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1.
J Hum Evol ; 163: 103125, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34954399

RESUMO

We undertake a comparative mammalian zoogeographic analysis with the aim of revealing the extent to which the Dmanisi Early Pleistocene large mammal assemblage resembles, at the genus level, African, Arabian, and Eurasian localities of similar age. The inclusion of Old World Pliocene and Pleistocene mammalian faunas provides us with insights into the provincial origins of specific mammalian taxa and permits us to assess the relative affiliation of the Dmanisi mammalian faunas to other faunas in the Old World. Our analysis also allows us to consider hypotheses about the timing and direction of zoogeographic connections between western Eurasia and Africa during the Early Pleistocene. We utilize multiple zoogeographic analytical tools as a cross-comparison of Dmanisi with 42 other Eurasian and African mammalian-bearing localities between 2.7 and 0.7 Ma. Overall, we find that Dmanisi compares most closely with a subgroup of Greek, Italian, and Spanish localities that are slightly younger than Dmanisi itself. This could suggest a progressive dispersal from East to West of the large mammal communities during the late Early Pleistocene and the first occurrence at Dmanisi, and then later in Western Europe, of some taxa such as Stephanorhinus ex gr. etruscus-hundsheimensis, Equus altidens, Bison georgicus, Soergelia minor, Megantereon whitei, Canis borjgali, Canis (Xenocyon) lycaonoides. Dmanisi's habitats included drier areas, probably of open wooded savannah and grassland and by mountainous to semiarid rocky terrain. There is evidence that Dmanisi records short intervals of increased aridity in the middle part of the succession contemporaneous with the occurrence of Homo.


Assuntos
Fósseis , Hominidae , Animais , Equidae , Europa (Continente) , Mamíferos , Perissodáctilos
2.
Ecol Lett ; 23(3): 439-446, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31854097

RESUMO

Leigh Van Valen famously stated that under constant conditions extinction probability is independent of species age. To test this 'law of constant extinction', we developed a new method using deep learning to infer age-dependent extinction and analysed 450 myr of marine life across 21 invertebrate clades. We show that extinction rate significantly decreases with age in > 90% of the cases, indicating that most species died out soon after their appearance while those which survived experienced ever decreasing extinction risk. This age-dependent extinction pattern is stronger towards the Equator and holds true when the potential effects of mass extinctions and taxonomic inflation are accounted for. These results suggest that the effect of biological interactions on age-dependent extinction rate is more intense towards the tropics. We propose that the latitudinal diversity gradient and selection at the species level account for this exceptional, yet little recognised, macroevolutionary and macroecological pattern.


Assuntos
Biodiversidade , Extinção Biológica , Animais , Evolução Biológica , Fósseis , Invertebrados
3.
Am Nat ; 188(2): 276-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27420792

RESUMO

Conventional wisdom holds that the complex shapes of deer antlers are produced under the sole influence of sexual selection. We questioned this view by demonstrating that trends for increased body size evolution passively yield more-complex ornaments, even in organisms where no effect of sexual selection is possible, with similar allometric slopes. Recent investigations suggest that sexual selection on antlers of larger deer species is stronger than that in smaller species; hence, the use of conspicuous antlers for display in large male deer is a secondary function driven by especially intense sexual selection on these large-bodied species. Since ancestral deer were small and had very simple antlers, such an intense selection on antlers shape was probably absent in early deer. Therefore, the evolution of complex ornaments is coupled with body size evolution, even in deer.


