forest Hotspot

In this study, we investigated the termites of the Brazilian Atlantic Forest, one of the most threatened biodiversity hotspots in the world, in regularly spaced sites from 7° S to 27° S latitude. To our knowledge, this is the only report of a latitudinal survey of termites at species level performed with a standardized sampling protocol. We evaluate termite diversity and abundance, and describe patterns of species composition based on feeding groups along the latitudinal gradient. We also describe the relative contribution of environmental variables to explain diversity patterns. Termite assemblages were investigated by standardized surveys at 15 Atlantic Forest sites, on six transects divided into five sections of 10 m², with 30 sections per site (or 300 m²/site), which were investigated by one trained person for one hour. Observed species richness and abundance were negatively correlated with latitude. The influence of latitude was explained mainly by variables related to temperature, precipitation and ambient energy (potential evapotranspiration). Our results also suggest that temperature exerts a greater constraint on Atlantic Forest termites than productivity, because ambient productivity increases with latitude in this forest but termite diversity decreases. Termite species richness in the Atlantic Forest showed a different pattern than those described for other organisms, increasing in diversity where the coastal‐forest strip narrows. Overall, our results indicate comparatively high termite species richness at northeastern sites and a significant impoverishment of termite assemblages in the southeastern and southern regions of the Atlantic Forest.     

Genetic variation in remnant populations of Dalbergia nigra (Papilionoideae), an endangered tree from the Brazilian Atlantic Forest

BACKGROUND AND AIMS: Dalbergia nigra, known as Brazilian rosewood, is an endangered tree species restricted to the Brazilian Atlantic Forest and has been intensively logged for five centuries due to its high-quality wood. The objective of the present study was to assess the genetic variation and structure in adults and saplings of the species from a large reserve of the Atlantic Forest, the Rio Doce State Park, and from two small surrounding fragments, one better preserved and another with a high degree of anthropogenic disturbance. METHODS: Analyses of genetic variation and structure were conducted by studying allozyme markers. Seven putative enzymatic loci were resolved, five of them being polymorphic. KEY RESULTS: The mean numbers of alleles per locus (A) were 1.93 and 1.73, while the percentages of polymorphic loci (P) were 93 and 73 % for adults and saplings, respectively. Saplings from the fragment with high anthropogenic disturbance exhibited the lowest values of A and P. The fragment that constitutes a conservation area exhibited genetic variation similar to the population from the large reserve. The observed (H(o)) and expected (H(e)) heterozygosities were not significantly different among the three populations. Only sapling populations showed F(ST) values (divergence among populations) significantly different from zero over all studied loci. The fragment with high anthropogenic disturbance exhibited considerable genetic divergence in relation to the above-cited populations. CONCLUSIONS: The evaluated populations displayed mean levels of genetic variation intermediate to those expected for narrow and widespread species. The results suggest that fragments with similar area and geographical distance from a large protected reserve can exhibit different levels of genetic variation, depending on the degree of anthropogenic disturbance. The considerable genetic variation in the protected fragment points to the importance of adequate conservation of small fragments for the preservation of genetic variation in D. nigra.     

Parameter stability of the functional-structural plant model GREENLAB as affected by variation within populations, among seasons and among growth stages

BACKGROUND AND AIMS: It is increasingly accepted that crop models, if they are to simulate genotype-specific behaviour accurately, should simulate the morphogenetic process generating plant architecture. A functional-structural plant model, GREENLAB, was previously presented and validated for maize. The model is based on a recursive mathematical process, with parameters whose values cannot be measured directly and need to be optimized statistically. This study aims at evaluating the stability of GREENLAB parameters in response to three types of phenotype variability: (1) among individuals from a common population; (2) among populations subjected to different environments (seasons); and (3) among different development stages of the same plants. METHODS: Five field experiments were conducted in the course of 4 years on irrigated fields near Beijing, China. Detailed observations were conducted throughout the seasons on the dimensions and fresh biomass of all above-ground plant organs for each metamer. Growth stage-specific target files were assembled from the data for GREENLAB parameter optimization. Optimization was conducted for specific developmental stages or the entire growth cycle, for individual plants (replicates), and for different seasons. Parameter stability was evaluated by comparing their CV with that of phenotype observation for the different sources of variability. A reduced data set was developed for easier model parameterization using one season, and validated for the four other seasons. KEY RESULTS AND CONCLUSIONS: The analysis of parameter stability among plants sharing the same environment and among populations grown in different environments indicated that the model explains some of the inter-seasonal variability of phenotype (parameters varied less than the phenotype itself), but not inter-plant variability (parameter and phenotype variability were similar). Parameter variability among developmental stages was small, indicating that parameter values were largely development-stage independent. The authors suggest that the high level of parameter stability observed in GREENLAB can be used to conduct comparisons among genotypes and, ultimately, genetic analyses.     

