An elementary industry of the chimpanzees in the Okorobikó mountains,Rio Muni (Republic of Equatorial Guinea), West Africa

Sticks are described which have been shaped and used by chimpanzees of the subspeciesPan troglodytes troglodytes in the mountainous region of Okorobikó in central Rio Muni (West Africa). References are also made to the utilization of these sticks for the obtaining of termites of the speciesMacrotermes mülleri andMacrotermes sjöstedt. It is indicated that in Rio Muni this elemental industry is known only to some of the groups of these pongids, inhabiting moreover areas relatively close to each other. Also presented is a new map indicating in summary manner the distribution of the principal elemental industries known to chimpanzees in the wild.     

An extraordinary new rheophyte in the genus Leptactina (Rubiaceae, Pavetteae) from Rio Muni (Equatorial Guinea)

A distinctive new species of Rubiaceae from Rio Muni, Equatorial Guinea, is described and illustrated. Leptactina rheophytica is the only rheophyte known in the genus. Its diagnostic characters are elucidated, its taxonomic affinities are discussed, and notes on its conservation status are provided.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 109–113.     

Karyotype differentiation in Chromaphyosemion killifishes (Cyprinodontiformes, Nothobranchiidae): patterns, mechanisms, and evolutionary implications

Chromaphyosemion killifishes are a karyotypically highly diverse group of small, sexually dimorphic fishes living in rainforest rivulets in tropical West and Central Africa. In the present study, we used various chromosome banding and staining techniques to analyse the karyotypes of 13 populations representing seven described species ( Chromaphyosemion loennbergii , Chromaphyosemion punctulatum , Chromaphyosemion splendopleure , Chromaphyosemion volcanum , Chromaphyosemion malumbresi , Chromaphyosemion melanogaster , Chromaphyosemion bitaeniatum ) and two undescribed forms ( Chromaphyosemion cf. lugens , Chromaphyosemion sp. Rio Muni GEMHS00/41). Diploid chromosome numbers (2 n ) and the number of chromosome arms (NF) ranged from 2 n  = 24 in C. malumbresi to 2 n  = 40 in C. bitaeniatum and from NF = 40 in C. volcanum and C. cf. lugens to NF = 54 in one population of C. loennbergii . A tentative XX/XY sex chromosome system was revealed in C. loennbergii , C. melanogaster , C. malumbresi , and Chromaphyosemion sp. Rio Muni GEMHS00/41. Mapping cytogenetic data for all described Chromaphyosemion species onto a recently published mitochondrial DNA phylogeny revealed a complex pattern of chromosomal evolution with several independent reductions of 2 n and independent modifications of NF and nucleolus organizer region phenotypes. Together with the results of preliminary crossing and mate choice experiments, the cytogenetic and molecular phylogenetic data suggest that, contrary to previous hypotheses, chromosomal rearrangements are probably not the most important and certainly not the only factor driving speciation in Chromaphyosemion killifishes.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 143–153.     

Feeding Behaviour and Diet of Chimpanzees (Pan troglodytes troglodytes) in the Okorobikó Mountains of Rio Muni (West Africa)

Some aspects of the nutritional behaviour of the Okorobikó-Matama (Rio Muni, West Africa) chimpanzees have been studied over two periods — from June 1963 to September 1964 and from July 1966 to February 1969. This research totaled 640 h, 119 of which were in sustained contact with the animals. We have compiled a list of 43 plant and two termite species consumed by the chimpanzees. We studied the relative importance of the plants consumed in terms of the four principal biotopes and seasonal cycles, the feeding behavior, the rhythm of activity and chimpanzees' vertical stratification during feeding. We also took into account group dynamics as a function of feeding, communication and polyspecific associations with other primates. We finally compared some aspects of the nutrition of these chimpanzees with that of gorillas living in nearby zones.     

