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1.
PeerJ ; 12: e17232, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646479

RESUMO

The species richness in the Neotropics has been linked to environmental heterogeneity and a complex geological history. We evaluated which biogeographic processes were associated with the diversification of Monkey tree frogs, an endemic clade from the Neotropics. We tested two competing hypotheses: the diversification of Phyllomedusinae occurred either in a "south-north" or a "north-south" direction in the Neotropics. We also hypothesized that marine introgressions and Andean uplift had a crucial role in promoting their diversification. We used 13 molecular markers in a Bayesian analysis to infer phylogenetic relationships among 57 species of Phyllomedusinae and to estimate their divergence times. We estimated ancestral ranges based on 12 biogeographic units considering the landscape modifications of the Neotropical region. We found that the Phyllomedusinae hypothetical ancestor range was probably widespread throughout South America, from Western Amazon to Southern Atlantic Forest, at 29.5 Mya. The Phyllomedusines' ancestor must have initially diverged through vicariance, generally followed by jump-dispersals and sympatric speciation. Dispersal among areas occurred mostly from Western Amazonia towards Northern Andes and the South American diagonal of dry landscapes, a divergent pattern from both "south-north" and "north-south" diversification hypotheses. Our results revealed a complex diversification process of Monkey tree frogs, occurring simultaneously with the orogeny of Northern Andes and the South American marine introgressions in the last 30 million years.


Assuntos
Anuros , Teorema de Bayes , Filogenia , Animais , Anuros/genética , Anuros/classificação , América do Sul , Filogeografia , Especiação Genética
2.
Am J Bot ; 111(4): e16306, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38557829

RESUMO

Decades of empirical research have revealed how the geological history of our planet shaped plant evolution by establishing well-known patterns (e.g., how mountain uplift resulted in high rates of diversification and replicate radiations in montane plant taxa). This follows a traditional approach where botanical data are interpreted in light of geological events. In this synthesis, I instead describe how by integrating natural history, phylogenetics, and population genetics, botanical research can be applied alongside geology and paleontology to inform our understanding of past geological and climatic processes. This conceptual shift aligns with the goals of the emerging field of geogenomics. In the neotropics, plant geogenomics is a powerful tool for the reciprocal exploration of two long standing questions in biology and geology: how the dynamic landscape of the region came to be and how it shaped the evolution of the richest flora. Current challenges that are specific to analytical approaches for plant geogenomics are discussed. I describe the scale at which various geological questions can be addressed from biological data and what makes some groups of plants excellent model systems for geogenomics research. Although plant geogenomics is discussed with reference to the neotropics, the recommendations given here for approaches to plant geogenomics can and should be expanded to exploring long-standing questions on how the earth evolved with the use of plant DNA.


Assuntos
Plantas , Plantas/genética , Genômica , Evolução Biológica , Filogenia , Botânica , Genoma de Planta , Geologia
3.
Ecology ; : e4308, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629131

RESUMO

The recent availability of open-access repositories of functional traits has revolutionized trait-based approaches in ecology and evolution. Nevertheless, the underrepresentation of tropical regions and lineages remains a pervasive bias in plant functional trait databases, which constrains large-scale assessments of plant ecology, evolution, and biogeography. Here, we present MelastomaTRAITs 1.0, a comprehensive and updatable database of functional traits for the pantropical Melastomataceae, the ninth-largest angiosperm family with 177 genera and more than 5800 species. Melastomataceae encompass species with a wide diversity of growth forms (herbs, shrubs, trees, epiphytes, and woody climbers), habitats (including tropical forests, savannas, grasslands, and wetlands from sea level to montane areas above the treeline), ecological strategies (from pioneer, edge-adapted and invasive species to shade-tolerant understory species), geographic distribution (from microendemic to continental-wide distribution), reproductive, pollination, and seed dispersal systems. MelastomaTRAITs builds on 581 references, such as taxonomic monographs, ecological research, and unpublished data, and includes four whole-plant traits, six leaf traits, 11 flower traits, 18 fruit traits, and 27 seed traits for 2520 species distributed in 144 genera across all 21 tribes. Most data come from the Neotropics where the family is most species-rich. Miconieae (the largest tribe) contains the highest number of trait records (49.6%) and species (41.1%) records. The trait types with the most information in the database were whole-plant traits, flowers, and leaf traits. With the breadth of functional traits recorded, our database helps to fill a gap in information for tropical plants and will significantly improve our capacity for large-scale trait-based syntheses across levels of organization, plant-animal interactions, regeneration ecology, and thereby support conservation and restoration programs. There are no copyright restrictions on the dataset; please cite this data paper when reusing the data.

