As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow tre...As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow trees for wood production as an economic activity.The objective of this study was to quantify the increment of wood density of four forest species from different successional classes of a mixed system of restoration in a neotropical forest in Brazil.Tree discs were sampled at breast height and analyzed radially by X-ray densitometry to obtain apparent density and basic density.Three trees each of a species from the pioneer,early and late secondary successional stages and of the dominant species in the climax community.The radial profiles indicated increasing density from the pith to bark of trunks,except for some variations due to wood defects and growth.Average density was 0.576 g cm^(-3),0.655 g cm^(-3),0.706 g cm^(-3)and 0.775 g cm^(-3),respectively,for Peltophorum dubium,Schinus terebinthifolius,Cariniana estrellensis and Hymenaea courbaril.Radial profiles indicated higher amplitudes in the apparent densities for slow-growing species.X-ray densitometry generated parameters such as minimum,average and maximum densities,and radial density variations.These parameters are important for understanding the ecological functional role of successional classes of the Atlantic Forest from the Neotropical region.展开更多
Parasites are globally widespread pathogenic organisms,which impose im portant selective forces upon their hosts.Thus,in accordance with the A djustm ent to parasite pressure hypothesis,it is expected that defenses am...Parasites are globally widespread pathogenic organisms,which impose im portant selective forces upon their hosts.Thus,in accordance with the A djustm ent to parasite pressure hypothesis,it is expected that defenses among hosts vary relative to the selective pressure imposed by parasites.According to the latitudinal gradient in diversity,species richness and abundance of parasites peak near the equator.The uropygial gland is an im portant defensive exocrine gland against pathogens in birds.Size of the uropygial gland has been proposed to vary among species of birds because of divergent selection by pathogens on their hosts.Therefore,we should expect that bird species from the tropics should have relatively larger uropygial glands for their body size than species from higher latitudes.However,this hypothesis has not yet been explored.Here,we analyze the size of the uropygial gland of 1719 individual birds belonging to 36 bird species from 3 Neotropical(Peru)and 3 temperate areas(Spain).Relative uropygial gland volum e was 12.52%larger in bird species from the tropics than from temperate areas.This finding is consistent w ith the relative size of this defensive organ being driven by selective pressures imposed by parasites.We also explored the potential role of this gland as a means of avoiding haemosporidian infection,showing that species with large uropygial glands for their body size tend to have lower mean prevalence of haemosporidian infection,regardless o f their geographical origin.This result provides additional support for the assum ption that secretions from the uropygial gland reduce the likelihood of becoming infected with haemosporidians.展开更多
Although the importance of mangroves is clearly recognized around the world, these ecosystems are being strongly altered by the logging of their forests for multiple purposes. The Colombian Pacific coast is not an exc...Although the importance of mangroves is clearly recognized around the world, these ecosystems are being strongly altered by the logging of their forests for multiple purposes. The Colombian Pacific coast is not an exception to this situation, and apart from the traditional logging of wood, the hunting of the Neotropical Cormorant or Pato-cuervo (Phalacrocorax brasilianus), an activity largely unknown but widespread in the region, is also causing the logging of great extensions of mangroves. The aim of this research was to determine if the assemblages of mollusks and crustaceans of these mangroves are being affected by the hunting of the cormorant. To answer this question, quantitative samplings were realized in four transects in logged and unlogged mangrove areas on the southwestern coast of the Colombian Pacific and diversity, equitability and dominance of macrofaunal assemblages of mangroves were calculated. The data show that although significant differences between diversity indices were not found, there were important differences in equitability (total J’: 0.55 in T1, 0.77 in T2, 0.46 in T3 and 0.65 in T4), specific dominance, and composition of species (T1: 11 species, T2: 13, T3: 9 and T4: 11) between logged and unlogged areas. Based on these results, although forest structure and interstitial salinity were different among transects, we conclude that the present practice of exploitation of the Neotropical Cormorant is affecting the epifaunal populations of mangroves, causing changes in the composition and dominance of species.展开更多
Fusaea occurs in Colombia, Venezuela, the three Guianas, Ecuador, Peru, Brazi land Bolivia. It is found in non inundated and inundated rain forest at elevations from sea level to 600(-900)m. It is distinct from other...Fusaea occurs in Colombia, Venezuela, the three Guianas, Ecuador, Peru, Brazi land Bolivia. It is found in non inundated and inundated rain forest at elevations from sea level to 600(-900)m. It is distinct from other related genera by its conspicuous ring of staminodes formed by the enlarged outer stamens, which is unique in the Annonaceae, and by an entirely fused calyx, combined with the fully syncarpous fruits with a basal collar. The general wood anatomical characters are in line with the very specific wood anatomy of the family, characterized by the tangential, concentric parenchyma bands. There is, however, one very specific feature in Fusaea : the small rhombic crystals in the ray cells. From the combined evidence from flower, fruit and pollen morphology, we can conclude that Fusaea is closely related to Duckeanthus, Duguetia, Pachypodanthium, Letestudoxa and probably Pseudartabotrys . Based on measurements of the diagnostic features on all the 158 available specimens identified either as F.longifolia or F.decurrens , we constructed three scatter diagrams to show the continuous variation of the distinguishing characters previously used. F.decurrens is obviously within the morphological variation range of F.longifolia , and is therefore brought into synonymy with the latter. Two species, i.e., F.longifolia and F.peruviana , are recognized in this genus.展开更多
