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Abstract Biologists have long noted that endotherms tend to have larger bodies (Bergmann’s rule) and shorter appendages (Allen’s rule) in colder environments. Nevertheless, many taxonomic groups appear not to conform to these ‘rules’, and general explanations for these frequent exceptions are currently lacking. Here we note that by combining complementary changes in body and extremity size, lineages could theoretically respond to thermal gradients with smaller changes in either trait than those predicted by either Bergmann’s or Allen’s rule alone. To test this idea, we leverage geographic, ecological, phylogenetic, and morphological data on 6,974 non-migratory terrestrial bird species, and show that stronger family-wide changes in bill size over thermal gradients are correlated with more muted changes in body size. Additionally, we show that most bird families exhibit weak but appropriately directed changes in both traits, supporting the notion of complementarity in Bergmann’s and Allen’s rules. Finally, we show that the few families that exhibit significant gradients in either bill or body size, tend to be more speciose, widely distributed, or ecologically constrained. Our findings validate Bergmann’s and Allen’s logic and remind us that body and bill size are simply convenient proxies for their true quantity of interest: the surface-to-volume ratio.

Jared Diamond suggested that the unique East–West orientation of Eurasia facilitated the spread of cultural innovations and gave it substantial political, technological and military advantages over other continental regions. This controversial hypothesis assumes that innovations can spread more easily across similar habitats, and that environments tend to be more homogeneous at similar latitudes. The resulting prediction is that Eurasia is home to environmentally homogenous corridors that enable fast cultural transmission. Despite indirect evidence supporting Diamond's influential hypothesis, quantitative tests of its underlying assumptions are currently lacking. Here we address this critical gap by leveraging ecological, cultural and linguistic datasets at a global scale. Our analyses show that although societies that share similar ecologies are more likely to share cultural traits, the Eurasian continent is not significantly more ecologically homogeneous than other continental regions. Our findings highlight the perils of single factor explanations and remind us that even the most compelling ideas must be thoroughly tested to gain a solid understanding of the complex history of our species.

This study investigates and compares plasma electrolytic oxidation (PEO) coatings produced on wrought Ti6Al4V alloy substrates with those resulting from electron beam powder bed fusion (PBF-EB). For a duration of 1000 s, a phosphate/silicate electrolyte with a current density of 50 A/cm2 was employed to fabricate the coatings. Surface and polished cross-sections of the coated specimens underwent SEM and X-ray diffraction (XRD) analyses. The obtained coatings exhibit differences of up to approximately 18% in thickness and formation, as well as in their anatase phase. The anatase phase is present at a level of 54.09% in the substrates processed by PBF-EB and 38.54% in wrought substrates. After 1000 s of PEO, the coatings formed on the wrought substrates exhibited higher porosity and larger pores (>1 μm) compared to those produced on the PBF-EB specimens. The PBF-EB coatings had lower porosity because they contained fewer pores larger than 1 μm. The findings imply that the unique microstructural arrangement of PBF-EB-produced additively made Ti6Al4V materials plays a significant impact in the development and morphological properties of PEO oxide coatings.

Traits that facilitate adaptive responses to novel environments may facilitate global radiations. Here, the authors describe diversification dynamics of crows, finding that their global radiation coincides with high rates of phenotypic and climatic niche evolution.

Abstract Resource managers have rarely accounted for evolutionary dynamics in the design or implementation of climate change adaptation strategies. We brought the research and management communities together to identify challenges and opportunities for applying evidence from evolutionary science to support on‐the‐ground actions intended to enhance species' evolutionary potential. We amalgamated input from natural‐resource practitioners and interdisciplinary scientists to identify information needs, current knowledge that can fill those needs, and future avenues for research. Three focal areas that can guide engagement include: (1) recognizing when to act, (2) understanding the feasibility of assessing evolutionary potential, and (3) identifying best management practices. Although researchers commonly propose using molecular methods to estimate genetic diversity and gene flow as key indicators of evolutionary potential, we offer guidance on several additional attributes (and their proxies) that may also guide decision‐making, particularly in the absence of genetic data. Finally, we outline existing decision‐making frameworks that can help managers compare alternative strategies for supporting evolutionary potential, with the goal of increasing the effective use of evolutionary information, particularly for species of conservation concern. We caution, however, that arguing over nuance can generate confusion; instead, dedicating increased focus on a decision‐relevant evidence base may better lend itself to climate adaptation actions.

