Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 130
Filtrar
1.
Glob Chang Biol ; 30(1): e17074, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273545

RESUMO

Tropical regions contain ecologically and socio-economically important habitats, and are home to about 3.8 billion people, many of which directly depend on tropical coastal waters for their well-being. At the basis of these ecosystems are biogeochemical processes. Climate change is expected to have a greater impact in the tropics compared to temperate regions because of the relatively stable environmental conditions found there. However, it was surprising to find only 660 research articles published focusing on the impact of climate change on the biogeochemistry of coastal tropical waters compared to 4823 for temperate waters. In this perspective, we highlight important topics in need of further research. Specifically, we suggest that in tropical regions compared to temperate counterparts climate change stressors will be experienced differently, that organisms have a lower acclimation capacity, and that long-term baseline biogeochemical datasets useful for quantifying future changes are lacking. The low number of research papers on the impacts of climate change in coastal tropical regions is likely due to a mix of reasons including limited resources for research and limited number of long time series in many developing tropical countries. Finally, we propose some action points that we hope will stimulate more studies in tropical coastal waters.


Assuntos
Mudança Climática , Ecossistema , Humanos , Aclimatação , Clima Tropical
2.
Am J Primatol ; 86(5): e23603, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38293796

RESUMO

Identifying novel medicinal resources in chimpanzee diets has historically presented challenges, requiring extensive behavioral data collection and health monitoring, accompanied by expensive pharmacological analyses. When putative therapeutic self-medicative behaviors are observed, these events are often considered isolated occurrences, with little attention paid to other resources ingested in combination. For chimpanzees, medicinal resource combinations could play an important role in maintaining well-being by tackling different symptoms of an illness, chemically strengthening efficacy of a treatment, or providing prophylactic compounds that prevent future ailments. We call this concept the self-medicative resource combination hypothesis. However, a dearth of methodological approaches for holistically investigating primate feeding ecology has limited our ability to identify nonrandom resource combinations and explore potential synergistic relationships between medicinal resource candidates. Here we present two analytical tools that test such a hypothesis and demonstrate these approaches on feeding data from the Sonso chimpanzee community in Budongo Forest, Uganda. Using 4 months of data, we establish that both collocation and APRIORI analyses are effective exploratory tools for identifying binary combinations, and that APRIORI is effective for multi-item rule associations. We then compare outputs from both methods, finding up to 60% agreement, and propose APRIORI as more effective for studies requiring control over confidence intervals and those investigating nonrandom associations between more than two resources. These analytical tools, which can be extrapolated across the animal kingdom, can provide a cost-effective and efficient method for targeting resources for further pharmacological investigation, potentially aiding in the discovery of novel medicines.


Assuntos
Dieta , Pan troglodytes , Animais , Dieta/veterinária , Alimentos , Ecologia , Florestas , Uganda
3.
Bioscience ; 73(7): 494-512, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37560322

RESUMO

Managing marine nonindigenous species (mNIS) is challenging, because marine environments are highly connected, allowing the dispersal of species across large spatial scales, including geopolitical borders. Cross-border inconsistencies in biosecurity management can promote the spread of mNIS across geopolitical borders, and incursions often go unnoticed or unreported. Collaborative surveillance programs can enhance the early detection of mNIS, when response may still be possible, and can foster capacity building around a common threat. Regional or international databases curated for mNIS can inform local monitoring programs and can foster real-time information exchange on mNIS of concern. When combined, local species reference libraries, publicly available mNIS databases, and predictive modeling can facilitate the development of biosecurity programs in regions lacking baseline data. Biosecurity programs should be practical, feasible, cost-effective, mainly focused on prevention and early detection, and be built on the collaboration and coordination of government, nongovernment organizations, stakeholders, and local citizens for a rapid response.

