Diversification Process Research Articles

Romania's agricultural workers. Return mobilities and modes of food production

AbstractThis article examines the dynamics of Romanian seasonal migration and its effects on farming and rural areas. We connect labour migration to changes in modes of food production in Western and Eastern Europe. Based on the fieldwork in seven Romanian localities with 40 semi‐structured interviews, we interrogate how seasonal work is shaped by regimes of mobility and economic and social inequalities. Studying the case of Romania's large rural population raises critical questions regarding migration, development and change in rural areas. Answering such questions requires disentangling different categories of seasonal migrants and their return prospects. Looking at how agricultural labour is structured, we examine labour experiences and analyse how migrants' agency operates in precarious contexts. Observing the consequences of seasonal migration and return, we discovered diverging processes of agricultural diversification through entrepreneurialism and a radical change in peasant farming resulting in an increased concentration of farmland.

Geography, climate and shifts in host plants distribution explain the genomic variation in the cactus moth

Landscape heterogeneity and the host plant use are factors suggested to play determinant roles in shaping the evolutionary history of herbivorous insects. However, the role of the reconfiguration of host plants distributions linked to Quaternary climate oscillations as drivers of contemporary population genetic structure is still poorly understood. Here, we formally examine the relative contribution of such factors on intraspecific diversification using the South American cactus moth, Cactoblastis cactorum, an herbivore insect specialized in the use of cacti as host plants. We assessed genomic variation using genome-wide SNPs and mitochondrial data in populations sampled across a broad geographical gradient where moths feed on different cactus species. We integrated demographic simulations and ecological niche modeling into a landscape genomics framework, to test alternative hypotheses of past and current population connectivity for both C. cactorum and its host plants. Regions exhibiting higher genomic diversity were evaluated for congruence with areas where suitable climatic conditions remained stable through time. Our results revealed that past spatial configuration of suitable habitat conditions and shifts of host plants distributions are the factors that better explain the intraspecific diversification. Genomic data also supported the hypothesis that areas of long-term habitat stability served as refugia for C. cactorum, enabling the maintenance of high levels of genetic diversity over time. Overall, our study highlights the importance of integrating inter-specific interactions and their spatio-temporal dynamics to better understand the relative importance of abiotic and biotic factors driving the diversification processes in herbivorous insects with broad geographical and restricted host ranges.

Understanding Regional Branching: Knowledge Diversification via Inventor and Firm Collaboration Networks

The diversification of regions into new technologies is driven by the degree of relatedness to existing capabilities already present in the region. In cases where opportunities for diversification are rather limited, external knowledge that spills over from neighboring regions or from farther away might become an important driver of regional diversification. Despite the relative importance of interregional knowledge flows via collaborative work, we still have a very limited understanding of how collaboration networks across regions might facilitate diversification processes. The present study investigates the diversification patterns of European metropolitan and nonmetropolitan regions into new knowledge domains via technology classes reported in patent applications to the European Patent Office. The findings indicate that externally oriented inventor collaboration networks increase the likelihood that a new technology specialization enters a region, but this external orientation is less important for related diversification than for unrelated diversification. Further, the results demonstrate that interregional collaboration networks help diversification into unrelated technologies if external knowledge sourcing is based on a diverse set of regions and if collaboration is intense within companies located in distinct regions. Within-firm collaborations across regions can compensate for missing related skills in metropolitan and in nonmetropolitan regions alike but are especially important in nonmetropolitan regions. These results provide new evidence about the importance of knowledge flows within multilocation firms in the technological knowledge diversification of regions.

Quantifying expenditure hierarchies and the expansion of global consumption diversity

Economic growth stimulates fundamental changes in consumption patterns as consumers who get rich tend to spread their spending more evenly across a wider variety of goods and services. Comparing cross sectional spending patterns across rich and poor countries, we investigate how this diversification process enables more niche patterns of spending to emerge across the global population of consumers. We use entropy measures to quantify the dispersion of household spending across goods and study how it unfolds as GDP rises. Using a gravity model to study international differences in the relative order of income elasticities, i.e. expenditure hierarchies, we show how this diversification process on the national level is correlated with cultural norms, GDP and income inequality. We find that national expenditure hierarchies are relatively similar across countries among necessities, while they are increasingly unique among luxuries. We further consider how rising affluence tends to generate more niche consumption patterns by examining how rising income is positively correlated with demand heterogeneity and income inequality is negatively correlated with market depth.

