Mitogenome analyses elucidate the evolutionary relationships of a probable Eocene wet tropics relic in the xerophilic lizard genus Acanthodactylus

AbstractClimate has a large impact on diversity and evolution of the world’s biota. The Eocene–Oligocene transition from tropical climate to cooler, drier environments was accompanied by global species turnover. A large number of Old World lacertid lizard lineages have diversified after the Eocene–Oligocene boundary. One of the most speciose reptile genera in the arid Palearctic, Acanthodactylus, contains two sub-Saharan species with unresolved phylogenetic relationship and unknown climatic preferences. We here aim to understand how and when adaptation to arid conditions occurred in Acanthodactylus and when tropical habitats where entered. Using whole mitogenomes from fresh and archival DNA and published sequences we recovered a well-supported Acanthodactylus phylogeny and underpinned the timing of diversification with environmental niche analyses of the sub-Saharan species A. guineensis and A. boueti in comparison to all arid Acanthodactylus. We found that A. guineensis represents an old lineage that splits from a basal node in the Western clade, and A. boueti is a derived lineage and probably not its sister. Their long branches characterize them—and especially A. guineensis—as lineages that may have persisted for a long time without further diversification or have undergone multiple extinctions. Environmental niche models verified the occurrence of A. guineensis and A. boueti in hot humid environments different from the other 42 arid Acanthodactylus species. While A. guineensis probably remained in tropical habitat from periods prior to the Eocene–Oligocene boundary, A. boueti entered tropical environments independently at a later period. Our results provide an important baseline for studying adaptation and the transition from humid to arid environments in Lacertidae.

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The adaptive challenge of extreme conditions shapes evolutionary diversity of plant assemblages at continental scales

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2021132118 ◽

2021 ◽

Vol 118 (37) ◽

pp. e2021132118

Author(s):

Danilo M. Neves ◽

Andrew J. Kerkhoff ◽

Susy Echeverría-Londoño ◽

Cory Merow ◽

Naia Morueta-Holme ◽

...

Keyword(s):

Biological Diversity ◽

Physiological Stress ◽

Arid Environments ◽

Tropical Environments ◽

Diversity Gradients ◽

Wet Tropics ◽

Plant Assemblages ◽

Temperate Mixed Forests ◽

North And South America ◽

North And South

The tropical conservatism hypothesis (TCH) posits that the latitudinal gradient in biological diversity arises because most extant clades of animals and plants originated when tropical environments were more widespread and because the colonization of colder and more seasonal temperate environments is limited by the phylogenetically conserved environmental tolerances of these tropical clades. Recent studies have claimed support of the TCH, indicating that temperate plant diversity stems from a few more recently derived lineages that are nested within tropical clades, with the colonization of the temperate zone being associated with key adaptations to survive colder temperatures and regular freezing. Drought, however, is an additional physiological stress that could shape diversity gradients. Here, we evaluate patterns of evolutionary diversity in plant assemblages spanning the full extent of climatic gradients in North and South America. We find that in both hemispheres, extratropical dry biomes house the lowest evolutionary diversity, while tropical moist forests and many temperate mixed forests harbor the highest. Together, our results support a more nuanced view of the TCH, with environments that are radically different from the ancestral niche of angiosperms having limited, phylogenetically clustered diversity relative to environments that show lower levels of deviation from this niche. Thus, we argue that ongoing expansion of arid environments is likely to entail higher loss of evolutionary diversity not just in the wet tropics but in many extratropical moist regions as well.

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Bulinus species on Madagascar: molecular evolution, genetic markers and compatibility with Schistosoma haematobium

Parasitology ◽

10.1017/s003118200100806x ◽

2001 ◽

Vol 123 (7) ◽

pp. 261-275 ◽

Cited By ~ 22

Author(s):

J. R. STOTHARD ◽

P. BRÉMOND ◽

L. ANDRIAMARO ◽

B. SELLIN ◽

E. SELLIN ◽

...

Keyword(s):