4.
J Hum Evol ; 180: 103385, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37229946

RESUMO

During the middle Pliocene (∼3.8-3.2 Ma), both Australopithecus afarensis and Kenyanthropus platyops are known from the Turkana Basin, but between 3.60 and 3.44 Ma, most hominin fossils are found on the west side of Lake Turkana. Here, we describe a new hominin locality (ET03-166/168, Area 129) from the east side of the lake, in the Lokochot Member of the Koobi Fora Formation (3.60-3.44 Ma). To reconstruct the paleoecology of the locality and its surroundings, we combine information from sedimentology, the relative abundance of associated mammalian fauna, phytoliths, and stable isotopes from plant wax biomarkers, pedogenic carbonates, and fossil tooth enamel. The combined evidence provides a detailed view of the local paleoenvironment occupied by these Pliocene hominins, where a biodiverse community of primates, including hominins, and other mammals inhabited humid, grassy woodlands in a fluvial floodplain setting. Between <3.596 and 3.44 Ma, increases in woody vegetation were, at times, associated with increases in arid-adapted grasses. This suggests that Pliocene vegetation included woody species that were resilient to periods of prolonged aridity, resembling vegetation structure in the Turkana Basin today, where arid-adapted woody plants are a significant component of the ecosystem. Pedogenic carbonates indicate more woody vegetation than other vegetation proxies, possibly due to differences in temporospatial scale and ecological biases in preservation that should be accounted for in future studies. These new hominin fossils and associated multiproxy paleoenvironmental indicators from a single locale through time suggest that early hominin species occupied a wide range of habitats, possibly including wetlands within semiarid landscapes. Local-scale paleoecological evidence from East Turkana supports regional evidence that middle Pliocene eastern Africa may have experienced large-scale, climate-driven periods of aridity. This information extends our understanding of hominin environments beyond the limits of simple wooded, grassy, or mosaic environmental descriptions.


Assuntos
Hominidae , Animais , Ecossistema , Fósseis , Biodiversidade , Plantas , Mamíferos , Poaceae , Carbonatos , Evolução Biológica , Quênia
5.
Plant Cell Environ ; 45(2): 528-541, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34773419

RESUMO

The reasons underlying the differential tolerance of Actinidia spp. to the pandemic pathogen Pseudomonas syringae pv. actinidiae (Psa) have not yet been elucidated. We hypothesized that differential plant-defence strategies linked to transcriptome regulation, phytohormones and primary metabolism might be key and that Actinidia chinensis susceptibility results from an inefficient activation of defensive mechanisms and metabolic impairments shortly following infection. Here, 48 h postinoculation bacterial density was 10-fold higher in A. chinensis var. deliciosa than in Actinidia arguta, accompanied by significant increases in glutamine, ornithine, jasmonic acid (JA) and salicylic acid (SA) (up to 3.2-fold). Actinidia arguta showed decreased abscisic acid (ABA) (0.7-fold), no changes in primary metabolites, and 20 defence-related genes that were only differentially expressed in this species. These include GLOX1, FOX1, SN2 and RBOHA, which may contribute to its higher tolerance. Results suggest that A. chinensis' higher susceptibility to Psa is due to an inefficient activation of plant defences, with the involvement of ABA, JA and SA, leading to impairments in primary metabolism, particularly the ammonia assimilation cycle. A schematic overview on the interaction between Psa and genotypes with distinct tolerance is provided, highlighting the key transcriptomic and metabolomic aspects contributing to the different plant phenotypes after infection.


Assuntos
Actinidia/fisiologia , Interações entre Hospedeiro e Microrganismos , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/metabolismo , Pseudomonas syringae/fisiologia , Actinidia/microbiologia , Imunidade Vegetal/fisiologia
6.
Environ Monit Assess ; 194(6): 450, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35608726

RESUMO

Sand samples were collected from four beaches near a cement factory in Ras Baridi, north of Yanbu, which hosts the largest green turtle rookery in Saudi Arabia. Heavy metal concentrations (Cd, Pb, Fe, Cr, Ni, Se, Sb, As, and Cu) were measured at three different depths. For most elements, there were no significant differences in concentrations among depths; however, significant differences were found among the nesting beaches in Ras Baridi, which were likely influenced by the wind direction from the factory. Fe, Cr, Cu, and Ni had elevated contamination factor values, suggesting that the nesting beaches downwind and adjacent to the cement factory contained moderately contaminated sand. Given the possibility of heavy metals being absorbed through eggshells, there is a potential risk of heavy metal contamination in clutches laid in Ras Baridi. The rising threat to the local ecology in Saudi Arabia due to recent coastal developments for tourism projects highlights the importance of monitoring heavy metal concentrations over time.


