Variation In Number Of Species Research Articles

Ecological status and spatial extent of non-native shrubs Lantana camara L. and Ageratina adenophora Sprengel in the forest communities of western Himalaya

This research elucidates the ecological status and spatial extent of two non-native invasive species, Lantana camara L. and Ageratina adenophorum Sprengel, within dominant forest communities across an altitude gradient in the western Himalayan region. The study, conducted from 2017 to 2019 in the Nainital district of Kumaun Himalaya, focused on four forest communities; Sal, Chir-pine, Banj-oak, and Mixed-oak, spanning an altitudinal range from 300 to 2250 meters. Environmental predictors encompassing topographic, physiographic, and climatic factors, along with species occurrence records, were employed to determine spatial extent. The MaxEnt statistical model, a machine learning algorithm, facilitated the assessment of the spatial distribution of invasives. Results indicate that L. camara has invaded Sal, Chir-pine, and Banj oak forests but has not established in high-elevation mixed-oak stands. Conversely, A. adenophora has invaded Chir-pine, Banj-oak, and Mixed-oak stands but has not been observed in low-altitude Sal forests. No significant variation in species number, diversity, or distribution pattern along the elevation gradient was observed for either species. Spatial assessment using MaxEnt revealed an estimated area of 380 km² for A. adenophora and 285 km² for L. camara. The study highlights the mid-altitude zone as the most vulnerable to species invasion. This scientific inquiry contributes valuable insights for the conservation of non-native shrubs, offering guidance for effective, species-specific conservation and management strategies in the Himalayan region.

Habitat Utilization and Feeding Pattern of Avifauna in Goalpara College Campus, Goalpara, Assam, India

A study on habitat utilization and feeding pattern of avian diversity was carried out in Goalpara College campus of Goalpara district, Assam. A total of 44 species of birds belonging to 30 families were recorded and studied. Based on food type eaten, the birds were categorized into seven categories. Variation in number of species based on food type was tested and variation was found insignificant (p=2.22). However, insectivorous category was found to be dominating over other categories. The habitat selection of avian fauna of the campus was also analyzed, and the habitat type H-1 was found to be species rich (38.6%, 17 species) and H-4 type as species-poor habitat (13.6%, 6 species). The order of habitats in terms of species richness is H-1(38.6%, 17 species) > H-3 (27.3%, 12 species) > H-2 (20.5%, 9 species) > H-4 (13.6%, 6 species). The Shannon index for the recorded species showed highest diversity in the habitat type H-1 (H’=1.053) and least diversity in habitat type H-4 (H’=0.577). The study indicates that the college campus provide a suitable habitat for the birds species providing food materials, water, shelters, roosting, and nesting sites. Since birds play a vital role in the ecosystem as pollinators, seed dispersers and help in regeneration of flowering plants and thereby reforestation, therefore an attempt has been made to determine the avian diversity of the college campus with special reference to their habitat utilization and feeding pattern. This study highlights the role of modified habitats to maintain the urban biodiversity. This study will provide base line information on avifauna of Goalpara town which could be useful for management of their habitats.

Diversity Analysis and Dry Preservation of Butterflies to Understand Future Strategies in CGU Campus, Odisha, India

Butterflies are excellent markers of environmental evaluation because of their sensitive nature and changes in butterflies’ habitats have a direct impact on them. Increasing urbanization may have catastrophic repercussions on both regional and global levels by causing habitat loss. The current study was conducted from January to April during the morning and afternoon hours of the year, 2023 in the State of Odisha within the campus of C.V Raman Global University to explore the diversity of butterflies and ways towards the sustainable maintenance of butterfly species over the long term. Altogether, 108 individuals and 17 butterfly species belonging to 3 families, Nymphalidae, Pieridae, and Papilionidae were documented. Nymphalidae, one of the three families, was found to have the most diverse number of species, 11 (64.72%), followed by Pieridae with 4 species (23.52%), and Papilionidae with only 2 species (11.76%). An index of diversity (H’) for the butterfly family Nymphalidae is 1.944327 and Evenness is 0.810847 indicating the highest level of diversity and for the Papilionidae family Shannon diversity index is 0.529706 and Evenness is 0.764205 which shows the lowest level of diversity. The current study also suggests sustainable maintenance steps for the butterfly population on the campus.

Arthropod communities and drivers of their species diversity and composition in caves

Understanding the drivers of diversity patterns in ecological communities remains a major challenge in ecology. Moreover, few studies have considered invertebrate or subterranean communities and little is known about which factors are responsible for structuring arthropod communities in caves. In this study we: assessed the abundance, richness, and composition of arthropod communities from eight caves located in Banat and Mehedinti region, Romania; and determined whether altitude, cave physical characteristics (temperature, relative humidity, light intensity) and features (cave extension, hight, width, heterogeneity, substrate (wall versus floor)) influence cave arthropod communities along the horizontal development of the cave (i.e. from the cave entrance, through the intermediate zone, to the aphotic zone). assessed the abundance, richness, and composition of arthropod communities from eight caves located in Banat and Mehedinti region, Romania; and determined whether altitude, cave physical characteristics (temperature, relative humidity, light intensity) and features (cave extension, hight, width, heterogeneity, substrate (wall versus floor)) influence cave arthropod communities along the horizontal development of the cave (i.e. from the cave entrance, through the intermediate zone, to the aphotic zone). Overall, 89 species were found, of which three were obligate subterranean dwellers and 17 were endemic species. Species abundance distributions showed evident variation in species numbers among cave zones and between the wall and floor substrate. Species abundance was influenced by cave extension, relative humidity and light intensity. Species richness was related to cave extension while relative humidity and cave heterogeneity affected the species diversity. The results also indicated differences in species abundance, richness and diversity among cave zones and between substrate types. The arthropod community structure and composition was determined by altitude, relative humidity, temperature and substrate. The floor and wall substrate had different species composition while the species composition of the three cave zones largely overlapped. We conclude that several biotic and abiotic factors explain the diversity and composition of cave arthropods communities and that our results may be relevant to other types of island-like habitats.

Moths and butterflies on alien shores: Global biogeography of non‐native Lepidoptera

AbstractAimLepidoptera is a highly diverse, predominantly herbivorous insect order, with species transported to outside their native range largely facilitated by the global trade of plants and plant‐based goods. Analogous to island disharmony, we examine invasion disharmony, where species filtering during invasions increases systematic compositional differences between native and non‐native species assemblages, and test whether some families are more successful at establishing in non‐native regions than others.LocationHawaii, North America, Galapagos, Europe, South Africa, South Korea, Japan, Nansei Islands, Ogasawara Islands, Australia, New Zealand.TaxonLepidoptera.MethodsWe compared numbers of non‐native, unintentionally introduced Lepidoptera species with the land area of 11 regions worldwide. Differences among native and non‐native assemblages in the distribution of species among families were investigated using ordination analysis. We tested whether invasion disharmony is explained by propagule pressure (proxied by species richness in border interceptions) and if families were associated with specific trade commodities.ResultsIn total, 741 non‐native Lepidoptera species, accounting for 0.47% of the global diversity of lepidopterans, are established in at least one of the 11 regions. Crambidae, Pyralidae, Tineidae and Gracillariidae were particularly successful invaders, whereas the two most species‐rich families, Erebidae and Geometridae, were under‐represented among non‐native Lepidoptera. Much of the variation in species numbers in the native, and less so in the non‐native assemblages could be attributed to land area. Although native assemblages were similar among nearby regions, non‐native assemblages were not, suggesting geography had little effect on invasion disharmony. Comparison of established with intercepted species revealed that macromoth families were generally under‐represented in establishments, whereas several micromoth families were under‐represented in interceptions. This discrepancy may relate to greater detectability of larger species or high propagule pressure via associations with specific invasion pathways.Main conclusionsInvasion disharmony in Lepidoptera appears to be driven by processes unrelated to the success of native assemblages. While native assemblages developed through long‐term evolutionary radiation, the composition of non‐native assemblages is driven by differential invasion pathways and traits affecting the establishment of founder populations that vary among families.

Low Diversity of Human Variation Despite Mostly Mild Functional Impact of De Novo Variants.

Non-synonymous Single Nucleotide Variants (nsSNVs), resulting in single amino acid variants (SAVs), are important drivers of evolutionary adaptation across the tree of life. Humans carry on average over 10,000 SAVs per individual genome, many of which likely have little to no impact on the function of the protein they affect. Experimental evidence for protein function changes as a result of SAVs remain sparse – a situation that can be somewhat alleviated by predicting their impact using computational methods. Here, we used SNAP to examine both observed and in silico generated human variation in a set of 1,265 proteins that are consistently found across a number of diverse species. The number of SAVs that are predicted to have any functional effect on these proteins is smaller than expected, suggesting sequence/function optimization over evolutionary timescales. Additionally, we find that only a few of the yet-unobserved SAVs could drastically change the function of these proteins, while nearly a quarter would have only a mild functional effect. We observed that variants common in the human population localized to less conserved protein positions and carried mild to moderate functional effects more frequently than rare variants. As expected, rare variants carried severe effects more frequently than common variants. In line with current assumptions, we demonstrated that the change of the human reference sequence amino acid to the reference of another species (a cross-species variant) is unlikely to significantly impact protein function. However, we also observed that many cross-species variants may be weakly non-neutral for the purposes of quick adaptation to environmental changes, but may not be identified as such by current state-of-the-art methodology.

Drivers of global Scolytinae invasion patterns.

Biological invasions are affected by characteristics of invading species, strength of pathway connectivity among world regions and habitat characteristics of invaded regions. These factors may interact in complex ways to drive geographical variation in numbers of invasions among world regions. Understanding the role of these drivers provides information that is crucial to the development of effective biosecurity policies. Here we assemble for the first time a global database of historical invasions of Scolytinae species and explore factors explaining geographical variation in numbers of species invading different regions. This insect group includes several pest species with massive economic and ecological impacts and these beetles are known to be accidentally moved with wood packaging in global trade. Candidate explanatory characteristics included in this analysis are cumulative trade among world regions, size of source species pools, forest area, and climatic similarity of the invaded region with source regions. Species capable of sib-mating comprised the highest proportion on nonnative Scolytines, and these species colonized a higher number of regions than outbreeders. The size of source species pools offered little power in explaining variation in numbers of invasions among world regions nor did climate or forest area. In contrast, cumulative trade had a strong and consistent positive relationship with numbers of Scolytinae species moving from one region to another, and this effect was highest for bark beetles, followed by ambrosia beetles, and was low for seed and twig feeders. We conclude that global variation in Scolytine invasions is primarily driven by variation in trade levels among world regions. Results stress the importance of global trade as the primary driver of historical Scolytinae invasions and we anticipate other hitchhiking species would exhibit similar patterns. One implication of these results is that invasions between certain world regions may be historically low because of past low levels of trade but future economic shifts could result in large numbers of new invasions as a result of increased trade among previously isolated portions of the world. With changing global flow of goods among world regions, it is crucial that biosecurity efforts keep pace to minimize future invasions and their impacts.

KEANEKARAGAMAN JENIS SEMUT (formicidae) DI KAWASAN HUTAN GUNUNG SELINDUNG DESA TWI MENTIBAR KECAMATAN SELAKAU KABUPATEN SAMBAS

Ants is a one of the biotic components in the forests of Kalimantan, this animal has a number of diverse species. This study aims to record and analyze the diversity of ant species in the area of Gunung Selindung of Twi Mentibar Village in Selakau Sub-District of Sambas Regency. The research method was purposive sampling where the placement of traps was done intentionally according to the presence of ants in three forest cover areas that is in open, medium and closed fores areas, divided into two area namely terestrial strata and arboreal. The results showed that there where nine species of ants (Formicidae) found in the Mount Selindung Forest area, namely black field ants (Formica sp), rang-rang (Oecophyllasp) pudak ant (Tapinoma melanocep), the black garden ant (Lasius niger), black ant (Dolichoderus teracicus), yellow crazy ant (Anoplolepis gracilipes), jumping ant (Harpagenethas Saltator), honey ant (Myrmecocystus sp), and sembadak ant (Odontomachus sp). The diversity index of the terestrial (H '), of three types of forest cover areas, namely closed areas (H' = 0.63), moderate (H '= 0.76), and open area strata(H '= 0.73), all still showes the value of low species diversity; the species diversity index int the arboreal (H '), of the three types of forest cover areas namely closed area (H '), moderate (H = 0.61), and open area (H '= 0.55) all still showes the value of low species diversity. keyword: Ants, protected fores, , species diversity, Twi Mentibar Village

Maximum Likelihood Estimation of Species Trees from Gene Trees in the Presence of Ancestral Population Structure.

Though large multilocus genomic data sets have led to overall improvements in phylogenetic inference, they have posed the new challenge of addressing conflicting signals across the genome. In particular, ancestral population structure, which has been uncovered in a number of diverse species, can skew gene tree frequencies, thereby hindering the performance of species tree estimators. Here we develop a novel maximum likelihood method, termed TASTI (Taxa with Ancestral structure Species Tree Inference), that can infer phylogenies under such scenarios, and find that it has increasing accuracy with increasing numbers of input gene trees, contrasting with the relatively poor performances of methods not tailored for ancestral structure. Moreover, we propose a supertree approach that allows TASTI to scale computationally with increasing numbers of input taxa. We use genetic simulations to assess TASTI’s performance in the three- and four-taxon settings and demonstrate the application of TASTI on a six-species Afrotropical mosquito data set. Finally, we have implemented TASTI in an open-source software package for ease of use by the scientific community.

Ontogeny of the specificity of gonadotropin receptors and gene expression in carp.

The pituitary gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), are the principle endocrine drivers of reproductive processes in the gonads of jawed vertebrates. Canonically, FSH recruits and maintains selected ovarian follicles for maturation and LH induces the stages of germinal vesicle breakdown and ovulation. In mammals, LH and FSH specifically activate cognate G-protein-coupled receptors that affect the proteins involved in steroidogenesis, protein hormone synthesis, and gametogenesis. This dual-gonadotropin model also exists in some fish species, but not in all. In fact, due to their diverse number of species, extended number of ecological niches, and remarkably flexible reproductive strategies, fish are appropriate as models to understand the co-evolution of gonadotropins and their receptors. In this study, we cloned and characterized the expression profile over the final stages of ovarian maturation of carp (Cyprinus carpio) LHCGR and FSHR. Expression of both gonadotropin receptors increased in the later stage of early vitellogenesis, suggesting that both LH and FSH play a role in the development of mature follicles. We additionally tested the activation of cLHCGR and cFSHR using homologous and heterologous recombinant gonadotropins in order to gain insight into an evolutionary model of permissive gonadotropin receptor function. These data suggest that carp (Cyprinus carpio) gonad development and maturation depends on a specific gonadotropin profile that does not reflect the temporally distinct dual-gonadotropin model observed in salmonids or mammals, and that permissive gonadotropin receptor activation is a specific feature of Ostariophysi, not all teleosts.

Diagnóstico ecológico, formulación e implementación de estrategias para la restauración de un bosque seco tropical interandino (Huila, Colombia)

El diagnóstico ecológico regional es fundamental para planificar procesos de restauración ecológica (RE), especialmente en ecosistemas poco conocidos y amenazados como el Bosque Seco Tropical (bs-T). A partir del diagnóstico ecológico de un bs-T en el departamento del Huila, Colombia, se formuló, implementó e inició el monitoreo de seis estrategias para su restauración. Para los escenarios de restauración se identificaron las barreras a la regeneración natural y sus facilitadores, los ecosistemas de referencia y las especies clave. Con esta información se formularon seis estrategias de restauración: i) nucleación en pastizales abiertos con núcleos entre 2x2 m y 32x32 m con variación en el número de especies (3–30), número de individuos (9–196), ensambles de especies (1–4) y manejo del suelo, ii) siembra bajo árboles nodriza en pastizales arbolados con 37 individuos de seis especies, iii) siembra bajo agrupaciones de árboles con 57 individuos de once especies, iv) ampliación de borde de bosques y arbustales con fajas de 10x5 m con 17 individuos de cinco especies, v) enriquecimiento en arbustales y bosques en módulos hexagonales monoespecíficos de siete individuos, y vi) restauración espontánea. La siembra total fue de 54 300 individuos con mayor esfuerzo en la nucleación de 32x32 m con 159 réplicas y 21 676 individuos. El monitoreo a largo plazo permitirá evaluar el desarrollo de trayectorias sucesionales acorde con las referencias y determinar el costo efectividad de las estrategias. Este proceso metodológico de diagnóstico ecológico, formulación, implementación y monitoreo de estrategias puede servir como guía importante para la RE del bs-T en otras localidades.

Diversity of Green Seaweeds along the Coast of Karachi

The seasonal diversity and species richness of marine benthic green algae or seaweeds belonging to the phylum Chlorophyta found at Karachi coast were studied in present study. At Karachi coast the green seaweeds occupy a large area and show great variation in their types and species composition. Total 48 green species of seaweeds belong to 9 genera 7 families 6 orders and 2 classes were collected from intertidal areas of Karachi coast (Buleji, Manora, Hawks Bay, Sandspit, Korangi Creek, Cape Monze, Paradise Point, Pacha and Rehri) during January 2009 to December 2009. Total 500 individuals examined, representing 9 genera i.e., Enteromorpha, Ulva, Chaetomorpha, Bryopsis, Codium, Caulerpa, Halimeda, Udotea, Valoniopsis. From the present observation it is clear that Buleji and Manora are the more productive sites as compared to other sites. There was great variation in number of species in different genus. All these forty eight studied species were found attached and in epilithic condition. There is much monthly variation found in species richness at Karachi coast during study period. The present study showed that the high values of species richness and abundance of seaweeds were observed during winter season (December to February).

Comparative Metabolomics of Mycoplasma bovis and Mycoplasma gallisepticum Reveals Fundamental Differences in Active Metabolic Pathways and Suggests Novel Gene Annotations.

Mycoplasmas are simple, but successful parasites that have the smallest genome of any free-living cell and are thought to have a highly streamlined cellular metabolism. Here, we have undertaken a detailed metabolomic analysis of two species, Mycoplasma bovis and Mycoplasma gallisepticum, which cause economically important diseases in cattle and poultry, respectively. Untargeted gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry analyses of mycoplasma metabolite extracts revealed significant differences in the steady-state levels of many metabolites in central carbon metabolism, while 13C stable isotope labeling studies revealed marked differences in carbon source utilization. These data were mapped onto in silico metabolic networks predicted from genome wide annotations. The analyses elucidated distinct differences, including a clear difference in glucose utilization, with a marked decrease in glucose uptake and glycolysis in M.bovis compared to M.gallisepticum, which may reflect differing host nutrient availabilities. The 13C-labeling patterns also revealed several functional metabolic pathways that were previously unannotated in these species, allowing us to assign putative enzyme functions to the products of a number of genes of unknown function, especially in M.bovis. This study demonstrates the considerable potential of metabolomic analyses to assist in characterizing significant differences in the metabolism of different bacterial species and in improving genome annotation. IMPORTANCE Mycoplasmas are pathogenic bacteria that cause serious chronic infections in production animals, resulting in considerable losses worldwide, as well as causing disease in humans. These bacteria have extremely reduced genomes and are thought to have limited metabolic flexibility, even though they are highly successful persistent parasites in a diverse number of species. The extent to which different Mycoplasma species are capable of catabolizing host carbon sources and nutrients, or synthesizing essential metabolites, remains poorly defined. We have used advanced metabolomic techniques to identify metabolic pathways that are active in two species of Mycoplasma that infect distinct hosts (poultry and cattle). We show that these species exhibit marked differences in metabolite steady-state levels and carbon source utilization. This information has been used to functionally characterize previously unknown genes in the genomes of these pathogens. These species-specific differences are likely to reflect important differences in host nutrient levels and pathogenic mechanisms.

Variación espacial en número de especies, abundancia y diversidad de peces en las Bahías de Huatulco, Oaxaca, México

Coral reef fish may adapt to their habitat characteristics, and the particular system intrinsic factors, may cause different fish compositions and structures. The present study aimed to determine the variation in number of species, abundance and diversity of fish communities in Huatulco bays of San Agustin, Riscalillo, Chachacual, Cacaluta, Maguey, Organo, Violín and La Entrega, from Oaxaca, Mexico. Fish communities were characterized between January 2009 and December 2010, with the use of visual census techniques. A total of 351 transects (10 x 2.5 m) were made, and for each one we analyzed the ichthyofauna species number, abundance and diversity. The analysis showed that for all variables, the highest values corresponded to Maguey, La Entrega, Órgano and Violín bays, while the lowest values corresponded to the San Agustín, Riscalillo, Chachacual and Cacaluta bays. The study identified significant differences in diversity (Kruskal-Wallis=18.71, P= 0.0091), and in the composition and structure of fish communities in the bays (ANOSIM= 0.278, P= 0.001). We observed a relationship between the number of fish species and number of coral species (Spearman=0.591, P< 0.05), while no relationship was found between the coral reef area and the number of fish species or their abundances. The number of coral species and the patchy arrangement of the coral cover created habitats that are structurally more complex, which affects the number of fish species. In areas with developed tourist infrastructure, recreational aquatic activities were found to affect the ichthyofauna behavior, abundance and diversity. The new information of this study may contribute to create and improve management, conservation and protection strategies for this important area as a whole interconnected complex.

Contribution of Nutrient Diversity and Food Perceptions to Food and Nutrition Security Among Smallholder Farming Households in Western Kenya: A Case Study.

Sub-Saharan Africa is the only region in the world where hunger is prevalent in over one-third of the population, with smallholder farming households, producers of over 80% of Africa's food, facing both calorie and micronutrient deficiencies. With agricultural systems serving as the main source of all nutrients, little is known about the extent to which agricultural diversity in different seasons can meet macro- and micronutrient needs in rural Africa. Linkages between nutrient diversity and food species were investigated. A case study was conducted in Western Kenya to assess the seasonal nutrient diversity, seasonal nutrient accessibility levels, and food perceptions in 30 smallholder farms, 7 markets, and among 97 focus group discussion participants, respectively. All present food plant and animal species were inventoried and assigned to 1 of the 7 major Food and Agriculture Organization-defined food groups. Based on 2 macronutrients and 5 micronutrients, dendrogram-based nutrient functional diversity metrics were calculated. On-farm and market food species offered all 7 macro- and micronutrients under investigation, regardless of seasonal variation in species numbers. Although there were varying seasonal nutrient accessibility levels in markets, farms were especially effective in readily availing 4 of the 7 nutrients. However, the main food shortage months coincided only with maize shortage, but a diversity of local foods, deemed to be of low cultural and culinary preferences, were available. Nutrition education on the importance of a diversity of local foods in meeting dietary needs, thus stimulating the demand side, can contribute to achieving year-round household food security.

What explains patterns of biodiversity across the Tree of Life?: New research is revealing the causes of the dramatic variation in species numbers across branches of the Tree of Life.

A major challenge in biology is to explain why some groups have thousands or millions of species whereas others have few. Here, I review the causes of this variation. New studies reveal that higher species numbers in many major groups are explained by higher diversification rates (and traits that accelerate these rates). These traits span most of biology (e.g. genomics, ecology, morphology). Rather than simply testing individual traits, research should now focus on comparing how much variation in diversification rates is explained by different types of traits. For example, is local-scale ecology (e.g. microhabitat, diet) more important than large-scale climate (e.g. occurring in tropical vs. temperate regions)? Are traits based on particular values (e.g. smaller body sizes) more important than those based on rates of change (e.g. faster size evolution)? I review recent results on the relative importance of different traits for driving diversification, and present a framework for future research.

LATERAL BRANCHING OXIDOREDUCTASE acts in the final stages of strigolactone biosynthesis in Arabidopsis

Strigolactones are a group of plant compounds of diverse but related chemical structures. They have similar bioactivity across a broad range of plant species, act to optimize plant growth and development, and promote soil microbe interactions. Carlactone, a common precursor to strigolactones, is produced by conserved enzymes found in a number of diverse species. Versions of the MORE AXILLARY GROWTH1 (MAX1) cytochrome P450 from rice and Arabidopsis thaliana make specific subsets of strigolactones from carlactone. However, the diversity of natural strigolactones suggests that additional enzymes are involved and remain to be discovered. Here, we use an innovative method that has revealed a missing enzyme involved in strigolactone metabolism. By using a transcriptomics approach involving a range of treatments that modify strigolactone biosynthesis gene expression coupled with reverse genetics, we identified LATERAL BRANCHING OXIDOREDUCTASE (LBO), a gene encoding an oxidoreductase-like enzyme of the 2-oxoglutarate and Fe(II)-dependent dioxygenase superfamily. Arabidopsis lbo mutants exhibited increased shoot branching, but the lbo mutation did not enhance the max mutant phenotype. Grafting indicated that LBO is required for a graft-transmissible signal that, in turn, requires a product of MAX1. Mutant lbo backgrounds showed reduced responses to carlactone, the substrate of MAX1, and methyl carlactonoate (MeCLA), a product downstream of MAX1. Furthermore, lbo mutants contained increased amounts of these compounds, and the LBO protein specifically converts MeCLA to an unidentified strigolactone-like compound. Thus, LBO function may be important in the later steps of strigolactone biosynthesis to inhibit shoot branching in Arabidopsis and other seed plants.

Plant Diversity and Floristic Composition of Three Forest Types in Mata Vaishno Devi Forest of Jammu and Kashmir, Western Himalaya, India

An investigation was carried out to study the plant diversity and floristic composition on three forest types namely, mixed - broadleaved forest (800-1000m), Pinus roxburghii forest (1400-1600m) and Quercus leucotrichophora forest (2000-2200m) in Mata Vaishno Devi forest of J and K, Western Himalaya. Total 58 families, 102 genera and 116 species were recorded in three forests along the altitudes. Mixed- broadleaved forest represented a total of 29 families with 42 genera and 48 species. Pinus roxburghii forest was comprised of 30 families with 44 genera and 45 species while Quercus leucotrichophora forest also represented 30 families with 41 genera and 42 species. It revealed almost similar number of families and genera with little variation in number of species at different forests along altitudes. Cassia fistula, Acacia catechu, Acacia modesta, Bauhinia variegata, and Dalbergia sissoo were the dominant tree species in mixed- broadleaved forest at lower altitude, Pinus roxburghii and Bauhinia variegata were dominant in Pinus roxburghii forest at middle altitude and Quercus leucotrichophora, and Rhododendron arboreum were the dominant tree species in Quercus leucotrichophora forest at upper altitude. Asteraceae, Euphorbiaceae, Poaceae, Acanthaceae, Lamiacaea, Mimosaceae, Rosaceae, Urticaceae were the dominant families which were present in all the forest types along altitudes. Maximum numbers of species were characterized by clumped distribution. Stand density was higher in Pinus roxburghii forest whereas richness and diversity were higher in the mixed-broadleaf forests.

Intertidal assemblage variation across a subtropical estuarine gradient: How good conceptual and empirical models are?

Variation of intertidal macrobenthic structure at multiple spatial scales is still poorly known in tropical and subtropical estuaries. We have assessed the structural responses of intertidal benthic assemblages, expressed by variation in number of species, abundance and assemblage composition, to key environmental drivers in a subtropical estuary from southern Brazil. We have applied a hierarchical sampling design to assess benthic variation at each of several spatial scales, from meters to kilometers, along a marked estuarine gradient. The hypothesis that many benthic variables vary at the largest spatial scale, corresponding to the salinity gradient, was refuted for number of species but not for total abundance and species composition. However, physiological stress to salinity variation, an important environmental driver in estuaries, could not explain by itself macrobenthic distribution along local intertidal flats. Nutrient, organic matter, photosynthetic pigments contents, pH, grain size, silt–clay content and the redox discontinuity layer also varied at the largest spatial scale acting as confounding factors. Thus, overall distribution patterns of intertidal benthic assemblages resulted from a complex interaction among environmental drivers, including salinity.

The avifauna of Bosque Fray Jorge National Park and Chile's Norte Chico

The avifauna of Chile is relatively depauperate, comprising 469 extant species, of which 213 are terrestrial. However, the Coquimbo Region presents a broad ecological transition from the hyperarid Atacama Desert to the north, and the more mesic Chilean Mediterranean region of central Chile, resulting in relatively high species diversity. Approximately 130 species are found here, 8 of which are endemic to Chile although not to this region. Bosque Fray Jorge National Park is a 9959 ha Biosphere Reserve dominated by matorral habitat and hosting up to 123 bird species. Through avian surveys and banding over nearly a decade we have documented 63 terrestrial species and discerned predictable seasonal and interannual structure to avian assemblages, at least through an extended dry period. Recent studies in the matorral habitats of the park indicate seasonal patterns that fall into 4 patterns: year-round residents, winter visitors, summer breeders, and transients. Short-term banding studies demonstrate co-occurring wintering and breeding cohorts among species of Sierra-finches (Phrygilus) in the park; such assemblages and dynamics are reminiscent of North American Mediterranean avian assemblages and pose interesting ecological comparisons. In this period of surveys there appears to have been a gradual transition of the avifauna that may be a response to anthropogenic influence and/or climate change. Research on the foraging behavior of 2 insectivorous species indicate that one of these is convergent on better-known North American taxa while the other clearly is not; these efforts suggest useful avenues for further comparative research. A remarkable coevolutionary association between the Chilean Mockingbird (Mimus thenca) and endoparasitic mistletoes (Tristerix) provides insight into potential convergent ecologies in desert regions with different evolutionary histories.Less than 1% of the park comprises temperate forest remnants that subsist due to extensive water input from fog. Research in these remnants has emphasized the role of habitat fragmentation on avian assemblage composition and on reproductive ecology by forest-dependent species. The avifauna here comprises a subset of that found in intact Valdivian rainforest to the south, and forest remnant size alone explains over 90% of the variation in species numbers. One species has been particularly well studied; the Thorn-tailed Rayadito (Aphrastura spinicauda) is more abundant and has higher nestling survival in larger fragments. We summarize other work on stress responses and variation in song structure in this species. Finally, the role of birds in tree recruitment here has important implications in the face of a recent history of reduction in sizes of forest remnants; numerous birds consume the fruit of the dominant tree, olivillo (Aextoxicon punctatum), but they fail to promote successful recruitment because they defecate viable seeds in locations that provide poor survival of seedlings.Ornithological research in Chile is undergoing a modest renaissance, and while dryland avifaunas are characterized more by what is not known and has yet to be studied than by actual ecological understanding, they provide a baseline for many exciting studies ranging from natural history to the role of migration to comparative dynamics of independent lineages in North and South America.