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1.
Syst Parasitol ; 101(4): 44, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38839661

RESUMEN

Species of Diolcogaster parasitize Lepidoptera pests of commercial plants. The diversity of this genus is high, but few species of Diolcogaster have been described. The description of a new Diolcogaster species provides information for the biological control using this insect. This study presents the description and key notes on the biology of a new Diolcogaster parasitoid wasp. This species was reared from a caterpillar of Hypercompe brasiliensis collected after feeding on a Gloxinia perennis plant important to floriculture. Two complementary identification analyzes were performed on Diolcogaster adult bodies. The first was the analyses of its external morphology and the second its molecular analysis (mitochondrial DNA). The morphological analysis defined the insect as a new species of Diolcogaster, named Diolcogaster joanesi sp. nov. A maximum-likelihood (ML) analysis partially confirmed the morphological analysis, placing D. joanesi within a cluster including a previously identified species (Diolcogaster choi) and seven other morphospecies. The proximity of D. joanesi to D. choi is discussed and an updated key for all New World species of the xanthaspis group is provided. Twenty-eight adult wasps were obtained (22 females and six males) out of 50 cocoons which larvae emerged from the caterpillar host. The findings contribute to the broader understanding of Diolcogaster in the Neotropics and its potential for the biological control of lepidopteran defoliators.


Asunto(s)
Control Biológico de Vectores , Especificidad de la Especie , Avispas , Animales , Brasil , Avispas/clasificación , Avispas/anatomía & histología , Mariposas Nocturnas/parasitología , Lepidópteros/parasitología , Filogenia , Larva , Femenino
2.
Anat Histol Embryol ; 53(4): e13064, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38841825

RESUMEN

There are different strains of laboratory mouse used in many different fields. These strains differ anatomically. In order to determine these anatomical differences, shape analysis was conducted according to species. CD-1, C57bl/6 and Balb-c strains were preferred to study these differences. Forty-eight adult mouse strains belonging to these strains were utilized. The bones were photographed and geometric morphometry was applied to these photographs. Principal Component Analysis was applied to determine shape variations. In Principal component 1 for cranium, CD-1 and C57bl/6 strain groups showed different shape variations, while Balb-c strain group showed similar shape variations to the other strain groups. Principal Component 1 for the mandible separated the CD-1 and C57bl/6 strain groups in terms of shape variation. Principal Component 2 explained most of the variation between the C57bl/6 and CD-1 lineage groups. In PC1 for molars, the CD-1 group showed a different shape variation from the other groups. Mahalanobis distances and Procrustes distances were measured using Canonical variance analysis to explain the differences between the lineage groups. These measurements were statistically significant. For cranium, in canonical variate 1, CD-1 group of mouse and Balb-c group of mouse were separated from each other. In canonical variate 2, C57bl/6 group of mouse were separated from the other groups. For mandible, Balb-c group of mouse in canonical variate 1 and CD-1 group of mouse in canonical variate 2 were separated from the other groups. For molars, CD-1 group of mouse in canonical variate 1 and Balb-c group of mouse in canonical variate 2 were separated from the other groups. It was thought that these anatomical differences could be caused by genotypic factors as well as dietary differences and many different habits that would affect the way their muscles work.


Asunto(s)
Mandíbula , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Cráneo , Animales , Cráneo/anatomía & histología , Ratones/anatomía & histología , Mandíbula/anatomía & histología , Ratones Endogámicos BALB C/anatomía & histología , Ratones Endogámicos C57BL/anatomía & histología , Diente/anatomía & histología , Análisis de Componente Principal , Especificidad de la Especie , Masculino
3.
PLoS One ; 19(6): e0304799, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38833482