Phillipsia olivacea is an uncommon discomycete record from Brazil.It was described originally from South Brazil and later recorded from Central America and northern South America.Now it is found for the first time fro...Phillipsia olivacea is an uncommon discomycete record from Brazil.It was described originally from South Brazil and later recorded from Central America and northern South America.Now it is found for the first time from a montane forest in the Brazilian semiarid region.Description,discussion,photography of the ascomata and drawings are provided.展开更多
Elucidating the historical processes that led populations to their current spatial and genetic arrangement is relevant in conserving threatened species. We interpreted the phylogeographic structure of the threatened Y...Elucidating the historical processes that led populations to their current spatial and genetic arrangement is relevant in conserving threatened species. We interpreted the phylogeographic structure of the threatened Yellow-headed Parrot (Amazona oratrix) with mitochondrial markers and analyzed 98 samples from Mexico, Guatemala, and Belize. We performed analyses of genetic structure, genealogical relationships, demographic history, and divergence times and illustrated the phenotypic variation qualitatively of the sampled individuals. The studies revealed that 92% of the genetic variation is explained between the Mexican Tres Marías Islands, the Mexican Pacific Coast, and the Atlantic groups. These three groups were segregated into two main lineages (Pacific and Atlantic), separated by 26 mutations, leaving A. auropalliata within the Atlantic. We found that both lineages diverged 0.55 million years ago, from which the Atlantic lineage experienced population expansion, high levels of genetic diversity, and a low genetic structure with two phenotypes. The Pacific experienced demographic stability, low levels of diversity, and a genetic structure marked with two phenotypes. Our estimates indicate that this separation occurred in the Pleistocene when the Atlantic clade diverged from Panama and dispersed overland to the Gulf of Mexico. Simultaneously, the Pacific clade departed from the same area to Tres Marías Islands and the Mexican Pacific coast. We deduce that this long-distance event was probably produced by assisted dispersal, but other scenarios appear more parsimonious. We conclude that there is no gene flow between both lineages and that the phylogeographic structure resulted significantly from historical events and climatic changes during the Pleistocene. We propose undertaking other analyses in the future to compare our results and the paraphyletic relationships in A. oratrix.展开更多
In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands： the spermato- phylax, which is attached to the ampull...In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands： the spermato- phylax, which is attached to the ampulla. During mating, males of the neotropical katydid Conocephalus ictus transfer a spermatophylax that is ingested by the females. Fecundity, egg-laying rate and longevity were higher in females that consumed the spermatophylax than in those that did not. Also, female receptivity turned off after mating. Females actively rejected other males by hitting them with their forelegs and moving away. Their refractory period lasted as long as 17 d. Only a few females accepted a 2nd mating and died a few days later. In C. ictus, spermatophylax consumption can be beneficial for both males and females. On one hand, the compounds in the spermatophylax or the ejaculate could prevent or delay females from copulating with rivals, thus avoiding sperm competition. On the other hand, such compounds can improve the females＇ opportunity to increase their lifespan and fecundity. Moreover, a rise in egg-laying rate may lower the risk of female prereproductive death caused by rapid oviposition. In any case, the boost in female egg laying might also be beneficial for males because their number of offspring increases.展开更多
Nestling growth of birds can be affected by weather fluctuations.In general,it is expected that higher temper-atures favor growth by improving food availability and nestling metabolism,while rain hinders it by reducin...Nestling growth of birds can be affected by weather fluctuations.In general,it is expected that higher temper-atures favor growth by improving food availability and nestling metabolism,while rain hinders it by reducing foraging efficiency.However,most of these patterns have been described in insectivorous cavity-nesting birds in temperate forests.We tested these predictions in two neotropical grassland ground-nesting birds with contrasting nestling diets and therefore potentially different responses to weather.We measured nestlings of the Hellmayr’s Pipit(Anthus hellmayri,an insectivorous passerine)and the Grassland Yellow-Finch(Sicalis luteola,which feeds its nestlings exclusively with seeds)during three breeding seasons(2017-2020)in central-eastern Argentina.We took measurements of tarsus and body mass,modeled growth curves using nonlinear mixed-effects models,and evaluated the effects of minimum daily temperature and precipitation during the growth period and the 30 days prior to hatching.For pipits(60 nestlings from 21 nests),minimum temperatures during the growth period were positively associated with tarsus and body mass asymptotes.Also,there was a positive association between precipitation during the pre-hatching period and tarsus asymptote.Conversely,none of the weather variables analyzed had significant effects on nestling growth of finches(131 nestlings from 35 nests).Dietary contrast between species may explain the different results.Arthropod activity and abundance can be affected by weather variations within the span of a breeding season,whereas seeds may depend on conditions from previous years,making the effects harder to detect.Fledglings with reduced asymptotic size can have reduced chances of sur-vival.Hence,pipit populations could be impacted if they experience cold and dry conditions during their breeding season,which is of major relevance in the current context of climate change.展开更多