Assuntos
Chifres de Veado , Cervos , Animais , Tamanho Corporal , Masculino , Comportamento Sexual , Comportamento Sexual Animal
4.
Am Nat ; 186(2): 165-75, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26655146

RESUMO

Luxuriant, bushy antlers, bizarre crests, and huge, twisting horns and tusks are conventionally understood as products of sexual selection. This view stems from both direct observation and from the empirical finding that the size of these structures grows faster than body size (i.e., ornament size shows positive allometry). We contend that the familiar evolutionary increase in the complexity of ornaments over time in many animal clades is decoupled from ornament size evolution. Increased body size comes with extended growth. Since growth scales to the quarter power of body size, we predicted that ornament complexity should scale according to the quarter power law as well, irrespective of the role of sexual selection in the evolution and function of the ornament. To test this hypothesis, we selected three clades (ammonites, deer, and ceratopsian dinosaurs) whose species bore ornaments that differ in terms of the importance of sexual selection to their evolution. We found that the exponent of the regression of ornament complexity to body size is the same for the three groups and is statistically indistinguishable from 0.25. We suggest that the evolution of ornament complexity is a by-product of Cope's rule. We argue that although sexual selection may control size in most ornaments, it does not influence their shape.


Assuntos
Evolução Biológica , Seleção Genética , Caracteres Sexuais , Animais , Tamanho Corporal , Cefalópodes/anatomia & histologia , Cefalópodes/crescimento & desenvolvimento , Cervos/anatomia & histologia , Cervos/crescimento & desenvolvimento , Dinossauros/anatomia & histologia , Dinossauros/crescimento & desenvolvimento , Fósseis , Fractais , Filogenia
5.
Commun Biol ; 6(1): 530, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37193884

RESUMO

In 2017, a hemimandible (MW5-B208), corresponding to the Ethiopian wolf (Canis simensis), was found in a stratigraphically-controlled and radio-isotopically-dated sequence of the Melka Wakena paleoanthropological site-complex, on the Southeastern Ethiopian Highlands, ~ 2300 m above sea level. The specimen is the first and unique Pleistocene fossil of this species. Our data provide an unambiguous minimum age of 1.6-1.4 Ma for the species' presence in Africa and constitutes the first empirical evidence that supports molecular interpretations. Currently, C. simensis is one of the most endangered carnivore species of Africa. Bioclimate niche modeling applied to the time frame indicated by the fossil suggests that the lineage of the Ethiopian wolf faced severe survival challenges in the past, with consecutive drastic geographic range contractions during warmer periods. These models help to describe future scenarios for the survival of the species. Projections ranging from most pessimistic to most optimistic future climatic scenarios indicate significant reduction of the already-deteriorating territories suitable for the Ethiopian Wolf, increasing the threat to the specie's future survival. Additionally, the recovery of the Melka Wakena fossil underscores the importance of work outside the East African Rift System in research of early human origins and associated biodiversity on the African continent.


Assuntos
Lobos , Animais , Humanos , Filogenia , Espécies em Perigo de Extinção , África , Biodiversidade
6.
Sci Total Environ ; 790: 148067, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34111794

RESUMO

Many areas around the world are affected by Groundwater Level rising (GWLr). One of the most severe consequences of this phenomenon is Groundwater Flooding (GF), with serious impacts for the human and natural environment. In Europe, GF has recently received specific attention with Directive 2007/60/EC, which requires Member States to map GF hazard and propose measures for risk mitigation. In this paper a methodology has been developed for Groundwater Flooding Susceptibility (GFS) assessment, using for the first time Spatial Distribution Models. These Machine Learning techniques connect occurrence data to predisposing factors (PFs) to estimate their distributions. The implemented methodology employs aquifer type, depth of piezometric level, thickness and hydraulic conductivity of unsaturated zone, drainage density and land-use as PFs, and a GF observations inventory as occurrences. The algorithms adopted to perform the analysis are Generalized Boosting Model, Artificial Neural Network and Maximum Entropy. Ensemble Models are carried out to reduce the uncertainty associated with each algorithm and increase its reliability. GFS is mapped by choosing the ensemble model with the best predictivity performance and dividing occurrence probability values into five classes, from very low to very high susceptibility, using Natural Breaks classification. The methodology has been tested and statistically validated in an area of 14,3 km2 located in the Metropolitan City of Naples (Italy), affected by GWLr since 1990 and GF in buildings and agricultural soils since 2007. The results of modeling show that about 93% of the inventoried points fall in the high and very high GFS classes, and piezometric level depth, thickness of unsaturated zone and drainage density are the most influencing PFs, in accordance with field observations and the triggering mechanism of GF. The outcomes provide a first step in the assessment of GF hazard and a decision support tool to local authorities for GF risk management.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Agricultura , Humanos , Aprendizado de Máquina , Reprodutibilidade dos Testes
7.
BMC Evol Biol ; 10: 289, 2010 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-20854657