Abstract There is an imperative for conservation practitioners to help biodiversity adapt to accelerating environmental change. Evolutionary biologists are well‐positioned to inform the development of evidence‐based management strategies that support the adaptive capacity of species and ecosystems. Conservation practitioners increasingly accept that management practices must accommodate rapid environmental change, but harbour concerns about how to apply recommended changes to their management contexts. Given the interest from both conservation practitioners and evolutionary biologists in adjusting management practices, we believe there is an opportunity to accelerate the required changes by promoting closer collaboration between these two groups. We highlight how evolutionary biologists can harness lessons from other disciplines about how to foster effective knowledge exchange to make a substantive contribution to the development of effective conservation practices. These lessons include the following: (1) recognizing why practitioners do and do not use scientific evidence; (2) building an evidence base that will influence management decisions; (3) translating theory into a format that conservation practitioners can use to inform management practices; and (4) developing strategies for effective knowledge exchange. Although efforts will be required on both sides, we believe there are rewards for both practitioners and evolutionary biologists, not least of which is fostering practices to help support the long‐term persistence of species.

Nearly 17% of all bird species are hosts to obligate brood parasites like the common cuckoo. Antonson et al. show that parasite species hedge their reproductive bets by outsourcing parental care to a greater variety of host species when the rearing environment for their young is more unpredictable.

Abstract Extreme weather events are becoming more frequent, severe, and/or widespread as a consequence of anthropogenic climate change. While the economic and ecological implications of these changes have received considerable attention, the role of evolutionary processes in determining organismal responses to these critical challenges is currently unknown. Here we develop a novel theoretical framework that explores how alternative pathways for adaptation to rare selection events can influence population‐level vulnerabilities to future changes in the frequency, scope, and intensity of environmental extremes. We begin by showing that different life histories and trait expression profiles can shift the balance between additive and multiplicative properties of fitness accumulation, favoring different evolutionary responses to identical environmental phenomena. We then demonstrate that these different adaptive outcomes lead to predictable differences in population‐level vulnerabilities to rapid increases in the frequency, intensity, or scope of extreme weather events. Specifically, we show that when the primary mode of fitness accumulation is additive, evolution favors ignoring environmental extremes and lineages become highly vulnerable to extinction if the frequency or scope of extreme weather events suddenly increases. Conversely, when fitness accumulates primarily multiplicatively, evolution favors bet‐hedging phenotypes that cope well with historical extremes and are instead vulnerable to sudden increases in extreme event intensity. Our findings address a critical gap in our understanding of the potential consequences of rare selection events and provide a relatively simple rubric for assessing the vulnerabilities of any population of interest to changes in a wide variety of extreme environmental phenomena.

Large brains are expected to be beneficial in variable environments by enabling flexible behavioral responses. Here, the authors show that relative brain size in birds is bimodally distributed in colder, seasonal environments, suggesting that both large and small brains can be adaptive solutions to harsh conditions.

Social inequality is ubiquitous in contemporary human societies, and has deleterious social and ecological impacts. However, the factors that shape the emergence and maintenance of inequality remain widely debated. Here we conduct a global analysis of pathways to inequality by comparing 408 non-industrial societies in the anthropological record (described largely between 1860 and 1960) that vary in degree of inequality. We apply structural equation modelling to open-access environmental and ethnographic data and explore two alternative models varying in the links among factors proposed by prior literature, including environmental conditions, resource intensification, wealth transmission, population size and a well-documented form of inequality: social class hierarchies. We found support for a model in which the probability of social class hierarchies is associated directly with increases in population size, the propensity to use intensive agriculture and domesticated large mammals, unigeniture inheritance of real property and hereditary political succession. We suggest that influence of environmental variables on inequality is mediated by measures of resource intensification, which, in turn, may influence inequality directly or indirectly via effects on wealth transmission variables. Overall, we conclude that in our analysis a complex network of effects are associated with social class hierarchies.

Background Experimental evolution of microbes can be used to empirically address a wide range of questions about evolution and is increasingly employed to study complex phenomena ranging from genetic evolution to evolutionary rescue. Regardless of experimental aims, fitness assays are a central component of this type of research, and low-throughput often limits the scope and complexity of experimental evolution studies. We created an experimental evolution system in Saccharomyces cerevisiae that utilizes genetic barcoding to overcome this challenge. Results We first confirm that barcode insertions do not alter fitness and that barcode sequencing can be used to efficiently detect fitness differences via pooled competition-based fitness assays. Next, we examine the effects of ploidy, chemical stress, and population bottleneck size on the evolutionary dynamics and fitness gains (adaptation) in a total of 76 experimentally evolving, asexual populations by conducting 1,216 fitness assays and analyzing 532 longitudinal-evolutionary samples collected from the evolving populations. In our analysis of these data we describe the strengths of this experimental evolution system and explore sources of error in our measurements of fitness and evolutionary dynamics. Conclusions Our experimental treatments generated distinct fitness effects and evolutionary dynamics, respectively quantified via multiplexed fitness assays and barcode lineage tracking. These findings demonstrate the utility of this new resource for designing and improving high-throughput studies of experimental evolution. The approach described here provides a framework for future studies employing experimental designs that require high-throughput multiplexed fitness measurements.