RESUMEN

The adaptative responses and divergent evolution shown in the environments habited by the Cichlidae family allow to understand different biological properties, including fish genetic diversity and structure studies. In a zone that has been historically submitted to different anthropogenic pressures, this study assessed the genetic diversity and population structure of cichlid Caquetaia kraussii, a sedentary species with parental care that has a significant ecological role for its contribution to redistribution and maintenance of sedimentologic processes in its distribution area. This study developed de novo 16 highly polymorphic species-specific microsatellite loci that allowed the estimation of the genetic diversity and differentiation in 319 individuals from natural populations in the area influenced by the Ituango hydroelectric project in the Colombian Cauca River. Caquetaia kraussii exhibits high genetic diversity levels (Ho: 0.562-0.885; He: 0.583-0.884) in relation to the average neotropical cichlids and a three group-spatial structure: two natural groups upstream and downstream the Nechí River mouth, and one group of individuals with high relatedness degree, possibly independently formed by founder effect in the dam zone. The three genetic groups show recent bottlenecks, but only the two natural groups have effective population size that suggest their long-term permanence. The information generated is relevant not only for management programs and species conservation purposes, but also for broadening the available knowledge on the factors influencing neotropical cichlids population genetics.


Asunto(s)
Cíclidos , Variación Genética , Genética de Población , Repeticiones de Microsatélite , Ríos , Repeticiones de Microsatélite/genética , Animales , Colombia , Cíclidos/genética , Especificidad de la Especie
4.
PLoS One ; 19(6): e0300664, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38829847

RESUMEN

Acoustic surveys of bat echolocation calls are an important management tool for determining presence and probable absence of threatened and endangered bat species. In the northeastern United States, software programs such as Bat Call Identification (BCID), Kaleidoscope Pro (KPro), and Sonobat can automatically classify ultrasonic detector sound files, yet the programs' accuracy in correctly classifying calls to species has not been independently assessed. We used 1,500 full-spectrum reference calls with known identities for nine northeastern United States bat species to test the accuracy of these programs using calculations of Positive Predictive Value (PPV), Negative Predictive Value (NPV), Sensitivity (SN), Specificity (SP), Overall Accuracy, and No Information Rate. We found that BCID performed less accurately than other programs, likely because it only operates on zero-crossing data and may be less accurate for recordings converted from full-spectrum to zero-crossing. NPV and SP values were high across all species categories for SonoBat and KPro, indicating these programs' success at avoiding false positives. However, PPV and SN values were relatively low, particularly for individual Myotis species, indicating these programs are prone to false negatives. SonoBat and KPro performed better when distinguishing Myotis species from non-Myotis species. We expect less accuracy from these programs for acoustic recordings collected under normal working conditions, and caution that a bat acoustic expert should verify automatically classified files when making species-specific regulatory or conservation decisions.


Asunto(s)
Quirópteros , Ecolocación , Quirópteros/fisiología , Quirópteros/clasificación , Animales , Ecolocación/fisiología , New England , Vocalización Animal/fisiología , Programas Informáticos , Especificidad de la Especie , Acústica
5.
Nat Commun ; 15(1): 4725, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38830879

RESUMEN

Non-genetic sources of phenotypic variation, such as the epigenome and the microbiome, could be important contributors to adaptive variation for species with low genetic diversity. However, little is known about the complex interaction between these factors and the genetic diversity of the host, particularly in wild populations. Here, we examine the skin microbiome composition of two closely-related mangrove killifish species with different mating systems (self-fertilising and outcrossing) under sympatric and allopatric conditions. This allows us to partition the influence of the genotype and the environment on their microbiome and (previously described) epigenetic profiles. We find the diversity and community composition of the skin microbiome are strongly shaped by the environment and, to a lesser extent, by species-specific influences. Heterozygosity and microbiome alpha diversity, but not epigenetic variation, are associated with the fluctuating asymmetry of traits related to performance (vision) and behaviour (aggression). Our study identifies that a proportion of the epigenetic diversity and microbiome differentiation is unrelated to genetic variation, and we find evidence for an associative relationship between microbiome and epigenetic diversity in these wild populations. This suggests that both mechanisms could potentially contribute to variation in species with low genetic diversity.