Assuntos
Metais Pesados , Tartarugas , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Metais Pesados/toxicidade , Medição de Risco , Areia , Arábia Saudita , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
7.
Glob Chang Biol ; 27(17): 3956-3968, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34021662

RESUMO

Intensified coastal development is compromising the health and functioning of marine ecosystems. A key example of this is the Red Sea, a biodiversity hotspot subjected to increasing local human pressures. While some marine-protected areas (MPAs) were placed to alleviate these stressors, it is unclear whether these MPAs are managed or enforced, thus providing limited protection. Yet, most importantly, MPAs in the Red Sea were not designed using climate considerations, likely diminishing their effectiveness against global stressors. Here, we propose to tailor the design of MPAs in the Red Sea by integrating approaches to enhance climate change mitigation and adaptation. First, including coral bleaching susceptibility could produce a more resilient network of MPAs by safeguarding reefs from different thermal regions that vary in spatiotemporal bleaching responses, reducing the risk that all protected reefs will bleach simultaneously. Second, preserving the basin-wide genetic connectivity patterns that are assisted by mesoscale eddies could further ensure recovery of sensitive populations and maintain species potential to adapt to environmental changes. Finally, protecting mangrove forests in the northern and southern Red Sea that act as major carbon sinks could help offset greenhouse gas emissions. If implemented with multinational cooperation and concerted effort among stakeholders, our portfolio of climate-tailored approaches may help build a network of MPAs in the Red Sea that protects more effectively its coastal resources against escalating coastal development and climate instability. Beyond the Red Sea, we anticipate this study to serve as an example of how to improve the utility of tropical MPAs as climate-informed conservation tools.


Assuntos
Antozoários , Ecossistema , Animais , Biodiversidade , Conservação dos Recursos Naturais , Recifes de Corais , Humanos , Oceano Índico
8.
Physiol Plant ; 173(1): 235-245, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33629743

RESUMO

Iron (Fe) deficiency chlorosis (IDC) affects the growth of several crops, especially when growing in alkaline soils. The application of synthetic Fe-chelates is one of the most commonly used strategies in IDC amendment, despite their associated negative environmental impacts. In a previous work, the Fe-chelate tris(3-hydroxy-1-(H)-2-methyl-4-pyridinonate) iron(III) [Fe(mpp)3 ] has shown great potential for alleviating IDC in soybean (Glycine max) in the early stages of plant development under hydroponic conditions. Herein, its efficacy was verified under soil conditions in soybean grown from seed to full maturity. Chlorophyll levels, plant growth, root and shoot mineral accumulation (K, Mg, Ca, Na, P, Mn, Zn, Ni, and Co) and FERRITIN expression were accessed at V5 phenological stage. Compared to a commonly used Fe chelate, FeEDDHA, supplementation with [Fe(mpp)3 ] led to a 29% higher relative chlorophyll content, 32% higher root biomass, 36% higher trifoliate Fe concentration, and a twofold increase in leaf FERRITIN gene expression. [Fe(mpp)3 ] supplementation also resulted in increased accumulation of P, K, Zn, and Co. At full maturity, the remaining plants were harvested and [Fe(mpp)3 ] application led to a 32% seed yield increase when compared to FeEDDHA. This is the first report on the use of [Fe(mpp)3 ] under alkaline soil conditions for IDC correction, and we show that its foliar application has a longer-lasting effect than FeEDDHA, induces efficient root responses, and promotes the uptake of other nutrients.


Assuntos
Anemia Hipocrômica , Glycine max , Ferro , Raízes de Plantas , Piridonas
9.
Pain Med ; 22(12): 3051-3061, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33760046

