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1.
Annu Rev Entomol ; 69: 355-373, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-37758223

RESUMO

Global trade in fresh fruit and vegetables, intensification of human mobility, and climate change facilitate fruit fly (Diptera: Tephritidae) invasions. Life-history traits, environmental stress response, dispersal stress, and novel genetic admixtures contribute to their establishment and spread. Tephritids are among the most frequently intercepted taxa at ports of entry. In some countries, supported by the rules-based trade framework, a remarkable amount of biosecurity effort is being arrayed against the range expansion of tephritids. Despite this effort, fruit flies continue to arrive in new jurisdictions, sometimes triggering expensive eradication responses. Surprisingly, scant attention has been paid to biosecurity in the recent discourse about new multilateral trade agreements. Much of the available literature on managing tephritid invasions is focused on a limited number of charismatic (historically high-profile) species, and the generality of many patterns remains speculative.


Assuntos
Drosophila , Características de História de Vida , Animais , Humanos , Mudança Climática , Nonoxinol
2.
Bull Entomol Res ; : 1-11, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38817001

RESUMO

Two fruit fly (Diptera: Tephritidae) species of economic importance: Ceratitis rosa Karsch and Ceratitis quilicii De Meyer, Mwatawala & Virgilio are present in South Africa. The two species were considered as one species prior to 2016, but were subsequently separated. In this study, the distribution and abundance of the two species were quantified in seven provinces in South Africa through trapping with Enriched Ginger Oil as an attractant. Trapping was conducted over three seasons across two years (2020 and 2021): late summer, autumn-winter, and spring-early summer. Host ranges of the two species were investigated by fruit sampling in and outside of trapping sites. Ceratitis quilicii was more widely distributed than C. rosa with the latter being recorded in only three north-eastern provinces. There were geographical limits for both species with no records of them in Northern Cape Province. Catches of C. quilicii were higher in summer with average temperatures varying from 15 to 27°C while for C. rosa, catches remained low and consistent between seasons. Ceratitis quilicii catches decreased at lower rates than those of C. rosa at temperatures below 15°C. The two species were reared from 13 plant species from nine families. Four of these hosts were infested by both C. quilicii and C. rosa in the same province where they occurred. Preferred hosts of the two species belonged to the Myrtaceae family. The characterisation of the distribution, abundance and host ranges of these pests will provide a baseline for pest status determination and implementation of management actions.

3.
J Hum Evol ; 179: 103355, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37003245

RESUMO

Because the ulna supports and transmits forces during movement, its morphology can signal aspects of functional adaptation. To test whether, like extant apes, some hominins habitually recruit the forelimb in locomotion, we separate the ulna shaft and ulna proximal complex for independent shape analyses via elliptical Fourier methods to identify functional signals. We examine the relative influence of locomotion, taxonomy, and body mass on ulna contours in Homo sapiens (n = 22), five species of extant apes (n = 33), two Miocene apes (Hispanopithecus and Danuvius), and 17 fossil hominin specimens including Sahelanthropus, Ardipithecus, Australopithecus, Paranthropus, and early Homo. Ulna proximal complex contours correlate with body mass but not locomotor patterns, while ulna shafts significantly correlate with locomotion. African apes' ulna shafts are more robust and curved than Asian apes and are unlike other terrestrial mammals (including other primates), curving ventrally rather than dorsally. Because this distinctive curvature is absent in orangutans and hylobatids, it is likely a function of powerful flexors engaged in wrist and hand stabilization during knuckle-walking, and not an adaptation to climbing or suspensory behavior. The OH 36 (purported Paranthropus boisei) and TM 266 (assigned to Sahelanthropus tchadensis) fossils differ from other hominins by falling within the knuckle-walking morphospace, and thus appear to show forelimb morphology consistent with terrestrial locomotion. Discriminant function analysis classifies both OH 36 and TM 266 with Pan and Gorilla with high posterior probability. Along with its associated femur, the TM 266 ulna shaft contours and its deep, keeled trochlear notch comprise a suite of traits signaling African ape-like quadrupedalism. While implications for the phylogenetic position and hominin status of S. tchadensis remain equivocal, this study supports the growing body of evidence indicating that S. tchadensis was not an obligate biped, but instead represents a late Miocene hominid with knuckle-walking adaptations.