RESUMO

BACKGROUND: Many small vertebrates on islands grow larger, mature later, lay smaller clutches/litters, and are less sexually dimorphic and aggressive than their mainland relatives. This set of observations is referred to as the 'Island Syndrome'. The syndrome is linked to high population density on islands. We predicted that when population density is low and/or fluctuating insular vertebrates may evolve correlated trait shifts running opposite to the Island Syndrome, which we collectively refer to as the 'reversed island syndrome' (RIS) hypothesis. On the proximate level, we hypothesized that RIS is caused by increased activity levels in melanocortin receptors. Melanocortins are postranslational products of the proopiomelanocortin gene, which controls pleiotropically pigmentation, aggressiveness, sexual activity, and food intake in vertebrates. RESULTS: We tested the RIS hypothesis performing a number of behavioral, genetic, and ontogenetic tests on a blue colored insular variant of the Italian Wall lizard Podarcis sicula, living on a small island off the Southern Italian coast. The population density of this blue-colored variant was generally low and highly fluctuating from one year to the next.In keeping with our predictions, insular lizards were more aggressive and sexually dimorphic than their mainland relatives. Insular males had wide, peramorphic heads. The growth rate of insular females was slower than growth rates of mainland individuals of both sexes, and of insular males. Consequently, size and shape dimorphism are higher on the Island. As predicted, melanocortin receptors were much more active in individuals of the insular population. Insular lizards have a higher food intake rate than mainland individuals, which is consistent with the increased activity of melanocortin receptors. This may be adaptive in an unpredictable environment such as Licosa Island. Insular lizards of both sexes spent less time basking than their mainland relatives. We suspect this is a by-product (spandrel) of the positive selection for increased activity of melanocortins receptors. CONCLUSIONS: We contend that when population density is either low or fluctuating annually as a result of environmental unpredictability, it may be advantageous to individuals to behave more aggressively, to raise their rate of food intake, and allocate more energy into reproduction.


Assuntos
Comportamento Animal/fisiologia , Lagartos/fisiologia , Animais , Tamanho Corporal/fisiologia , Ingestão de Alimentos/fisiologia , Feminino , Geografia , Lagartos/classificação , Lagartos/genética , Lagartos/crescimento & desenvolvimento , Masculino , Polimorfismo Genético/genética , Densidade Demográfica , Reprodução/fisiologia
8.
iScience ; 23(11): 101693, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33163945

RESUMO

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.

9.
Front Psychol ; 9: 1493, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30174638

RESUMO

Parental bonding and emotional regulation, while important to explain difficulties that may arise in child development, have mainly been studied at an individual level. The present study aims to examine alexithymia and parental bonding in families of adolescents with psychiatric disorders through different generations. The sample included a total of 102 adolescent patients with psychiatric disorders and their parents. In order to take a family level approach, a Latent Class Analysis was used to identify the latent relationships among alexithymia (Toronto Alexithymia Scale), perceived parental bonding (Parental Bonding Instrument) and the presence of adolescent internalizing or externalizing psychiatric symptoms (Youth Self-Report). Families of internalizing and externalizing adolescents present different and specific patterns of emotional regulation and parenting. High levels of adolescent alexithymia, along with a neglectful parenting style perceived by the adolescent and the father as well, characterized the families of patients with internalizing symptoms. On the other hand, in the families with externalizing adolescents, it was mainly the mother to remember an affectionless control parental style. These results suggest the existence of an intergenerational transmission of specific parental bonding, which may influence the emotional regulation and therefore the manifestation of psychiatric symptoms.