Leclercia adecarboxylata is a member of the Enterobacteriaceae family that has been isolated from several environmental and animal specimens, however it rarely causes diseases in human beings. It has natural resistance to several antibiotics, and has shown the ability to harbor and produce enzymes capable of hydrolyzing most of the antibiotics used in daily clinical practice, making its treatment a challenge when a strain with such characteristics causes disease. Here we report the first known case of infection by Leclercia adecarboxylata after a trauma with plant material, in a 69-year-old male patient, with poorly controlled Diabetes Mellitus type 2.

In 2015, we investigated Bartonella quintana and typhus group rickettsiae in body lice from homeless persons in Bogotá, Colombia. We found B. quintana–infected body lice and seroprevalence of this microorganism in 19% of homeless persons and typhus group rickettsiae in 56%. Public health professionals should start preemptive measures and active vector control.

Summary: Spoted fever group (SFG) rickettsioses are actually considered as emerging and re-emerging zoonotic diseases, caused by pathogenic bacteria of the spotted fever group rickettsiae (SFGR). Recently, serologic studies in human and animals conducted in Colombian Orinoquia, showed a high seroprevalence against SFGR. In June 2015, a 50-year-old male was admitted to a hospital in Bogotá, Colombia, with two days of malaise and temperature of 39 °C, associated to generalized rash 24 h after the onset of fever. He referred a work visit and outdoor activities in rural area of the Department of Meta 15 days prior the onset of symptoms. The patient was transferred to the intensive care unit with supplementary oxygen, inotropic support and was assessed by the infectious diseases department, indicating the addition of Doxycycline. After seven days of antibiotic treatment the patient was discharged with no evidence of new symptoms or sequels. Retrospectively, two serum samples collected during the acute and convalescent phase were evaluated; there was four fold rise in titer against SFGR. With the foregoing, associated with the recent serological evidence that suggests the circulation of SFGR species in the Colombian Orinoquia, we consider to recognize this region as a new endemic area for SFG Rickettsioses. Keywords: Rickettsia, Rickettsia infections, Spotted fever group, Colombia

The evolution of agriculture improved food security and enabled significant increases in the size and complexity of human groups. Despite these positive effects, some societies never adopted these practices, became only partially reliant on them, or even reverted to foraging after temporarily adopting them. Given the critical importance of climate and biotic interactions for modern agriculture, it seems likely that ecological conditions could have played a major role in determining the degree to which different societies adopted farming. However, this seemingly simple proposition has been surprisingly difficult to prove and is currently controversial. Here, we investigate how recent agricultural practices relate both to contemporary ecological opportunities and the suitability of local environments for the first species domesticated by humans. Leveraging a globally distributed dataset on 1,291 traditional societies, we show that after accounting for the effects of cultural transmission and more current ecological opportunities, levels of reliance on farming continue to be predicted by the opportunities local ecologies provided to the first human domesticates even after centuries of cultural evolution. Based on the details of our models, we conclude that ecology probably helped shape the geography of agriculture by biasing both human movement and the human-assisted dispersal of domesticates.

How humans obtain food has dramatically reshaped ecosystems and altered both the trajectory of human history and the characteristics of human societies. Our species' subsistence varies widely, from predominantly foraging strategies, to plant-based agriculture and animal husbandry. The extent to which environmental, social and historical factors have driven such variation is currently unclear. Prior attempts to resolve long-standing debates on this topic have been hampered by an over-reliance on narrative arguments, small and geographically narrow samples, and by contradictory findings. Here we overcome these methodological limitations by applying multi-model inference tools developed in biogeography to a global dataset (818 societies). Although some have argued that unique conditions and events determine each society's particular subsistence strategy, we find strong support for a general global pattern in which a limited set of environmental, social and historical factors predicts an essential characteristic of all human groups: how we obtain our food.