Humidity levels drive reproductive modes and phylogenetic diversity of amphibians in the Brazilian Atlantic Forest

Aim The diversity of reproductive modes among amphibians constitutes a striking example of how differences in the biology of species provide important explanations for species distribution patterns on a broad scale. We hypothesize that sites with a higher humidity level will support more modes of reproduction than drier sites and will consequently exhibit a higher phylogenetic diversity. Furthermore, if there is a gradient in the tolerance of reproductive modes to desiccation, there will be a nested pattern in the composition of reproductive modes among sites. Location Twenty‐seven forest sites in the Brazilian Atlantic Forest. Methods Through a path analysis approach, we evaluated the direct and indirect effects of the humidity level on the number of reproductive modes, as well as the relative importance of both variables on amphibian phylogenetic diversity. A nestedness analysis was used to quantify the extent to which the compositions of both species and reproductive modes in drier sites correspond to subsets of those in sites with higher annual precipitation. Results We found that the reproductive modes present in drier sites are non‐random subsets of those present in sites with higher humidity levels. Because reproductive modes are phylogenetically conserved among amphibians, sites with a greater number of reproductive modes supported greater phylogenetic diversity. Sites with high precipitation throughout the year provided suitable environmental conditions for a larger number of reproductive modes, whereas sites with low precipitation and typical seasonal climates supported only those reproductive modes specialized to resist desiccation. Main conclusions Our results show that humidity‐related variables are key environmental factors related to both the richness of reproductive modes and phylogenetic diversity. Our results support the hypothesis that the higher phylogenetic diversity found in moister sites reflects differences in the tolerance to desiccation among different reproductive modes. Given that reproductive modes are associated with susceptibility to desiccation, their incorporation into explanatory models may trigger a significant advance in the understanding of the mechanisms regulating the species richness and composition of amphibian communities.     

Genetic structure and conservation of Mountain Lions in the South-Brazilian Atlantic Rain Forest

The Brazilian Atlantic Rain Forest, one of the most endangered ecosystems worldwide, is also among the most important hotspots as regards biodiversity. Through intensive logging, the initial area has been reduced to around 12% of its original size. In this study we investigated the genetic variability and structure of the mountain lion, Puma concolor. Using 18 microsatellite loci we analyzed evidence of allele dropout, null alleles and stuttering, calculated the number of allele/locus, PIC, observed and expected heterozygosity, linkage disequilibrium, Hardy-Weinberg equilibrium, F(IS), effective population size and genetic structure (MICROCHECKER, CERVUS, GENEPOP, FSTAT, ARLEQUIN, ONESAMP, LDNe, PCAGEN, GENECLASS software), we also determine whether there was evidence of a bottleneck (HYBRIDLAB, BOTTLENECK software) that might influence the future viability of the population in south Brazil. 106 alleles were identified, with the number of alleles/locus ranging from 2 to 11. Mean observed heterozygosity, mean number of alleles and polymorphism information content were 0.609, 5.89, and 0.6255, respectively. This population presented evidence of a recent bottleneck and loss of genetic variation. Persistent regional poaching constitutes an increasing in the extinction risk.     