The decrease in species richness toward higher latitudes is an expected biogeographical pattern.This pattern could be related to particular envi-ronmental constraints and the evolutionary history of clades.However,spe...The decrease in species richness toward higher latitudes is an expected biogeographical pattern.This pattern could be related to particular envi-ronmental constraints and the evolutionary history of clades.However,species richness does not fully represent the evolutionary history of the clades behind their distributions.Phylogenetic diversity better clarifies the role of historical factors in biogeographical patterns.We analyzed envi-ronmental and historical drivers related to latitudinal variation in species richness and phylogenetic diversity of Atlantic Forest endemic snakes.We implemented species distribution models,from voucherbased locality points,to map the snake ranges and diversity.We used generalized additive mixed models to evaluate the relationships among the diversity metrics and area,topographical roughness,and past climate change velocity since the Last Maximum Glacial in the Atlantic Forest latitudinal gradient.Contrary to the expected general pattern,species richness was higher toward higher latitudes,being positively related to past climatic stability.Species richness also increased with total area and higher topographical roughness.Phylogenetic diversity,on the other hand,showed opposite relationships related to the same factors.Phylogenetic diversity increased with lower climatic stability in lower latitudes.Thus,dimensions of diversity were affected in different ways by historical and environmental constraints in this unique and threatened biodiversity hotspot.展开更多
Aggressive behavior can be an important factor in determining how animals use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including ...Aggressive behavior can be an important factor in determining how animals use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including water temperature and resource levels. In this study, we tested if the amount of habitat structure in the environment affected aggression levels in female convict cichlids Archocentrus nigrofasciatus. We performed a laboratory experiment in which we placed female convict cichlids into an aquarium with low or high amounts of habitat structure and monitored the dominant female＇s behavior toward the subordinate female. Aggressive behavior in convict cichlids primarily consists of chases and bites. We found that the total time the dominant female spent chasing the subordinate female was greater when there was a low amount of habitat structure as compared to when there was a high amount of habitat structure. We also found that both the average duration of a chasing bout and the number of bites directed at the subordinate fish increased when there was a low amount of structure, but the number of chases did not. These results indicate that increased habitat structural complexity decreases aggressive behavior in convict cichlids [Current Zoology 56 （1）： 52-56, 2010].展开更多
I review evidence that females deceive males in the context of sexual selection and sexual conflict in the green poison frog, Dendrobates auratus. In this species, males mate polygynously when they have the opportunit...I review evidence that females deceive males in the context of sexual selection and sexual conflict in the green poison frog, Dendrobates auratus. In this species, males mate polygynously when they have the opportunity, but polygyny imposes a cost on female reproductive success. Some females attempt to guard their mates when those males are approached by other fe- males. This behavior involves both aggression toward other females and active ＂pseudo-courtship＂ of the male. This courtship is hypothesized to be a deceptive signal that ffmctions to prevent the male from mating with other females. Observational and com- parative evidence is presented in support of the predictions of this hypothesis. This form of deception is compared to similar be- haviors that occur in other species, and the possibility that other forms of deception occur in poison frogs is discussed展开更多
The water relations balance parameters of plant tissue have been determined under field condition.They are the osmotic potentials at saturation (nsat), the osmotic potentials at the turgid loss point (ntlp), modulusof...The water relations balance parameters of plant tissue have been determined under field condition.They are the osmotic potentials at saturation (nsat), the osmotic potentials at the turgid loss point (ntlp), modulusof elasticity and the water saturation deficiency at turgid loss point (Wsdtlp) of 30 adult woody species fromCerrado vegetetion (neotropical savanna) in the wet and dry seasons of Brazil. And the changing patterns of Sevalues of each species have been compared and analyzed in different methods. The mean values of nsat, ntlp, and Wsdtlp of 30 species in the wet season were -2.11 MPa, -2.50 MPa, 19.66 MPa and 10.27 % respectively.Responding to water stress in the dry season, the values of nsat of 24 species, the ntlp and the of 17 speciesthe Wsdtpl of 6 species significantly went down or up comparing with those in the wet season (P < 0.05)- Only 3species had not changed their water parameters significantly any more. The mean values of nsat, ntlp, andWsdtlp of 30 species were adjusted to be -2.28 MPa, -2.84 MPa, 18.58 MPa and 8.19 % respectively. The species that have lower values on the mt have higher vaIues on e. Contrary, the specles that have higher valueson the nsat have lower values on . The special strategies of 30 Cerrado species have been divided. into 3 typesin Cluster Analysis Method. Every type has the distinct water balance mechanism and the parameter-adjustingpattern.展开更多
The interaction between organisms and their environment is central in functional morphology.Differences in habitat usage may imply divergent morphology of locomotor systems;thus,detecting which morphological traits ar...The interaction between organisms and their environment is central in functional morphology.Differences in habitat usage may imply divergent morphology of locomotor systems;thus,detecting which morphological traits are conservative across lineages and which ones vary under environmental pressure is important in evolutionary studies.We studied internal and external morphology in 28 species of Neotropical anurans.Our aim was to determine if internal morphology(muscle and tendons)shows lower phylogenetic signal than external morphology.In addition,we wanted to know if morphology varies in relation to the habitat use and if there are different functional groups.We found differences in the degree of phylogenetic signal on the groups of traits.Interestingly,postaxial regions of the forelimb are evolutionarily more labile than the preaxial regions.Phylomorphospace plots show that arboreal(jumpers and graspers)and swimmer frogs cluster based on length of fingers and the lack of sesamoid,also reflected by the use of habitat.These functional clusters are also related to phylogeny.Sesamoid and flexor plate dimensions together with digit tendons showed to be important to discriminate functional groups as well as use of habitat classification.Our results allow us to identify a"grasping syndrome"in the hand of these frogs,where palmar sesamoid and flexor plate are absent and a third metacarpal with a bony knob are typical.Thus,a lighter skeleton,long fingers and a prensile hand may be key for arboreality.展开更多