Molluscum Contagiosum (MC) is a skin infection caused by a double-stranded DNA virus of the family Poxviridae that replicates in the human epidermis, affecting mainly children and young sexually active adults and causing flesh colored papular lesions with central umbilication with an average size of 3-5 mm, although atypical lesions that reach great size (Giant Molluscum Contagiosum), 10-15 mm, can be seen in almost any immunodeficiency condition. We report the case of a 35 year old male patient with C3 HIV disease with an abdominal pathology associated to skin lesions predominantly in the forehead and scalp that reached sizes over 5 mm, diagnosed as Giant Molluscum Contagiosum by skin biopsies.

Colombian physician Luis Benigno Patiño Camargo was one of the pioneers in the study of rickettsioses in South America, demonstrating for the first time in Colombia the presence of Rickettsia rickettsii as the etiological agent of a highly deadly exanthematic febrile syndrome in the 1930s. However, Patiño-Camargo performed other investigations from 1917-1943, which represent the first descriptions and scientific evidence of the presence of R. prowazekii and R. typhi in Colombia. Almost 60 years after the latest research conducted by Dr. Patiño-Camargo, rickettsioses were again a matter of interest and research. In the last decade over 20 research studies have been published, showing new endemic areas for R. rickettsii, as well as the description of new rickettsial species in Colombia.

Animal societies are typically divided into those in which reproduction within a group is monopolized by a single female versus those in which it is shared among multiple females. It remains controversial, however, whether these two forms of social structure represent distinct evolutionary outcomes or endpoints along a continuum of reproductive options. To address this issue and to determine whether vertebrates and insects exhibit the same patterns of variation in social structure, we examined the demographic and reproductive structures of 293 species of wasps, ants, birds and mammals. Using phylogenetically informed comparative analyses, we found strong evidence indicating that not all reproductive arrangements within social groups are viable in nature and that in societies with multiple reproductives, selection favours instead taxon-specific patterns of decrease in the proportion of breeders as a function of group size. These outcomes suggest that the selective routes to sociality differ depending upon whether monopolization of reproduction by one individual is possible and that variation within and among taxonomic groups may lead to the false perception of a continuum of social structures. Thus, the occurrence of very large societies may require either complete reproductive monopolization (monogyny/singular breeding) or the maintenance of a taxon-specific range of values for the proportional decrease in the number of breeders within a group (polygyny/plural breeding), both of which may reduce reproductive conflict among females.

El presente artículo esta orientado describir el pasado, el presente y las tendencias de la formación de valores en la educación superior colombiana. Inicialmente se hace un recuento histórico de las diferentes épocas de la educación colombiana, la cual estuvo influenciada desde sus comienzos por la religión católica tendencia que permaneció incólume desde la colonia hasta finales de 1970. Posteriormente y en especial en las postrimerías del siglo XX, se presentaron varios acontecimientos que incidieron para que el objetivo de formar valores fuera perdiendo importancia hasta quedar totalmente relegado, estos sucesos fueron : a) el vertiginoso avance científico y técnico que se presentó después de los años setenta incidiendo para que nuestros directivos encargados de orientar la políticas de la educación superior terminaran privilegiando, la instrucción sobre la educación y b) los fenómenos de narcotráfico, guerrilla y corrupción que han venido recorriendo nefastamente, el territorio nacional transformaron el tejido axiológico sobre el cual se cimentaba la sociedad colombiana. Por fortuna con el advenimiento del siglo XXI, la formación en: ética, moral y valores se ha convertido en una recomendación universal emanada desde la UNESCO. En los foros y congresos sobre educación e los ámbitos: internacional, nacional, regional y locales, el tema de formación en valores ha saltado a la palestra y se ha convertido en una tendencia de primera línea. En este sentido, la educación superior colombiana deberá hacer un gran esfuerzo en los próximos años para recuperar la formación integral de estudiante colombiano, deberá por tanto diseñar políticas, establecer programas y trazar tareas que permitan recuperar la urdimbre axiológica, visión explicitada en la parte final de este artículo para que en nuestras facultades y carreras se introduzcan mecanismos que permitan formar ciudadanos integrales esto es: instruidos y éticos.

In the first decades of the 20th century, scientific papers were published suggesting the presence of Tick-Borne Relapsing Fever in Colombia. As a contribution, we present some historical aspects referring to this topic.