10.
Philos Trans R Soc Lond B Biol Sci ; 371(1691): 20150220, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26977061

RESUMO

Species co-occur with different sets of other species across their geographical distribution, which can be either closely or distantly related. Such co-occurrence patterns and their phylogenetic structure within individual species ranges represent what we call the species phylogenetic fields (PFs). These PFs allow investigation of the role of historical processes--speciation, extinction and dispersal--in shaping species co-occurrence patterns, in both extinct and extant species. Here, we investigate PFs of large mammalian species during the last 3 Myr, and how these correlate with trends in diversification rates. Using the fossil record, we evaluate species' distributional and co-occurrence patterns along with their phylogenetic structure. We apply a novel Bayesian framework on fossil occurrences to estimate diversification rates through time. Our findings highlight the effect of evolutionary processes and past climatic changes on species' distributions and co-occurrences. From the Late Pliocene to the Recent, mammal species seem to have responded in an individualistic manner to climate changes and diversification dynamics, co-occurring with different sets of species from different lineages across their geographical ranges. These findings stress the difficulty of forecasting potential effects of future climate changes on biodiversity.


Assuntos
Distribuição Animal , Modelos Biológicos , Filogenia , Animais , Fósseis , Especificidade da Espécie , Fatores de Tempo
11.
Evolution ; 69(7): 1690-700, 2015 07.
Artigo em Inglês | MEDLINE | ID: mdl-26095445

RESUMO

Chewing on different food types is a demanding biological function. The classic assumption in studying the shape of feeding apparatuses is that animals are what they eat, meaning that adaptation to different food items accounts for most of their interspecific variation. Yet, a growing body of evidence points against this concept. We use the primate mandible as a model structure to investigate the complex interplay among shape, size, diet, and phylogeny. We find a weak but significant impact of diet on mandible shape variation in primates as a whole but not in anthropoids and catarrhines as tested in isolation. These clades mainly exhibit allometric shape changes, which are unrelated to diet. Diet is an important factor in the diversification of strepsirrhines and platyrrhines and a phylogenetic signal is detected in all primate clades. Peaks in morphological disparity occur during the Oligocene (between 37 and 25 Ma) supporting the notion that an adaptive radiation characterized the evolution of South American monkeys. In all primate clades, the evolution of mandible size is faster than its shape pointing to a strong effect of allometry on ecomorphological diversification in this group.


Assuntos
Evolução Biológica , Mandíbula/anatomia & histologia , Primatas/anatomia & histologia , Animais , Dieta , Feminino , Fósseis/anatomia & histologia , Masculino , Mastigação , Filogenia , Primatas/fisiologia , Especificidade da Espécie
12.
Ital Heart J Suppl ; 5(3): 209-14, 2004 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-15116866

RESUMO

BACKGROUND: Dobutamine stress echocardiography (DSE) is an imaging test widely used for risk stratification of patients after acute myocardial infarction. METHODS: We evaluated the sensitivity of DSE with respect to the gender and the stenotic coronary artery in patients who survived a myocardial infarction and with angiographic evidence of single-vessel coronary artery disease. RESULTS: The sensitivity of DSE was generally low. In particular, it was significantly lower in the presence of stenosis of the left circumflex and right coronary arteries with respect to the left anterior descending coronary artery. In females it was lower, especially when the stenosis involved the right coronary and left circumflex arteries. CONCLUSIONS: Our data suggest that in female gender the use of other imaging tests and particularly of coronarography should be strongly recommended for risk stratification after acute myocardial infarction.


Assuntos
Estenose Coronária/diagnóstico por imagem , Dobutamina , Ecocardiografia sob Estresse/métodos , Infarto do Miocárdio/diagnóstico por imagem , Angiografia Coronária , Vasos Coronários/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Prognóstico , Recidiva , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Caracteres Sexuais
13.
Ital Heart J Suppl ; 4(2): 128-32, 2003 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-12762263

RESUMO

ST-segment elevation in the presence of typical chest pain is a fundamental criterion for the diagnosis of acute myocardial infarction. We describe the case of a 62-year-old male with latent Brugada syndrome in whom the intravenous infusion of flecainide for paroxysmal atrial fibrillation caused ECG abnormalities similar to those of an acute septal myocardial infarction. The patient was not submitted to systemic thrombolysis since accurate echocardiographic evaluation was not suggestive of the presence of any wall motion abnormality and blood analysis did not reveal any increase in the levels of myocardial enzymes. The clinical outcome was not complicated and the patient was finally discharged.