Fine-scale spatial genetic structure of Dalbergia nigra (Fabaceae), a threatened and endemic tree of the Brazilian Atlantic Forest

The Atlantic Forest is one of the most diverse ecosystems in the world and considered a hotspot of biodiversity conservation. Dalbergia nigra (Fabaceae) is a tree endemic to the Brazilian Atlantic Forest, and has become threatened due to overexploitation of its valuable timber. In the present study, we analyzed the genetic diversity and fine-scale spatial genetic structure of D. nigra in an area of primary forest of a large reserve. All adult individuals (N = 112) were sampled in a 9.3 ha plot, and genotyped for microsatellite loci. Our results indicated high diversity with a mean of 8.6 alleles per locus, and expected heterozygosity equal to 0.74. The co-ancestry coefficients were significant for distances among trees up to 80 m. The Sp value was equal to 0.017 and indirect estimates of gene dispersal distances ranged from 89 to 144 m. No strong evidence of bottleneck or effects of human-disturbance was found. This study highlights that long-term efforts to protect a large area of Atlantic Forest have been effective towards maintaining the genetic diversity of D. nigra. The results of this study are important towards providing a guide for seed collection for ex-situ conservation and reforestation programmes of this threatened species.     

Social and demographic influences on the feeding ecology of giraffe in the Luangwa Valley,Zambia: 1973–2014

Body size influences metabolic rate, which impacts feeding ecology. Body mass differs by sex in size‐dimorphic species, such as giraffes, and also by age. Giraffes reside in a fission–fusion social system, which influences feeding ecology due to frequent changes in group size and composition. We analysed 40 years of feeding records collected from a population of Thornicroft's giraffes (Giraffa camelopardalis thornicrofti) living in the Luangwa Valley, Zambia. We examined the influence of herd composition, age and sex on diet. Solitary males and herd males did not differ in diet. Dietary diversity was comparable for females and males, with sex differences in plant species eaten present during the dry season. Age differences in feeding ecology were pronounced, with juveniles often feeding on bushes and smaller trees, while adults tended to feed upon taller trees. Both sexes have evolved foraging strategies that maximize nutrient and energy intake commensurate with their reproductive strategies, with male metabolic requirements sometimes greater, and sometimes less, than that of females. We propose that females are not exchanging foraging efficiency with reproductive tactics by feeding on smaller trees in the open, but are increasing prospects for their calves to survive when confronted with interspecific competition by browsers.     

Species richness, composition and abundance of fruit-feeding butterflies in the Brazilian Atlantic Forest: comparison between a fragmented and a continuous landscape

Aim  To evaluate frugivorous butterflies as indicators of forest disturbance in the Brazilian Atlantic Forest.
Location  The study area is located in the municipality of Cotia, São Paulo State, south-eastern Brazil (23°35'−23°50' S, 46°45'−47°15' W).
Methods  Sampling was done at four sites inside a large forest block, the Morro Grande State Reserve, and in five forest fragments in an adjacent fragmented landscape. Butterflies were sampled with portable traps, baited with a fermented mixture of banana and sugar cane juice. Sampling was carried out during the period most favourable for the capture of frugivorous butterflies in south-eastern Brazil.
Results  All richness-related results indicated no effect of forest fragmentation on the frugivorous butterfly guild, concurring with the suggestion of appreciable resistance of Atlantic Forest butterflies to habitat modification. However, species composition discriminated between the two landscapes, indicating that fragmentation may have effects beyond simple species richness. When species were analysed individually, clear patterns of distribution emerged, with some species that were very abundant in the fragmented landscape being practically absent in the continuous landscape, and vice versa. This pattern seems consistent even for some subfamilies.
Main conclusion  Our findings support the usefulness of the frugivorous butterfly guild as a biological indicator of forest disturbance effects in one of the world's most threatened ecosystems.     

Abundance and Diversity of Euglossine Bees in the Fragmented Landscape of the Brazilian Atlantic Forest1

Male euglossine bees were sampled with chemical baits every two months from September 1997 to July 1999 at nine sites in the Desengano mountain range, Rio de Janeiro State, Brazil. Four sites were located in Atlantic Forest mature second growth, two sites in disturbed forest, and three sites in forest fragments of 200, 156, and 14 ha, respectively. We collected 3653 male euglossine bees from at least 21 species. Analyses of variance indicated no differences among the three habitat types for total number of bees, and 5 of the 6 dominant species. Bootstrapping indicated significant variation in species richness and diversity for some sites, but there was no clear indication of differences among habitats. Similarity as measured with the Morisita–Horn index was inversely related to distance between sites, but relatively high for most site combinations. These results suggest that the euglossine bee community in the three habitats was essentially the same. Although some species were associated with each habitat type, most appeared to respond to temporal local conditions. Our results do not support the hypothesis that forest fragmentation or habitat alteration reduces abundance and diversity of euglossine bees.     