Assuntos
Hominidae , Animais , Hominidae/anatomia & histologia , Fósseis , Filogenia , Caminhada , Locomoção , Ulna/anatomia & histologia , Gorilla gorilla , Evolução Biológica , Mamíferos
4.
Ecol Appl ; 33(4): e2854, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37032063

RESUMO

As the climate changes, it is increasingly important to understand how forests will respond to drought and how forest management can influence those outcomes. In many forests that have become unnaturally dense, "restoration treatments," which decrease stand density using fire and/or mechanical thinning, are generally associated with reduced mortality during drought. However, the effects of such treatments on tree growth during drought are less clear. Previous studies have yielded apparently contradictory results, which may stem from differences in underlying aridity or drought intensity across studies. To address this uncertainty, we studied the growth of ponderosa pine (Pinus ponderosa) in paired treated and untreated areas before and during the extreme California drought of 2012-2016. Our study spanned gradients in climate and tree size and found that density reduction treatments could completely ameliorate drought-driven declines in growth under some contexts, specifically in more mesic areas and in medium-sized trees (i.e., normal annual precipitation > ca. 1100 mm and tree diameter at breast height < ca. 65 cm). Treatments were much less effective in ameliorating drought-associated growth declines in the most water-limited sites and largest trees, consistent with underlying ecophysiology. In medium-sized trees and wetter sites, growth of trees in untreated stands decreased by more than 15% during drought, while treatment-associated increases in growth of 25% or more persisted during the drought. Trees that ultimately died due to drought showed greater growth reductions during drought relative to trees that survived. Our results suggest that density reduction treatments can increase tree resistance to water stress, and they highlight an important pathway for treatments to influence carbon sequestration and other ecosystem services beyond mitigating tree mortality.


Assuntos
Resistência à Seca , Pinus ponderosa , Pinus ponderosa/fisiologia , Ecossistema , Florestas , Árvores/fisiologia , Secas
5.
Mol Phylogenet Evol ; 161: 107160, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33794396

RESUMO

The Ceratitis FARQ complex (formerly FAR complex) includes four frugivorous tephritids, Ceratitis fasciventris, C. anonae, C. rosa and C. quilicii, the latter two causing important agricultural losses in Africa. Although FARQ species can be identified on the basis of subtle morphological differences, they cannot be resolved as monophyletic when trying phylogenetic tree reconstructions based on mitochondrial or nuclear gene fragments except for microsatellites. In this study, we used mitogenome and genome-wide SNPs to investigate the phylogenetic relationship within the complex as well as between all four Ceratitis subgenera. The analysis of 13 species supported the monophyly of the Ceratitis subgenera Ceratitis, Ceratalaspis, Pardalaspis, and recovered Pterandrus as paraphyletic but could not properly resolve species within the FARQ complex. Conversely, gene and species tree reconstructions based on 785,484 genome-wide SNPs could consistently resolve the FARQ taxa and provide insights into their phylogenetic relationships. Gene flow was detected by TreeMix analysis from C. quilicii to C. fasciventris, suggesting the existence of introgression events in the FARQ complex. Our results suggest that genome-wide SNPs represent a suitable tool for the molecular diagnosis of FARQ species and could possibly be used to develop rapid diagnostic methods or to trace the origins of intercepted samples.


Assuntos
Filogenia , Tephritidae , Animais , Núcleo Celular/genética , Fluxo Gênico , Genes Mitocondriais/genética , Repetições de Microssatélites , Tephritidae/genética
6.
Ecol Appl ; 30(1): e02002, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31519065

RESUMO

Rising temperatures and more frequent and severe droughts are driving increases in tree mortality in forests around the globe. However, in many cases, the likely trajectories of forest recovery following drought-related mortality are poorly understood. In many fire-suppressed western U.S. forests, management is applied to reverse densification and restore natural forest structure and species composition, but it is unclear how such management affects post-mortality recovery. We addressed these uncertainties by examining forest stands that experienced mortality during the severe drought of 2012-2016 in California, USA. We surveyed post-drought vegetation along a gradient of overstory mortality severity in paired treated (mechanically thinned or prescribed-burned) and untreated areas in the Sierra Nevada. Treatment substantially reduced tree density, particularly in smaller tree size classes, and these effects persisted through severe drought-related overstory mortality. However, even in treated areas with severe mortality (>67% basal area mortality), the combined density of residual (surviving) trees (mean 44 trees/ha) and saplings (mean 189 saplings/ha) frequently (86% of plots) fell within or exceeded the natural range of variation (NRV) of tree density, suggesting little need for reforestation intervention to increase density. Residual tree densities in untreated high-mortality plots were significantly higher (mean 192 trees/ha and 506 saplings/ha), and 96% of these plots met or exceeded the NRV. Treatment disproportionately removed shade-tolerant conifer species, while mortality in the drought event was concentrated in pines (Pinus ponderosa and P. lambertiana); as a consequence, the residual trees, saplings, and seedlings in treated areas, particularly those that had experienced moderate or high drought-related mortality, were more heavily dominated by broadleaf ("hardwood") trees (particularly Quercus kelloggii and Q. chrysolepis). In contrast, residual trees and regeneration in untreated stands were heavily dominated by shade-tolerant conifer species (Abies concolor and Calocedrus decurrens), suggesting a need for future treatment. Because increased dominance of hardwoods brings benefits for plant and animal diversity and stand resilience, the ecological advantages of mechanical thinning and prescribed fire treatments may, depending on the management perspective, extend even to stands that ultimately experience high drought-related mortality following treatment.


Assuntos
Secas , Incêndios , Animais , California , Florestas , Árvores
7.
J Hum Evol ; 132: 189-214, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31203847

RESUMO

Australopitheus anamensis fossils demonstrate that craniodentally and postcranially the taxon was more primitive than its evolutionary successor Australopithecus afarensis. Postcranial evidence suggests habitual bipedality combined with primitive upper limbs and an inferred significant arboreal adaptation. Here we report on A. anamensis fossils from the Assa Issie locality in Ethiopia's Middle Awash area dated to ∼4.2 Ma, constituting the oldest known Australopithecus axial remains. Because the spine is the interface between major body segments, these fossils can be informative on the adaptation, behavior and our evolutionary understanding of A. anamensis. The atlas, or first cervical vertebra (C1), is similar in size to Homo sapiens, with synapomorphies in the articular facets and transverse processes. Absence of a retroglenoid tubercle suggests that, like humans, A. anamensis lacked the atlantoclavicularis muscle, resulting in reduced capacity for climbing relative to the great apes. The retroflexed C2 odontoid process and long C6 spinous process are reciprocates of facial prognathism, a long clivus and retroflexed foramen magnum, rather than indications of locomotor or postural behaviors. The T1 is derived in shape and size as in Homo with an enlarged vertebral body epiphyseal surfaces for mitigating the high-magnitude compressive loads of full-time bipedality. The full costal facet is unlike the extant great ape demifacet pattern and represents the oldest evidence for the derived univertebral pattern in hominins. These fossils augment other lines of evidence in A. anamensis indicating habitual bipedality despite some plesiomorphic vertebral traits related to craniofacial morphology independent of locomotor or postural behaviors (i.e., a long clivus and a retroflexed foramen magnum). Yet in contrast to craniodental lines of evidence, some aspects of vertebral morphology in A. anamensis appear more derived than its descendant A. afarensis.


Assuntos
Vértebras Cervicais/anatomia & histologia , Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Vértebras Torácicas/anatomia & histologia , Animais , Evolução Biológica , Etiópia
8.
Genome ; 62(10): 677-687, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31283887

RESUMO

The hoverfly genus Eristalinus (Diptera, Syrphidae) contains many widespread pollinators. The majority of the species of Eristalinus occur in the Afrotropics and their molecular systematics still needs to be investigated. This study presents the first complete and annotated mitochondrial genomes for five species of Eristalinus. They were obtained by high-throughput sequencing of total genomic DNA. The total length of the mitogenomes varied between 15 757 and 16 245 base pairs. Gene composition, positions, and orientation were shared across species, and were identical to those observed for other Diptera. Phylogenetic analyses (maximum likelihood and Bayesian inference) based on the 13 protein coding and both rRNA genes suggested that the subgenus Eristalinus was paraphyletic with respect to the subgenus Eristalodes. An analysis of the phylogenetic informativeness of all protein coding and rRNA genes suggested that NADH dehydrogenase subunit 5 (nad5), cytochrome c oxidase subunit 1, nad4, nad2, cytochrome b, and 16S rRNA genes are the most promising mitochondrial molecular markers to result in supported phylogenetic hypotheses of the genus. In addition to the five complete mitogenomes currently available for hoverflies, the five mitogenomes published here will be useful for broader molecular phylogenetic analyses among hoverflies.


Assuntos
Dípteros/genética , Genoma Mitocondrial , Animais , Teorema de Bayes , Dípteros/classificação , Funções Verossimilhança , Filogenia , Especificidade da Espécie
9.
Ecol Appl ; 29(4): e01902, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31020735

RESUMO

Extreme drought stress and associated bark beetle population growth contributed to an extensive tree mortality event in California, USA, resulting in more than 129 million trees dying between 2012 and 2016. Although drought is an important driver of this mortality event, past and ongoing fire suppression and the consequent densification of forests may have contributed. In some areas, land management agencies have worked to reduce stand density through mechanical treatments and prescribed fire to restore forests to less dense, more open conditions that are presumably more resilient to disturbance and changing climate. Here, we evaluate if stand structural conditions associated with treated (e.g., thinned and prescribed burned) forests in the Sierra Nevada of California conferred more resistance to the bark beetle epidemic and drought event of 2012-2016. We found that, compared to untreated units, treated units had lower stand densities, larger average tree diameters, and greater dominance of pines (Pinus), the historically dominant trees. For all tree species studied, mortality was substantially greater in climatically drier areas (i.e., lower elevations and latitudes). Both pine species studied (ponderosa pine [Pinus ponderosa] and sugar pine [Pinus lambertiana]) had greater mortality in areas where their diameters were larger, suggesting a size preference for their insect mortality agents. For ponderosa pine, the tree species experiencing greatest mortality, individual-tree mortality probability (for a given tree diameter) was significantly lower in treated stands. Ponderosa pine mortality was also positively related to density of medium- to large-sized conspecific trees, especially in areas with lower precipitation, suggesting that abundance of nearby host trees for insect mortality agents was an important determinant of pine mortality. Mortality of incense cedar (Calocedrus decurrens) and white fir (Abies concolor) was positively associated with basal area, suggesting sensitivity to competition during drought, but overall mortality was lower, likely because the most prevalent and effective mortality agents (the bark beetles Dendroctonus brevicomis and D. ponderosae) are associated specifically with pine species within our study region. Our findings suggest that forest thinning treatments are effective in reducing drought-related tree mortality in forests, and they underscore the important interaction between water and forest density in mediating bark beetle-caused mortality.


Assuntos
Secas , Pinus , Animais , California , Clima , Florestas , Nevada
10.
Clin Infect Dis ; 67(10): 1550-1558, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-29617742

RESUMO

Background: Colorado hospitals participated in a statewide collaborative to improve the management of inpatient urinary tract infections (UTIs) and skin and soft tissue infections (SSTIs). We evaluated the effects of the intervention on diagnostic accuracy and antibiotic use. Methods: The main collaborative outcomes were proportion of UTI diagnoses that met criteria for symptomatic UTI; exposure to fluoroquinolones (UTI only); duration of therapy (UTIs and SSTIs); and exposure to antibiotics with broad gram-negative activity (SSTIs only). Outcomes were compared between pre-intervention and intervention periods overall and by hospital. Secondary analyses were changes in outcome trends by time series analysis. Results: Twenty-six hospitals, including 9 critical access hospitals, participated in the collaborative. Data were reported for 4060 UTIs and 1759 SSTIs. Between the pre-intervention and intervention periods, the proportion of diagnosed UTIs that met criteria for symptomatic UTI was similar (51% vs 54%, respectively; P = .10), exposure to fluoroquinolones declined (49% vs 41%; P < .001), and the median duration of therapy was unchanged (7 vs 7 days; P = .99). Among SSTIs, exposure to antibiotics with broad gram-negative activity declined (61% vs 53%; P = .001) and the median duration of therapy declined (11 vs 10 days; P = .03). There was substantial variation in performance among hospitals. By time series analysis, only the declining trend of fluoroquinolone use was significant (P = .03). Conclusions: The collaborative model is a feasible approach to engage hospitals in a common antibiotic stewardship intervention. Performance improvement was observed for several outcomes but varied substantially by hospital.


Assuntos
Antibacterianos/uso terapêutico , Gestão de Antimicrobianos/métodos , Infecções dos Tecidos Moles/diagnóstico , Infecções dos Tecidos Moles/tratamento farmacológico , Infecções Urinárias/diagnóstico , Infecções Urinárias/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Colorado , Feminino , Fluoroquinolonas/uso terapêutico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Hospitais , Humanos , Colaboração Intersetorial , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Alzheimer Dis Assoc Disord ; 32(2): 89-93, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29261520

RESUMO

The diagnostic accuracy of hexamethylpropyleneamine oxime (HMPAo) single-photon emission computed tomography (SPECT) in Alzheimer disease (AD) remains undetermined in a "real-life" clinical population. The objective was to determine the HMPAo SPECT hypoperfusion pattern in cognitively impaired patients with positive CSF AD biomarker and to evaluate its diagnostic accuracy. This study included 120 patients referred to a university memory clinic assessed using HMPAo SPECT, MRI, and CSF biomarkers. Three biomarker signatures suggestive of AD were analyzed (1, Aß1-42; 2, Aß1-42+t-tau and/or p-tau; 3, Aß1-42/p-tau). The clinical diagnoses were possible AD (n=29) or other causes of cognitive impairment (n=91). All CSF AD signatures were significantly (1, P=0.004; 2, P=0.017; 3, P=0.024) associated with the difference between inferior parietal perfusion and lateral dorsal frontal cortex perfusion. The hypoperfusion pattern discriminated between patients with positive CSF AD biomarkers and those with other cognitive impairments with a sensitivity of 67% to 71% and a specificity of 63% to 65% and a greatest negative predictive value (NPV) of 90%. Inferior parietal cortex hypoperfusion was the most sensitive and specific feature in AD patients diagnosed using clinical and CSF biomarker criteria. This hypoperfusion pattern was associated with an NPV of 90% and therefore discriminated sharply between AD and other cognitive disorders.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Biomarcadores/líquido cefalorraquidiano , Lobo Parietal/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Feminino , França , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos
12.
Am J Phys Anthropol ; 166(3): 613-637, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29492962

RESUMO

OBJECTIVES: Uncinate processes are protuberances on the cranial surface of subaxial cervical vertebrae that assist in stabilizing and guiding spinal motion. Shallow uncinate processes reduce cervical stability but confer an increased range of motion in clinical studies. Here we assess uncinate processes among extant primates and model cervical kinematics in early fossil hominins. MATERIALS AND METHODS: We compare six fossil hominin vertebrae with 48 Homo sapiens and 99 nonhuman primates across 20 genera. We quantify uncinate morphology via geometric morphometric methods to understand how uncinate process shape relates to allometry, taxonomy, and mode of locomotion. RESULTS: Across primates, allometry explains roughly 50% of shape variation, as small, narrow vertebrae feature the relatively tallest, most pronounced uncinate processes, whereas larger, wider vertebrae typically feature reduced uncinates. Taxonomy only weakly explains the residual variation, however, the association between Uncinate Shape and mode of locomotion is robust, as bipeds and suspensory primates occupy opposite extremes of the morphological continuum and are distinguished from arboreal generalists. Like humans, Australopithecus afarensis and Homo erectus exhibit shallow uncinate processes, whereas A. sediba resembles more arboreal taxa, but not fully suspensory primates. DISCUSSION: Suspensory primates exhibit the most pronounced uncinates, likely to maintain visual field stabilization. East African hominins exhibit reduced uncinate processes compared with African apes and A. sediba, likely signaling different degrees of neck motility and modes of locomotion. Although soft tissues constrain neck flexibility beyond limits suggested by osteology alone, this study may assist in modeling cervical kinematics and positional behaviors in extinct taxa.


Assuntos
Vértebras Cervicais/anatomia & histologia , Hominidae/anatomia & histologia , Animais , Antropologia Física , Antropometria , Evolução Biológica , Fenômenos Biomecânicos , Vértebras Cervicais/fisiologia , Hominidae/fisiologia , Humanos , Locomoção/fisiologia , Pescoço/anatomia & histologia , Pescoço/fisiologia
13.
Clin Infect Dis ; 65(4): 691-696, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28472291

RESUMO

Antibiotic stewardship programs (ASPs) improve antibiotic prescribing. Seventy-three percent of US hospitals have <200 beds. Small hospitals (<200 beds) have similar rates of antibiotic prescribing compared to large hospitals, but the majority of small hospitals lack ASPs that satisfy the Centers for Disease Control and Prevention's core elements. All hospitals, regardless of size, are now required to have ASPs by The Joint Commission, and the Centers for Medicare and Medicaid Services has proposed a similar requirement. Very few studies have described the successful implementation of ASPs in small hospitals. We describe barriers commonly encountered in small hospitals when constructing an antibiotic stewardship team, obtaining appropriate metrics of antibiotic prescribing, implementing antibiotic stewardship interventions, obtaining financial resources, and utilizing the microbiology laboratory. We propose potential solutions that tailor stewardship activities to the needs of the facility and the resources typically available.


Assuntos
Gestão de Antimicrobianos , Hospitais Comunitários , Gestão de Antimicrobianos/economia , Gestão de Antimicrobianos/métodos , Gestão de Antimicrobianos/organização & administração , Gestão de Antimicrobianos/normas , Humanos , Padrões de Prática Médica
14.
J Hum Evol ; 104: 32-49, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28317555

RESUMO

Cervical vertebrae are rare in the early hominin fossil record, presenting a challenge for understanding the evolution of the neck and head carriage in hominin evolution. Here, we examine the cervical vertebrae of Australopithecus sediba, which unlike other South African taxa is known from associated cervical vertebrae. The A. sediba cervical vertebrae exhibit human-like values for wedging, pedicle cross-sectional areas, and articular facet heights, indicating reduced ventral loading relative to African apes. These features combine with a pattern of vertebral body bone distribution and caudally progressive size expansion suggesting a mode of cervical lordosis, load mitigation, and head carriage similar to humans and distinct from the cantilevered mode of head carriage of the extant African great apes. Yet these derived features in A. sediba are accompanied by ape-like vertebral body and dorsal pillar sizes, articular facet orientation, and uncinate process morphology signaling reduced lateral and rotational coupled movements between vertebral elements and indicate a considerably stiffer neck than in humans. A primitively long and horizontally-oriented C7 spinous process is likely related to a prognathic viscerocranium, although the complimentary C3 spinous process is short, implying large moments emanating from scapular and shoulder elevators rather than large muscles of head stabilization. Cross-sectional spinous process shape and robust anterior tubercles similarly signal increased arm elevation consistent with climbing behavior in corroboration with arboreal signatures previously observed in the shoulder, arms, and hand of A. sediba. Spinal canal shape and size suggests that A. sediba lacked the cervical spinal cord enlargement of Homo that confers humans with enhanced motor control to the upper limbs. The cervical spine of A. sediba thus presents a mosaic of primitive and derived characters, with anatomical features relating to neck posture and head carriage mirroring humans juxtaposed with most other aspects of functional anatomy that resemble chimpanzees.


Assuntos
Vértebras Cervicais/anatomia & histologia , Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Animais , Feminino , Masculino , África do Sul
15.
J Hum Evol ; 104: 136-154, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28094004

RESUMO

Hominin evolution featured shifts from a trunk shape suitable for climbing and housing a large gut to a trunk adapted to bipedalism and higher quality diets. Our knowledge regarding the tempo, mode, and context in which these derived traits evolved has been limited, based largely on a small-bodied Australopithecus partial skeleton (A.L. 288-1; "Lucy") and a juvenile Homo erectus skeleton (KNM-WT 15000; "Turkana Boy"). Two recent discoveries, of a large-bodied Australopithecus afarensis (KSD-VP-1/1) and two Australopithecus sediba partial skeletons (MH1 and MH2), have added to our understanding of thorax evolution; however, little is known about thorax morphology in early Homo. Here we describe hominin vertebrae, ribs, and sternal remains from the Dinaledi chamber of the Rising Star cave system attributed to Homo naledi. Although the remains are highly fragmented, the best-preserved specimens-two lower thoracic vertebrae and a lower rib-were found in association and belong to a small-bodied individual. A second lower rib may belong to this individual as well. All four of these individual elements are amongst the smallest known in the hominin fossil record. H. naledi is characterized by robust, relatively uncurved lower ribs and a relatively large spinal canal. We expect that the recovery of additional material from Rising Star Cave will clarify the nature of these traits and shed light on H. naledi functional morphology and phylogeny.


Assuntos
Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Costelas/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Animais , Evolução Biológica , África do Sul
16.
Annu Rev Entomol ; 61: 219-38, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26735644

RESUMO

Horticulture is one of the most important agricultural subsectors in Africa, providing income, creating employment opportunities, and enhancing food and nutritional security. However, tephritid fruit flies are responsible for both direct and indirect losses, with alien invasive species often having the most severe ecological and economic impact. In the past 20 years, systematic analysis of tephritids has provided comparative information on taxonomy, synonymy, and character-state differentiation. New molecular techniques are now available for identifying species, reconstructing phylogenies, and studying population genetic structures. Research on biology, host range and shifts, thermotolerance, and demography has provided useful information for developing predictive and ecological niche models to guide management methods. In recent years, the responses of various species to attractants have been documented. Several suppression methods, including the release of coevolved parasitoid species targeting invasives, have been promoted within the context of integrated pest management, leading to improvement in the quality and quantity of fruits and vegetables produced. However, there is still the need for wide-scale availability of these technologies to smallholder growers across Africa.


Assuntos
Controle de Insetos , Tephritidae/classificação , Tephritidae/fisiologia , África , Animais , Espécies Introduzidas
17.
BMC Evol Biol ; 16(1): 143, 2016 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-27357120

RESUMO

BACKGROUND: Anchored hybrid enrichment is a form of next-generation sequencing that uses oligonucleotide probes to target conserved regions of the genome flanked by less conserved regions in order to acquire data useful for phylogenetic inference from a broad range of taxa. Once a probe kit is developed, anchored hybrid enrichment is superior to traditional PCR-based Sanger sequencing in terms of both the amount of genomic data that can be recovered and effective cost. Due to their incredibly diverse nature, importance as pollinators, and historical instability with regard to subfamilial and tribal classification, Syrphidae (flower flies or hoverflies) are an ideal candidate for anchored hybrid enrichment-based phylogenetics, especially since recent molecular phylogenies of the syrphids using only a few markers have resulted in highly unresolved topologies. Over 6200 syrphids are currently known and uncovering their phylogeny will help us to understand how these species have diversified, providing insight into an array of ecological processes, from the development of adult mimicry, the origin of adult migration, to pollination patterns and the evolution of larval resource utilization. RESULTS: We present the first use of anchored hybrid enrichment in insect phylogenetics on a dataset containing 30 flower fly species from across all four subfamilies and 11 tribes out of 15. To produce a phylogenetic hypothesis, 559 loci were sampled to produce a final dataset containing 217,702 sites. We recovered a well resolved topology with bootstrap support values that were almost universally >95 %. The subfamily Eristalinae is recovered as paraphyletic, with the strongest support for this hypothesis to date. The ant predators in the Microdontinae are sister to all other syrphids. Syrphinae and Pipizinae are monophyletic and sister to each other. Larval predation on soft-bodied hemipterans evolved only once in this family. CONCLUSIONS: Anchored hybrid enrichment was successful in producing a robustly supported phylogenetic hypothesis for the syrphids. Subfamilial reconstruction is concordant with recent phylogenetic hypotheses, but with much higher support values. With the newly designed probe kit this analysis could be rapidly expanded with further sampling, opening the door to more comprehensive analyses targeting problem areas in syrphid phylogenetics and ecology.