Asunto(s)
Epigénesis Genética , Variación Genética , Microbiota , Animales , Microbiota/genética , Piel/microbiología , Ciprinodontiformes/genética , Ciprinodontiformes/microbiología , Masculino , Genotipo , Especificidad de la Especie , Femenino
6.
Brief Bioinform ; 25(4)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38856169

RESUMEN

Transcriptomic analysis across species is increasingly used to reveal conserved gene regulations which implicate crucial regulators. Cross-species analysis of single-cell RNA sequencing (scRNA-seq) data provides new opportunities to identify the cellular and molecular conservations, especially for cell types and cell type-specific gene regulations. However, few methods have been developed to analyze cross-species scRNA-seq data to uncover both molecular and cellular conservations. Here, we built a tool called CACIMAR, which can perform cross-species analysis of cell identities, markers, regulations, and interactions using scRNA-seq profiles. Based on the weighted sum models of the conserved features, we developed different conservation scores to measure the conservation of cell types, regulatory networks, and intercellular interactions. Using publicly available scRNA-seq data on retinal regeneration in mice, zebrafish, and chick, we demonstrated four main functions of CACIMAR. First, CACIMAR allows to identify conserved cell types even in evolutionarily distant species. Second, the tool facilitates the identification of evolutionarily conserved or species-specific marker genes. Third, CACIMAR enables the identification of conserved intracellular regulations, including cell type-specific regulatory subnetworks and regulators. Lastly, CACIMAR provides a unique feature for identifying conserved intercellular interactions. Overall, CACIMAR facilitates the identification of evolutionarily conserved cell types, marker genes, intracellular regulations, and intercellular interactions, providing insights into the cellular and molecular mechanisms of species evolution.


Asunto(s)
Análisis de Secuencia de ARN , Análisis de la Célula Individual , Pez Cebra , Animales , Análisis de la Célula Individual/métodos , Ratones , Pez Cebra/genética , Análisis de Secuencia de ARN/métodos , Especificidad de la Especie , Programas Informáticos , Redes Reguladoras de Genes , Perfilación de la Expresión Génica/métodos , Pollos , Biomarcadores/metabolismo , Biología Computacional/métodos , Regulación de la Expresión Génica
7.
PeerJ ; 12: e17406, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38860213

RESUMEN

Amphibians are experiencing declines globally, with emerging infectious diseases as one of the main causes. Haematological parameters present a useful method for determining the health status of animals and the effects of particular diseases, but the interpretation of differential cell counts relies on knowing the normal ranges for the species and factors that can affect these counts. However, there is very little data on either normal haematological parameters or guides for blood cell types for free-ranging frog species across the world. This study aims to 1) create a visual guide for three different Australian frog species: Litoria paraewingi, Limnodynastes dumerilii, and Crinia signifera, 2) determine the proportions of erythrocytes to leukocytes and 3) differential leukocytes within blood smears from these three species and 4) assess the association between parasites and differential counts. We collected blood samples from free-ranging frogs and analysed blood smears. We also looked for ectoparasites and tested for the fungal disease chytridiomycosis. Overall, we found that the differentials of erythrocytes to leukocytes were not affected by species, but the proportions of different leukocytes did vary across species. For example, while lymphocytes were the most common type of leukocyte across the three species, eosinophils were relatively common in Limnodynastes dumerilii but rarely present in the other two species. We noted chytridiomycosis infection as well as ectoparasites present in some individuals but found no effect of parasites on blood parameters. Our results add baseline haematological parameters for three Australian frog species and provide an example of how different frog species can vary in their differential blood cell counts. More information is needed on frog haematological data before these parameters can be used to determine the health status of wild or captive frogs.