4.
Zookeys ; 1192: 111-140, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425443

RESUMO

The hyperdiverse geometrid genus Eois Hübner, estimated to encompass more than 1,000 species, is among the most species-rich genera in all of Lepidoptera. While the genus has attracted considerable attention from ecologists and evolutionary biologists in recent decades, limited progress has been made on its alpha taxonomy. This contribution focuses on the Olivacea clade, whose monophyly has been recognized previously through molecular analyses. We attempt to define the clade from a morphological perspective and recognize the following species based on morphology and genomic data: E.olivacea (Felder & Rogenhofer); E.pseudolivacea Doan, sp. nov.; E.auruda (Dognin), stat. rev.; E.beebei (Fletcher, 1952), stat. rev.; E.boliviensis (Dognin), stat. rev.; and E.parumsimii Doan, sp. nov. Descriptions and illustrations of the immature stages of E.pseudolivacea reared from Piper (Piperaceae) in Ecuador are provided.

5.
Heliyon ; 10(6): e27697, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38524611

RESUMO

Fannia pusio, the chicken dung fly species, remains unexplored despite its forensic, sanitary, and veterinary importance in the Nearctic and Neotropical regions. In this study, we obtained the complete mitochondrial genome of Fannia pusio for the first time using next-generation sequencing. We compared it with previously published mitogenomes of the genus from the Palearctic region, and its phylogenetic position was studied based on the concatenated protein-coding genes (PCGs) dataset of Calyptratae flies. The circular mitochondrial genome of F. pusio is 16,176 bp in length, with a high A + T content (78.3%), whose gene synteny, codon usage analysis, and amino acid frequency are similar to previously reported Fannia mitogenomes. All PCGs underwent purifying selection except the nad2 gene. Interspecific K2P distances of PCGs of Fannia yielded an average of 12.4% (8.1%-21.1%). The Fannia genus is monophyletic and closely related to Muscidae based on molecular data. Further taxonomic sampling is required to deep into the phylogenetic relationships of the originally proposed species-groups and subgroups within the genus. These results provide a valuable dataset for studying the mitochondrial genome evolution and a resource for the taxonomy and systematics of Fannia.

6.
PeerJ ; 12: e16772, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525284

RESUMO

Background: Semiaquatic bugs (Hemiptera: Heteroptera: Gerromorpha) are distributed worldwide and play fundamental roles in limnic ecosystems. They are the most successful group of organisms to occupy the air-water interface, are important models to study ecology and evolution, and can be relevant tools in biomonitoring. Veliidae is the second most speciose family of semiaquatic bugs, but its internal classification, including subfamilies and genera, is artificial and based on symplesiomorphies. One of these non-monophyletic entities is Paravelia Breddin, 1898, the largest genus in the subfamily Veliinae. Results: In an effort to better classify the Veliinae, we describe Foveavelia to hold five South American species previously placed in Paravelia. The new genus is characterized by the following combination of features: unusual coarse cuticular punctures throughout the thorax and abdomen; a pair of small, frosty, pubescent areas formed by a very dense layer of short setae on the anterior lobe of the pronotum; fore tibial grasping comb present only in males; middle tibia with a row of elongate dark-brown trichobothria-like setae on the distal third, decreasing in size distally; macropterous specimens with the apical macula of the forewings elongate and constricted at mid-length, reaching the wing apex; and the male proctiger with a pair of anterodorsal projections. Besides the description, a key to the species of Foveavelia is provided, accompanied by illustrations and a species distribution map.