Phylogenetic relationships and phylogeography of the Killifish species of the subgenus Chromaphyosemion (Radda, 1971) in West Africa, inferred from mitochondrial DNA sequences

We have analyzed the phylogenetic relationships of 160 specimens from 88 samples representing all defined species of the African Aplocheiloid subgenus Chromaphyosemion in order to examine the monophyly of this group, the species interrelationships, and to reveal trends in chromosomal evolution and formulate hypotheses about their evolutionary history. The data set comprised 1153 total nucleotides from the mitochondrial 12S rRNA, cytochrome oxidase I, and D-loop. The molecular-based topologies were analyzed by maximum parsimony, maximum likelihood, distance method and Bayesian inference support the monophyly of the subgenus Chromaphyosemion. All populations with ambiguous taxonomic status were assigned to an already described species except A. sp. Rio Muni which corresponds to a still undescribed species. Aphyosemion alpha and A. lugens were in basal position in the different trees that indicate a possible origin of the subgenus Chromaphyosemion in the South Cameroon-North Gabon region. Furthermore, the South Cameroon region (between 2 degrees and 3 degrees of North latitude) that accommodates half of the Chromaphyosemion species is considered to have been a refuge zone during the late quaternary dry events that Africa experienced. Phylogenetic relationships among the subgenus also revealed that chromosomal evolution is complex and should be studied at the intraspecific level.     

The Flight Apparatus of Migratory and Sedentary Individuals of a Partially Migratory Songbird Species

Variations in the geometry of the external flight apparatus of birds are beneficial for different behaviors. Long-distance flight is less costly with more pointed wings and shorter tails; however these traits decrease maneuverability at low speeds. Selection has led to interspecific differences in these and other flight apparatuses in relation to migration distance. If these principles are general, how are the external flight apparatus within a partially migratory bird species shaped in which individuals either migrate or stay at their breeding grounds? We resolved this question by comparing the wing pointedness and tail length (relative to wing length) of migrant and resident European blackbirds (Turdus merula) breeding in the same population. We predicted that migrant blackbirds would have more pointed wings and shorter tails than residents. Contrary to our predictions, there were no differences between migrants and residents in either measure. Our results indicate that morphological differences between migrants and residents in this partially migratory population may be constrained.     

Evolution of nocturnal flight calls in migrating wood-warblers: apparent lack of morphological constraints

Many migratory songbirds produce flight calls that vary, sometimes strikingly, among species in duration, frequency, modulation, and pattern, and little is known about what factors are responsible for this variation. Negative correlations between body mass or bill length and song frequencies are well documented in birds, but no studies have examined these associations for flight calls. We explored relationships between flight call and song frequencies and body mass or bill length in 33 species of wood-warblers. Phylogenetically controlled and uncontrolled analyses showed no significant relationship between body mass or bill length and flight call frequency; however, we found significant differences between flight call and song frequencies and a significant relationship between maximum frequencies of flight calls and songs. Our findings suggest that factors other than body mass and bill length are responsible for variation in flight call frequencies in wood-warblers. We suggest that different ecological and atmospheric properties might play important roles in selection for flight call frequencies.     

Morphologic and genetic differentiation of night monkey (Aotus infulatus, Primates, Platyrrhinians, Cebidae) populations from the right and left banks of Rio Tocantins (Brazil)

The cranial morphology of 28 specimens of night monkeys (genus Aotus) was examined using three-dimensional geometrical morphometrics. New results of the morphological differences between two populations of Aotus infulatus from both banks of the Rio Tocantins are proposed. These morphological results totally agree with the genetic distinction of these populations proposed by Schneider -- and Sampaio --, and probably point out recent rapid evolutive changes for this species. Our morphometric results can be used for taxonomic, but also for medical research, as the susceptibility to malaria of night monkeys is variable between species.     