Asunto(s)
Anuros , Animales , Anuros/sangre , Anuros/parasitología , Anuros/microbiología , Australia , Valores de Referencia , Eritrocitos/parasitología , Recuento de Células Sanguíneas/veterinaria , Pruebas Hematológicas/veterinaria , Especificidad de la Especie , Recuento de Leucocitos , Masculino
8.
PeerJ ; 12: e17278, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38827282

RESUMEN

In this article, the history and taxonomy of Placoneis gastrum, the type species of the genus Placoneis, was discussed. We investigated the structure of pore occlusions in Placoneis and related genera. As a result, we propose a new classification for tectulum-like types of pore occlusions. The new classification is congruent with previously-published and newly-constructed phylogenies based on molecular data. Based on the different structures of the pore occlusions, species of Placoneis are transferred to Witkowskia gen. nov. Hence, 168 new combinations are introduced. A new diatom species, with a similar morphology to Placoneis flabellata, was discovered in Bac Kan Province, Vietnam. It is described in this article as Chudaevia densistriata sp. nov. Placoneis flabellata is transferred to Chudaevia gen. nov. We also illustrate Placoneis flabellata herein and compare it to Chudaevia densistriata sp. nov. An unknown diatom, similar to Placoneis coloradensis, was discovered in Chukotka, Russia. It is introduced as Placoneis elinae sp. nov. below. Additionally, we discuss the distribution of some species of Witkowskia gen. nov. and Chudaevia gen. nov.


Asunto(s)
Diatomeas , Filogenia , Diatomeas/clasificación , Vietnam , Federación de Rusia , Especificidad de la Especie
9.
J Comp Psychol ; 138(2): 77-79, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38829346

RESUMEN

Comments on an article by Jay W. Schwartz , Kayleigh H. Pierson, and Alexander K. Reece (see record 2024-19488-001). In this issue, Schwartz et al. (2024) tackle the pitch rule in humans by testing to what extent we use pitch alone to judge emotional arousal across closely and distantly related animal species. The findings of Schwartz et al. open a number of intriguing possibilities for future research: Notably important additional steps would include to further investigate the accuracy of the pitch rule across closely and distantly related species. Upon this, in order to study the evolutionary ancestry of the pitch rule, it will be necessary to study its applicability across nonhumans. Particularly interesting would be the inclusion of subject species that have been found to eavesdrop on heterospecific alarm calls. Previous research (see Hoeschele, 2017 for a review) as well as present findings on human ratings of macaque versus cricket calls also suggest that we should additionally focus on sound features that compliment emotional arousal rating beyond pitch such as spectral information. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Nivel de Alerta , Emociones , Humanos , Nivel de Alerta/fisiología , Emociones/fisiología , Animales , Percepción de la Altura Tonal/fisiología , Especificidad de la Especie
10.
Sci Adv ; 10(23): eadm7273, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38848365

RESUMEN

By analyzing 15,000 samples from 348 mammalian species, we derive DNA methylation (DNAm) predictors of maximum life span (R = 0.89), gestation time (R = 0.96), and age at sexual maturity (R = 0.85). Our maximum life-span predictor indicates a potential innate longevity advantage for females over males in 17 mammalian species including humans. The DNAm maximum life-span predictions are not affected by caloric restriction or partial reprogramming. Genetic disruptions in the somatotropic axis such as growth hormone receptors have an impact on DNAm maximum life span only in select tissues. Cancer mortality rates show no correlation with our epigenetic estimates of life-history traits. The DNAm maximum life-span predictor does not detect variation in life span between individuals of the same species, such as between the breeds of dogs. Maximum life span is determined in part by an epigenetic signature that is an intrinsic species property and is distinct from the signatures that relate to individual mortality risk.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Longevidad , Mamíferos , Animales , Longevidad/genética , Mamíferos/genética , Femenino , Humanos , Masculino , Rasgos de la Historia de Vida , Especificidad de la Especie
11.
Proc Biol Sci ; 291(2024): 20232811, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38864325

RESUMEN

Pesticides have been identified as major drivers of insect biodiversity loss. Thus, the study of their effects on non-pest insect species has attracted a lot of attention in recent decades. In general toxicology, the 'gold standard' to assess the toxicity of a substance is to measure mass-specific LD50 (i.e. median lethal dose per unit body mass). In entomology, reviews attempting to compare these data across all available studies are lacking. To fill this gap in knowledge, we performed a systematic review of the lethality of imidacloprid for adult insects. Imidacloprid is possibly the most extensively studied insecticide in recent times, yet we found that little is comparable across studies, owing to both methodological divergence and missing estimates of body mass. By accounting for body mass whenever possible, we show how imidacloprid sensitivity spans across an apparent range of approximately six orders of magnitude across insect species. Very high variability within species can also be observed owing to differences in exposure methods and observation time. We suggest that a more comparable and comprehensive approach has both biological and economic relevance. Ultimately, this would help to identify differences that could direct research towards preventing non-target species from being negatively affected.