Assuntos
Heterópteros , Animais , Masculino , Ecossistema , Ecologia , Monitoramento Biológico , América do Sul
7.
Mol Phylogenet Evol ; 193: 108026, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38341007

RESUMO

Ricinulei or hooded tick-spiders are a cryptic and ancient group of arachnids. The order consists of around 100 highly endemic extant species restricted to the Afrotropics and the Neotropics along with 22 fossil species. Their antiquity and low vagility make them an excellent group with which to interrogate biogeographic questions. To date, only four molecular analyses have been conducted on the group and they failed to resolve the relationships of the main lineages and even recovering the non-monophyly of the three genera. These studies were limited to a few Sanger loci or phylogenomic analyses with at most seven ingroup samples. To increase phylogenetic resolution in this little-understood and poorly studied group, we present the most comprehensive phylogenomic study of Ricinulei to date leveraging the Arachnida ultra-conserved element probe set. With a data set of 473 loci across 96 ingroup samples, analyses resolved a monophyletic Neotropical clade consisting of four main lineages. Two of them correspond to the current genera Cryptocellus and Pseudocellus while topology testing revealed one lineage to likely be a phylogenetic reconstruction artefact. The fourth lineage, restricted to Northwestern, Andean South America, is consistent with the Cryptocellus magnus group, likely corresponding to the historical genus Heteroricinoides. Since we did not sample the type species for this old genus, we do not formally re-erect Heteroricinoides but our data suggest the need for a thorough morphological re-examination of Neotropical Ricinulei.


Assuntos
Aracnídeos , Aranhas , Animais , Aracnídeos/genética , Filogenia , América do Sul
8.
New Phytol ; 242(2): 700-716, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382573

RESUMO

Orchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of an up-to-date phylogeographic analysis. We present a new Orchidaceae phylogeny based on combined high-throughput and Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, and c. 7% (1921) of the 29 524 accepted species, and use it to infer geographic range evolution, diversity, and speciation patterns by adding curated geographical distributions from the World Checklist of Vascular Plants. The orchids' most recent common ancestor is inferred to have lived in Late Cretaceous Laurasia. The modern range of Apostasioideae, which comprises two genera with 16 species from India to northern Australia, is interpreted as relictual, similar to that of numerous other groups that went extinct at higher latitudes following the global climate cooling during the Oligocene. Despite their ancient origin, modern orchid species diversity mainly originated over the last 5 Ma, with the highest speciation rates in Panama and Costa Rica. These results alter our understanding of the geographic origin of orchids, previously proposed as Australian, and pinpoint Central America as a region of recent, explosive speciation.


Assuntos
Clima , Orchidaceae , Austrália , Filogenia , Filogeografia , Orchidaceae/genética
9.
PhytoKeys ; 238: 33-64, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344433

RESUMO

The genus Magnolia (Magnoliaceae) has a wide and disjunct geographic distribution ranging from Eastern and South Asia to Malaysia, extending across the Neartics and reaching into the Neotropics. Regarding its infrageneric classification, the genus is divided into three subgenera: Yulania, Gynopodium and Magnolia, the latter including the section Talauma in which the native Brazilian taxa are classified. The species of Magnoliasect.Talauma can be recognized by two parallel longitudinal scars on the petiole formed by the shedding of the stipules, in addition to a woody syncarp that breaks into irregular plates at dehiscence. Currently, in Brazil, species recognition is not clear on national platforms that are widely used by the Brazilian botanical community (e.g. Flora do Brasil), with only two native Magnolia species being accepted: M.amazonica and M.ovata. The lack of knowledge about the species and their respective characteristics has resulted in many identification errors in Brazilian herbaria, which contributes to the lack of knowledge about their current conservation status. We conducted a complete taxonomic revision based on extensive fieldwork, a herbarium survey, along with literature study. Based on this, we propose to recognize three previously described species, supporting the acceptance of five native Magnolias occurring in Brazil, namely: M.amazonica, M.brasiliensis, M.irwiniana, M.ovata and M.sellowiana. However, we follow the Flora do Brasil in maintaining M.paranaensis as a synonym of M.ovata. Additionally, we designate a lectotype for M.sellowiana. We present morphological descriptions and the geographic distribution for each species, in addition to an identification key to all of these plus the two introduced ornamental species from Asia and North America, illustrations, photographs, ecological data, updated conservation status and taxonomic notes.