The breeding traits of Sporophila seedeaters have been relatively well studied in recent years;nevertheless,a group of ten species in the genus,known as southern capuchinos,remain understudied.That is the case with Ch...The breeding traits of Sporophila seedeaters have been relatively well studied in recent years;nevertheless,a group of ten species in the genus,known as southern capuchinos,remain understudied.That is the case with Chestnut Seedeater(Sporophila cinnamomea),a species vulnerable to extinction,which breeds in the grasslands of southeast South America and,after reproduction,migrates towards the Cerrado region in central Brazil.Here,we investigated breeding ecology and calculated average clutch size,productivity,the sex ratio of nestlings,and estimated nest success.Then we tested(1)whether there is a relationship between the number of active nests and environmental variables,(2)whether the nestling sex ratio deviates from the 1:1 ratio,(3)whether clutch size varies between breeding seasons,and(4)whether the nest success is related to starting date,nest age,plant support,nest height from the ground,and clutch size.During two breeding seasons(October-March 2018-2020),we monitored 98 nests.We generated survival models with five interacting covariates to assess the survival of the nests.We recorded the entire breeding period for Chestnut Seedeater,which was estimated to be 4.6 months,similar to other migratory seedeaters.Clutch size did not differ between breeding seasons.The sex ratio of nestlings was not significantly different from the 1:1 ratio.Nest success was 31%,and predation was the leading cause of unsuccessful nests(83%).The daily survival rate was 0.95±0.01.The main predictor of nest survival was the covariate starting date.These findings,added to other aspects of the species’natural history described here,may help illuminate the ecology and behavior of Chestnut Seedeater and other southern endangered capuchinos,and grassland-dependent species of South America.展开更多
Proper phylogenetic reconstruction is crucial for understanding many evolutionary phenomena. In spite of the great success of molecular phylogenetics, DNA signal still may be limited by some intrinsic constraints such...Proper phylogenetic reconstruction is crucial for understanding many evolutionary phenomena. In spite of the great success of molecular phylogenetics, DNA signal still may be limited by some intrinsic constraints such as codon usage bias. The phylogenetic relationships between the five species subgroups of the Drosophila saltans group are a good example of conflicting molecular phylogenies drawn from different genes due to an ancestral substitutional shift. Here, forty morphological characters were analyzed using the same set of species used in previous molecular studies, with at least a single representative of each subgroup. The cladistic analysis was in disagreement with most of the previous hypotheses in placing the sturtevanti subgroup as an early branch, whereas the four remaining subgroups form a well supported clade that can be further subdivided into two sister clades： one containing the cordata and the elliptica subgroups, whereas the second includes the parasaltans and the saltans subgroups. The molecular evolution （codon usage bias） of the saltans group were revised in light of the present finding. The analysis highlights the important role of morphology in phylogeny reconstruction and in understanding molecular evolutionary phenomena.展开更多
We provide a list of bird species for Ribeira lagoon, a protected area in Rio de Janeiro, southeastern Brazil. Data were obtained in monthly surveys in points along a continuous transect, between August 2008 and July ...We provide a list of bird species for Ribeira lagoon, a protected area in Rio de Janeiro, southeastern Brazil. Data were obtained in monthly surveys in points along a continuous transect, between August 2008 and July 2009, and 21 ad libitum observations. In total, 174 species were listed, including 121 land birds and 53 waterbirds. Of these, 11 are considered threatened at regional level. Waterbird richness was significantly higher in the dry season (April to September) than in the rainy season (October to March), whereas land bird richness remained constant. However, land bird richness varied throughout the year, with the highest value in February 2009 (77 species) and the lowest in May 2009 (41 species). The species listed account for 23% of the total of 745 bird species listed for Rio de Janeiro, and for 49% of 108 waterbirds recorded for the state.展开更多
A bryophyte propagule bank serves as a source for population maintenance and survival, and many factors can influence these propagules’ germination. However, it is unknown how soil depths affect propagules banks, the...A bryophyte propagule bank serves as a source for population maintenance and survival, and many factors can influence these propagules’ germination. However, it is unknown how soil depths affect propagules banks, their diversity and abundance overtime in a Neotropical forest. To understand such a paradigm, soil samples were obtained from different depths (0 - 5 cm, 5 - 10 cm, and 10 - 15 cm) at Guajataca State Forest, Puerto Rico;then, they were transferred to the laboratory, cultured, and the amount of gametophytes from propagules present over a seven-month period were measured. Forest soil depth did affect the density of gametophytes. Gametophytes densities augmented overtime for almost all species. Two species mainly influenced the propagule production over time. Also, propagules can have a long-term germination potential for some species.展开更多
基金This study is funded by the Coordination for the Improvement of Higher Education Personnel(CAPES).