Functional connectivity and genetic diversity of Eulaema atleticana (Apidae,Euglossina) in the Brazilian Atlantic Forest Corridor: assessment of gene flow

The mobility and dispersal of organisms affect population genetics and dynamics, and consequently affect persistence and the risk of extinction. Thus, it is important to understand how organisms move in the fragmented landscapes in order to manage populations and predict the effects of habitat changes on species persistence. This study evaluated the functional connectivity of an orchid bee (Eulaema atleticana Nemésio, 2009) with a high fidelity to forest habitats in the Brazilian Atlantic Forest Corridor by analyzing genetic diversity, spatial genetic structure, and gene flow estimated from microsatellite and mitochondrial markers. Genetic diversity was not correlated with area of the forest fragments, or with forest isolation. At the mosaic scale, Eulaema atleticana showed no significant or low genetic differentiation, indicating genetic homogeneity among forest fragments. A previous field study indicated that Eulaema atleticana was one of the most sensitive Euglossina bees to forest fragmentation but the present molecular analyses demonstrates that current gene flow is sufficient to maintain genetic variability at the mosaic scale.     

Diversity of plant uses in two Caiçara communities from the Atlantic Forest coast, Brazil

Caiçaras are native inhabitants of the Atlantic coast on southeastern Brazil, whose subsistence is based especially on agriculture and artisanal fishing. Because of their knowledge about the environment acquired through generations, Caiçara people can play an important role in Atlantic Forest conservation. An ethnobotanical study was conducted within two Caiçara communities (Ponta do Almada and Camburí beach, São Paulo State, Brazil), focusing on plant uses. In 102 interviews, 227 plant ethnospecies were quoted, mainly for food, medicine, handicraft and construction of houses and canoes. People from studied communities depend on the native vegetation for more than a half of the species known and used. Using diversity indices, plant uses are compared between studied communities and between gender and age categories within each community. We found quantitative differences in the knowledge about plants between gender categories for each kind of use (medicinal, food and handicrafts). Older and younger informants also have different knowledge about plants for handicraft and medicine, but not for edible plants.     

Male morphological variation and the determinants of body size in two Otiteselline fig wasps

The chalcid wasps (Hymenoptera) that develop in fig tree inflorescences(Ficus: Moraceae) have often been used to study alternativereproductive behaviors. However, recent work suggests that suchbehaviors are more complex than previously thought. We investigatedthis in Otitesella longicauda and O. rotunda. In addition toknown dimorphisms in the two species (each have "religiosa"males that use their mandibles to fight for mates in the fig,and "digitata" males that disperse from the fig to mate), wefound that religiosa males below species-specific body sizeswitch points have relatively larger mandibles and are lesssclerotized than those above. Thus, they are actually trimorphic.We suggest that the religiosa morph variation is linked to fighter/nonfighteralternative mating behaviors, with small (nonfighting) maleshaving relatively larger mandibles because they also use themto pull females out of their galls before mating. Also, we investigatedthe determinants of wasp body size, and whether females (foundresses)adjust their offspring allocation strategies according to expectedoffspring size. We found that wasp size is larger in ovariesnear the center of the fig, and more females and fewer religiosamales are laid in such ovaries than in those further away. Thisprobably indicates that foundresses lay females when they areexpected to be large because their fitness is more body size–dependentthan that of religiosa males. We then discuss the implicationsof our findings for the study of alternative reproductive behaviorsand foundress offspring allocation strategies.     

Medicinal Plants in the Atlantic Forest (Brazil): Knowledge, Use, and Conservation

This study focuses on knowledge of medicinal plants among the Caiçaras (rural inhabitants of the Atlantic Forest coast, Brazil). In particular, we examine the use of medicinal plants according to sex and age to reveal general patterns of Caiçara knowledge and use of plant resources. Data collected through 449 interviews at 12 Caiçara communities (Rio de Janeiro and São Paulo coastal sites) include citations of 249 plants and identification of 227 species. We show the importance of introduced as opposed to native plants and of key individuals for the conservation of the Caiçaras-Atlantic Forest.     

