Universidad de Antioquia (Colombia) | Biology

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- by Cristina Lopez-Gallego and +1
  Alvaro Idarraga
- •

Reduced habitat quality after fragmentation can signiWcantly aVect population viability, but the eVects of diVering quality of the remaining habitat on population Wtness are rarely evaluated. Here, I compared fragmented populations of the... more

Like many species, the model plant Arabidopsis thaliana exhibits multiple different life histories in natural environments. We grew mutants impaired in different signaling pathways in field experiments across the species’ native European... more

Habitat degradation can result in drastic environmental changes potentially affecting the life-history of populations and aspects of the reproductive biology and the genetic structure within and among populations. Here, we explore how... more

Habitat differences might promote adaptive differentiation among populations that can be evidenced by genotype-by-environment interactions (GxE). I examined GxE in seed germination and seedling survival in demes of a rainforest cycad... more

Rapid evolution may be common in human-dominated landscapes where environmental changes are severe. We used phenotypic selection analyses and a markerbased method to estimate genetic variances and covariances to predict the potential... more

The taxonomy of Zamia montana and Z. oligodonta, two poorly understood species occurring at high elevations in the Western Cordillera of Colombia, is discussed. Zamia oligodonta was recently synonymized under Z. montana, but information... more

Estimación de heredabilidad y correlaciones genéticas en caracteres morfológicos y fisiológicos para una población de Zamia obliqua A.Br. (Zamiaceae: Cycadales) Estimation of heritability and genetic correlations in morphological and... more

Estimación de heredabilidad y correlaciones genéticas en caracteres morfológicos y fisiológicos para una población de Zamia obliqua A.Br. (Zamiaceae: Cycadales) Estimation of heritability and genetic correlations in morphological and physiological traits for a population of Zamia obliqua A.Br. (Zamiaceae: Cycadales) Resumen La respuesta a la selección natural en caracteres cuantitativos en una población natural depende de la magnitud de variabilidad genética y las correlaciones genéticas en los rasgos, y estos parámetros genéticos pueden diferir entre categorías de rasgos. En este estudio se caracterizaron los patrones de varianza y covarianza fenotípica y se realizaron estimaciones de heredabilidad (h 2) y correlaciones genéticas de rasgos morfológicos y fisiológicos en una población de Zamia obliqua (Zamiaceae: Cycadales). Se probaron las hipótesis de que la varianza y la heredabilidad de rasgos morfológicos son mayores que las de rasgos fisiológicos, y que las correlaciones fenotípicas y genéticas son mayores dentro que entre las categorías de rasgos. Los valores de varianza fenotípica fueron mayores en los rasgos fisiológicos comparados con los caracteres morfológicos. Los estimativos de heredabilidad sugieren que los caracteres morfológicos presentan mayor varianza genética que los rasgos fisiológicos. Por otro lado, no se obtuvieron correlaciones genéticas significativas entre los rasgos. Sin embargo, las correlaciones fenotípicas muestran mayor correlación dentro de los caracteres morfológicos que dentro de los fisiológicos o entre rasgos morfológicos y fisiológicos. Estas estimaciones de parámetros genéticos permiten construir hipótesis sobre la evolución de caracteres fenotípicos en poblaciones naturales, y son aportes importantes al estudio de la ecología evolutiva de especies no modelo y sus poblaciones en hábitats naturales. Abstract The response to natural selection of quantitative traits in a natural population depends on the magnitude of genetic variability and genetic correlations between traits, and these genetic parameters can differ between trait categories. In this study we characterized the patterns of phenotypic variance and covariance and estimated heritability and genetic correlation of morphological and physiological traits in a population of Zamia oblique (Zamiaceae: Cycadales). We tested the hypothesis that variance and heritability values are higher for morphological than for physiological traits, and that phenotypic and genetic correlations are larger within than between trait categories. Phenotypic variance values were higher for physiological traits than for morphological characters. Heritability estimates suggested that morphological traits had a higher genetic variance than physiological traits. On the other hand, significant estimates of genetic correlations among traits were not obtained. Nevertheless, phenotypic correlations show a higher correlation within morphological traits than within physiological traits or among physiological and morphological traits. These kinds of estimates for genetic parameters can help generate hypotheses about the evolution of phenotypic traits in natural populations, and represent important contributions to the study of evolutionary ecology in non-model species and their populations in natural habitats.

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- by Natalia Gomez-Lopera and +1
  Cristina Lopez-Gallego
- •
- 2
  Quantitative Genetics, Evolutionary Ecology

In addition to habitat loss and fragmentation, habitat degradation can have important consequences for biodiversity and population persistence, including effects on ecological and genetic processes beyond decreased demographic viability... more