RESUMO

OBJECTIVES: This was a pilot study to evaluate the feasibility and impact of a single dog-assisted therapy (cynotherapy) session in reducing pain and emotional distress in oncological outpatients compared with typical waiting room experience (control). DESIGN: This was a quasi-experimental before-after controlled study that took place at a chronic pain outpatient clinic of a tertiary cancer center, whose participants were adult oncological patients, able to consent and without medical contraindication. SETTING: Chronic pain outpatient clinic of a tertiary cancer center. PARTICIPANTS: Adult oncological patients able to consent and without medical contraindication. METHODS: All participants completed self-reported questionnaires including a numeric rating scale for pain and distress thermometer at admission and immediately before departure from the clinic. RESULTS: Eighty-one patients were enrolled over a 10-month study period, 41 in the cynotherapy group and 40 controls. Improvement was greater in cynotherapy than control group for pain (median difference score = -1.0 vs 0.0; P = 0.037), distress levels (median = -1.0 vs 0.0; P = 0.017), and depression (median = -1.0 vs 0.0; P = 0.030). The proportion of patients with a clinically relevant improvement in pain (reduction ≥2 points) was approximately twofold in the cynotherapy group when compared with controls, although not statistically significant (39% vs 20%, odds ratio = 2.53, 95% confidence interval = 0.86-8.02; P = 0.088). The mean satisfaction rate was 9.3/10, and no negative occurrences were reported. CONCLUSION: A single session of dog-assisted therapy can provide immediate improvement in the perception of pain and distress for patients with chronic cancer pain in an outpatient setting, with high satisfaction rates and no negative occurrences. This nonrandomized pilot study points toward the clinical relevance of implementing cynotherapy at a cancer pain clinic and developing a larger scale, more directed study.


Assuntos
Dor do Câncer , Neoplasias , Assistência Ambulatorial , Animais , Dor do Câncer/terapia , Cães , Humanos , Neoplasias/complicações , Dor/etiologia , Manejo da Dor , Projetos Piloto
10.
Mol Ecol ; 29(24): 4882-4897, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33063375

RESUMO

Autonomous Reef Monitoring Structures (ARMS) have been applied worldwide to characterize the critical yet frequently overlooked biodiversity patterns of marine benthic organisms. In order to disentangle the relevance of environmental factors in benthic patterns, here, through standardized metabarcoding protocols, we analyse sessile and mobile (<2 mm) organisms collected using ARMS deployed across six regions with different environmental conditions (3 sites × 3 replicates per region): Baltic, Western Mediterranean, Adriatic, Black and Red Seas, and the Bay of Biscay. A total of 27,473 Amplicon Sequence Variants (ASVs) were observed ranging from 1,404 in the Black Sea to 9,958 in the Red Sea. No ASVs were shared among all regions. The highest number of shared ASVs was between the Western Mediterranean and the Adriatic Sea (116) and Bay of Biscay (115). Relatively high numbers of ASVs (103), mostly associated with the genus Amphibalanus, were also shared between the lower salinity seas (Baltic and Black Seas). We found that compositional differences in spatial patterns of rocky-shore benthos are determined slightly more by dispersal limitation than environmental filtering. Dispersal limitation was similar between sessile and mobile groups, while the sessile group had a larger environmental niche breadth than the mobile group. Further, our study can provide a foundation for future evaluations of biodiversity patterns in the cryptobiome, which can contribute up to 70% of the local biodiversity.


Assuntos
Organismos Aquáticos , Biodiversidade , Mar Negro , Ecossistema , Monitoramento Ambiental , Oceano Índico
11.
J Hum Evol ; 140: 102717, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31916996

RESUMO

Australopithecus anamensis is a pivotal species in human evolution. It is likely to be the direct ancestor of Australopithecus afarensis and the species that may have given rise to the Homo and Paranthropus lineages. It had a suite of adaptations for habitual bipedalism and a diet that differed from that of earlier hominin species. Under what environmental and ecological conditions did this suite of adaptations arise? The early Pliocene site of Kanapoi in the Lake Turkana Basin of Kenya has the largest sample of A. anamensis in eastern Africa and a rich record of fossil vertebrates. Most Kanapoi fossils are chronologically well constrained by radiometrically dated tephras between the ages of 4.2 and 4.1 million years ago. Sedimentological, isotopic, and faunal data indicate that the environments of Kanapoi during the early Pliocene had a complex range of vegetation types that included closed woodlands, shrubs, and grasslands near a river (for most of the sequence) or lake. These were dynamic landscapes that could shift rapidly from fluvial to lacustrine conditions, and then back. Australopithecus anamensis shared its environments with at least 10 species of very large herbivores, which undoubtedly played a major role in modifying the landscape by opening wooded areas and providing pathways for bipedal hominins. Hominins may have competed for terrestrial resources with abundant suids (Nyanzachoerus and Notochoerus) and for arboreal resources with monkeys (Parapapio being the most common cercopithecid). Kanapoi had a formidable group of predators that included a very abundant species of hyena (Parahyaena howelli), two sabre-tooth felids (Dinofelis and Homotherium), a giant otter (Enhydriodon cf. dikikae), and three species of crocodiles. Various measures of abundance indicate that A. anamensis was an important component of the Kanapoi early Pliocene ecosystems, and that its key adaptations allowed this species to thrive in complex and dynamic landscapes.