10.
Insects ; 15(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38392544

RESUMO

The demography and behaviour of Teinopodagrion oscillans was studied in a protected area in the Andean region of Colombia. Adult damselflies were individually marked, and using their recapture histories, we estimated survival, longevity, sex ratio, and population size using Cormack-Jolly-Seber models. Other aspects of their behaviour were recorded. Survival, recapture, and lifespan (14.1 ± 0.59 days) were similar for both sexes and all age groups. Mature males were larger, and the distance from the water was similar for all individuals. The most supported model was the time-dependent model for survival and recapture. This suggests that weather variations affect the demography of this population in a significant way. Individuals exhibited high fidelity to their site perch, perching with open wings near water on a variety of perches. Mature males make short flights from the perch to intercept conspecific and interspecific males and to hunt prey. The tandem position was formed on macrophytes, and then the pair flew away. Oviposition lasted for 11.23 min on average, with the females ovipositing by abdomen submersion. Our results offer insights into the demographic characteristics and behaviour of this species, providing crucial information for the short- and long-term, from the demography of one species to the conservation of ecosystems of the Andean region.

11.
Plant Biol (Stuttg) ; 26(2): 181-187, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38168075

RESUMO

Orchids are notable for the variety of rewards produced for their pollinators. Nevertheless, many species are rewardless and pollinated by food-deceptive strategies. This is the case for Cattleya, a Neotropical genus of more than 100 species supposedly pollinated by food-deception. Here, I studied a member of the clade Sophronitis (Cattleya cernua) in forest areas of southeastern Brazil. The study included analyses of floral morphology, light microscopy of secretory tissues, histochemistry of flower resources, and measurements of nectar volume and concentration. Data on pollinators and mechanisms of pollination were collected in the field by means of film records, while breeding systems were studied using experimental treatments applied to cultivated specimens. The flower traits of Cattleya cernua show strong adaptation to avian pollination. Flowers produce 1-7 µl of a moderately concentrated nectar (17-50%). A secretory tissue at the distal portion of the cuniculus is responsible for nectar secretion. Secreted nectar is stored in the nectar chamber. Pollinaria deposition on the apex of bird beaks allows both short- and long-billed birds to pollinate the flowers. Plants from the studied population were fully self-compatible but pollinator-dependent. Pollinator frequency was higher than in food-deceptive Cattleya. As far as is known, this is the first record of nectar production in Cattleya. The discovery of a reward-producing species (C. cernua) within a genus entirely pollinated by food-deception strategies (Cattleya) provides clues and new insights into understanding the diversification of Laeliinae across the Neotropics.


Assuntos
Orchidaceae , Néctar de Plantas , Animais , Polinização , Melhoramento Vegetal , Flores/anatomia & histologia , Aves
12.
Zookeys ; 1188: 47-90, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38222295

RESUMO

In this paper, 15 new species of microcaddisflies in the genus Neotrichia Morton, 1905 (Trichoptera, Hydroptilidae) from Panama are described and illustrated: Neotrichiaabrebotellasp. nov.; Neotrichiacandelasp. nov.; Neotrichiacodazasp. nov.; Neotrichiaemberasp. nov.; Neotrichiaflennikenisp. nov.; Neotrichiahondasp. nov.; Neotrichialandisaesp. nov.; Neotrichialenatisp. nov.; Neotrichiamindyaesp. nov.; Neotrichiapanamensissp. nov.; Neotrichiaparajarochitasp. nov.; Neotrichiaparaxicanasp. nov.; Neotrichiasnixaesp. nov.; Neotrichiaspanglerisp. nov.; Neotrichiaveraguasensissp. nov. In addition, two new country records are presented: Neotrichiaminutisimella (Chambers, 1873) and Neotrichiavibrans Ross, 1944. Finally, the male of N.vibrans is re-illustrated, the female is illustrated and descriptive information given, and a key is provided to the males of all current Neotrichia species in Panama. There are now 45 species of Neotrichia and a total of 525 Trichoptera species recorded from Panama.