Environment,not phylogeny,drives herbivory and leaf attributes in trees from two contrasting forest formations of the Brazilian Atlantic Forest

ABSTRACT

Background

The degree of herbivory in plants can be related to leaf traits, which are, in turn, determined by phylogeny and environment.     

Molecular phylogeny, biogeography and insights into the origin of parthenogenesis in the Neotropical genus Leposoma (Squamata: Gymnophthalmidae): Ancient links between the Atlantic Forest and Amazonia

Leposoma is a conspicuous component of leaf litter herpetofauna of South and Central American rainforests. The 15 bisexual and one parthenogenetic species are allocated to the parietale and scincoides groups based on morphology. Phylogenetic analyses of 1830 bp (mtDNA + nuclear) were performed on 63 specimens of four species from Amazonian and Panamanian rainforests, and six species and one undescribed form from the Atlantic Forest. Different methods of tree reconstruction were explored, with Anotosaura vanzolinia and Colobosauroides cearensis as outgroups. The monophyly of the parietale and scincoides groups is strongly supported. Contrary to previous hypotheses suggesting a recent contact between Atlantic and Amazon forests, our estimates point to an initial split in Miocene. The position of Leposoma baturitensis, endemic to relictual forests in the semiarid Caatingas northeastern Brazil, and its divergence from the remaining species of the Atlantic Forest, suggests an ancient isolation with no indication of a secondary contact with forests of the eastern coast. Our data do not permit unambiguous assignment of parental species of the unisexual Leposoma percarinatum or the mechanism involved in the origin of parthenogenesis, but revealed two highly divergent diploid and triploid lineages within L. percarinatum, indicating that the unisexuals represent a species complex.     

Correlates of male quality in the field cricket, Gryllus campestris L.: age, size, and symmetry determine pairing success in field populations

Sexual selection in field crickets (Gryllidae) is well documented.Several studies have identified male traits, such as age andbody size, that influence pairing success in the field. HereI show how these traits covary with male quality by examiningthe degree of fluctuating asymmetry in male Gryllus campestris.Older males were both larger and more symmetrical. Principalcomponents analysis suggests that these three variables wereessentially measures of the same trait, male quality. A comparisonof paired and calling males showed that males of high qualitywere more successful in obtaining mates; paired males were older,larger, and more symmetrical. The area of the harp covariedwith morphological traits and determined the carrier frequencyof the male's call. Information related to male quality wastherefore available for female discrimination.     

Mitochondrial DNA variation within and among regional populations of longtail macaques (Macaca fascicularis) in relation to other species of the fascicularis group of macaques

An 835 base pair (bp) fragment of mitochondrial DNA (mtDNA) was sequenced to characterize genetic variation within and among 1,053 samples comprising five regional populations each of longtail macaques (Macaca fascicularis) and rhesus macaques (Macaca mulatta), and one sample each of Japanese (M. fuscata) and Taiwanese (M. cyclopis) macaques. The mtDNA haplotypes of longtail macaques clustered in two large highly structured clades (Fas1 and Fas2) of a neighbor-joining tree that were reciprocally monophyletic with respect to those representing rhesus macaques, Japanese macaques, and Taiwanese macaques. Both clades exhibited haplotypes of Indonesian and Malaysian longtail macaques widely dispersed throughout them; however, longtail macaques from Indochina, Philippines, and Mauritius each clustered in a separate well-defined clade together with one or a few Malaysian and/or Indonesian longtail macaques, suggesting origins on the Sunda shelf. Longtail macaques from Malaysia and Indonesia were far more genetically diverse, and those from Mauritius were far less diverse than any other population studied. Nucleotide diversity between mtDNA sequences of longtail macaques from different geographic regions is, in some cases, greater than that between Indian and Chinese rhesus macaques. Approximately equal amounts of genetic diversity are due to differences among animals in the same regional population, different regional populations, and different species. A greater proportion of genetic variance was explained by interspecies differences when Japanese and Taiwanese macaques were regarded as regional populations of rhesus macaques than when they were treated as separate species. Rhesus macaques from China were more closely related to both Taiwanese and Japanese macaques than to their own conspecifics from India.