Assuntos
Evolução Biológica , Hominidae/fisiologia , Características de História de Vida , Animais , Fósseis , Quênia
12.
BMC Ecol ; 20(1): 61, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228627

RESUMO

BACKGROUND: Tropical habitats and their associated environmental characteristics play a critical role in shaping macroinvertebrate communities. Assessing patterns of diversity over space and time and investigating the factors that control and generate those patterns is critical for conservation efforts. However, these factors are still poorly understood in sub-tropical and tropical regions. The present study applied a combination of uni- and multivariate techniques to test whether patterns of biodiversity, composition, and structure of macrobenthic assemblages change across different lagoon habitats (two mangrove sites; two seagrass meadows with varying levels of vegetation cover; and an unvegetated subtidal area) and between seasons and years. RESULTS: In total, 4771 invertebrates were identified belonging to 272 operational taxonomic units (OTUs). We observed that macrobenthic lagoon assemblages are diverse, heterogeneous and that the most evident biological pattern was spatial rather than temporal. To investigate whether macrofaunal patterns within the lagoon habitats (mangrove, seagrass, unvegetated area) changed through the time, we analysed each habitat separately. The results showed high seasonal and inter-annual variability in the macrofaunal patterns. However, the seagrass beds that are characterized by variable vegetation cover, through time, showed comparatively higher stability (with the lowest values of inter-annual variability and a high number of resident taxa). These results support the theory that seagrass habitat complexity promotes diversity and density of macrobenthic assemblages. Despite the structural and functional importance of seagrass beds documented in this study, the results also highlighted the small-scale heterogeneity of tropical habitats that may serve as biodiversity repositories. CONCLUSIONS: Comprehensive approaches at the "seascape" level are required for improved ecosystem management and to maintain connectivity patterns amongst habitats. This is particularly true along the Saudi Arabian coast of the Red Sea, which is currently experiencing rapid coastal development. Also, considering the high temporal variability (seasonal and inter-annual) of tropical shallow-water habitats, monitoring and management plans must include temporal scales.


Assuntos
Biodiversidade , Ecossistema , Animais , Oceano Índico , Invertebrados , Arábia Saudita
13.
Proc Biol Sci ; 286(1896): 20182697, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30963940

RESUMO

In an era of coral reef degradation, our knowledge of ecological patterns in reefs is biased towards large conspicuous organisms. The majority of biodiversity, however, inhabits small cryptic spaces within the framework of the reef. To assess this biodiverse community, which we term the 'reef cryptobiome', we deployed 87 autonomous reef monitoring structures (ARMS), on 22 reefs across 16 degrees latitude of the Red Sea. Combining ARMS with metabarcoding of the mitochondrial cytochrome oxidase I gene, we reveal a rich community, including the identification of 14 metazoan phyla within 10 416 operational taxonomic units (OTUs). While mobile and sessile subsets were similarly structured along the basin, the main environmental driver was different (particulate organic matter and sea surface temperature, respectively). Distribution patterns of OTUs showed that only 1.5% were present in all reefs, while over half were present in a single reef. On both local and regional scales, the majority of OTUs were rare. The high heterogeneity in community patterns of the reef cryptobiome has implications for reef conservation. Understanding the biodiversity patterns of this critical component of reef functioning will enable a sound knowledge of how coral reefs will respond to future anthropogenic impacts.