Asunto(s)
Imidazoles , Insectos , Insecticidas , Neonicotinoides , Nitrocompuestos , Especificidad de la Especie , Neonicotinoides/toxicidad , Nitrocompuestos/toxicidad , Animales , Insecticidas/toxicidad , Insectos/efectos de los fármacos , Imidazoles/toxicidad , Dosificación Letal Mediana
12.
Invertebr Syst ; 382024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38838190

RESUMEN

Hymenoptera has some of the highest diversity and number of individuals among insects. Many of these species potentially play key roles as food sources, pest controllers and pollinators. However, little is known about the diversity and biology and ~80% of the species have not yet been described. Classical taxonomy based on morphology is a rather slow process but DNA barcoding has already brought considerable progress in identification. Innovative methods such as image-based identification and automation can further speed up the process. We present a proof of concept for image data recognition of a parasitic wasp family, the Diapriidae (Hymenoptera), obtained as part of the GBOL III project. These tiny (1.2-4.5mm) wasps were photographed and identified using DNA barcoding to provide a solid ground truth for training a neural network. Taxonomic identification was used down to the genus level. Subsequently, three different neural network architectures were trained, evaluated and optimised. As a result, 11 different genera of diaprids and one mixed group of 'other Hymenoptera' can be classified with an average accuracy of 96%. Additionally, the sex of the specimen can be classified automatically with an accuracy of >97%.


Asunto(s)
Redes Neurales de la Computación , Avispas , Animales , Avispas/genética , Avispas/anatomía & histología , Código de Barras del ADN Taxonómico , Procesamiento de Imagen Asistido por Computador/métodos , Femenino , Clasificación/métodos , Especificidad de la Especie , Masculino
13.
Syst Parasitol ; 101(4): 45, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38877199

RESUMEN

Platybothrium Linton, 1890 is a genus parasitizing sharks of the families Carcharhinidae and Sphyrnidae. No new species has been assigned to the genus in the 20 years since its last treatment. In the present study, a new species is described from the Persian Gulf, which is the second report of a species of Platybothrium in the Indian Ocean. Platybothrium yanae sp. nov. differs from P. auriculatum Yamaguti, 1952, P. cervinum Linton, 1890, P. tantulum Healy, 2003, and P. kirstenae Healy, 2003 in lacking, rather than having, an accessory piece between its hooks. This new species is distinguished from its other congeners by having a particular combination of features including its measurements, morphology, and meristic features, bringing the number of valid species in the genus to 11.


Asunto(s)
Cestodos , Tiburones , Especificidad de la Especie , Animales , Tiburones/parasitología , Cestodos/clasificación , Cestodos/anatomía & histología , Irán , Océano Índico
14.
Nat Commun ; 15(1): 5091, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38876988

RESUMEN

Living organisms synchronize their biological activities with the earth's rotation through the circadian clock, a molecular mechanism that regulates biology and behavior daily. This synchronization factually maximizes positive activities (e.g., social interactions, feeding) during safe periods, and minimizes exposure to dangers (e.g., predation, darkness) typically at night. Beyond basic circadian regulation, some behaviors like sleep have an additional layer of homeostatic control, ensuring those essential activities are fulfilled. While sleep is predominantly governed by the circadian clock, a secondary homeostatic regulator, though not well-understood, ensures adherence to necessary sleep amounts and hints at a fundamental biological function of sleep beyond simple energy conservation and safety. Here we explore sleep regulation across seven Drosophila species with diverse ecological niches, revealing that while circadian-driven sleep aspects are consistent, homeostatic regulation varies significantly. The findings suggest that in Drosophilids, sleep evolved primarily for circadian purposes. The more complex, homeostatically regulated functions of sleep appear to have evolved independently in a species-specific manner, and are not universally conserved. This laboratory model may reproduce and recapitulate primordial sleep evolution.