An economic analysis of crop diversification and dynamics of cropping pattern in Karnataka, India

The extent and nature of crop diversification and dynamics of cropping pattern in Karnataka state has been analyzed using secondary data collected from different publish sources of Directorate of Economics and Statistics (DES), Bangalore, Karnataka from a period of 1998–99 to 2020–21 (i.e., 23 years). Composite Entropy Index (CEI), double log model and Markov chain analysis were applied to assess the determinants of crop diversification and dynamics of cropping pattern in Karnataka. Results of C.E.I indicates that Kodagu, Dakshina kannada, Yadgir, Udupi and Shivamogga has low crop diversification. Although Karnataka’s crop diversification values show a positive trend but its coefficient value is almost zero. It shows that there is a threat for Karnataka’s crop diversification. The transition probability matrix diagram indicated that although cereals and millet groups occupied a larger share in terms of area under crops, it has a negative net gain in the probability of area retention. Double log model results revealed that the variable like MSP of coarse cereal, percentage of gross irrigated area to net irrigated area, credit inflow in to agricultural sector by the scheduled commercial bank and length of national highways are influencing the crop diversification positively. Therefore, the establishment of fundamental infrastructure, such as reliable irrigation water supply, access to credit, and well-developed transportation networks, is a crucial prerequisite for creating favorable conditions to promote agricultural development and crop diversification. These parameters have been identified as influential factors that shape the nature and extent of crop diversification. By addressing these infrastructure needs, it becomes possible to foster an environment conducive to agricultural growth and facilitate the process of diversification.

Enhancing Adaro’s Transformation Strategy for Business Diversification: The Aluminium Smelter Project

Climate change has become a global concern, and at the 21st Conference of Parties (COP 21) held in Paris in 2015, participating countries agreed to phase out fossil fuels and replace them with renewable energy to achieve Net Zero Carbon Emissions by 2060. Adaro Energy Indonesia (AEI) is a coal (Fossil Fuel) producing company, and the company has prepared a business diversification to a non-coal business. The first step is business diversification for the Aluminium Smelter project. This paper focuses on enhancing Adaro’s transformation strategy for its ongoing business diversification efforts, specifically the Aluminium Smelter Project (Adaro, 2023). It explores the current state of Adaro's transformation, identifies areas for improvement, and provides strategic recommendations to strengthen the transformation strategy. The assessment uses Michael Porter’s Five Forces theory for market analysis, the PESTLE theory for external scanning analysis, and the Organizational Change Management theory for organisation analysis. These theories together are used to capture Adaro’s ideal transformation strategy conditions. SWOT and Resource-Based View (RBV) theories are applied to evaluate existing AEI’s organisational strengths. By comparing the ideal transformation strategy conditions with the current situation of AEI, areas that require enhancement are identified. By refining this strategy, the author is confident that Adaro will successfully navigate the business diversification process and capitalize on the opportunities presented by the Aluminium Smelter Project.

Field sampling of fig pollinator wasps across host species and host developmental phase: Implications for host recognition and specificity.