We report on the case of a 32 year-old man with no laboral exposure to lead but who received a gunshot, seven years before, in the right coxofemoral joint; he developed classic manifestations of plumbism and had a blood lead level of 99 119/dl. This value decreased and the clinical and laboratory abnormalities improved after surgical removal of the retained bullet. We discuss the sparse literature available on this subject and emphasize the importance of performing periodic controls of blood lead levels to all patients with bullets retained in the joints. Se presenta el caso de un paciente de 32 anos con antecedente de herida por bala en la articulación coxofemoral derecha, 6 anos antes, sin exposición laboral al plomo, quien presentó un cuadro clásico de saturnismo y niveles de plumbemia de 99 µg/dl; después de la extracción de la bala hubo mejoría clínica y de laboratorio, incluyendo disminución de dichos niveles. Se revisa y discute la escasa literatura existente al respecto haciendo énfasis en la importancia de un seguimiento periódico, con determinaciones de plomo en sangre a todo paciente con heridas por bala cuando el proyectil queda retenido en una articulación.

Background: Jumping and sprinting are essential skills for several sports, especially for soccer, since they allow to determine neuromuscular function and maximum power of the lower extremities in athletes. This study aimed to establish the relationship between vertical jump performance and sprint speed at 20 m and 50 m in professional soccer players. Methods: This study took place from June 2020 to November 2021 with participants from the U20 category of the Colombian professional team Fortaleza CEIF, and the U18 category of the Brazilian professional team Boston City. The vertical jump was assessed with the countermovement jump (CMJ), squat jump (SJ), and rebound jump (RJ) variants using the WheelerJump jump sensor while the sprint was measured using the Winlaborat horizontal encoder. Results: 200 participants from the selected teams were included in this study. Almost perfect correlations (p < 0,05 – r: 0.97) and excellent coefficients of determination (R 2: 0.95 – 0.93) were observed between the reactive force index with the mean height of the different jump protocols and the 50-meter sprint speed, indicating that the higher the altitude and/or the higher the reactive force index, the higher the 50-meter sprint speed. The same behavior was found with the 20-meter race, but the correlation levels (p Conclusions: The results of this study suggest that, in professional soccer players, long sprint performance like 50 m is strongly correlated and could be accuracy explained by the average height reached in SJ, CMJ, and RJ and by the ability to perform repeated jumps using short contact times, thus increasing the ground reaction forces, which translates into a similar behavior during successive contacts of the player's feet against the ground during the race.

La pielonefritis enfisematosa es una infección necrosante del parénquima renal que puede afectar los tejidos perirrenales y cuyo espectro de presentación clínica, por esa razón, es variable (choque séptico, acidosis metabólica, hiperglucemia, hipoglucemia, falla renal, delirio, entre otros); la mayoría de los casos se han informado en pacientes con diabetes mellitus o presencia de uropatía obstructiva. Reportamos el caso de una paciente joven no diabética quien presentó pielonefritis enfisematosa como condición clínica que lleva al diagnóstico inicial de infección por VIH, sin otras comorbilidades relacionadas, exitosamente tratada con manejo quirúrgico y antibioticoterapia. Se realizó una búsqueda sistemática de la literatura, en la cual no se ha informado esta enfermedad como manifestación clínica que lleve al diagnóstico inicial de la infección por VIH.

Gonococcal keratoconjunctivitis is a rapidly progressing and aggressive infection caused by Neisseria gonorrhoeae . We report a case of a patient who presented keratoconjunctivitis with an opacity in the left cornea that progressed into an ulcerative lesion despite initial treatment with antibiotic eye drops. Gram stains from the purulent discharge of the left eye showed gram-negative diplococci, and the culture from the ocular discharge was positive for Neisseria gonorrhoeae . Resolution was achieved with the administration of 2 g of intramuscular ceftriaxone in a single dose, and the patient had no sequelae.

Diabetic muscle infarction (DMI) is a rare yet serious complication that has been strongly associated with uncontrolled diabetes, although other risk factors are unclear. DMI is an uncommon complication of diabetes with a lack of structured guidelines for evaluation or management. End-stage renal disease (ESRD) could have further implications in patients with DMI in terms of management given that nonsteroidal anti-inflammatory drugs (NSAIDs), which have been shown to reduce the recovery times and recurrence of DMI, could be contraindicated. We present a rare case of DMI in an African American man with ESRD who presented for new-onset right lower-extremity pain and swelling. We discuss the challenges involved with the diagnosis and treatment of this rare condition. This case adds to the knowledge of DMI, which is limited because of the low incidence of this condition, and it helps us understand how this condition affects the African American population and patients with ESRD. [ABSTRACT FROM AUTHOR]