Asunto(s)
Evolución Biológica , Ritmo Circadiano , Drosophila , Sueño , Especificidad de la Especie , Animales , Sueño/fisiología , Drosophila/fisiología , Ritmo Circadiano/fisiología , Homeostasis , Relojes Circadianos/fisiología , Masculino , Femenino
15.
Sci Rep ; 14(1): 13760, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877021

RESUMEN

Elevated atmospheric carbon dioxide (eCO2) can affect plant growth and physiology, which can, in turn, impact herbivorous insects, including by altering pollen or plant tissue nutrition. Previous research suggests that eCO2 can reduce pollen nutrition in some species, but it is unknown whether this effect is consistent across flowering plant species. We experimentally quantified the effects of eCO2 across multiple flowering plant species on plant growth in 9 species and pollen chemistry (%N an estimate for protein content and nutrition in 12 species; secondary chemistry in 5 species) in greenhouses. For pollen nutrition, only buckwheat significantly responded to eCO2, with %N increasing in eCO2; CO2 treatment did not affect pollen amino acid composition but altered secondary metabolites in buckwheat and sunflower. Plant growth under eCO2 exhibited two trends across species: plant height was taller in 44% of species and flower number was affected for 63% of species (3 species with fewer and 2 species with more flowers). The remaining growth metrics (leaf number, above-ground biomass, flower size, and flowering initiation) showed divergent, species-specific responses, if any. Our results indicate that future eCO2 is unlikely to uniformly change pollen chemistry or plant growth across flowering species but may have the potential to alter ecological interactions, or have particularly important effects on specialized pollinators.


Asunto(s)
Dióxido de Carbono , Polen , Dióxido de Carbono/metabolismo , Polen/crecimiento & desarrollo , Polen/metabolismo , Atmósfera/química , Especificidad de la Especie , Magnoliopsida/crecimiento & desarrollo , Magnoliopsida/metabolismo , Magnoliopsida/fisiología , Flores/crecimiento & desarrollo , Flores/metabolismo , Desarrollo de la Planta/efectos de los fármacos
16.
Sci Rep ; 14(1): 13718, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877059

RESUMEN

In their natural environment, animals face a variety of ecological and social challenges, which might be linked to the emergence of different cognitive skills. To assess inter-specific variation in cognitive skills, we used ungulates as a study model, testing a total of 26 captive individuals across 5 different species (i.e., dwarf goats, Capra aegagrus hircus, llamas, Lama glama, guanacos, Lama guanicoe, zebras, Equus grevyi, and rhinos, Diceros bicornis michaeli). Across species, we used the same well-established experimental procedures to test individuals' performance in naïve physics tasks, i.e. object permanence, short-term spatial memory, causality, understanding of object properties, and gravity. Our results revealed that study subjects showed object permanence, were able to remember the position of hidden food after up to 60 s, and inferred the position of hidden food from the sound produced or not produced when shaking containers. Moreover, they showed an understanding of basic object properties, being able to locate objects hidden behind occluders based on their size and inclination, and could reliably follow the trajectory of falling objects across different conditions. Finally, inter-specific differences were limited to the understanding of object properties, and suggest that domesticated species as goats might perform better than non-domesticated ones in tasks requiring these skills. These results provide new information on the cognitive skills of a still understudied taxon and confirm ungulates as a promising taxon for the comparative study of cognitive evolution.