文摘As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow trees for wood production as an economic activity.The objective of this study was to quantify the increment of wood density of four forest species from different successional classes of a mixed system of restoration in a neotropical forest in Brazil.Tree discs were sampled at breast height and analyzed radially by X-ray densitometry to obtain apparent density and basic density.Three trees each of a species from the pioneer,early and late secondary successional stages and of the dominant species in the climax community.The radial profiles indicated increasing density from the pith to bark of trunks,except for some variations due to wood defects and growth.Average density was 0.576 g cm^(-3),0.655 g cm^(-3),0.706 g cm^(-3)and 0.775 g cm^(-3),respectively,for Peltophorum dubium,Schinus terebinthifolius,Cariniana estrellensis and Hymenaea courbaril.Radial profiles indicated higher amplitudes in the apparent densities for slow-growing species.X-ray densitometry generated parameters such as minimum,average and maximum densities,and radial density variations.These parameters are important for understanding the ecological functional role of successional classes of the Atlantic Forest from the Neotropical region.
基金This work was supported by the Spanish Ministry of Economy and Competitiveness research projects[grant CGL2015-64650P]Junta de Extremadura[grant IB16121]S.M.and A.M.were supported by a Ph.D.grant from the Ministry of Economy and Competition of Spain and a mobility grant of Junta de Extremadura(129/2015),respectively.L.G.-L.was supported by the Junta de Extremadura[PO17024,Post-Doc grant].
文摘Parasites are globally widespread pathogenic organisms,which impose im portant selective forces upon their hosts.Thus,in accordance with the A djustm ent to parasite pressure hypothesis,it is expected that defenses among hosts vary relative to the selective pressure imposed by parasites.According to the latitudinal gradient in diversity,species richness and abundance of parasites peak near the equator.The uropygial gland is an im portant defensive exocrine gland against pathogens in birds.Size of the uropygial gland has been proposed to vary among species of birds because of divergent selection by pathogens on their hosts.Therefore,we should expect that bird species from the tropics should have relatively larger uropygial glands for their body size than species from higher latitudes.However,this hypothesis has not yet been explored.Here,we analyze the size of the uropygial gland of 1719 individual birds belonging to 36 bird species from 3 Neotropical(Peru)and 3 temperate areas(Spain).Relative uropygial gland volum e was 12.52%larger in bird species from the tropics than from temperate areas.This finding is consistent w ith the relative size of this defensive organ being driven by selective pressures imposed by parasites.We also explored the potential role of this gland as a means of avoiding haemosporidian infection,showing that species with large uropygial glands for their body size tend to have lower mean prevalence of haemosporidian infection,regardless o f their geographical origin.This result provides additional support for the assum ption that secretions from the uropygial gland reduce the likelihood of becoming infected with haemosporidians.
文摘Although the importance of mangroves is clearly recognized around the world, these ecosystems are being strongly altered by the logging of their forests for multiple purposes. The Colombian Pacific coast is not an exception to this situation, and apart from the traditional logging of wood, the hunting of the Neotropical Cormorant or Pato-cuervo (Phalacrocorax brasilianus), an activity largely unknown but widespread in the region, is also causing the logging of great extensions of mangroves. The aim of this research was to determine if the assemblages of mollusks and crustaceans of these mangroves are being affected by the hunting of the cormorant. To answer this question, quantitative samplings were realized in four transects in logged and unlogged mangrove areas on the southwestern coast of the Colombian Pacific and diversity, equitability and dominance of macrofaunal assemblages of mangroves were calculated. The data show that although significant differences between diversity indices were not found, there were important differences in equitability (total J’: 0.55 in T1, 0.77 in T2, 0.46 in T3 and 0.65 in T4), specific dominance, and composition of species (T1: 11 species, T2: 13, T3: 9 and T4: 11) between logged and unlogged areas. Based on these results, although forest structure and interstitial salinity were different among transects, we conclude that the present practice of exploitation of the Neotropical Cormorant is affecting the epifaunal populations of mangroves, causing changes in the composition and dominance of species.
文摘Fusaea occurs in Colombia, Venezuela, the three Guianas, Ecuador, Peru, Brazi land Bolivia. It is found in non inundated and inundated rain forest at elevations from sea level to 600(-900)m. It is distinct from other related genera by its conspicuous ring of staminodes formed by the enlarged outer stamens, which is unique in the Annonaceae, and by an entirely fused calyx, combined with the fully syncarpous fruits with a basal collar. The general wood anatomical characters are in line with the very specific wood anatomy of the family, characterized by the tangential, concentric parenchyma bands. There is, however, one very specific feature in Fusaea : the small rhombic crystals in the ray cells. From the combined evidence from flower, fruit and pollen morphology, we can conclude that Fusaea is closely related to Duckeanthus, Duguetia, Pachypodanthium, Letestudoxa and probably Pseudartabotrys . Based on measurements of the diagnostic features on all the 158 available specimens identified either as F.longifolia or F.decurrens , we constructed three scatter diagrams to show the continuous variation of the distinguishing characters previously used. F.decurrens is obviously within the morphological variation range of F.longifolia , and is therefore brought into synonymy with the latter. Two species, i.e., F.longifolia and F.peruviana , are recognized in this genus.
