The habitat functional response links seasonal third‐order selection to second‐order landscape characteristics

Determining how animals respond to differences in resource availabilities across spatiotemporal extents is critical to our understanding of organism distributions. Variations in resource distribution leading to changes in spatial arrangements across landscapes are indicative of a habitat functional response. Our goal was to assess how resource availabilities influenced both second‐order (i.e., home ranging behavior) and third‐order (i.e., habitat or resource selection) selection by feral pigs (Sus scrofa) in an agricultural landscape. We defined agriculturally based seasons to estimate home range characteristics using autocorrelated kernel density estimation within each season. We then modeled home range size as a function of resource availability (i.e., resource selection analyses) to determine whether individual behaviors were predicted by shifts in home ranging behavior. Both home range analyses and resource selection analyses indicated seasonal differences in selection for agricultural resources as availabilities changed, suggesting second‐ and third‐order selection is mechanistically linked through a habitat functional response.     

Factors influencing pigment production by halophilic bacteria and its effect on brine evaporation rates

The disposal of reject brine, a highly concentrated waste by-product generated by various industrial processes, represents a major economic and environmental challenge. The common practice in dealing with the large amounts of brine generated is to dispose of it in a pond and allow it to evaporate. The rate of evaporation is therefore a key factor in the effectiveness of the management of these ponds. The addition of various dyes has previously been used as a method to increase the evaporation rate. In this study, a biological approach, using pigmented halophilic bacteria (as opposed to chemical dyes), was assessed. Two bacteria, an Arthrobacter sp. and a Planococcus sp. were selected due to their ability to increase the evaporation of synthetic brine. When using industrial brine, supplementation of the brine with an iron source was required to maintain the pigment production. Under these conditions, the Planococcus sp. CP5-4 produced a carotenoid-like pigment, which resulted in a 20% increase in the evaporation rate of the brine. Thus, the pigment production capability of halophilic bacteria could potentially be exploited as an effective step in the management of industrial reject brines, analogous to the crystallizer ponds used to mine salt from sea water.     

Movement Patterns of Frugivorous Birds Promote Functional Connectivity among Chaco Serrano Woodland Fragments in Argentina

Movement patterns of frugivorous birds may be altered in anthropogenically fragmented landscapes, with possible consequences for seed dispersal and plant recruitment. We studied the movement patterns and functional connectivity of six frugivorous bird species (Colaptes melanochloros, Thraupis bonariensis, Pitangus sulphuratus, Saltator aurantiirostris, Turdus amaurochalinus, and Elaenia spp.) in a fragmented Chaco‐woodland landscape in Argentina. We recorded the directions of bird movements (arrivals and departures) and whether their destination was oriented toward a specific neighboring fragment. We evaluated the movement rates, distance of interpatch movement, and functional connectivity within the landscape for the six bird species. We applied a novel approach, graph theory, to represent bird movement patterns in the landscape and the functional connections among fragments for each bird species. Bird movements were recorded at point‐count stations established along the edges of each fragment. The directions of arrival and departure movements from and to neighboring fragments revealed complex movement patterns. However, the destination of bird movements after leaving the focal fragments was usually concentrated on only a few neighboring fragments of different sizes. Pitangus sulphuratus and T. bonariensis showed larger movement rates and higher functional connectivity (number of graphs and functional area) than the other frugivorous species. The functional connectivity mediated by movement of frugivorous birds may promote seed dispersal of many bird‐dispersed plant species. As forest loss and fragmentation of Chaco subtropical forests increase, understanding the pivotal role of mobile links exerted by avian seed dispersers is vital to maintaining and conserving this unique ecosystem.     

Exploring Vertical Transmission of Bifidobacteria from Mother to Child

Passage through the birth canal and consequent exposure to the mother''s microbiota is considered to represent the initiating event for microbial colonization of the gastrointestinal tract of the newborn. However, a precise evaluation of such suspected vertical microbiota transmission has yet to be performed. Here, we evaluated the microbiomes of four sample sets, each consisting of a mother''s fecal and milk samples and the corresponding infant''s fecal sample, by means of amplicon-based profiling supported by shotgun metagenomics data for two key samples. Notably, targeted genome reconstruction from microbiome data revealed vertical transmission of a Bifidobacterium breve strain and a Bifidobacterium longum subsp. longum strain from mother to infant, a notion confirmed by strain isolation and genome sequencing. Furthermore, PCR analyses targeting unique genes from these two strains highlighted their persistence in the infant gut at 6 months. Thus, this study demonstrates the existence of specific bifidobacterial strains that are common to mother and child and thus indicative of vertical transmission and that are maintained in the infant for at least relatively short time spans.     