In addition to habitat loss and fragmentation, habitat degradation can have important consequences for biodiversity and population persistence, including effects on ecological and genetic processes beyond decreased demographic viability and the loss of genetic variation. Particularly interesting is the potential for evolutionary changes and adaptation to degraded habitats, that can affect population viability even in the short-term. Here, I explore how environmental changes after habitat degradation affect the evolutionary dynamics of populations of the rainforest cycad Zamia fairchildiana, specifically how habitat degradation affects gene dispersal, inbreeding, directional selection, and genotype-by-environment interactions, and the potential for genetic differentiation between populations. Colonies of Z. fairchildiana showed little genetic differentiation in neutral molecular markers across study sites, thus can be considered as subpopulations. Subpopulations in the disturbed habitat are experiencing different environmental conditions when compared to subpopulation in their native habitat. Disturbed-habitat subpopulations showed a faster life-history. This faster life history is associated with a weaker spatial genetic structure and higher levels of inbreeding in the disturbed-habitat subpopulations. In addition, higher light availability in the disturbed habitat seems to be a major agent of selection on traits like leaf production that have the potential to respond to selection in these subpopulations. Different traits were under selection in the native-habitat subpopulations, suggesting the potential for genetic differentiation between native and disturbed-habitat subpopulations. Genotype by environment interactions in seed germination and seedling survival, in response to light and water availability, further suggested that subpopulations can adaptively diverge between habitats, but the relative role of genetic and environmental factors, particularly maternal effects, on the magnitude and rate of genetic differentiation between subpopulations remains to be evaluated. These results suggest that habitat degradation can have important consequences for the evolutionary dynamics of populations of this cycad, not necessarily typical of habitat loss and fragmentation. This study identified factors and processes important for population persistence in degraded habitats, but population responses to habitat degradation are complex. Thus further studies and long-term experiments are required for better understanding the effects of habitat degradation on population viability.

La filosofía de la mente nació como una rama especializada de la filosofía en el siglo XX y ha tenido un desarrollo considerable, al punto de ser una de las ramas más activas e innovadoras de la filosofía contemporánea. Además, dado que... more

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- by Cristina Lopez-Gallego
- •
- Ecology

Because cycad species are long lived and in many cases populations are small, studies of population dynamics are challenging. In this paper, I pres ent examples of field studies complemented by studies in controlled conditions that can... more

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- by Cristina Lopez-Gallego
- •
- Ecology

Zamia paucifoliolata, a new cycad species from the Pacific lowlands of Valle del Cauca, Colombia, is described and illustrated. It is distinguished from other species of Zamia by having an underground stem typically bearing large solitary... more

Zamia paucifoliolata, a new cycad species from the Pacific lowlands of Valle del Cauca, Colombia, is described and illustrated. It is distinguished from other species of Zamia by having an underground stem typically bearing large solitary leaves with eighteen or fewer leaflets, villous strobilar axes, microsporangia borne on both the abaxial and adaxial side of microsporophylls, and seeds that are longer than 18 mm. It is compared to Z. pyrophylla, Z. cunaria, and Z. ipetiensis, species which it most closely resembles. Resumen Se describe y se ilustra Zamia paucifoliolata, una nueva especie de cícada de las tierras bajas del Pacífico Colombiano del Valle del Cauca. Se distingue de otras especies de Zamia por su tallo subterráneo típicamente cargando hojas solitarias con 18 folíolos o menos, ejes estrobilares vellosos, presencia de microesporangios en el lado abaxial y adaxial de los microesporofilos, y semillas de mas de 18 mm de longitud. Se compara con Z. pyrophylla, Z. cunaria, y Z. ipetiensis, las especies a las que más se asemeja. Palabras clave: Chocó biogeográfico, sistemática, taxonomía Introduction With 78 species, the neotropical genus Zamia Linnaeus (1763: 1659) is the most speciose and broadly distributed genus in the New World (Calonje et al. 2018). Colombia hosts over a quarter of all Zamia species, making it the most species-rich country for the genus. A considerable amount of academic and taxonomic research on Colombian zamias has taken place over the last decade, including several new species descriptions (Lindstrom & Idarraga 2009, Calonje et al. 2010, Calonje et al. 2011, Calonje et al. 2012a, Stevenson et al. 2018) as well as taxonomic revisions (Lindstrom 2009, Calonje et al. 2012b, Calonje et al. 2015). Despite these recent and significant advances in Colombian Zamia systematics, additional research is still required, because several species remain undescribed or poorly understood, especially in the Amazonian region. A visit in 2009 by the first author to the CUVC herbarium (Cali, Colombia) revealed an enigmatic Zamia specimen (Gil Cardona et al. 577) collected in 2002 in coastal forests of the Buenaventura municipality in Valle del Cauca, Colombia. The specimen consisted of a mature seed strobilus without any accompanying vegetative material. The strobilus had an extremely long peduncle unlike any other species known in the Valle del Cauca, but somewhat resembled that of Chocoan endemic species Z. pyrophylla Calonje et al. (2010: 80), albeit with much larger seeds. Recent expeditions to this region has revealed this enigmatic taxon to be an undescribed species, which we formally describe below. The new species has morphological affinities

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- by Cristina Lopez-Gallego
- •
- Plant Taxonomy

Two major lineages of beetles inhabit cycad cones in the New World: weevils (Curculionoidea) in the subtribe Allocorynina, including the genera Notorhopalotria Tang and O'Brien, Parallocorynus Voss, Protocorynus O'Brien and Tang and... more

To determine the allelic and genotype frequencies of apolipoproteine E (APOE) gene in a representative sample of the adult population of Medellin in 2010. A representative sample of the adult population of Medellin, was obtained by means... more

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- by Gabriel Berrío and +1
  Juan Arango Viana
- •

El objetivo del estudio fue describir la calidad de vida relacionada con la salud (CvRS) y su asociación con aspectos sociodemográficos, el exceso de peso u obesidad y la actividad física (aF) en un grupo de adolescentes de la ciudad de... more

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- by Gabriel Berrío and +1
  Revista Colombiana de Psicología (RCP)
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- 3
  Psychology, Psicología de la salud, Calidad de vida en salud

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