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1.
Am Nat ; 202(5): 699-720, 2023 11.
Article in English | MEDLINE | ID: mdl-37963119

ABSTRACT

AbstractDifferences among hummingbird species in bill length and shape have rightly been viewed as adaptive in relation to the morphology of the flowers they visit for nectar. In this study we examine functional variation in a behaviorally related but neglected feature: hummingbird feet. We gathered records of hummingbirds clinging by their feet to feed legitimately as pollinators or illegitimately as nectar robbers-"unorthodox" feeding behaviors. We measured key features of bills and feet for 220 species of hummingbirds and compared the 66 known "clinger" species (covering virtually the entire scope of hummingbird body size) with the 144 presumed "non-clinger" species. Once the effects of phylogenetic signal, body size, and elevation above sea level are accounted for statistically, hummingbirds display a surprising but functionally interpretable negative correlation. Clingers with short bills and long hallux (hind-toe) claws have evolved-independently-more than 20 times and in every major clade. Their biomechanically enhanced feet allow them to save energy by clinging to feed legitimately on short-corolla flowers and by stealing nectar from long-corolla flowers. In contrast, long-billed species have shorter hallux claws, as plant species with long-corolla flowers enforce hovering to feed, simply by the way they present their flowers.


Subject(s)
Flowers , Plant Nectar , Animals , Phylogeny , Flowers/anatomy & histology , Birds/anatomy & histology , Feeding Behavior , Pollination
2.
Nature ; 622(7983): 537-544, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37758942

ABSTRACT

Climate's effect on global biodiversity is typically viewed through the lens of temperature, humidity and resulting ecosystem productivity1-6. However, it is not known whether biodiversity depends solely on these climate conditions, or whether the size and fragmentation of these climates are also crucial. Here we shift the common perspective in global biodiversity studies, transitioning from geographic space to a climate-defined multidimensional space. Our findings suggest that larger and more isolated climate conditions tend to harbour higher diversity and species turnover among terrestrial tetrapods, encompassing more than 30,000 species. By considering both the characteristics of climate itself and its geographic attributes, we can explain almost 90% of the variation in global species richness. Half of the explanatory power (45%) may be attributed either to climate itself or to the geography of climate, suggesting a nuanced interplay between them. Our work evolves the conventional idea that larger climate regions, such as the tropics, host more species primarily because of their size7,8. Instead, we underscore the integral roles of both the geographic extent and degree of isolation of climates. This refined understanding presents a more intricate picture of biodiversity distribution, which can guide our approach to biodiversity conservation in an ever-changing world.


Subject(s)
Biodiversity , Climate , Geography , Animals , Conservation of Natural Resources/methods , Geographic Mapping , Humidity , Temperature , Tropical Climate
3.
J Clin Periodontol ; 50(7): 942-951, 2023 07.
Article in English | MEDLINE | ID: mdl-36935103

ABSTRACT

AIM: To compare the salivary proteomic profile of periodontitis-affected (PA) parents and their offspring to periodontally healthy (PH) dyads in the pursuit of possible biomarkers for early diagnosis of this disease. MATERIALS AND METHODS: Unstimulated saliva samples collected from 17 pairs of PA or PH individuals and their children were submitted to mass spectrometric analyses followed by proteomic analyses. Primary PA fibroblasts were triggered towards having an inflammatory response, and an immunoenzymatic assay of its supernatant was performed to validate the obtained data. RESULTS: ANXA1, KRT4, GSTP1, HPX, A2M and KRT13 were lower in PA parents and their children, and IGHG1, CSTB, KRT9, SMR3B, IGHG4 and SERPINA1 were higher. ANXA1 presented the highest fold change, 7.1 times less produced in children of PA parents, and was selected as a potential biomarker for periodontitis. The in vitro assay also showed lower ANXA1 production by cells of PA patients. CONCLUSION: Before any clinical sign of periodontal loss, descendants of PA patients have an altered proteomic profile compared to PH individuals, presenting a lower abundance of ANXA1. This protein is suggested as a potential biomarker for periodontitis.


Subject(s)
Annexin A1 , Periodontitis , Child , Humans , Annexin A1/analysis , Annexin A1/metabolism , Biomarkers/metabolism , Periodontitis/diagnosis , Periodontitis/metabolism , Proteomics , Saliva/chemistry
4.
Proc Natl Acad Sci U S A ; 120(2): e2211974120, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36595684

ABSTRACT

Landscape dynamics are widely thought to govern the tempo and mode of continental radiations, yet the effects of river network rearrangements on dispersal and lineage diversification remain poorly understood. We integrated an unprecedented occurrence dataset of 4,967 species with a newly compiled, time-calibrated phylogeny of South American freshwater fishes-the most species-rich continental vertebrate fauna on Earth-to track the evolutionary processes associated with hydrogeographic events over 100 Ma. Net lineage diversification was heterogeneous through time, across space, and among clades. Five abrupt shifts in net diversification rates occurred during the Paleogene and Miocene (between 30 and 7 Ma) in association with major landscape evolution events. Net diversification accelerated from the Miocene to the Recent (c. 20 to 0 Ma), with Western Amazonia having the highest rates of in situ diversification, which led to it being an important source of species dispersing to other regions. All regional biotic interchanges were associated with documented hydrogeographic events and the formation of biogeographic corridors, including the Early Miocene (c. 23 to 16 Ma) uplift of the Serra do Mar and Serra da Mantiqueira and the Late Miocene (c. 10 Ma) uplift of the Northern Andes and associated formation of the modern transcontinental Amazon River. The combination of high diversification rates and extensive biotic interchange associated with Western Amazonia yielded its extraordinary contemporary richness and phylogenetic endemism. Our results support the hypothesis that landscape dynamics, which shaped the history of drainage basin connections, strongly affected the assembly and diversification of basin-wide fish faunas.


Subject(s)
Fishes , Fresh Water , Animals , Phylogeny , Fishes/genetics , Rivers , South America , Biodiversity , Phylogeography
5.
J Periodontal Res ; 57(6): 1116-1126, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36050890

ABSTRACT

OBJECTIVE: This study aimed to investigate the influence of smoking on clinical, microbiological and immunological parameters in young adult with stage III-IV Grade C periodontitis after full-mouth ultrasonic debridement (FMUD) associated with Amoxicillin and Metronidazole (AMX + MTZ), comparing smokers (PerioC-Y-Smk) with non-smokers (PerioC-Y-NSmk). MATERIALS AND METHODS: Fifteen PerioC-Y-NSmk and 14 PerioC-Y-Smk patients underwent FMUD associated with AMX + MTZ for 10 days. All parameters were collected at baseline and 3 and 6 months after treatment. Plaque index (PI), bleeding on probing (BoP), probing depth (PD), clinical attachment level (CAL)- the primary variable-, and gingival recession (GR) were clinically assessed. The impact of PI on CAL change at 6-month was verified by a regression analysis. Samples of the subgingival biofilm was collected for detection of levels of Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis (P.gingivalis), Tannerella forsythia (T. forsythia), and Fusobacterium nucleatum ssp (F. nucleatum), and were analyzed by real-time qPCR; gingival crevicular fluid was collected for detection of levels of interleukin (IL)-1ß, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ, which were analyzed using an enzyme immunoassay. RESULTS: PerioC-Y-Smk had significantly higher PI, BOP, and GR at baseline compared to non-smokers (p < .05). PerioC-Y-Smk presented higher PD, CAL, and GR at 3 and 6 months (p < .05) compared with PerioC-Y-NSmk in the same periods; PI negatively affected CAL gain in PerioC-Y-NSmk at 6-month follow-up (p = .052) and did not impact on clinical response in PerioC-Y-Smk (p = .882). Lower levels of IFN-γ, IL1-ß, and IL-4 were observed at 3 months in the PerioC-Y-NSmk (p < .05) compared with PerioC-Y-Smk. Lower proportions of P. gingivalis were observed in PerioC-Y-NSmk at baseline and at 3 months (p < .05) and lower proportions of F. nucleatum were observed at 6 months, in the PerioC-Y-NSmk (p < .05). CONCLUSIONS: PerioC-Y-Smk presents an unfavorable clinical, microbiological, and immunological response after 3 and 6 months after FMUD associated with AMX + MTZ. CLINICAL RELEVANCE: Smoking worsens periodontal condition of young treated adults presenting stage III/IV Grade C periodontitis.


Subject(s)
Interleukin-4 , Periodontitis , Humans , Young Adult , Periodontitis/drug therapy , Gingival Crevicular Fluid , Amoxicillin/therapeutic use , Metronidazole/therapeutic use , Aggregatibacter actinomycetemcomitans , Porphyromonas gingivalis , Smoking/adverse effects , Follow-Up Studies
6.
Sci Total Environ ; 802: 149867, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-34469861

ABSTRACT

The present study performed geochemical fractioning of major and minor elements in a cross-shelf gradient of the Abrolhos Bank, where the largest and most diverse coral reefs in the South Atlantic are concentrated. The fractioning was performed using sequential extractions to determine the degree of availability and toxicity of the elements. The mobility pattern of the elements investigated were in the following order: Ca > Mn > Pb > Cr > Zn > Fe > V > Cu > Ba>Al > Ni > Ti. For elements, such as (Ti, Ni, Al, Ba, Cu, V, Fe, Zn, Cr, Pb), the highest concentrations were in the residual phase at some sampling sites. As established by Environment Canada (Threshold Effect Level - TEL and Probable Effect Level - PEL), Ba, Cr, and Ni produced values higher than the limits, associated with higher concentrations of other elements. In addition, significant proportions of these elements were found in mobile phases in the same sites. Thus, more rigorous measures are critical to avoid alarming levels of chronic environmental pollution inside and outside protected areas of the region. To enhance the sustainability of the region, more effective enforcement is crucial to prevent anthropic contamination that may threaten its biodiversity. The results provide the baseline for future studies regarding the potential impacts of the breach of the tailings dam in the region of Mariana, Minas Gerais.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Environmental Monitoring , Geologic Sediments , Metals, Heavy/analysis , Risk Assessment , Water Pollutants, Chemical/analysis
7.
Proc Biol Sci ; 288(1965): 20211879, 2021 12 22.
Article in English | MEDLINE | ID: mdl-34905709

ABSTRACT

Insular biodiversity is expected to be regulated differently than continental biota, but their determinants remain to be quantified at a global scale. We evaluated the importance of physical, environmental and historical factors on mammal richness and endemism across 5592 islands worldwide. We fitted generalized linear and mixed models to accommodate variation among biogeographic realms and performed analyses separately for bats and non-volants. Richness on islands ranged from one to 234 species, with up to 177 single island endemics. Diversity patterns were most consistently influenced by the islands' physical characteristics. Area positively affected mammal diversity, in particular the number of non-volant endemics. Island isolation, both current and past, was associated with lower richness but greater endemism. Flight capacity modified the relative importance of past versus current isolation, with bats responding more strongly to current and non-volant mammals to past isolation. Biodiversity relationships with environmental factors were idiosyncratic, with a tendency for greater effects sizes with endemism than richness. The historical climatic change was positively associated with endemism. In line with theory, we found that area and isolation were among the strongest drivers of mammalian biodiversity. Our results support the importance of past conditions on current patterns, particularly of non-volant species.


Subject(s)
Biodiversity , Climate , Animals , Geography , Islands , Mammals
8.
J Periodontal Res ; 56(6): 1213-1222, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34541683

ABSTRACT

BACKGROUND: This study was conducted to evaluate the clinical, immunologic, and patient-centered outcomes of enamel matrix protein derivative (EMD) on excisional wounds in palatal mucosa. MATERIALS: Forty-four patients in need of ridge preservation were randomly allocated into two groups: control group (n = 22): open palatal wound after free gingival graft (FGG) harvest and EMD group (n = 22): open palatal wound after FGG harvest that received 0.3 ml of EMD. Clinical and patient-centered parameters were analyzed for 3 months post-treatment. Wound fluid levels of inflammatory markers were assessed 3 and 7 days postoperatively. RESULTS: No significant inter-group difference was observed in remaining wound area and re-epithelialization. EMD and control groups achieved wound closure and re-epithelialization 30 days postoperatively (p < .001), without inter-group differences. Similarly, number of analgesics and Oral Health Impact Profile scores did not present significant inter-group differences (p > .05). EMD appeared to selectively modulate wound fluid levels of monocyte chemoattractant protein-1, macrophage inflammatory protein-1α, matrix metallopeptidase 9, and tissue inhibitor of metalloproteinases-2. CONCLUSION: Within the limits of the present study, it can be concluded that EMD application to excisional palatal wounds using the investigated protocol does not provide clinical healing benefits, despite an apparent modulation of selected inflammatory markers.


Subject(s)
Dental Enamel Proteins , Gingival Recession , Dental Enamel , Humans , Mucous Membrane , Palate/surgery , Wound Healing
9.
Glob Ecol Biogeogr ; 30(9): 1899-1908, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34588924

ABSTRACT

AIM: We aimed to dissect the spatial variation of the direct and indirect effects of climate and productivity on global species richness of terrestrial tetrapods. LOCATION: Global. TIME PERIOD: Present. MAJOR TAXA STUDIED: Terrestrial tetrapods. METHODS: We used a geographically weighted path analysis to estimate and map the direct and indirect effects of temperature, precipitation and primary productivity on species richness of terrestrial tetrapods across the globe. RESULTS: We found that all relationships shift in magnitude, and even in direction, among taxonomic groups, geographical regions and connecting paths. Direct effects of temperature and precipitation are generally stronger than both indirect effects mediated by productivity and direct effects of productivity. MAIN CONCLUSIONS: Richness gradients seem to be driven primarily by effects of climate on organismal physiological limits and metabolic rates rather than by the amount of productive energy. Reptiles have the most distinct relationships across tetrapods, with a clear latitudinal pattern in the importance of temperature versus water.

10.
PLoS Biol ; 19(7): e3001340, 2021 07.
Article in English | MEDLINE | ID: mdl-34252071

ABSTRACT

Understanding the origins of biodiversity has been an aspiration since the days of early naturalists. The immense complexity of ecological, evolutionary, and spatial processes, however, has made this goal elusive to this day. Computer models serve progress in many scientific fields, but in the fields of macroecology and macroevolution, eco-evolutionary models are comparatively less developed. We present a general, spatially explicit, eco-evolutionary engine with a modular implementation that enables the modeling of multiple macroecological and macroevolutionary processes and feedbacks across representative spatiotemporally dynamic landscapes. Modeled processes can include species' abiotic tolerances, biotic interactions, dispersal, speciation, and evolution of ecological traits. Commonly observed biodiversity patterns, such as α, ß, and γ diversity, species ranges, ecological traits, and phylogenies, emerge as simulations proceed. As an illustration, we examine alternative hypotheses expected to have shaped the latitudinal diversity gradient (LDG) during the Earth's Cenozoic era. Our exploratory simulations simultaneously produce multiple realistic biodiversity patterns, such as the LDG, current species richness, and range size frequencies, as well as phylogenetic metrics. The model engine is open source and available as an R package, enabling future exploration of various landscapes and biological processes, while outputs can be linked with a variety of empirical biodiversity patterns. This work represents a key toward a numeric, interdisciplinary, and mechanistic understanding of the physical and biological processes that shape Earth's biodiversity.


Subject(s)
Biological Evolution , Computer Simulation , Earth, Planet , Biodiversity , Ecology , Empirical Research , Genetic Speciation
11.
Sci Total Environ ; 756: 143697, 2021 Feb 20.
Article in English | MEDLINE | ID: mdl-33307494

ABSTRACT

The rupture of Fundão Dam is considered one of the largest environmental disasters in Brazilian history and one of the largest in the world involving tailings dams. The present study analyzed the changes in metal concentrations in the dissolved, suspended particulate matter (SPM) and sediment in the period just after (15 days) and six months after the dam rupture, together with the biological and cytogenotoxic effects, from the collapse site until the Doce River mouth in the Atlantic Ocean. After the dam rupture, the tailings were mainly transported as SPM. After six months, with the deposition, there was a decrease in metal concentrations in dissolved and SPM and increased levels were observed in the sediment. Cr, Ni, Cd and Hg levels in sediment were higher than the threshold effects level (TEL/NOAA), especially six months after the dam rupture. The water induced immediate negative biological effects at different levels of the trophic chain, together with Al, Fe, Mn and Zn accumulation in fish muscle. Both water and sediment also showed cytotoxic, genotoxic and mutagenic effects. These data demonstrate the importance of long-term monitoring with abiotic and biotic parameters to clarify the impacts of mining tailings and can help to direct future monitoring programs.


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Animals , Atlantic Ocean , Brazil , Environmental Monitoring , Metals, Heavy/analysis , Mining , Propanolamines , Rivers , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity
12.
Oral Dis ; 27(5): 1325-1333, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33012042

ABSTRACT

BACKGROUND: Periodontal disease and diabetes mellitus (DM) are highly prevalent and interrelated diseases, resulting in altered host response microbiota. Thus, this study aimed to evaluate the impact of DM on local levels of lipopolysaccharide (LPS) and lipoteichoic acid (LTA) and their relationship with cytokines and matrix metalloproteinases' (MMPs) profile. METHODS: This case-control study included diabetic (n = 15) and non-diabetic (n = 15) subjects presenting Stage 3-4, Grade C, Periodontitis. Gingival crevicular fluid (GCF) was collected, and LPS and LTA levels were analyzed by enzyme-linked immunosorbent assay (ELISA), while IFN-γ, IL-10, IL-17, IL-1ß, IL-4, MMP-2, and MMP-9 were measured by LUMINEX/MAGpix. Mann-Whitney and Spearman's correlation tests were used to compared and to correlate variables (p < 0.05). RESULTS: Higher levels of LTA, LPS, IL-10, IL-1ß, and MMP-2 (p < 0.05) and lower levels of IL-17 were found in the DM group (p < 0.05). Non-diabetic subjects presented higher LPS, IFN-γ, IL-17, and MMP-2 levels and lower IL-10 concentration (p < 0.05). No significant correlation was seen between LPS and cytokine profile in non-diabetic. Local levels of LTA were positively correlated with IL-17 and MMP-2 and negatively with IL-10. CONCLUSION: LTA and LPS drove the inflammatory profile through the modulation of cytokines and MMPs in a different manner in DM and non-diabetic subjects.


Subject(s)
Diabetes Mellitus , Lipopolysaccharides , Case-Control Studies , Cytokines/analysis , Endotoxins , Gingival Crevicular Fluid/chemistry , Teichoic Acids
13.
iScience ; 23(11): 101693, 2020 Nov 20.
Article in English | MEDLINE | ID: mdl-33163945

ABSTRACT

Homo sapiens is the only species alive able to take advantage of its cognitive abilities to inhabit almost all environments on Earth. Humans are able to culturally construct, rather than biologically inherit, their occupied climatic niche to a degree unparalleled within the animal kingdom. Precisely, when hominins acquired such an ability remains unknown, and scholars disagree on the extent to which our ancestors shared this same ability. Here, we settle this issue using fine-grained paleoclimatic data, extensive archaeological data, and phylogenetic comparative methods. Our results indicate that whereas early hominins were forced to live under physiologically suitable climatic conditions, with the emergence of H. heidelbergensis, the Homo climatic niche expanded beyond its natural limits, despite progressive harshening in global climates. This indicates that technological innovations providing effective exploitation of cold and seasonal habitats predated the emergence of Homo sapiens.

14.
Ecotoxicol Environ Saf ; 195: 110449, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-32220791

ABSTRACT

Environmental pollutants affect fish species differently because their routes of exposure make them more critical to a specific group regarding foraging habits or food preferences. However, the association between local problems and environmental conditions makes a particular species more suitable for use in monitoring programs. Thus, this study compared muscle accumulation of metals (Al, Ba, Cr, Cu, Fe, Mn, Ti and Zn) and toxicogenetic damage to three neotropical species from the Itapemirim River Basin (Brazil) with distinct foraging habits and feeding preferences: Geophagus brasiliensis (benthopelagic - omnivorous); Harttia sp. (benthic - detritivorous); and Leporinus copellandii (pelagic - omnivorous). There was seasonal influence on muscle metal concentrations: Ba and Mn concentrations in G. brasiliensis, Cr in Harttia sp. and Zn, Al and Fe in L. copellandii increased during the rainy season. G. brasiliensis was the most sensitive species, since it had a statistically higher prevalence of erythrocytic nuclear abnormalities, which was influenced by seasonality. This result might be an effect of its benthopelagic habits, which favors contact with a larger group of contaminants due to its interaction with both water column and sediment. The present study showed the differential sensitivity of fish species and that the combination of chemical analysis of pollutants with evaluation of toxicogenetic responses helps to choose the best species for field studies.


Subject(s)
Fishes/metabolism , Metals/metabolism , Metals/toxicity , Water Pollutants, Chemical/metabolism , Water Pollutants, Chemical/toxicity , Animals , Brazil , Cichlids/metabolism , DNA Damage , Environmental Monitoring , Feeding Behavior , Fishes/physiology , Muscles/metabolism , Rivers
15.
Sci Total Environ ; 705: 135914, 2020 Feb 25.
Article in English | MEDLINE | ID: mdl-31838417

ABSTRACT

On 25 January 2019, Córrego do Feijão's tailing dam at Brumadinho city (Minas Gerais, Brazil) breached, leaving over 250 people dead. At least 12 million cubic meters of ore tailing were spread into Paraopeba River and the surrounding area. To evaluate the short-term impacts of the Brumadinho dam rupture on the environment, we performed biogeochemical, microbiological and ecotoxicological analyses across 464 km of the Paraopeba River in the week following the disaster (1 February 2019) and four months latter (27-29 May 2019). Immediately after the disaster, the water turbidity was 3000 NTU, 30 times greater than the standard recommended by the Brazilian Resolution for Water Quality (CONAMA 357). Up to a 60-fold increase in iron tolerant microbial colony forming unities was observed up to 115 km downstream of the dam failure in May 2019 (compared with February 2019), suggesting changes in microbial metabolic profiles. In the second sampling (May 2019), the ecotoxicological analyses indicate higher zebrafish embryo mortality (up to ~85% embryo mortality) rates in Retiro Baixo (304 km from dam failure location). However, increased zebrafish mortality in Retiro Baixo and Três Marias reservoirs may not be related exclusively to the dam failure. The causal nexus of mortality may be associated with other factors (e.g. local sewage pollution). Our study suggests that independent monitoring programs are needed to quantify the extent of potential impacts caused by the anthropogenic use of the river and to promote the recovery of the impacted area.

16.
Sci. Total Environ. ; 705: 135914, 2020.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17426

ABSTRACT

On 25 January 2019, Córrego do Feijão's tailing dam at Brumadinho city (Minas Gerais, Brazil) breached, leaving over 250 people dead. At least 12 million cubic meters of ore tailing were spread into Paraopeba River and the surrounding area. To evaluate the short-term impacts of the Brumadinho dam rupture on the environment, we performed biogeochemical, microbiological and ecotoxicological analyses across 464 km of the Paraopeba River in the week following the disaster (1 February 2019) and four months latter (27–29 May 2019). Immediately after the disaster, the water turbidity was 3000 NTU, 30 times greater than the standard recommended by the Brazilian Resolution for Water Quality (CONAMA 357). Up to a 60-fold increase in iron tolerant microbial colony forming unities was observed up to 115 km downstream of the dam failure in May 2019 (compared with February 2019), suggesting changes in microbial metabolic profiles. In the second sampling (May 2019), the ecotoxicological analyses indicate higher zebrafish embryo mortality (up to ~85% embryo mortality) rates in Retiro Baixo (304 km from dam failure location). However, increased zebrafish mortality in Retiro Baixo and Três Marias reservoirs may not be related exclusively to the dam failure. The causal nexus of mortality may be associated with other factors (e.g. local sewage pollution). Our study suggests that independent monitoring programs are needed to quantify the extent of potential impacts caused by the anthropogenic use of the river and to promote the recovery of the impacted area.