Asunto(s)
Memoria Espacial , Animales , Memoria Espacial/fisiología , Masculino , Femenino , Cabras/fisiología , Memoria a Corto Plazo/fisiología , Cognición/fisiología , Gravitación , Especificidad de la Especie , Camélidos del Nuevo Mundo/fisiología
17.
Cereb Cortex ; 34(6)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38869374

RESUMEN

The central sulcus divides the primary motor and somatosensory cortices in many anthropoid primate brains. Differences exist in the surface area and depth of the central sulcus along the dorso-ventral plane in great apes and humans compared to other primate species. Within hominid species, there are variations in the depth and aspect of their hand motor area, or knob, within the precentral gyrus. In this study, we used post-image analyses on magnetic resonance images to characterize the central sulcus shape of humans, chimpanzees (Pan troglodytes), gorillas (Gorilla gorilla), and orangutans (Pongo pygmaeus and Pongo abelii). Using these data, we examined the morphological variability of central sulcus in hominids, focusing on the hand region, a significant change in human evolution. We show that the central sulcus shape differs between great ape species, but all show similar variations in the location of their hand knob. However, the prevalence of the knob location along the dorso-ventral plane and lateralization differs between species and the presence of a second ventral motor knob seems to be unique to humans. Humans and orangutans exhibit the most similar and complex central sulcus shapes. However, their similarities may reflect divergent evolutionary processes related to selection for different positional and habitual locomotor functions.


Asunto(s)
Evolución Biológica , Gorilla gorilla , Hominidae , Imagen por Resonancia Magnética , Corteza Motora , Pan troglodytes , Filogenia , Animales , Humanos , Masculino , Pan troglodytes/anatomía & histología , Pan troglodytes/fisiología , Gorilla gorilla/anatomía & histología , Gorilla gorilla/fisiología , Femenino , Corteza Motora/anatomía & histología , Corteza Motora/fisiología , Corteza Motora/diagnóstico por imagen , Hominidae/anatomía & histología , Hominidae/fisiología , Adulto , Mano/fisiología , Mano/anatomía & histología , Adulto Joven , Pongo pygmaeus/anatomía & histología , Pongo pygmaeus/fisiología , Especificidad de la Especie , Pongo abelii/anatomía & histología , Pongo abelii/fisiología
18.
Ecol Evol Physiol ; 97(3): 180-189, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38875137

RESUMEN

AbstractDuring periods of torpor, hibernators can reduce metabolic rate (MR) and body temperature (Tb) substantially. However, to avoid physiological dysfunction at low temperatures, they defend Tb at a critical minimum, often between ~0°C and 10°C via an increase in MR. Because thermoregulation during torpor requires extra energy, individuals with lower Tb's and thus minimal MR during torpor should be selected in colder climates. Such inter- and intraspecific variations occur in some placental mammals, but for the evolutionary separate marsupials, available information is scarce. Marsupial eastern pygmy possums (Cercartetus nanus; ~22 g body mass), widely distributed along the Australian southeastern coast including subtropical to alpine areas, were used to test the hypothesis that the defended Tb of torpid individuals is related to the climate of their habitat. Possums were captured from five regions, 1,515 km apart, with midwinter (July) minimum environmental temperatures (min Tenv's) ranging from -3.9°C to 6.6°C. Captive possums in deep torpor were slowly cooled with ambient temperature (Ta), while their MR was measured to determine the minimum torpor metabolic rate (TMR), the Ta at which their MR increased for thermoregulation (min Ta), and the corresponding minimum Tb (min Tb). Partial least squares regression analysis revealed that Ta and Tenv were the strongest explanatory variables for the min Tb. The min Tb and Ta were also correlated with latitude but not elevation of the capture sites. However, the best correlations were observed between the min Tenv and the min Tb and Ta for individuals experiencing min Tenv>0°C; these individuals thermoconformed to min Ta's between -0.8°C and 3.7°C, and their min Tb ranged from 0.5°C to 6.0°C and was 0.5°C-2.6°C below the min Tenv at the capture site. In contrast, individuals experiencing a min Tenv of -3.9°C regulated Tb at 0.6°C±0.2°C or 4.5°C above the Tenv. The minimum TMR of all possums did not differ with Ta and thus did not differ among populations and was 2.6% of the basal MR. These data provide new evidence that thermal variables of marsupials are subject to regional intraspecific variation. It suggests that min Tb is a function of the min Tenv but only above 0°C, perhaps because the Tb-Ta differential for torpid possums in the wild, at a min Tenv of -3.9°C, remains small enough to be compensated by a small increase in MR and does not require the physiological capability for a reduction of Tb below 0°C.