Phylogenetic Analysis ◽

Ribosomal Subunit ◽

Population Genetic Analysis ◽

Basal Node ◽

Pcr Rflp ◽

Dna Sequence Variation ◽

Long Time ◽

Laboratory Infection ◽

Species Groups ◽

Nucleotide Divergence

Of the four species of Bulinus found on Madagascar, three species: B. obtusispira, B. liratus and B. bavayi are endemic while the fourth, B. forskalii, is probably a recent introduction from the African mainland. The evolutionary relationships of these species with Bulinus species from Africa were studied by phylogenetic analysis of DNA sequence variation at two mitochondrial loci: cytochrome oxidase subunit I (COI) and large ribosomal subunit (LSU) or 16S. The observed levels of nucleotide divergence within Bulinus were substantial but may underestimate the true levels as there was evidence of ‘saturation' of transitional substitutions at both loci. A putative secondary structure model for the sequenced segment of the 16S was developed. Subsequent phylogenetic analysis using transversional changes only for both loci, showed that there were contrasting levels of divergence within the four species groups. B. obtusispira was consistently placed within the B. africanus group, appearing ancestral to this group and was closest to the basal node within Bulinus. Together with B. bavayi, the two species appear to have been isolated on Madagascar for a long time, contrasting with both B. liratus and B. forskalii that appear more recent colonisers; however, estimate of exact times of divergence is problematic. A PCR-RFLP assay was developed to enable identification and discrimination of B. obtusispira and B. liratus using discriminatory variation within the COI. To enable population genetic analysis within B. obtusispira, microsatellite markers were developed using an enrichment method and 8 primer pairs are reported. Laboratory infection experiments using Madasgacan S. haematobium from the Mahabo area showed that certain populations of B. obtusispira, B. liratus and B. bavayi were compatible.

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ANALYSIS OF THE BRI AND CHINA’S OFDI IN SUB-SAHARAN AFRICA

The Singapore Economic Review ◽

10.1142/s0217590820500496 ◽

2020 ◽

pp. 1-25

Author(s):

ZHIKAI WANG ◽

YANGYANG LU ◽

SIMIN ZHANG ◽

ENGIDAW SISAY NEGASH

Keyword(s):

Bilateral Trade ◽

Transportation Cost ◽

Global Strategy ◽

Sub Saharan Africa ◽

Chinese Government ◽

World Population ◽

Cross Border ◽

Long Time ◽

Sub Saharan ◽

The Impact

The “Belt and Road Initiative” (BRI) has been launched by the Chinese government in 2013. The aim was to stimulate cross-border economic development in massive geographical areas covering Asia, Oceania, Europe, Africa, and Latin America which accounts for 80% and 40% of the world population and gross domestic product (GDP), respectively. The BRI has devised an extension of the “going global” strategy to reconfigure China’s overseas sector in order to extend its spillovers, and create more development opportunities for participating countries. In practice, cross-border infrastructure was a comprehensive role to reduce transportation cost; however, the BRI was vast by nature that includes financial support, policy cooperation, investment, trade facilitation, and people-to-people exchanges for the humanitarian strategy. Against this backdrop, the overarching objective of this study was to analyze the impact of the BRI and Chinese outward foreign direct investment (OFDI) on the bilateral trade between China and Sub-Saharan Africa countries. The investigation was carried out using a trade gravity model, balanced panel dataset, and multivariate regression estimation strategy for robustness checks covering 16 years. The result showed that Chinese OFDI, home, and host country’s GDP and GDP per capita income variables have a positive and statistically significant impact on the bilateral trade. Moreover, the BRI has explained positively on the bilateral trade; however, it does not have enough evidence to stimulate significantly, and it usually takes a long time for the effects of the BRI investment on trade and OFDI. The study also found that geographical distance and official exchange rates have explained negatively and statistically significant impact on the bilateral trade.

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The potential role of indigenous resources in the economic development of arid environments in Sub‐Saharan Africa: The case of wildlife utilization in Zimbabwe

Society & Natural Resources ◽

10.1080/08941928909380694 ◽

1989 ◽

Vol 2 (1) ◽

pp. 307-318 ◽

Cited By ~ 1

Author(s):

Kay Muir

Keyword(s):

Economic Development ◽

Potential Role ◽

Sub Saharan Africa ◽

Arid Environments ◽

Wildlife Utilization ◽

Sub Saharan

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Role of temperature in determining relative abundance in cave twilight zones by two species of lungless salamander (family Plethodontidae)

Canadian Journal of Zoology ◽

10.1139/cjz-2013-0178 ◽

2014 ◽

Vol 92 (2) ◽

pp. 119-127 ◽

Cited By ~ 15

Author(s):

Carlos D. Camp ◽

Jessica A. Wooten ◽

John B. Jensen ◽

Dale F. Bartek

Keyword(s):