13.
Plants (Basel) ; 13(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38256775

RESUMO

Prosthechea jauana has been recognized as an orchid species endemic to the Venezuelan tepui. The first record of P. jauana in Brazil is presented here, also from a tepui in the Southern phytogeographical district of Pantepui in the Serra do Aracá, at the northern border of the Amazonas state. A detailed morphological description and images of the specimen are presented, as well as an updated distribution map, preliminary conservation status assessment, and taxonomic notes about the species. In addition, we provide species' distribution models for P. jauana based on current and future bioclimatic data. Future projections suggest that the geographic distribution of P. jauana will likely be severely affected, with ~79% of its suitable habitat being reduced by 2041-2060 and ~92% by 2061-2080. Prosthechea jauana could represent a flag species and an example of how climate change may affect the endemic Pantepui flora.

14.
Mol Phylogenet Evol ; 192: 108008, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38181828

RESUMO

Two main landscapes emerge from the Guiana Shield: the highlands to the west called the Pantepui region and the Amazonian lowlands to the east, both harbouring numerous endemic species. With 32 currently recognized species, the genus Anomaloglossus stands out among Neotropical frogs as one that diversified only within the Guiana Shield both in the highlands and the lowlands. We present a time-calibrated phylogeny obtained by using combined mitogenomic and nuclear DNA, which suggests that the genus originates from Pantepui where extant lineages started diversifying around 21 Ma, and subsequently (ca. 17 Ma) dispersed during the Miocene Climatic Optimum to the lowlands of the eastern Guiana Shield where the ability to produce endotrophic tadpoles evolved. Further diversification within the lowlands in the A. stepheni group notably led to an evolutionary reversal toward exotrophy in one species group during the late Miocene, followed by reacquisition of endotrophy during the Pleistocene. These successive shifts of reproductive mode seem to have accompanied climatic oscillations. Long dry periods might have triggered evolution of exotrophy, whereas wetter climates favoured endotrophic forms, enabling colonization of terrestrial habitats distant from water. Acquisition, loss, and reacquisition of endotrophy makes Anomaloglossus unique among frogs and may largely explain the current species diversity. The micro evolutionary processes involved in these rapid shifts of reproductive mode remain to be revealed.


Assuntos
Anuros , Ecossistema , Animais , Anuros/genética , Filogenia , Filogeografia
15.
Mol Phylogenet Evol ; 191: 107971, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38000706

RESUMO

The iconic mountains of the Pantepui biogeographical region host many early-diverging endemic animal and plant lineages, concurring with Conan Doyle's novel about an ancient "Lost World". While this is the case of several frog lineages, others appear to have more recent origins, adding to the controversy around the diversification processes in this region. Due to its remoteness, Pantepui is challenging for biological surveys, and only a glimpse of its biodiversity has been described, which hampers comprehensive evolutionary studies in many groups. During a recent expedition to the Neblina massif on the Brazil-Venezuela border, we sampled two new frog species that could not be assigned to any known genus. Here, we perform phylogenetic analyses of mitogenomic and nuclear loci to infer the evolutionary relationships of the new taxa and support their description. We find that both species represent single lineages deeply nested within Brachycephaloidea, a major Neotropical clade of direct-developing frogs. Both species diverged >45 Ma from their closest relatives: the first is sister to all other Brachycephaloidea except for Ceuthomantis, another Pantepui endemic, and the second is sister to Brachycephalidae, endemic to the Brazilian Atlantic Forest. In addition to these considerable phylogenetic and biogeographic divergences, external morphology and osteological features support the proposition of two new family and genus-level taxa to accommodate these new branches of the amphibian tree of life. These findings add to other recently described ancient vertebrate lineages from the Neblina massif, providing a bewildering reminder that our perception of the Pantepui's biodiversity remains vastly incomplete. It also provides insights into how these mountains acted as "museums" during the diversification of Brachycephaloidea and of Neotropical biotas more broadly, in line with the influential "Plateau theory". Finally, these discoveries point at the yet unknown branches of the tree of life that may go extinct, due to global climate change and zoonotic diseases, before we even learn about their existence, amphibians living at higher elevations being particularly at risk.