Assuntos
Biodiversidade , Recifes de Corais , Código de Barras de DNA Taxonômico , Animais , Complexo IV da Cadeia de Transporte de Elétrons/análise , Oceano Índico , Características de História de Vida , Proteínas Mitocondriais/análise , Arábia Saudita
14.
Mol Ecol ; 28(15): 3496-3507, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31281998

RESUMO

Autonomous Reef Monitoring Structures (ARMS) have been applied worldwide to describe eukaryotic cryptic reef fauna. Conversely, bacterial communities, which are critical components of coral reef ecosystem functioning, remain largely overlooked. Here we deployed 56 ARMS across the 2,000-km spread of the Red Sea to assay biodiversity, composition and inferred underlying functions of coral reef-associated bacterial communities via 16S rRNA gene sequencing. We found that bacterial community structure and diversity aligned with environmental differences. Indeed, sea surface temperature and macroalgae cover were key in explaining bacterial relative abundance. Importantly, taxonomic and functional alpha diversity decreased under more extreme environmental conditions (e.g., higher temperatures) in the southern Red Sea. This may imply a link between bacterial community diversity and functional capabilities, with implications for conservation management. Our study demonstrates the utility of ARMS to investigate the response of coral reef-associated bacterial communities to environmental change.


Assuntos
Recifes de Corais , Monitoramento Ambiental , Microbiota , Oceano Índico
15.
Glob Chang Biol ; 25(12): 4131-4146, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31482629

RESUMO

Global climate change has profound implications on species distributions and ecosystem functioning. In the coastal zone, ecological responses may be driven by various biogeochemical and physical environmental factors. Synergistic interactions can occur when the combined effects of stressors exceed their individual effects. The Red Sea, characterized by strong gradients in temperature, salinity, and nutrients along the latitudinal axis provides a unique opportunity to study ecological responses over a range of these environmental variables. Using multiple linear regression models integrating in situ, satellite and oceanographic data, we investigated the response of coral reef taxa to local stressors and recent climate variability. Taxa and functional groups responded to a combination of climate (temperature, salinity, air-sea heat fluxes, irradiance, wind speed), fishing pressure and biogeochemical (chlorophyll a and nutrients - phosphate, nitrate, nitrite) factors. The regression model for each species showed interactive effects of climate, fishing pressure and nutrient variables. The nature of the effects (antagonistic or synergistic) was dependent on the species and stressor pair. Variables consistently associated with the highest number of synergistic interactions included heat flux terms, temperature, and wind speed followed by fishing pressure. Hard corals and coralline algae abundance were sensitive to changing environmental conditions where synergistic interactions decreased their percentage cover. These synergistic interactions suggest that the negative effects of fishing pressure and eutrophication may exacerbate the impact of climate change on corals. A high number of interactions were also recorded for algae, however for this group, synergistic interactions increased algal abundance. This study is unique in applying regression analysis to multiple environmental variables simultaneously to understand stressor interactions in the field. The observed responses have important implications for understanding climate change impacts on marine ecosystems and whether managing local stressors, such as nutrient enrichment and fishing activities, may help mitigate global drivers of change.


Assuntos
Antozoários , Recifes de Corais , Animais , Clorofila A , Mudança Climática , Ecossistema , Oceano Índico
16.
J Hum Evol ; 126: 91-105, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30583846

RESUMO

The newly described partial skeleton of Paranthropus boisei KNM-ER 47000 as well as the FwJj14E Ileret footprints provide new evidence on the paleobiology and diversity of hominins from the Okote Member of the Koobi Fora Formation at East Turkana about 1.5 Ma. To better understand the ecological context of the Okote hominins, it is necessary to broaden the geographical focus of the analysis to include the entire Omo-Turkana ecosystem, and the temporal focus to encompass the early Pleistocene. Previous work has shown that important changes in the regional vegetation occurred after 2 Ma, and that there was a peak in mammalian turnover and diversity close to 1.8 Ma. This peak in diversity included the Hominini, with the species P. boisei, Homo habilis, Homo rudolfensis, and Homo erectus co-occurring at around 1.8 Ma. There is considerable debate about whether H. habilis and H. rudolfensis indeed constitute separate species, but even if we consider them both as H. habilis sensu lato, the co-occurrence of three hominin species at any one time and place is rather unusually high diversity for hominin standards (even if not so for other mammalian groups such as suids, bovids, or cercopithecids). Here we use mammalian faunal abundance data to place confidence intervals on first and last appearances of hominin species in the early Pleistocene of the Omo-Turkana Basin, and use these estimates to discuss hominin diversity in the Okote Member. We suggest that in the early Pleistocene a wide range of depositional environments and vegetation types, along with a high frequency of volcanism, likely maintained high levels of environmental variability both in time and space across the Omo-Turkana region, and provided ecological opportunities for the coexistence of at least three hominin species alongside a diverse mammalian fauna.