Postcanine dental form in the mustelidae and viverridae (Carnivora: Mammalia)

This study investigates whether the gross morphology of mustelid and viverrid postcanine dentitions corresponds with differences in diet. For each species, the predominant foods ingested are used to form predictions of dental form and measurements of the carnassial and molar teeth determine the extent of shearing and crushing surfaces on the postcanine teeth. Principal components analysis distinguishes species according to morphological differences in the dentition and these differences are compared with predictions of dental form based on diet. Dietarily specialized species are more likely to be correspondingly specialized in the dentition and species with varied food sources are more likely to possess dental characteristics that are generalized in function. Consumers of foods with high fracture resistance, such as vertebrate tissue and hard-surfaced invertebrates, possess specialized shearing or crushing postcanine teeth. On the other hand, species that consume foods of lesser fracture resistance, such as fruit and soft invertebrates, differ greatly in dental form and are more generalized in dental function. A few species possess postcanine dentitions that do not correspond with diet; the absence of dental-dietary correlation in these species suggests that other factors, such as phylogeny, are important in determining dental form.     

Flight tone of field‐collected populations of Anopheles gambiae and An. arabiensis (Diptera: Culicidae)

Abstract.Laboratory colonies of the human malaria vectors Anopheles gambiae Giles and An. arabiensis Patton have distinct flight tones. If flight tone similarly distinguishes natural populations of these sympatric sibling species, it may play a role in reproductive isolation of swarms that are otherwise behaviourally identical. To assess the fidelity of flight tone differences in natural populations, flight tone was measured in the F1 progeny of mosquitoes of both species captured in western Kenya. Flight tone distributions of wild An . gambiae and An. arabiensis were similar to their laboratory conspecifics. However, interspecies comparisons of flight tone of wild mosquitoes revealed significantly different but overlapping distributions for both sexes. Furthermore, when the effect of body size on flight tone was determined, there was a positive correlation between wing length and flight tone for both sexes of An. gambiae and An. arabiensis , suggesting that mosquito size is a significant variable affecting flight tone. Although these findings diminish any practical benefit of flight tone as a diagnostic tool in species identification, its potential role in pre‐mating species recognition needs further investigation.     

Chilled packing systems for fruit flies (Diptera: Tephritidae) in the sterile insect technique

We evaluated three packing systems (PARC boxes, "GT" screen towers and "MX" screen towers) for the emergence and sexual maturation of sterile fruit flies, at three adult fly densities (1, 1.2 and 1.3 fly/cm2) and three food types. At the lowest density, results showed no significant differences in the longevity and flight ability of adult Anastrepha ludens (Loew) and Anastrepha obliqua Macquart among the three packing systems. Higher densities resulted in a decrease in these parameters. In the evaluation of the three food types, no significant differences were found either on longevity or flight ability of A. ludens. However, the greatest longevity for both sexes A. obliqua was obtained with commercial powdered Mb? and the mix of sugar, protein and corn starch on paper (SPCP) food types. The highest value for flight ability in A. obliqua males was obtained with powdered Mb? and SPCP food types, and for females with Mb? powdered food. Our data indicated that GT and MX screen tower packing systems are an alternative to the PARC boxes, since they were suitable for adult fly sexual maturation without any harm to their longevity or flight ability. The tested foods were equivalent in both fruit fly species, with the exception of the agar type for A. obliqua, which yielded the lowest biological parameters evaluated. Our results contribute to the application of new methods for the packing and release of sterile flies in large-scale programs.     

GEOGRAPHIC GENETIC STRUCTURE IN THE FRANCISCANA DOLPHIN (PONTOPORIA BLAINVILLEI)

The franciscana, Pontoporia blainvillei , is endemic to the South Atlantic coast of South America. The species is of conservation concern because it suffers elevated mortality rates due to incidental captures in fishing nets, and perhaps it is one of the most threatened small cetaceans in this region. Previous morphological and genetic studies have suggested the existence of at least two distinct stocks to the north and south of Santa Catarina Island in Brazil. Fixed differences were found between a sample from Rio de Janeiro and one from Rio Grande do Sul, in southern Brazil. Using 94 sequences of the control region of mitochondrial DNA, we examined the genetic structure of the species. We found no shared haplotypes between Rio de Janeiro and samples from the southern range of the species distribution. However, a phylogenetic analysis suggests that the former population is diphyletic with respect to the southern samples. This suggests that the populations have not been isolated long enough to reach reciprocal monophyly. Furthermore, genetic differentiation is broadly consistent with a simple model of isolation by distance, that therefore appears as an alternative to a model of strict isolation of two stocks. The estimated levels of gene flow are higher among neighboring populations, and decrease as more distant localities are compared. Finally, the molecular data suggest that franciscanas have expanded in Rio de Janeiro.     