Assuntos
Anuros , Museus , Animais , Filogenia , Anuros/genética , Biodiversidade , Evolução Biológica
16.
Mol Phylogenet Evol ; 190: 107970, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37995894

RESUMO

Armored catfishes of the genus Eurycheilichthys are endemic to Southern Brazil and Misiones (Argentina) comprising nine species of small size, with a high degree of sympatry and species diversity distributed in two river basins. Here we use new genome-wide data to infer a species phylogeny and test species boundaries for this poorly known group. We estimate 1) the phylogenetic relationships of the species of Eurycheilichthys based on 29,350 loci in 65 individuals of nine species plus outgroups, and 2) the population structure and differentiation based on 43,712 loci and 62 individuals to estimate how geography may have acted on speciation and formation of the sympatric species groups. Analyses support the monophyly of the genus and suggest two species-inclusive clades (East and West) with high support and very recently diverged species. Western clade contains E. limulus (from upper Jacuí River basin) that is sister to Western species of the Taquari-Antas basin plus E. paucidens. The Eastern clade contains E. pantherinus (from Uruguay River basin) sister to the Eastern species of the Taquari-Antas basin E. coryphaenus, plus the central-distributed species E. planus and E. vacariensis, and the more widely-distributed species E. luisae. Eurycheilichthys luisae is not monophyletic and may contain one or more cryptic species or hybrid individuals. A stronger diversity on structure of lineages on the Taquari-Antas, when compared to upper Uruguay and Jacuí River basins, and the fact that most of the sympatrically distributed taxa have non-sister relationships suggest a scenario of mainly allopatric speciation and may indicate a more dynamic landscape with headwater capture events among these tributaries.


Assuntos
Peixes-Gato , Simpatria , Humanos , Animais , Filogenia , Peixes-Gato/genética , Geografia , Brasil
17.
Mol Phylogenet Evol ; 190: 107965, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37977500

RESUMO

Poeciliids (Cyprinodontiformes: Poeciliidae), commonly known as livebearers, are popular fishes in the aquarium trade (e.g., guppies, mollies, swordtails) that are widely distributed in the Americas, with 274 valid species in 27 genera. This group has undergone various taxonomic changes recently, spurred by investigations using traditional genetic markers. Here we used over 1,000 ultraconserved loci to infer the relationships within Poeciliidae in the first attempt at understanding their diversification based on genome-scale data. We explore gene tree discordance and investigate potential incongruence between concatenation and coalescent inference methods. Our aim is to examine the influence of incomplete lineage sorting and reticulate evolution on the poeciliids' evolutionary history and how these factors contribute to the observed gene tree discordace. Our concatenated and coalescent phylogenomic inferences recovered four major clades within Poeciliidae. Most supra-generic level relationships we inferred were congruent with previous molecular studies, but we found some disagreements; the Middle American taxa Phallichthys and Poecilia (Mollienesia) were recovered as non-monophyletic, and unlike other recent molecular studies, we recovered Brachyrhaphis as monophyletic. Our study is the first to provide signatures of reticulate evolution in Poeciliidae at the family level; however, continued finer-scale investigations are needed to understand the complex evolutionary history of the family along with a much-needed taxonomic re-evaluation.


Assuntos
Ciprinodontiformes , Poecilia , Animais , Filogenia , Ciprinodontiformes/genética , Poecilia/genética , Genoma , Marcadores Genéticos
18.
Ecology ; 105(2): e4206, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37950619

RESUMO

The climate variability hypothesis posits that an organism's exposure to temperature variability determines the breadth of its thermal tolerance and has become an important framework for understanding variation in species' susceptibilities to climate change. For example, ectotherms from more thermally stable environments tend to have narrower thermal tolerances and greater sensitivity to projected climate warming. Among endotherms, however, the relationship between climate variability and thermal physiology is less clear, particularly with regard to microclimate variation-small-scale differences within or between habitats. To address this gap, we explored associations between two sources of temperature variation (habitat type and vertical forest stratum) and (1) thermal physiological traits and (2) temperature sensitivity metrics within a diverse assemblage of Neotropical birds (n = 89 species). We used long-term temperature data to establish that daily temperature regimes in open habitats and forest canopy were both hotter and more variable than those in the forest interior and forest understory, respectively. Despite these differences in temperature regime, however, we found little evidence that species' thermal physiological traits or temperature sensitivity varied in association with either habitat type or vertical stratum. Our findings provide two novel and important insights. First, and in contrast to the supporting empirical evidence from ectotherms, the thermal physiology of birds at our study site appears to be largely decoupled from local temperature variation, providing equivocal support for the climate variability hypothesis in endotherms. Second, we found no evidence that the thermal physiology of understory forest birds differed from that of canopy or open-habitat species-an oft-invoked, yet previously untested, mechanism for why these species are so vulnerable to environmental change.