Asunto(s)
Regulación de la Temperatura Corporal , Animales , Regulación de la Temperatura Corporal/fisiología , Metabolismo Basal/fisiología , Hibernación/fisiología , Marsupiales/fisiología , Australia , Temperatura Corporal/fisiología , Temperatura , Especificidad de la Especie , Femenino
19.
J Zoo Wildl Med ; 55(2): 301-312, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38875187

RESUMEN

The wild rhinoceros populations have declined drastically in the past decades because the rhinoceros are heavily hunted for their horns. Zoological institutions aim to conserve rhinoceros populations in captivity, but one of the challenges of ex situ conservation is to provide food sources that resemble those available in the wild. Considering that the mammalian gut microbiota is a pivotal player in their host's health, the gut microbiota of rhinoceros may also play a role in the bioavailability of nutrients. Therefore, this study aims to characterize the fecal microbiome composition of grazing white rhinoceros (WR; Ceratotherium simum) and greater one-horned rhinoceros (GOHR; Rhinoceros unicornis) as well as the browsing black rhinoceros (BR; Diceros bicornis) kept in European zoos. Over the course of 1 yr, 166 fecal samples in total were collected from 9 BR (n = 39), 10 GOHR (n = 56), and 14 WR (n = 71) from 23 zoological institutions. The bacterial composition in the samples was determined using 16S rRNA gene Illumina sequencing. The fecal microbiomes of rhinoceros clustered by species, with BR clustering more distantly from GOHR and WR. Furthermore, the data report clustering of rhinoceros microbiota according to individual rhinoceros and institutional origin, showing that zoological institutions play a significant role in shaping the gut microbiome of rhinoceros species. In addition, BR exhibit a relatively higher microbial diversity than GOHR and WR. BR seem more susceptible to microbial gut changes and appear to have a more diverse microbiome composition among individuals than GOHR and WR. These data expand on the role of gut microbes and can provide baseline data for continued efforts in rhinoceros conservation and health status.


Asunto(s)
Animales de Zoológico , Microbioma Gastrointestinal , Perisodáctilos , Animales , Perisodáctilos/microbiología , Animales de Zoológico/microbiología , Europa (Continente) , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/genética , Especificidad de la Especie , Heces/microbiología , ARN Ribosómico 16S/genética , ARN Bacteriano/genética
20.
Harmful Algae ; 136: 102624, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38876524

RESUMEN

This study aimed to explore the effects of different light intensities on the ecophysiology of eight new Dinophysis isolates comprising four species (D. acuminata, D. ovum, D. fortii, and D. caudata) collected from different geographical regions in the US. After six months of acclimation, the growth rates, photosynthetic efficiency (Fv/Fm ratio), toxin content, and net toxin production rates of the Dinophysis strains were examined. The growth rates of D. acuminata and D. ovum isolates were comparable across light intensities, with the exception of one D. acuminata strain (DANY1) that was unable to grow at the lowest light intensity. However, D. fortii and D. caudata strains were photoinhibited and grew at a slower rate at the highest light intensity, indicating a lower degree of adaptability and tolerance to such conditions. Photosynthetic efficiency was similar for all Dinophysis isolates and negatively correlated with exposure to high light intensities. Multiple toxin metrics, including cellular toxin content and net production rates of DSTs and PTXs, were variable among species and even among isolates of the same species in response to light intensity. A pattern was detected, however, whereby the net production rates of PTXs were significantly lower across all Dinophysis isolates when exposed to the lowest light intensity. These findings provide a basis for understanding the effects of light intensity on the eco-physiological characteristics of Dinophysis species in the US and could be employed to develop integrated physical-biological models for species and strains of interest to predict their population dynamics and mitigate their negative effects.


Asunto(s)
Dinoflagelados , Luz , Fotosíntesis , Dinoflagelados/fisiología , Dinoflagelados/efectos de la radiación , Aclimatación , Toxinas Marinas , Especificidad de la Especie
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