基金supported by the‘Conselho Nacional de Desenvolvimento Científico e Tecnológico’(CNPq)with the Projects‘Programa de Pesquisa em Biodiversidade’(PPBio Proc.60/2009)‘Fungos agaricoides emáreas de Mata Atlântica e Caatinga no Estado da Paraíba’(Edital Universal Proc..420.448/2016-0)+2 种基金‘Produtividade em Pesquisa’(Proc.307922/2014-6)grant for FW‘Iniciação Científica’-IC(Proc.307947/2017-3)scholarship to JCVA.PIBIC-UFPB(IC)with the Project PVA785-2018-‘Revisão e ampliação do acervo de fungos do herbário JPB’(Edital 01/2018/PROPESQ Seleção de Projetos de Iniciação Científica 2018/2019)is also acknowledged for providing scholarship to ABLL.
文摘Phillipsia olivacea is an uncommon discomycete record from Brazil.It was described originally from South Brazil and later recorded from Central America and northern South America.Now it is found for the first time from a montane forest in the Brazilian semiarid region.Description,discussion,photography of the ascomata and drawings are provided.
基金funded by the Program of Support for Research and Technological Innovation Projects (PAPIIT) of the Dirección General de Asuntos del Personal Académico, Universidad Nacional Autónoma de México with project number PAPIIT_IT200722funded by the Consejo Nacional de Humanidades, Ciencia y Tecnologíathe Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México
文摘Elucidating the historical processes that led populations to their current spatial and genetic arrangement is relevant in conserving threatened species. We interpreted the phylogeographic structure of the threatened Yellow-headed Parrot (Amazona oratrix) with mitochondrial markers and analyzed 98 samples from Mexico, Guatemala, and Belize. We performed analyses of genetic structure, genealogical relationships, demographic history, and divergence times and illustrated the phenotypic variation qualitatively of the sampled individuals. The studies revealed that 92% of the genetic variation is explained between the Mexican Tres Marías Islands, the Mexican Pacific Coast, and the Atlantic groups. These three groups were segregated into two main lineages (Pacific and Atlantic), separated by 26 mutations, leaving A. auropalliata within the Atlantic. We found that both lineages diverged 0.55 million years ago, from which the Atlantic lineage experienced population expansion, high levels of genetic diversity, and a low genetic structure with two phenotypes. The Pacific experienced demographic stability, low levels of diversity, and a genetic structure marked with two phenotypes. Our estimates indicate that this separation occurred in the Pleistocene when the Atlantic clade diverged from Panama and dispersed overland to the Gulf of Mexico. Simultaneously, the Pacific clade departed from the same area to Tres Marías Islands and the Mexican Pacific coast. We deduce that this long-distance event was probably produced by assisted dispersal, but other scenarios appear more parsimonious. We conclude that there is no gene flow between both lineages and that the phylogeographic structure resulted significantly from historical events and climatic changes during the Pleistocene. We propose undertaking other analyses in the future to compare our results and the paraphyletic relationships in A. oratrix.
文摘In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands： the spermato- phylax, which is attached to the ampulla. During mating, males of the neotropical katydid Conocephalus ictus transfer a spermatophylax that is ingested by the females. Fecundity, egg-laying rate and longevity were higher in females that consumed the spermatophylax than in those that did not. Also, female receptivity turned off after mating. Females actively rejected other males by hitting them with their forelegs and moving away. Their refractory period lasted as long as 17 d. Only a few females accepted a 2nd mating and died a few days later. In C. ictus, spermatophylax consumption can be beneficial for both males and females. On one hand, the compounds in the spermatophylax or the ejaculate could prevent or delay females from copulating with rivals, thus avoiding sperm competition. On the other hand, such compounds can improve the females＇ opportunity to increase their lifespan and fecundity. Moreover, a rise in egg-laying rate may lower the risk of female prereproductive death caused by rapid oviposition. In any case, the boost in female egg laying might also be beneficial for males because their number of offspring increases.
基金supported by Agencia Nacional de Promocion Científica y Tecnologica,Grant[PICT-2014-3347].
文摘Nestling growth of birds can be affected by weather fluctuations.In general,it is expected that higher temper-atures favor growth by improving food availability and nestling metabolism,while rain hinders it by reducing foraging efficiency.However,most of these patterns have been described in insectivorous cavity-nesting birds in temperate forests.We tested these predictions in two neotropical grassland ground-nesting birds with contrasting nestling diets and therefore potentially different responses to weather.We measured nestlings of the Hellmayr’s Pipit(Anthus hellmayri,an insectivorous passerine)and the Grassland Yellow-Finch(Sicalis luteola,which feeds its nestlings exclusively with seeds)during three breeding seasons(2017-2020)in central-eastern Argentina.We took measurements of tarsus and body mass,modeled growth curves using nonlinear mixed-effects models,and evaluated the effects of minimum daily temperature and precipitation during the growth period and the 30 days prior to hatching.For pipits(60 nestlings from 21 nests),minimum temperatures during the growth period were positively associated with tarsus and body mass asymptotes.Also,there was a positive association between precipitation during the pre-hatching period and tarsus asymptote.Conversely,none of the weather variables analyzed had significant effects on nestling growth of finches(131 nestlings from 35 nests).Dietary contrast between species may explain the different results.Arthropod activity and abundance can be affected by weather variations within the span of a breeding season,whereas seeds may depend on conditions from previous years,making the effects harder to detect.Fledglings with reduced asymptotic size can have reduced chances of sur-vival.Hence,pipit populations could be impacted if they experience cold and dry conditions during their breeding season,which is of major relevance in the current context of climate change.