Previous genetic studies of pollinator wasps associated with a community of strangler figs (Ficus subgenus Urostigma, section Americana) in Central Panama suggest that the wasp species exhibit a range in host specificity across their host figs. To better understand factors that might contribute to this observed range of specificity, we used sticky traps to capture fig-pollinating wasp individuals at 13 Ficus species, sampling at different phases of the reproductive cycle of the host figs (e.g., trees with receptive inflorescences, or vegetative trees, bearing only leaves). We also sampled at other tree species, using them as non-Ficus controls. DNA barcoding allowed us to identify the wasps to species and therefore assign their presence and abundance to host fig species and the developmental phase of that individual tree. We found: (1) wasps were only very rarely captured at non-Ficus trees; (2) nonetheless, pollinators were captured often at vegetative individuals of some host species; (3) overwhelmingly, wasp individuals were captured at receptive host fig trees representing the fig species from which they usually emerge. Our results indicate that wasp occurrence is not random either spatially or temporally within the forest and across these hosts, and that wasp specificity is generally high, both at receptive and vegetative host trees. Therefore, in addition to studies that show chemicals produced by receptive fig inflorescences attract pollinator wasps, we suggest that other cues (e.g., chemicals produced by the leaves) can also play a role in host recognition. We discuss our results in the context of recent findings on the role of host shifts in diversification processes in the Ficus genus.

The distributional impact of structural transformation in rural India: case-study evidence and model-based simulation

The North Indian village of Palanpur has been the subject of close study over a period of six decades from 1957/8 to 2015. Himanshu et al. (2018) document the evolution of the village economy over this period and point to two distinct drivers of growth and distribution of income. An early period of agricultural intensification associated with the green revolution saw an expansion of irrigation and the introduction of new agricultural technologies, leading to rising incomes accompanied by falling poverty and fairly stable, or even declining, income inequality. From about the mid-1970s onwards, a cumulative process of non-farm diversification took hold, and was associated with further growth and poverty decline but also a significant rise in income inequality. Such a process of structural transformation has been observed more widely in rural India. We construct a simple model of a village economy that captures several of the salient features of the Palanpur economy and society, and that is able to reproduce the distributional outcomes observed in the village. Our analysis suggests that while non-farm diversification occurred alongside rising inequality, the counterfactual of no diversification would in fact be associated with an even greater increase. We suggest therefore that non-farm diversification has in fact helped to contain growth in inequality, and has played a particularly pronounced role in reducing poverty. To the extent that other villages in India share features similar to Palanpur, our findings may also hold elsewhere.

Effector modularity promotes functional diversification and evolutionary processes.

Effector modularity promotes functional diversification and evolutionary processes.

Energy security as a source of international competitiveness in new EU member states

Abstract Energy security and international competitiveness are two of the most fiercely discussed topics – especially in the light of the European Union (EU)’s dependence on Russia’s gas, oil, and coal. Both mentioned concepts are of special importance for the so-called EU new member states (EU NMS), which are undergoing the energy diversification process. The main goal of this paper is to analyze how energy security influences the international competitiveness of these countries. The study uses trade theories related to productivity differentials (Ricardian hypothesis) and differences in factor endowments (Heckscher–Ohlin hypothesis) as a basis for our econometric modeling. The results show that relative energy supply as well as physical and human capital relative endowments have a statistically significant impact on international competitiveness of the studied economies.

A new species of Janiralata Menzies, 1951 (Isopoda: Janiridae) from Japanese bathyal waters, with a review of the associations with invertebrates among the species of Janiralata

Abstract Isopods of the genus Janiralata Menzies, 1951 (Asellota: Janiridae) are known from shallow and deep waters of the Northern Hemisphere. Most species are free-living, but some are symbiotic on the surface of other benthic invertebrates. We obtained from three beam- and four otter-trawl hauls 18 Janiralata asellote specimens from the bathyal zone off the Pacific coasts of Tohoku, northeastern Japan. Partial nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene (505 bp) were determined for 16 of the 18 collected specimens. Non-significant genetic differences (< 0.8%) indicated that the individuals were conspecifics. Morphological analysis indicated that all the specimens belonged to a single species, Janiralata planasp. nov. based on the unique morphology of the anterolateral and distolateral projections on the head and pleotelson, surface and lateral margins of the body, antennula article 1, and of the male pleopod 1. Six of the 18 collected specimens were found attached to the surface of an unidentified sea anemone (Hormathiidae), ten to the solasterid starfish Crossaster borealis Fisher, 1906 and two were obtained from the bottom sediment. Three COI haplotypes of the new species were shared by individuals from two neighboring sites, which suggests that genetic isolation occurs on a relatively narrow horizontal scale, although the bathymetric distribution range was rather wide. We describe a case study of the geographic and bathymetric distributions of an asellote species with low dispersal ability and its genetically differentiated populations. Such approach could help elucidate the diversity and distribution of deep-sea organisms and their diversification processes.