Habitat use and nursery evaluation for the longnose stingray Hypanus guttatus (Bloch & Schneider, 1801) using vertebral microchemistry

Here, we use vertebral microchemistry to investigate the habitat use patterns of the longnose stingray Hypanus guttatus in the northern and northeastern regions of Brazil, and to evaluate the existence of potential nurseries of the species. Samples were collected in Maranhão, Rio Grande do Norte and Pernambuco states between 2008 and 2019. Trace element concentrations of Ba:Ca, Mg:Ca, Mn:Ca and Sr:Ca in vertebrae were determined through laser ablation inductively coupled plasma mass spectrometry. We used one-step permutational ANOVAs to evaluate multi and single-element differences in element:Ca ratios among life stages and sexes across and within sites. Element signatures differed among all sites for both single and multi-element settings. However, there were few differences among life stages within sites, except for Mn:Ca between life stages for Maranhão state, and between sexes for Sr:Ca for both Pernambuco and Rio Grande do Norte, and Ba:Ca for Rio Grande do Norte. Furthermore, all multi and single-element analyses across locations were significant and highlight the strong differences by sites. We also performed a nonmetric multidimensional scaling analysis, which demonstrated the strong differences for samples from Rio Grande do Norte and the other two sites. By analysing the lifetime transects of each sample, we observed that there was little variation in all element:Ca ratios within sites. Therefore, we argue that the longnose stingray likely does not display extensive habitat use shifts and fulfils much of its life cycle within each area. Finally, we obtained no evidence of nurseries for any site and suggest this is likely a pattern across the species distribution. Future studies investigating habitat use with samples from larger specimens (disc width > 90 cm, >15 years) are needed to better understand the species habitat use patterns across all size ranges.     

Rank Differences in Ecological Behavior: A Comparative Study of Patas Monkeys (Erythrocebus patas) and Vervets (Cercopithecus aethiops)

One of the central dichotomies in primate behavior is between species in which there are relationships among females that include stable dominance relationships, and those in which the relationships include weak or unstable dominance relationships. This dichotomy has been attributed to differences in food resources, with stable dominance hierarchies occurring in species that feed on usurpable foods. We compared rank-related differences in nonagonistic behaviors considered to be tightly linked to ecology in broadly sympatric vervets (Cercopithecus aethiops) and patas monkeys (Erythrocebus patas), two closely related cercopithecines that are exemplars of this dichotomy, with the expectation that vervets would exhibit stronger rank differences than patas monkeys in these behaviors. Overall, rank explained more than twice as much variation among vervets as among patas monkeys in ranging behavior, activity budgets, and diet. Vervets did not, however, exhibit stronger rank differences when they used Acacia xanthophloea habitat, in which foods are more usurpable, compared to Acacia drepanolobium habitat, in which foods are less usurpable. In Acacia drepanolobium habitat, to which patas are restricted, higher-ranking vervets converged in behavior with patas monkeys to a greater extent than lower-ranking vervets, suggesting that social constraints interfere with the foraging efficiency of lower-ranking vervets even in habitats in which there are fewer opportunities to usurp foods.     

Decoding the ‘zeep’ complex: quantitative analysis of interspecific variation in the nocturnal flight calls of nine wood warbler species (Parulidae spp.)

ABSTRACT

The “zeep” complex consists of nine birds that produce nocturnal flight calls with similar acoustic features. Our inability to distinguish these calls inhibits the acoustic monitoring of these species. We test the hypothesis that flight calls of nine warblers in the “zeep” complex show sufficient acoustic differences to allow differentiation. We investigate divergence in these vocalizations by recording birds held for banding and collecting additional recordings from sound libraries. We used three approaches to compare calls between species: analysis of variance in acoustic properties, discriminant analysis of acoustic properties, and spectrographic cross-correlation. The first approach revealed five species that were different in one or more acoustic properties. The second approach revealed a level of assignment to the correct species (73%) that exceeded levels expected by chance (36%). The third approach revealed calls of seven species to be significantly more similar to conspecific calls than heterospecific calls. Our results suggest the calls of many members of the “zeep” complex exhibit species-specific differences in structure, which may allow differentiation of at least five “zeep” species based on call alone. We advocate for the combined use of these three approaches for the comparison of “zeep” calls in future flight call studies.     