Thermal Environment ◽

Moisture Regime ◽

Thermal Gradients ◽

Environmental Niche ◽

Plethodon Glutinosus ◽

The Family ◽

Abiotic Variables ◽

Environmental Niche Models ◽

Response To Temperature

Lungless salamanders of the family Plethodontidae have historically been considered to be passive conformers to their surrounding thermal environment because there is no evidence that they thermoregulate behaviourally in the field. In contrast, plethodontids readily choose optimal temperatures when placed on experimental thermal gradients. It has been hypothesized that restriction to moist habitats prevents these salamanders from exploiting thermally diverse microhabitats in nature. We tested this hypothesis, as well as the hypothesis that response to temperature differs among plethodontid species, by investigating the thermal ecology of two species (Cave Salamander, Eurycea lucifuga Rafinesque, 1822, and Northern Slimy Salamander, Plethodon glutinosus (Green, 1818)) occupying twilight zones of six caves in northwestern Georgia. We recorded inside and outside temperatures, as well as the number of each species, for each of three seasons (summer, fall, spring) over 13 years. We also tested for differences in thermal preference along experimental gradients in the laboratory. We further generated environmental niche models (ENMs) to investigate the potential role of abiotic variables, including environmental temperature, in determining the geographic range of each species. We found that both species responded to cave temperature in such a way as to suggest that these salamanders thermoregulate behaviourally when given a diversity of thermal options within a relatively constant moisture regime. We also determined that E. lucifuga prefers lower temperatures than P. glutinosus. ENM analysis indicated that, while abiotic variables both strongly influence the ecological niche of both species, the range of E. lucifuga is strongly predicted by them. The geographic distribution of P. glutinosus is apparently heavily influenced by the presence of closely related, contiguous neighbors with similar niche requirements.

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Environmental niche models for riverine desert fishes and their similarity according to phylogeny and functionality

Ecosphere ◽

10.1002/ecs2.1658 ◽

2017 ◽

Vol 8 (1) ◽

pp. e01658

Author(s):

James E. Whitney ◽

Joanna B. Whittier ◽

Craig P. Paukert

Keyword(s):

Environmental Niche ◽

Desert Fishes ◽

Environmental Niche Models ◽

Niche Models

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Demographic history and niche conservatism of tropical rainforest trees separated along an altitudinal gradient of a biogeographic barrier

Australian Journal of Botany ◽

10.1071/bt14103 ◽

2014 ◽

Vol 62 (5) ◽

pp. 438 ◽

Cited By ~ 8

Author(s):

Rohan Mellick ◽

Peter D. Wilson ◽

Maurizio Rossetto

Keyword(s):

Environmental Change ◽

Demographic History ◽

Environmental Drivers ◽

Environmental Niche ◽

Glacial Cycle ◽

Demographic Response ◽

History Of ◽

Environmental Niche Models ◽

Response To Environmental Change ◽

Niche Models

The genetic disjunctions and distributions of long-lived species provide valuable signatures of past demographic response to environmental change. Here we use genetic markers to study two Elaeocarpus species from the Australian Wet Tropics to understand changes in palaeodistribution and demography associated with environmental change on either side of the Black Mountain Corridor (BMC). Contrasting the genetic structure of species with different distributions along altitudinal gradients is important to explore some of the environmental drivers of adaptive evolution. Using coalescent-based molecular and environmental niche models, we investigate the demographic history of two long-lived, altitudinally differentiated species that were previously identified as genetically divergent across the BMC. The origin of the genetic disjunction across the BMC is inferred to have occurred during the last glacial cycle in relation to 13 combined molecular histories of both plastid and nuclear loci. Interestingly, whereas midland populations show a dynamic history of expansion and contraction, the highland populations do not. Molecular history and environmental niche models show the populations north of the BMC have remained relatively stable over time in response to environmental change. Populations south of the BMC have been more dynamic in response to environmental change. These differences are likely to highlight the topographical character and environmental heterogeneity of areas separated by the BMC.

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A Re-evaluation of Queensland?s Wet Tropics based on ?Primitive? Plants

Pacific Conservation Biology ◽

10.1071/pc090080 ◽

2009 ◽

Vol 15 (2) ◽

pp. 80 ◽

Cited By ~ 11

Author(s):

D. J. Metcalfe ◽

A. J. Ford

Keyword(s):

Rain Forest ◽

New Caledonia ◽

Rain Forests ◽

Family Diversity ◽

The Pacific ◽

Australian Continent ◽

Long Time ◽

The Face ◽

Wet Tropics ◽

Tropical Areas

The diversity of angiosperms in primitive families, which occur in the Wet Tropics of Queensland, is frequently cited as evidence of the ancient nature of the Australian rain forests, but appears to be based on flawed taxonomic assumptions. We point out the error of identifying species as being primitive rather than representing families with ancient origins, list the families from near-basal lineages using a current molecular phylogeny, and compare their diversity with other areas of rain forest in Australia, and with other tropical areas in the Pacific. Twenty-eight dicot families below the eudicot clade may be regarded as near-basal; 16 of these are present in rain forest habitat in the Wet Tropics. The diversity of near-basal families, and of the species and endemics within these families, is similar in New Caledonia, and the family diversity similar to Costa Rica. We suggest that these data are consistent with other evidence that rain forest has persisted on the Australian continent for a long time, and that the role of Australian rain forests in harbouring a significant near-basal component has been underestimated. We also suggest that ongoing management might be focussed at conserving the evolutionary history present in the near-basal lineages, especially in the face of changing climatic patterns.

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