Molecular cytogenetic insights into the evolution of the epiphytic genus Lepismium (Cactaceae) and related genera

Changes in chromosome structure and number play an important role in plant evolution. This was investigated in the Neotropical epiphytic cacti: all Lepismium spp. and some related Rhipsalis spp. Both genera have species with disjunct distributions between the paranas of south‐eastern Brazil and north‐eastern Argentina and the yungas forests of the eastern Andes. Karyotypes, fluorescent banding and fluorescence in situ hybridization (FISH) studies using rDNA probes were performed. A time‐calibrated phylogenetic tree was generated to place the karyological information and biogeographical history in an explicit evolutionary context. All species were 2n = 22 and showed symmetrical karyotypes comprising only metacentric chromosomes of similar sizes. The heterochromatin bands were always associated with chromosome satellites coinciding with the location and number of the 18S–5.8S–26S rDNA loci. The 5S rDNA loci had more heterogeneous profiles with one or two loci per haploid genome. Phylogenetic analysis suggested an ancient duplication event of the 5S rDNA loci and more recent post‐speciation translocation and deletion events. These genome restructurings are estimated to have occurred approximately 13.98 Mya in the middle Miocene, after Lepismium and Rhipsalis diverged. The ancestor of Lepismium may have had a similar karyotype to L. lumbricoides and the Rhipsalis spp. (i.e. one 5S locus on chromosome 2). Both genera hypothetically originated in the yungas (north‐eastern Argentina and southern Bolivia), but diversification of the Lepismium crown group probably originated from populations with duplicated 5S loci in the parana forests of south‐eastern Brazil (8.70 Mya in the late Miocene). Two migration events between the yungas and parana forests were suggested to explain the extant distribution of Lepismium spp. These results make Lepismium a model system for the study of the complex chromosomal evolution in plants. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 263–277.     

The influence of nectar production and floral visitors on the female reproductive success of Inga (Fabaceae): a field experiment

Floral morphology, nectar secretion strategies and the contribution of pollinators to the reproductive success of plants provide important clues regarding the levels of generalization or specialization in pollination systems. Anthesis throughout the day and night allows flowers to be visited by diurnal and nocturnal pollinators, promoting generalization or specialization. We studied three species in the diverse tropical genus Inga to: (1) quantify the response of flowers to successive nectar extractions and (2) determine the contribution of diurnal and nocturnal floral visitors to female reproductive success. Inga flowers could be clearly distinguished mainly on the basis of the staminal tube diameter and the quantities of filaments and pollen grains. Successive nectar removals led to a decrease of 60% in the total nectar secretion in I. vera and to increases of 20% in I. ingoides and 10% in I. striata. Despite these differences, the studied Inga spp. exhibited similar patterns of visitation rates and shared diurnal and nocturnal pollinators. Nocturnal pollinators contributed ten times more than diurnal pollinators to the female reproductive success of Inga. Floral morphology, nectar secretion patterns and pollination ecology data suggest an evolutionary trend towards specialization for nocturnal pollinators in Inga spp. with crepuscular or nocturnal flowers. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 230–245.     

Stages of development of the floral secretory disk in Tapirira guianensis Aubl. (Anacardiaceae), a dioecious species

The goal of this study was to analyse possible structural and ultrastructural differences between the secretory disk of male and functionally female flowers of Tapirira guianensis (Anacardiaceae) at different developmental stages. Studies were carried out using light, scanning and transmission electron microscopy. Biochemical tests were employed to determine the proportion of sugars in the nectar of the floral morphotypes: they were found to be similar, both predominantly composed of sucrose. In addition to sugars, lipids and phenolic substances were identified in anthetic flowers; thus, the secretory disk is a mixed secretion gland, also called a sensu lato nectary. During anthesis, granulocrine and eccrine secretory mechanisms occur in both floral morphotypes. After anthesis and fertilization of the functionally female flower, only the lipophilic and phenolic secretion continues until the early stages of fruit development. An intrastaminal secretory disk that produces both nectar and lipids is reported for the first time in Anacardiaceae. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 533–544.     

Geographic and Temporal Trends in Amazonian Knowledge Production

The presence of researchers from Western (i.e., developed world) institutions in Amazonia has frequently been contentious due to fears of ‘scientific imperialism’ or suspicions that they may be exerting undue influence over research agendas and knowledge production to the detriment of local researchers. Such negative perceptions are widespread, but not well substantiated. A more nuanced understanding of these issues requires information on who is conducting research in Amazonia and how knowledge production has changed over time. We performed a bibliometric analysis on Thomson Reuters'ISI Web of Science of all research articles about the Amazon published in three time periods: 1986–1989, 1996–1999, and 2006–2009. We found that the number of articles published and the diversity of countries involved in Amazonian research increased dramatically over the three time periods. The representation of several Amazonian countries—especially Brazil—increased, while the proportion of articles without a single author from an Amazonian country also increased. The results indicate that the research capacity of Amazonian countries has increased, but that leadership of high‐impact projects may still largely reside with researchers from developed countries.