基金supported by grants from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo(FAPESP 2014/23677-9 and 2020/12658-4)Conselho Nacional de Desenvolvimento Cientifico e Tecnol6gico(CNPq,405447/2016-7).R.J.S.thanks CNPq for the research fellowship(307956/2022-9).J.A.R.A.thanks Instituto Serrapilheira for the postdoctoral fellowship.
文摘The decrease in species richness toward higher latitudes is an expected biogeographical pattern.This pattern could be related to particular envi-ronmental constraints and the evolutionary history of clades.However,species richness does not fully represent the evolutionary history of the clades behind their distributions.Phylogenetic diversity better clarifies the role of historical factors in biogeographical patterns.We analyzed envi-ronmental and historical drivers related to latitudinal variation in species richness and phylogenetic diversity of Atlantic Forest endemic snakes.We implemented species distribution models,from voucherbased locality points,to map the snake ranges and diversity.We used generalized additive mixed models to evaluate the relationships among the diversity metrics and area,topographical roughness,and past climate change velocity since the Last Maximum Glacial in the Atlantic Forest latitudinal gradient.Contrary to the expected general pattern,species richness was higher toward higher latitudes,being positively related to past climatic stability.Species richness also increased with total area and higher topographical roughness.Phylogenetic diversity,on the other hand,showed opposite relationships related to the same factors.Phylogenetic diversity increased with lower climatic stability in lower latitudes.Thus,dimensions of diversity were affected in different ways by historical and environmental constraints in this unique and threatened biodiversity hotspot.
基金Acknowledgements We thank Samantha Hilber for valuable comments on the manuscriPt. RMC thanks G.W. Barlow for countless discussions about behavior and for his unbounded enthusiasm for fishes.
文摘Aggressive behavior can be an important factor in determining how animals use and divide space and resources. Previous studies have shown that aggression in fishes can be influenced by a variety of factors, including water temperature and resource levels. In this study, we tested if the amount of habitat structure in the environment affected aggression levels in female convict cichlids Archocentrus nigrofasciatus. We performed a laboratory experiment in which we placed female convict cichlids into an aquarium with low or high amounts of habitat structure and monitored the dominant female＇s behavior toward the subordinate female. Aggressive behavior in convict cichlids primarily consists of chases and bites. We found that the total time the dominant female spent chasing the subordinate female was greater when there was a low amount of habitat structure as compared to when there was a high amount of habitat structure. We also found that both the average duration of a chasing bout and the number of bites directed at the subordinate fish increased when there was a low amount of structure, but the number of chases did not. These results indicate that increased habitat structural complexity decreases aggressive behavior in convict cichlids [Current Zoology 56 （1）： 52-56, 2010].
文摘I review evidence that females deceive males in the context of sexual selection and sexual conflict in the green poison frog, Dendrobates auratus. In this species, males mate polygynously when they have the opportunity, but polygyny imposes a cost on female reproductive success. Some females attempt to guard their mates when those males are approached by other fe- males. This behavior involves both aggression toward other females and active ＂pseudo-courtship＂ of the male. This courtship is hypothesized to be a deceptive signal that ffmctions to prevent the male from mating with other females. Observational and com- parative evidence is presented in support of the predictions of this hypothesis. This form of deception is compared to similar be- haviors that occur in other species, and the possibility that other forms of deception occur in poison frogs is discussed
文摘The water relations balance parameters of plant tissue have been determined under field condition.They are the osmotic potentials at saturation (nsat), the osmotic potentials at the turgid loss point (ntlp), modulusof elasticity and the water saturation deficiency at turgid loss point (Wsdtlp) of 30 adult woody species fromCerrado vegetetion (neotropical savanna) in the wet and dry seasons of Brazil. And the changing patterns of Sevalues of each species have been compared and analyzed in different methods. The mean values of nsat, ntlp, and Wsdtlp of 30 species in the wet season were -2.11 MPa, -2.50 MPa, 19.66 MPa and 10.27 % respectively.Responding to water stress in the dry season, the values of nsat of 24 species, the ntlp and the of 17 speciesthe Wsdtpl of 6 species significantly went down or up comparing with those in the wet season (P < 0.05)- Only 3species had not changed their water parameters significantly any more. The mean values of nsat, ntlp, andWsdtlp of 30 species were adjusted to be -2.28 MPa, -2.84 MPa, 18.58 MPa and 8.19 % respectively. The species that have lower values on the mt have higher vaIues on e. Contrary, the specles that have higher valueson the nsat have lower values on . The special strategies of 30 Cerrado species have been divided. into 3 typesin Cluster Analysis Method. Every type has the distinct water balance mechanism and the parameter-adjustingpattern.