Assuntos
Biodiversidade , Evolução Biológica , Meio Ambiente , Hominidae , Animais , Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Quênia , Paleontologia
17.
J Hum Evol ; 130: 1-20, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31010537

RESUMO

Most authors recognize six baboon species: hamadryas (Papio hamadryas), Guinea (Papio papio), olive (Papio anubis), yellow (Papio cynocephalus), chacma (Papio ursinus), and Kinda (Papio kindae). However, there is still debate regarding the taxonomic status, phylogenetic relationships, and the amount of gene flow occurring between species. Here, we present ongoing research on baboon morphological diversity in Gorongosa National Park (GNP), located in central Mozambique, south of the Zambezi River, at the southern end of the East African Rift System. The park exhibits outstanding ecological diversity and hosts more than 200 baboon troops. Gorongosa National Park baboons have previously been classified as chacma baboons (P. ursinus). In accordance with this, two mtDNA samples from the park have been placed in the same mtDNA clade as the northern chacma baboons. However, GNP baboons exhibit morphological features common in yellow baboons (e.g., yellow fur color), suggesting that parapatric gene flow between chacma and yellow baboons might have occurred in the past or could be ongoing. We investigated the phenostructure of the Gorongosa baboons using two approaches: 1) description of external phenotypic features, such as coloration and body size, and 2) 3D geometric morphometric analysis of 43 craniofacial landmarks on 11 specimens from Gorongosa compared to a pan-African sample of 352 baboons. The results show that Gorongosa baboons exhibit a mosaic of features shared with southern P. cynocephalus and P. ursinus griseipes. The GNP baboon phenotype fits within a geographic clinal pattern of replacing allotaxa. We put forward the hypothesis of either past and/or ongoing hybridization between the gray-footed chacma and southern yellow baboons in Gorongosa or an isolation-by-distance scenario in which the GNP baboons are geographically and morphologically intermediate. These two scenarios are not mutually exclusive. We highlight the potential of baboons as a useful model to understand speciation and hybridization in early human evolution.


Assuntos
Face/anatomia & histologia , Papio cynocephalus/anatomia & histologia , Papio ursinus/anatomia & histologia , Crânio/anatomia & histologia , Animais , Feminino , Fluxo Gênico , Masculino , Moçambique , Papio cynocephalus/classificação , Papio cynocephalus/genética , Papio ursinus/classificação , Papio ursinus/genética , Fenótipo , Filogenia
18.
Evol Anthropol ; 27(6): 285-296, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30290031

RESUMO

Property is a key feature of modern human society; however, identifying the origin of this multifaceted behavior poses a formidable challenge. Here, we explore the methodologies for researching the origin of property. We discuss how an interdisciplinary approach can shed light on how our human ancestors shifted behaviorally from possessing an object to having exclusive property control over it. Possession occurs when social group members only respect an individual's claim to have exclusive access to an object when the individual has physical control over the object. Property occurs when an individual can claim exclusive access to an object, without challenge, regardless of whether the object is in their physical control or not. Researchers across different disciplines have asked what, if anything, distinguishes human property behavior from the behavior of other animals? Further, when and how did this behavior evolve in our lineage? Due to the considerable methodological challenges posed by researching this topic, few studies have been able to directly address these questions. In this review, we explore the challenges involved in defining property and possession and suggest a two-step approach to interdisciplinary definitions. Next, we evaluate four core approaches to the study of property behavior: evolutionary game theory, ethology, comparative cognition, and developmental psychology. Finally, we propose an empirical study, using an ethological approach to test the presence of property and possessive behavior in a natural setting, using our closest living relative, the chimpanzee (Pan troglodytes). Overall, we argue that this field of research is at a turning point, where the novel integration of various methods may provide an explanation to the origin of property.