Assuntos
Ecossistema , Florestas , Animais , Temperatura , Mudança Climática , Aves
19.
Mol Phylogenet Evol ; 190: 107960, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918683

RESUMO

The cycad genus Ceratozamia comprises 40 species from Mexico, Guatemala, Belize, and Honduras, where cycads occur throughout climatically varied montane habitats. Ceratozamia has the potential to reveal the history and processes of species diversification across diverse Neotropical habitats in this region. However, the species relationships within Ceratozamia and the ecological trends during its evolution remain unclear. Here, we aimed to clarify the phylogenetic relationships, the timing of clade and species divergences, and the niche evolution throughout the phylogenetic history of Ceratozamia. Genome-wide DNA sequences were obtained with MIG-seq, and multiple data-filtering steps were used to optimize the dataset used to construct an ultrametric species tree. Divergence times among branches and ancestral niches were estimated. The niche variation among species was evaluated, summarized into two principal components, and their ancestral states were reconstructed to test whether niche shifts among branches can be explained by random processes, under a Brownian Motion model. Ceratozamia comprises three main clades, and most species relationships within the clades were resolved. Ceratozamia has diversified since the Oligocene, with major branching events occurring during the Miocene. This timing is consistent with fossil evidence, the timing estimated for other Neotropical plant groups, and the major geological events that shaped the topographic and climatic variation in Mexico. Patterns of niche evolution in the genus do not accord with the Brownian Motion model. Rather, non-random evolution with shifts towards more seasonal environments at high latitudes, or shifts towards humid or dry environments at low latitudes explain the diversification of Ceratozamia. We present a comprehensive phylogenetic reconstruction for Ceratozamia and identify for the first time the environmental factors involved in clade and species diversification within the genus. This study alleviates the controversies regarding the species relationships in the genus and provides the first evidence that latitude-associated environmental factors may influence processes of niche evolution in cycads.


Assuntos
Zamiaceae , Filogenia , Zamiaceae/genética , Filogeografia , Ecossistema , Fatores de Tempo
20.
Acta Trop ; 249: 107051, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37875169

RESUMO

In the Yucatan Peninsula, tropical preserved forests harbor a high diversity of phlebotomine sand fly species, potential vectors of Leishmania. As a result, a significant risk of contracting localized cutaneous leishmaniasis (LCL) is associated with entry into these forest ecosystems. However, with the current trajectory of land use in the region, communities now live within modified landscapes which could increase their risk of contact with vectors. In this study, we characterized the sand fly fauna and its relationship with the characteristics of peridomestic habitats in two rural communities in Yucatan characterized by contrasting records of leishmaniasis. Five human dwellings in each community were randomly selected and the peridomestic landscape was characterized (i.e., type and percentage of land use). For the collection of sand flies, CDC traps were deployed in both the intra and peridomicile. Differences in alpha and beta diversity between communities and ecotopes were estimated considering three separate groups, all species together, zoophilic species, and anthropophilic species. In total, 1, 241 sand flies represented by eight species were collected from November 2021-March 2022. Both communities registered the presence of sand flies in the intra and peridomicile, and females were more abundant than males. However, the greatest diversity of species was recorded in the peridomicile of the community with the highest composition of land uses. Our study demonstrates that the transformation of the forest around the communities favors the abundance and richness of sand flies in the peridomestic environment. We discuss the limitations and implications of our findings regarding the potential risk of the emergence of peri­rural cycles of leishmaniasis in the region.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Psychodidae , Humanos , Masculino , Animais , Feminino , Ecossistema , México/epidemiologia , População Rural , Insetos Vetores , Leishmaniose Cutânea/epidemiologia
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