Assuntos
Antiarrítmicos/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Morte Súbita Cardíaca , Eletrocardiografia/efeitos dos fármacos , Flecainida/efeitos adversos , Bloqueio Cardíaco/fisiopatologia , Síncope/fisiopatologia , Fibrilação Atrial/diagnóstico por imagem , Ecocardiografia , Bloqueio Cardíaco/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Síncope/diagnóstico por imagem , Síndrome
14.
Musculoskelet Surg ; 95(2): 89-94, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21193978

RESUMO

Patello-femoral problems are frequently encountered in knee clinic. The most important role of the patella is to increase the quadriceps efficiency, although this function could be altered in the patello-femoral instability. Active stability of the patello-femoral joint is provided by the surrounding muscles and ligaments, passive stability is provided by the bony and cartilage structures. Patellofemoral instability is defined, from Henry Dejour, as a disease without engagement the patella in the femoral trochlea during knee range of motion. Every time should be performed careful radiological preoperative investigations (radiographs and computed tomography) involving an expert musculoskeletal radiologist. Surgical procedures may be divided into those that address the soft tissues (muscles and ligaments), generally on the immature skeletal, and those that effect bony changes, generally on the mature skeletal; sometimes, it is necessary to combine soft-tissue and bony procedures. In this report, the authors describe a tibial tubercle periosteum transfer technique for patello-femoral instability in immature patients, which may potentially improve clinical results in very young symptomatic patients with patello-femoral instability.


Assuntos
Instabilidade Articular/cirurgia , Osteotomia , Luxação Patelar/cirurgia , Articulação Patelofemoral/cirurgia , Periósteo/transplante , Tíbia/cirurgia , Criança , Feminino , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Seguimentos , Humanos , Instabilidade Articular/diagnóstico por imagem , Instabilidade Articular/etiologia , Instabilidade Articular/fisiopatologia , Procedimentos Ortopédicos/métodos , Osteotomia/métodos , Luxação Patelar/diagnóstico por imagem , Luxação Patelar/etiologia , Luxação Patelar/fisiopatologia , Articulação Patelofemoral/diagnóstico por imagem , Articulação Patelofemoral/lesões , Radiografia , Amplitude de Movimento Articular , Resultado do Tratamento
15.
Evolution ; 64(5): 1489-503, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20015238

RESUMO

Mandibles and teeth of ungulates have been extensively studied to discern the functional significance of their design. Grazing ungulates have deeper mandibles, longer coronoid processes, flatter incisor arcades, and more hypsodont molars in comparison to browsers. If the functional significance of both mandible and teeth shapes is well-established, it remains uncertain to what extent mandible shapes are really adapted to grazing, meaning that they evolved either to serve their current biological function or just as a structural requirement to accommodate higher crowned molars. Here, we address this question by studying the contribution of phylogeny, hypsodonty, and body size to mandibular shape variation. The mandible shape appeared to be significantly influenced by hypsodonty but not by body size. Interestingly, hypsodonty-related changes influenced the tooth row in artiodactyls and perissodactyls significantly but in the opposite directions, which is ultimately related to their different digestive strategies. Yet, we obtained a strong phylogenetic effect in perissodactyls, suggesting that their mandible shape should be strongly inherited. The strength of this effect was not significant within artiodactyls (where hypsodonty explained much more variance in mandible shape). Digestive strategy is deemed to interplay with hypsodonty to produce different paths of adaptation to particular diets in ungulates.


Assuntos
Adaptação Fisiológica , Mamíferos/fisiologia , Mandíbula/anatomia & histologia , Animais , Tamanho Corporal , Comportamento Alimentar , Mamíferos/anatomia & histologia , Filogenia
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