Larval ecomorphology of 13 Libellulidae (Anisoptera, Odonata) of the Middle Rio Doce Valley, Minas Gerais, Brazil.

In the lakes of the Middle Rio Doce, Minas Gerais (MG), two groups of larval Libellulidae are distinguished by preferences of habitat use: one uses mainly aquatic macrophytes and the other uses the bottom substrate. The goal of this work was to verify if there is a morphological distinction between the two groups of species. Thirteen body measures were taken from the larvae and analyzed. No difference was found between the two groups of species regarding the body size, but shape differences were observed for two morphological variables. The species that use mainly macrophytes tend to have larger relative measures of the labium and smaller measures of the abdomen width. Advantages in resource obtainment and in vulnerability to predation are probably the explanations for the morphological divergence among these larval groups.     

Relationship between body size and flying-related structures in Neotropical social wasps (Polistinae,Vespidae, Hymenoptera)

Body size influences wing shape and associated muscles in flying animals which is a conspicuous phenomenon in insects, given their wide range in body size. Despite the significance of this, to date, no detailed study has been conducted across a group of species with similar biology allowing a look at specific relationship between body size and flying structures. Neotropical social vespids are a model group to study this problem as they are strong predators that rely heavily on flight while exhibiting a wide range in body size. In this paper we describe the variation in both wing shape, as wing planform, and mesosoma muscle size along the body size gradient of the Neotropical social wasps and discuss the potential factors affecting these changes. Analyses of 56 species were conducted using geometric morphometrics for the wings and lineal morphometrics for the body; independent contrast method regressions were used to correct for the phylogenetic effect. Smaller vespid species exhibit rounded wings, veins that are more concentrated in the proximal region, larger stigmata and the mesosoma is proportionally larger than in larger species. Meanwhile, larger species have more elongated wings, more distally extended venation, smaller stigmata and a proportionally smaller mesosoma. The differences in wing shape and other traits could be related to differences in flight demands caused by smaller and larger body sizes. Species around the extremes of body size distribution may invest more in flight muscle mass than species of intermediate sizes.     

Nocturnal activity positively correlated with auditory sensitivity in noctuoid moths

We investigated the relationship between predator detection threshold and antipredator behaviour in noctuoid moths. Moths with ears sensitive to the echolocation calls of insectivorous bats use avoidance manoeuvres in flight to evade these predators. Earless moths generally fly less than eared species as a primary defence against predation by bats. For eared moths, however, there is interspecific variation in auditory sensitivity. At the species level, and when controlling for shared evolutionary history, nocturnal flight time and auditory sensitivity were positively correlated in moths, a relationship that most likely reflects selection pressure from aerial-hawking bats. We suggest that species-specific differences in the detection of predator cues are important but often overlooked factors in the evolution and maintenance of antipredator behaviour.     

A comparison of distances flown by different visitors to flowers of the same species

Summary The morphologically complex flowers of Delphinium nelsonii, D. barbeyi, and Ipomopsis aggregata are visited by a wide variety of animals. Visitors to each species range from small insects, such as worker bumblebees and solitary bees, to hummingbirds, and thus span roughly an order of magnitude in body mass and metabolic rate while flying; they also differ in type of food collected and in their efficacy as pollinators. Despite these differences, all the visitors to a given plant species fly similar, short distances between successively visited flowers and plants. There are no significant relationships between mean flight distance and metabolic rate or body mass among the visitors to any plant species. Thus there is no evidence that flight characteristics depend on anything as straightforward as whether flower visitors have high or low energetic requirements.