Assuntos
Comportamento Animal , Evolução Biológica , Pan troglodytes/fisiologia , Animais , Antropologia Física , Etologia , Modelos Biológicos , Propriedade
19.
J Sci Food Agric ; 97(11): 3603-3612, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28102029

RESUMO

BACKGROUND: The aim of this study was to identify biochemical markers to predict internal browning disorders (IBD) in 'Rocha' pear. Fruits from five orchards were stored for 45 days under cold air followed by 100 days in browning-inducing controlled atmosphere (CA) conditions (1 kPa O2 + 10 kPa CO2 ). RESULTS: Relationships between concentrations of ethanol (EtOH), acetaldehyde (AcDH) and ascorbic acid (AA), activities of peroxidase (POX) and polyphenoloxidase (PPO) and IBD incidence were established. The partial least square (PLS) model using the most promising markers, EtOH and AcDH, explained 89% of the variance in IBD incidence, whereas the univariate models based on the same markers explained between 89 and 94%. In contrast, the models based on AA levels and AA depletion rate only explained 57 and 82% of the variance in IBD incidence respectively. Model validation confirmed the robustness of EtOH for the prediction (R2 = 0.91, RMSE = 11.1) and allowed proposing a threshold level of 30 µL EtOH L-1 above which IBD may occur. Using this threshold value, the storage time limit associated with the occurrence of the first IBD symptoms was predicted with an acceptable RMSE of 9 days. CONCLUSION: This work clearly identifies biochemical IBD markers for 'Rocha' pear and shows that dynamic changes in ethanol concentration during the beginning of storage may be used to predict IBD development. Therefore the results presented herein represent a major step forward in the prediction of IBD in 'Rocha' pear. © 2017 Society of Chemical Industry.


Assuntos
Catecol Oxidase/análise , Frutas/química , Oxirredutases/análise , Proteínas de Plantas/análise , Pyrus/química , Biomarcadores/análise , Dióxido de Carbono/análise , Cor , Conservação de Alimentos , Armazenamento de Alimentos
20.
Ecotoxicology ; 25(4): 664-76, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26911481

RESUMO

The chronic exposure of benthic organisms to metals in sediments can lead to the development of tolerance mechanisms, thus diminishing their responsiveness. This study aims to evaluate the accumulation profiles of V, Cr, Co, Ni, As, Cd, Pb and Hg and antioxidant system responses of two benthic organisms (Cerastoderma edule, Bivalvia; Nephtys hombergii, Polychaeta). This approach will provide clarifications about the ability of each species to signalise metal contamination. Organisms of both species were collected at the Tagus estuary, in two sites with distinct contamination degrees (ALC, slightly contaminated; BAR, highly contaminated). Accordingly, C. edule accumulated higher concentrations of As, Pb and Hg at BAR compared to ALC. However, antioxidant responses of C. edule were almost unaltered at BAR and no peroxidative damage occurred, suggesting adjustment mechanisms to the presence of metals. In contrast, N. hombergii showed a minor propensity to metal accumulation, only signalising spatial differences for As and Pb and accumulating lower concentrations of metals than C. edule. The differences in metal accumulation observed between species might be due to their distinctive foraging behaviour and/or the ability of N. hombergii to minimise the metal uptake. Despite that, the accumulation of As and Pb was on the basis of the polychaete antioxidant defences inhibition at BAR, including CAT, SOD, GR and GPx. The integrated biomarker response index (IBRv2) confirmed that N. hombergii was more affected by metal exposure than C. edule. In the light of current findings, in field-based studies, the information of C. edule as a bioindicator should be complemented by that provided by another benthic species, since tolerance mechanisms to metals can hinder a correct diagnosis of sediment contamination and of the system's health. Overall, the present study contributed to improve the lack of fundamental knowledge of two widespread and common estuarine species, providing insights of the metal accumulation profiles under a scenario of chronic contamination. Finally, this work provided useful information that can be applied in the interpretation of future environmental monitoring studies.


Assuntos
Cardiidae/fisiologia , Monitoramento Ambiental , Metais/toxicidade , Estresse Oxidativo , Poliquetos/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Cardiidae/metabolismo , Metalotioneína/metabolismo , Metais/metabolismo , Poliquetos/metabolismo , Poluentes Químicos da Água/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA