Heiber Cárdenas-Henao

Genetic structure of the red mangrove ( Rhizophora mangle L.) on the Colombian Pacific detected by microsatellite molecular markers

AbstractRhizophora mangle, one of the five species of the genus Rhizophora, is found widely distributed along the American and West African coasts. This species is one of the principal constituents of the mangrove ecosystem in Colombia and is also found within the most important economic activities for the communities that inhabit the littoral. In order to assess the degree of genetic diversity of R. mangle in five populations of the Colombian Pacific, nuclear microsatellite molecular markers were used. In 92 individuals sampled, it was found that 100% of the loci were polymorphic

Blood puncture as a nondestructive sampling tool to obtain DNA in frogs: comparison of protocols and survival analysis.

(\overline H _0 = 0.494)

Evidence for adaptive divergence of thermal responses among Bemisia tabaci populations from tropical Colombia following a recent invasion.

, and no private alleles were detected. The population structure of R. mangle in the Colombian Pacific, was highly significant (P < 0.001); however, the greatest differentiation was detected at the within-population level (94.62%). For the populations of La Plata, Virudó and Charambirá, the tendency toward panmixia could be the cause of the low differentiation among these three locations. Within populations, the genetic diversity revealed a deviation from Hardy–Weinberg equilibrium with high significance in Virudó and Tumaco, where it appears the intense anthropogenic activity has exercised strong pressure on the red mangrove, resulting in the possible fragmentation of the local landscape and therefore an increase in the rate of endogamy within these populations. Despite this situation, our study―one of the first developed in genetics of the red mangrove in Colombia―did not show evidence of recent bottleneck effects or deterioration in its genetic composition, which could be exploited to propose management and restoration programs for the zones where the forests of this species are degraded.

A likelihood inference of historical biogeography in the world's most diverse terrestrial vertebrate genus: diversification of direct-developing frogs (Craugastoridae: Pristimantis) across the Neotropics.

In molecular biology studies of Anura, nondestructive methods to obtain genetic material are needed as alternatives to toe clipping. This work evaluates a nondestructive method for sampling DNA from blood puncture, comparing the performance of three different extraction protocols (Qiagen Kit, Salting‐out and Chelex). We collected 134 individuals of Eleutherodactylus johnstonei, extracting blood via puncture of the medial vein using commercial‐grade glucometer lancets. We extracted 100–1880 ng DNA, finding no differences between the extraction protocols. We compared the quality of the resulting DNA through amplification and sequencing of the 16S mitochondrial gene. Amplification was successful for the three extraction protocols, although Chelex showed better performance, making it the most recommendable protocol for extraction of DNA from blood. The resulting sequences corresponded to those registered in the GenBank for this species. Additionally, we found no significant differences in survival or weight change between the individuals that were manipulated and a control group (mean survival 66.7% treated, 62.9% untreated). Data reveal that blood samples obtained by puncture are a convenient alternative to other tissues (phalange, buccal swab, liver) that have traditionally been used as DNA sources for anurans. The technique is applicable to small and large species, covering most anuran diversity, provides enough DNA for many genetic applications and produces no noticeable effect on the survival or performance, given that it does not affect the motor parts or the dexterity of the animals.

Thermal reaction norms between populations with climatic differences of the invader silverleaf whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) MEAM 1 clade in Colombia

There is an increasing evidence that populations of ectotherms can diverge genetically in response to different climatic conditions, both within their native range and (in the case of invasive species) in their new range. Here, we test for such divergence in invasive whitefly Bemisia tabaci populations in tropical Colombia, by considering heritable variation within and between populations in survival and fecundity under temperature stress, and by comparing population differences with patterns established from putatively neutral microsatellite markers. We detected significant differences among populations linked to mean temperature (for survival) and temperature variation (for fecundity) in local environments. A QST − FST analysis indicated that phenotypic divergence was often larger than neutral expectations (QST > FST). Particularly, for survival after a sublethal heat shock, this divergence remained linked to the local mean temperature after controlling for neutral divergence. These findings point to rapid adaptation in invasive whitefly likely to contribute to its success as a pest species. Ongoing evolutionary divergence also provides challenges in predicting the likely impact of Bemisia in invaded regions.

Epithelial mucosa as an alternative tissue for DNA extraction in amphibians

The geology of the northern Andean region has driven the evolutionary history of Neotropical fauna through the creation of barriers and connections that have resulted in speciation and dispersal events, respectively. One of the most conspicuous groups of anuran fauna in the Andes and surrounding areas is the direct-developing species of the genus Pristimantis. We investigated the molecular phylogenetic placement of 12 species from the montane Andes of Colombia in a broader geographical context with a new genus-level phylogeny in order to identify the role of Andean orogeny over the last 40million years and the effect of elevational differences in diversification of Pristimantis. We examined the biogeographic history of the genus using ancestral range reconstruction by biogeographic regions and elevational ranges. We recognized the middle elevational band (between 1000 and 3000m) in the Northwestern Andes region of Colombia and Ecuador as a focal point for the origin and radiation of Pristimantis species. Additionally, we found several Andean migrations toward new habitats in Central Andes and Merida Andes for some species groups. We suggest that the paleogeological changes in the Northwestern Andes were the main promoter of speciation in Pristimantis, and may have served as a corridor for the dispersion of lowland species.

The multigenerational effects of water contamination and endocrine disrupting chemicals on the fitness of Drosophila melanogaster

Insect species can respond adaptively to stress temperature conditions including both thermal limits and reaction norms. In this study, we considered two populations of the whitefly Bemisia tabaci (Gennadius), in which adaptive differentiation was detected for tolerance to upper thermal limits. These two populations are found in two regions of Colombia with climatic differences: the Caribbean region with high environmental temperatures and the Southwest region with lower temperature regimens. We assessed the thermal responses to a range of 1 h heat shocks (37, 39, 41, 43 and 44 °C) performed below the thermal limits for this species. Thermal responses were measured using three life-history traits involved in fitness: survival, fecundity and viability of the offspring after heat shocks. Survival or fecundity as a response to heat shocks did not differ among populations; however, there were significantly different responses for viability between populations. The Southwestern population showed higher viability responses to low heat shocks than the Caribbean population. This relationship suggests a potential trade-off, which appears to be associated with climatic regions. In addition, these results suggest that adaptation under thermal limits does not necessarily involve similar responses throughout the reaction norm. A potential ongoing evolutionary response is taking place through the thermal reaction norms for viability after the invasion by this pest in Colombia.

Population Genetic Structure of Neotropical Mangrove Species on the Colombian Pacific Coast: Avicennia germinans (Avicenniaceae)1

We evaluated the performance of amphibian epithelial mucosa as a non-destructive method for sampling DNA in four extraction protocols. We took tissue from 68 individuals of Eleutherodactylus johnstonei (Anura: Eleutherodactylidae) through a surface smear of each specimen with a sterile swab. DNA was extracted using the DNeasy extraction kit (Qiagen), Salting-out, Phenol–chloroform, and Chelex protocols. We compared the quality of the resulting DNA through amplification and sequencing of the 16S rRNA mitochondrial gene. Successful amplification was obtained from DNA isolated from two protocols (Salting out and the DNeasy kit). The resulting sequences corresponded to those registered in the GenBank for this species, demonstrating that epithelial mucosa it is a valuable alternative method for obtaining DNA in frogs.

Population Genetic Structure of Neotropical Mangrove Species on the Colombian Pacific Coast: Pelliciera rhizophorae (Pellicieraceae)1

Abstract Water pollution due to human activities produces sedimentation, excessive nutrients, and toxic chemicals, and this, in turn, has an effect on the normal endocrine functioning of living beings. Overall, water pollution may affect some components of the fitness of organisms (e.g., developmental time and fertility). Some toxic compounds found in polluted waters are known as endocrine disruptors (ED), and among these are nonhalogenated phenolic chemicals such as bisphenol A and nonylphenol. To evaluate the effect of nonhalogenated phenolic chemicals on the endocrine system, we subjected two generations (F0 and F1) of Drosophila melanogaster to different concentrations of ED. Specifically, treatments involved wastewater, which had the highest level of ED (bisphenol A and nonylphenol) and treated wastewater from a constructed Heliconia psittacorum wetland with horizontal subsurface water flow (He); the treated wastewater was the treatment with the lowest level of ED. We evaluated the development time from egg to pupa and from pupa to adult as well as fertility. The results show that for individuals exposed to treated wastewater, the developmental time from egg to pupae was shorter in individuals of the F1 generation than in the F0 generation. Additionally, the time from pupae to adult was longer for flies growing in the H. psittacorum treated wastewater. Furthermore, fertility was lower in the F1 generation than in the F0 generation. Although different concentrations of bisphenol A and nonylphenol had no significant effect on the components of fitness of D. melanogaster (developmental time and fertility), there was a trend across generations, likely as a result of selection imposed on the flies. It is possible that the flies developed different strategies to avoid the effects of the various environmental stressors.