Assuntos
Evolução Biológica , Dípteros/classificação , Animais , Dípteros/genética , Flores , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Polinização , Análise de Sequência de DNA
19.
FASEB J ; 29(7): 2980-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25854701

RESUMO

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of autosomal-dominant forms of Parkinson's disease. LRRK2 is a modular, multidomain protein containing 2 enzymatic domains, including a kinase domain, as well as several protein-protein interaction domains, pointing to a role in cellular signaling. Although enormous efforts have been made, the exact pathophysiologic mechanisms of LRRK2 are still not completely known. In this study, we used a chemical genetics approach to identify LRRK2 substrates from mouse brain. This approach allows the identification of substrates of 1 particular kinase in a complex cellular environment. Several of the identified peptides are involved in the regulation of microtubule (MT) dynamics, including microtubule-associating protein (MAP)/microtubule affinity-regulating kinase 1 (MARK1). MARK1 is a serine/threonine kinase known to phosphorylate MT-binding proteins such as Tau, MAP2, and MAP4 at KXGS motifs leading to MT destabilization. In vitro kinase assays and metabolic-labeling experiments in living cells confirmed MARK1 as an LRRK2 substrate. Moreover, we also showed that LRRK2 and MARK1 are interacting in eukaryotic cells. Our findings contribute to the identification of physiologic LRRK2 substrates and point to a potential mechanism explaining the reported effects of LRRK2 on neurite morphology.


Assuntos
Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Sequência de Aminoácidos , Animais , Encéfalo/metabolismo , Células HEK293 , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Camundongos , Camundongos Knockout , Microtúbulos/metabolismo , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
20.
Mol Phylogenet Evol ; 85: 171-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25681676

RESUMO

The phylogenetic relationships within and among subtribes of the fruit fly tribe Dacini (Ceratitidina, Dacina, Gastrozonina) were investigated by sequencing four mitochondrial and one nuclear gene fragment. Bayesian, maximum likelihood and maximum parsimony analyses were implemented on two datasets. The first, aiming at obtaining the strongest phylogenetic signal (yet, having lower taxon coverage), consisted of 98 vouchers and 2338 concatenated base pairs (bp). The second, aiming at obtaining the largest taxonomic coverage (yet, providing lower resolution), included 159 vouchers and 1200 concatenated bp. Phylogenetic relationships inferred by different tree reconstruction methods were largely congruent and showed a general agreement between concatenated tree topologies. Yet, local conflicts in phylogenetic signals evidenced a number of critical sectors in the phylogeny of Dacini fruit flies. All three Dacini subtribes were recovered as monophyletic. Yet, within the subtribe Ceratitidina only Perilampsis and Capparimyia formed well-resolved monophyletic groups while Ceratitis and Trirhithrum did not. Carpophthoromyia was paraphyletic because it included Trirhithrum demeyeri and Ceratitis connexa. Complex phylogenetic relationships and localised conflict in phylogenetic signals were observed within subtribe Dacina with (a) Dacus, (b) Bactrocera (Zeugodacus) and (c) all other Bactrocera species forming separate clades. The subgenus Bactrocera (Zeugodacus) is therefore raised to generic rank (Zeugodacus Hendel stat. nov.). Additionally, Bactrocera subgenera grouped under the Zeugodacus group should be considered under new generic combinations. Although there are indications that Zeugodacus and Dacus are sister groups, the exact relationship between Zeugodacus stat. nov., Dacus and Bactrocera still needs to be properly resolved.


Assuntos
Filogenia , Tephritidae/classificação , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Funções Verossimilhança , Análise de Sequência de DNA
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