文摘The interaction between organisms and their environment is central in functional morphology.Differences in habitat usage may imply divergent morphology of locomotor systems;thus,detecting which morphological traits are conservative across lineages and which ones vary under environmental pressure is important in evolutionary studies.We studied internal and external morphology in 28 species of Neotropical anurans.Our aim was to determine if internal morphology(muscle and tendons)shows lower phylogenetic signal than external morphology.In addition,we wanted to know if morphology varies in relation to the habitat use and if there are different functional groups.We found differences in the degree of phylogenetic signal on the groups of traits.Interestingly,postaxial regions of the forelimb are evolutionarily more labile than the preaxial regions.Phylomorphospace plots show that arboreal(jumpers and graspers)and swimmer frogs cluster based on length of fingers and the lack of sesamoid,also reflected by the use of habitat.These functional clusters are also related to phylogeny.Sesamoid and flexor plate dimensions together with digit tendons showed to be important to discriminate functional groups as well as use of habitat classification.Our results allow us to identify a"grasping syndrome"in the hand of these frogs,where palmar sesamoid and flexor plate are absent and a third metacarpal with a bony knob are typical.Thus,a lighter skeleton,long fingers and a prensile hand may be key for arboreality.
基金part of the project"Neotropical Grasslands Connection:Ecology,Migration,and Conservation of the Threatened Chestnut Seedeater Sporophila cinnamomea",supported by the Rufford Foundation,United Kingdom(ID 270441)supported by grants to JRRR and CJC,who received doctoral and postdoctoral fellowships,respectively,from the Coordenacão de Aperfeicoamento de Pessoal de Nível Superior-CAPES(88882.439380/2019-01 and 88882.316294/2019-01)a research grant from the Conselho Nacional de Desenvolvimento Científico e Tecnológico-CNPq(310608/2019-8)。
文摘The breeding traits of Sporophila seedeaters have been relatively well studied in recent years;nevertheless,a group of ten species in the genus,known as southern capuchinos,remain understudied.That is the case with Chestnut Seedeater(Sporophila cinnamomea),a species vulnerable to extinction,which breeds in the grasslands of southeast South America and,after reproduction,migrates towards the Cerrado region in central Brazil.Here,we investigated breeding ecology and calculated average clutch size,productivity,the sex ratio of nestlings,and estimated nest success.Then we tested(1)whether there is a relationship between the number of active nests and environmental variables,(2)whether the nestling sex ratio deviates from the 1:1 ratio,(3)whether clutch size varies between breeding seasons,and(4)whether the nest success is related to starting date,nest age,plant support,nest height from the ground,and clutch size.During two breeding seasons(October-March 2018-2020),we monitored 98 nests.We generated survival models with five interacting covariates to assess the survival of the nests.We recorded the entire breeding period for Chestnut Seedeater,which was estimated to be 4.6 months,similar to other migratory seedeaters.Clutch size did not differ between breeding seasons.The sex ratio of nestlings was not significantly different from the 1:1 ratio.Nest success was 31%,and predation was the leading cause of unsuccessful nests(83%).The daily survival rate was 0.95±0.01.The main predictor of nest survival was the covariate starting date.These findings,added to other aspects of the species’natural history described here,may help illuminate the ecology and behavior of Chestnut Seedeater and other southern endangered capuchinos,and grassland-dependent species of South America.
基金funded by the Prix Jeune Chercheur of the Fondation Bettencourt-Schueller
文摘Proper phylogenetic reconstruction is crucial for understanding many evolutionary phenomena. In spite of the great success of molecular phylogenetics, DNA signal still may be limited by some intrinsic constraints such as codon usage bias. The phylogenetic relationships between the five species subgroups of the Drosophila saltans group are a good example of conflicting molecular phylogenies drawn from different genes due to an ancestral substitutional shift. Here, forty morphological characters were analyzed using the same set of species used in previous molecular studies, with at least a single representative of each subgroup. The cladistic analysis was in disagreement with most of the previous hypotheses in placing the sturtevanti subgroup as an early branch, whereas the four remaining subgroups form a well supported clade that can be further subdivided into two sister clades： one containing the cordata and the elliptica subgroups, whereas the second includes the parasaltans and the saltans subgroups. The molecular evolution （codon usage bias） of the saltans group were revised in light of the present finding. The analysis highlights the important role of morphology in phylogeny reconstruction and in understanding molecular evolutionary phenomena.
文摘We provide a list of bird species for Ribeira lagoon, a protected area in Rio de Janeiro, southeastern Brazil. Data were obtained in monthly surveys in points along a continuous transect, between August 2008 and July 2009, and 21 ad libitum observations. In total, 174 species were listed, including 121 land birds and 53 waterbirds. Of these, 11 are considered threatened at regional level. Waterbird richness was significantly higher in the dry season (April to September) than in the rainy season (October to March), whereas land bird richness remained constant. However, land bird richness varied throughout the year, with the highest value in February 2009 (77 species) and the lowest in May 2009 (41 species). The species listed account for 23% of the total of 745 bird species listed for Rio de Janeiro, and for 49% of 108 waterbirds recorded for the state.
文摘A bryophyte propagule bank serves as a source for population maintenance and survival, and many factors can influence these propagules’ germination. However, it is unknown how soil depths affect propagules banks, their diversity and abundance overtime in a Neotropical forest. To understand such a paradigm, soil samples were obtained from different depths (0 - 5 cm, 5 - 10 cm, and 10 - 15 cm) at Guajataca State Forest, Puerto Rico;then, they were transferred to the laboratory, cultured, and the amount of gametophytes from propagules present over a seven-month period were measured. Forest soil depth did affect the density of gametophytes. Gametophytes densities augmented overtime for almost all species. Two species mainly influenced the propagule production over time. Also, propagules can have a long-term germination potential for some species.