18.
PLoS One ; 14(11): e0225128, 2019.
Article in English | MEDLINE | ID: mdl-31774852

ABSTRACT

This study uses species distribution modeling and physiological and functional traits to predict the impacts of climate change on native freshwater fish in the Murray-Darling Basin, Australia. We modelled future changes in taxonomic and functional diversity in 2050 and 2080 for two scenarios of carbon emissions, identifying areas of great interest for conservation. Climatic-environmental variables were used to model the range of 23 species of native fish under each scenario. The consensus model, followed by the physiological filter of lethal temperature was retained for interpretation. Our study predicts a severe negative impact of climate change on both taxonomic and functional components of ichthyofauna of the Murray-Darling Basin. There was a predicted marked contraction of species ranges under both scenarios. The predictions showed loss of climatically suitable areas, species and functional characters. There was a decrease in areas with high values of functional richness, dispersion and uniqueness. Some traits are predicted to be extirpated, especially in the most pessimistic scenario. The climatic refuges for fish fauna are predicted to be in the southern portion of the basin, in the upper Murray catchment. Incorporating future predictions about the distribution of ichthyofauna in conservation management planning will enhance resilience to climate change.


Subject(s)
Fishes/classification , Fishes/physiology , Animals , Australia , Biodiversity , Climate Change , Conservation of Natural Resources , Demography , Models, Biological , Reproduction
19.
Ecol Evol ; 9(19): 11136-11144, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31641461

ABSTRACT

Ecological Niche Models (ENMs) have different performances in predicting potential geographic distributions. Here we meta-analyzed the likely effects of climate change on the potential geographic distribution of 1,205 bird species from the Neotropical region, modeled using eight ENMs and three Atmosphere-Ocean General Circulation Models (AOGCM). We considered the variability in ENMs performance to estimate a weighted mean difference between potential geographic distributions for baseline and future climates. On average, potential future ranges were projected to be from 25.7% to 44.5% smaller than current potential ranges across species. However, we found that 0.2% to 18.3% of the total variance in range shifts occurred "within species" (i.e., owing to the use of different modeling techniques and climate models) and 81.7% to 99.8% remained between species (i.e., it could be explained by ecological correlates). Using meta-analytical techniques akin to regression, we also showed that potential range shifts are barely predicted by bird biological traits. We demonstrated that one can combine and reduce species-specific effects with high uncertainty in ENMs and also explore potential causes of climate change effect on species using meta-analytical tools. We also highlight that the search for powerful correlates of climate change-induced range shifts can be a promising line of investigation.

20.
Biol Lett ; 15(10): 20190481, 2019 10 31.
Article in English | MEDLINE | ID: mdl-31594495

ABSTRACT

According to the island rule, small-bodied vertebrates will tend to evolve larger body size on islands, whereas the opposite happens to large-bodied species. This controversial pattern has been studied at the macroecological and biogeographical scales, but new developments in quantitative evolutionary genetics now allow studying the island rule from a mechanistic perspective. Here, we develop a simulation approach based on an individual-based model to model body size change on islands as a progressive adaptation to a moving optimum, determined by density-dependent population dynamics. We applied the model to evaluate body size differentiation in the pigmy extinct hominin Homo floresiensis, showing that dwarfing may have occurred in only about 360 generations (95% CI ranging from 150 to 675 generations). This result agrees with reports suggesting rapid dwarfing of large mammals on islands, as well as with the recent discovery that small-sized hominins lived in Flores as early as 700 kyr ago. Our simulations illustrate the power of analysing ecological and evolutionary patterns from an explicit quantitative genetics perspective.


Subject(s)
Hominidae , Animals , Biological Evolution , Body Size , Fossils , Indonesia , Islands , Mammals
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