Lymphocyte pathway analysis using naturally lymphocyte-deficient fish.

Comparative phylogenetic analyses are of potential value to establish the essential components of genetic networks underlying physiological traits. For species that naturally lack particular lymphocyte lineages, we show here that this strategy readily distinguishes trait-specific actors from pleiotropic components of the genetic network governing lymphocyte differentiation. Previously, three of the four members of the DNA polymerase X family have been implicated in the junctional diversification process during the somatic assembly of antigen receptors. Our phylogenetic analysis indicates that the presence of terminal deoxynucleotidyl transferase is strictly associated with the facility of V(D)J recombination, whereas PolL and PolM genes are retained even in species lacking Rag-mediated somatic diversification of antigen receptor genes.

Phylotranscriptomic analyses reveal deep gene tree discordance in Camellia (Theaceae)

Gene tree discordance is a significant legacy of biological evolution. Multiple factors can result in incongruence among genes, such as introgression, incomplete lineage sorting (ILS), gene duplication or loss. Resolving the background of gene tree discordance is a critical way to uncover the process of species diversification. Camellia, the largest genus in Theaceae, has controversial taxonomy and systematics due in part to a complex evolutionary history. We used 60 transcriptomes of 55 species, which represented 15 sections of Camellia to investigate its phylogeny and the possible causes of gene tree discordance. We conducted gene tree discordance analysis based on 1,617 orthologous low-copy nuclear genes, primarily using coalescent species trees and polytomy tests to distinguish hard and soft conflict. A selective pressure analysis was also performed to assess the impact of selection on phylogenetic topology reconstruction. Our results detected different levels of gene tree discordance in the backbone of Camellia, and recovered rapid diversification as one of the possible causes of gene tree discordance. Furthermore, we confirmed that none of the currently proposed sections of Camellia was monophyletic. Comparisons among datasets partitioned under different selective pressure regimes showed that integrating all orthologous genes provided the best phylogenetic resolution of the species tree of Camellia. The findings of this study reveal rapid diversification as a major source of gene tree discordance in Camellia and will facilitate future investigation of reticulate relationships at the species level in this important plant genus.

How exceptional are the classic adaptive radiations of passerine birds?

We investigated whether celebrated cases of evolutionary radiations of passerine birds on islands have produced exceptional morphological diversity relative to comparable-aged radiations globally. Based on eight external measurements, we calculated the disparity in size and shape within clades, each of which was classified as being tropical or temperate and as having diversified in a continental or an island/archipelagic setting. We found that the distribution of disparity among all clades does not differ substantively from a normal distribution, which would be consistent with a common underlying process of morphological diversification that is largely independent of latitude and occurrence on islands. Disparity is slightly greater in island clades than in those from continents or clades consisting of island and noninsular taxa, revealing a small, but significant, effect of island occurrence on evolutionary divergence. Nonetheless, the number of highly disparate clades overall is no greater than expected from a normal distribution, calling into question the need to invoke key innovations, ecological opportunity, or other factors as stimuli for adaptive radiations in passerine birds.

Domain Architecture Based Methods for Comparative Functional Genomics Toward Therapeutic Drug Target Discovery.

Genes duplicate, mutate, recombine, fuse or fission to produce new genes, or when genes are formed from de novo, novel functions arise during evolution. Researchers have tried to quantify the causes of these molecular diversification processes to know how these genes increase molecular complexity over a period of time, for instance protein domain organization. In contrast to global sequence similarity, protein domain architectures can capture key structural and functional characteristics, making them better proxies for describing functional equivalence. In Prokaryotes and eukaryotes it has proven that, domain designs are retained over significant evolutionary distances. Protein domain architectures are now being utilized to categorize and distinguish evolutionarily related proteins and find homologs among species that are evolutionarily distant from one another. Additionally, structural information stored in domain structures has accelerated homology identification and sequence search methods. Tools for functional protein annotation have been developed to discover, protein domain content, domain order, domain recurrence, and domain position as all these contribute to the prediction of protein functional accuracy. In this review, an attempt is made to summarise facts and speculations regarding the use of protein domain architecture and modularity to identify possible therapeutic targets among cellular activities based on the understanding their linked biological processes.

Skyline Fossilized Birth-Death Model is Robust to Violations of Sampling Assumptions in Total-Evidence Dating.

Several total-evidence dating studies under the fossilized birth-death (FBD) model have produced very old age estimates, which are not supported by the fossil record. This phenomenon has been termed "deep root attraction (DRA)." For two specific data sets, involving divergence time estimation for the early radiations of ants, bees, and wasps (Hymenoptera) and of placental mammals (Eutheria), it has been shown that the DRA effect can be greatly reduced by accommodating the fact that extant species in these trees have been sampled to maximize diversity, so-called diversified sampling. Unfortunately, current methods to accommodate diversified sampling only consider the extreme case where it is possible to identify a cut-off time such that all splits occurring before this time are represented in the sampled tree but none of the younger splits. In reality, the sampling bias is rarely this extreme and may be difficult to model properly. Similar modeling challenges apply to the sampling of the fossil record. This raises the question of whether it is possible to find dating methods that are more robust to sampling biases. Here, we show that the skyline FBD (SFBD) process, where the diversification and fossil-sampling rates can vary over time in a piecewise fashion, provides age estimates that are more robust to inadequacies in the modeling of the sampling process and less sensitive to DRA effects. In the SFBD model we consider, rates in different time intervals are either considered to be independent and identically distributed or assumed to be autocorrelated following an Ornstein-Uhlenbeck (OU) process. Through simulations and reanalyses of Hymenoptera and Eutheria data, we show that both variants of the SFBD model unify age estimates under random and diversified sampling assumptions. The SFBD model can resolve DRA by absorbing the deviations from the sampling assumptions into the inferred dynamics of the diversification process over time. Although this means that the inferred diversification dynamics must be interpreted with caution, taking sampling biases into account, we conclude that the SFBD model represents the most robust approach currently available for addressing DRA in total-evidence dating.

First insight into molecular diversity of interstitial water mites (Acari: Hydrachnidia): a case study from the upper Neretva River in Bosnia and Herzegovina

ABSTRACT Water mites are a diverse but neglected meiofaunal group in interstitial habitats. In this study, water mites were sampled from the hyporheic zone of the upper Neretva river catchment in Bosnia and Herzegovina. In total, 10 obligate subterranean (hyporheobiontic) species were detected. Seven of them, i.e. Atractidespumilus (Szalay, 1946), Frontipodopsis reticulatifrons Szalay, 1945, Lethaxona pygmaea K. Viets, 1932, Paraxonopsis inferorum (Motaş and Tanasachi, 1947), P. vietsi (Motaş and Tanasachi, 1947), Erebaxonopsis brevipes Motaş and Tanasachi, 1947, and one halacarid species, Parasoldanellonyx typhlops K. Viets, 1933, were recorded for the first time for the fauna of Bosnia and Herzegovina. The first DNA barcoding data are provided for three families (Frontipodopsidae, Lethaxonidae, and Hungarohydracaridae), one subfamily (Stygomomoniinae), and 10 species, providing the first basis for a DNA barcode reference library of water mites from the interstitial habitats in South-Eastern Europe. In each of the four species, considered to have a wide Western Palaearctic distribution, i.e., A. pumilus, F. reticulatifrons, Hungarohydracarus subterraneaus, and Stygomomonia latipes, two separate lineages were distinguished. Fossil-calibrated modelling revealed that the diversification and speciation processes within the above-mentioned species started in the Late Miocene (7.3–11.8 Ma).

Policy change in socially embedded local policy processes in São Paulo, 1988–2020

ABSTRACT Policy transformation is a classic theme in policy analysis. Policy models have emphasized the role of actors, coalitions, leadership, and ideas in agenda-setting, the circulation of policy frameworks and solutions, and different mechanisms of gradual institutional change that accumulate in policy trajectories. We sustain that oscillating and incremental policy trajectories also produce policy change during policy implementation, triggered by political competition and partisan politics, the embeddedness of policy communities, and multilevel effects. This theorizing is built from the recent trajectories of social assistance and housing policies in São Paulo. Both trajectories followed incremental processes of expansion and diversification, although with sectoral specificities. These cases show that cumulative positive public policy change may happen even in the face of institutional conditions that the literature considers far from ideal – an extremely fragmented party system, decentralized federalism, and weak bureaucracies and state capacities. Competitive partisan politics reinforced the creation and reanimation of policy innovations under multilevel regulation. Networks of bureaucrats and civil society activists within the relevant policy communities enabled policy replication and reanimation by entering and exiting local administrations depending on their ideological colors.

Genetic diversity and natural selection of Plasmodium vivax reticulocyte invasion genes in Ecuador

BackgroundKnowledge of the diversity of invasion ligands in malaria parasites in endemic regions is essential to understand how natural selection influences genetic diversity of these ligands and their feasibility as possible targets for future vaccine development. In this study the diversity of four genes for merozoite invasion ligands was studied in Ecuadorian isolates of Plasmodium vivax.MethodsEighty-eight samples from P. vivax infected individuals from the Coast and Amazon region of Ecuador were obtained between 2012 and 2015. The merozoite invasion genes pvmsp-1-19, pvdbpII, pvrbp1a-2 and pvama1 were amplified, sequenced, and compared to the Sal-1 strain. Polymorphisms were mapped and genetic relationships between haplotypes were determined.ResultsOnly one nonsynonymous polymorphism was detected in pvmsp-1-19, while 44 nonsynonymous polymorphisms were detected in pvdbpII, 56 in pvrbp1a-2 and 33 in pvama1. While haplotypes appeared to be more related within each area of study and there was less relationship between parasites of the coastal and Amazon regions of the country, diversification processes were observed in the two Amazon regions. The highest haplotypic diversity for most genes occurred in the East Amazon of the country. The high diversity observed in Ecuadorian samples is closer to Brazilian and Venezuelan isolates, but lower than reported in other endemic regions. In addition, departure from neutrality was observed in Ecuadorian pvama1. Polymorphisms for pvdbpII and pvama1 were associated to B-cell epitopes.ConclusionspvdbpII and pvama1 genetic diversity found in Ecuadorian P. vivax was very similar to that encountered in other malaria endemic countries with varying transmission levels and segregated by geographic region. The highest diversity of P. vivax invasion genes in Ecuador was found in the Amazonian region. Although selection appeared to have small effect on pvdbpII and pvrbp1a-2, pvama1 was influenced by significant balancing selection.

Crossing the Rift valley: using complete mitogenomes to infer the diversification and biogeographic history of ethiopian highlands Ptychadena (anura: Ptychadenidae).

The Ethiopian Highlands are considered a biodiversity hotspot, harboring a high number of endemic species. Some of the endemic species probably diversified in situ; this is, for example, the case of a monophyletic clade containing 12 known species of grass frogs of the genus Ptychadena. The different species occur at elevations ranging from 1,500 to above 3,400m and constitute excellent models to study the process of diversification in the highlands as well as adaptations to high elevations. In this study, we sampled 294 specimens across the distribution of this clade and used complete mitogenomes and genome-wide SNP data to better understand how landscape features influenced the population structure and dispersal of these grass frogs across time and space. Using phylogenetic inference, population structure analyses, and biogeographic reconstructions, we found that the species complex probably first diversified on the south-east side of the Great Rift Valley. Later on, species dispersed to the north-west side, where more recent diversification occurred. We further demonstrate that Ptychadena species have dispersed across the Great Rift Valley at different times. Our analyses allowed for a more complete understanding of the contribution of geological events, biogeographic barriers and climatic changes as drivers of species diversification and adaptation in this important biogeographic region.