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Protected areas (PAs) are a foundational and essential strategy for reducing biodiversity loss. However, many PAs around the world exist on paper only; thus, while logging and habitat conversion may be banned in these areas, illegal activities often continue to cause alarming habitat destruction. In such cases, the presence of armed conflict may ultimately prevent incursions to a greater extent than the absence of conflict. Although there are several reports of habitat destruction following cessation of conflict, there has never been a systematic and quantitative "before-and-after-conflict" analysis of a large sample of PAs and surrounding areas. Here we report the results of such a study in Colombia, using an open-access global forest change dataset. By analysing 39 PAs over three years before and after Colombia's peace agreement with the Revolutionary Armed Forces of Colombia (FARC), we found a dramatic and highly significant increase in the deforestation rate for the majority of these areas and their buffer zones. We discuss the reasons behind such findings from the Colombian case, and debate some general conservation lessons applicable to other countries undergoing post-conflict transitions. [ABSTRACT FROM AUTHOR]

An important evolutionary question concerns whether one or many barriers are involved in the early stages of speciation. We examine pre- and post-zygotic reproductive barriers between two species of butterflies ( Heliconius erato chestertonii and H. e. venus) separated by a bimodal hybrid zone in the Cauca Valley, Colombia. We show that there is both strong pre- and post-mating reproductive isolation, together leading to a 98% reduction in gene flow between the species. Pre-mating isolation plays a primary role, contributing strongly to this isolation (87%), similar to previous examples in Heliconius. Post-mating isolation was also strong, with absence of Haldane’s rule, but an asymmetric reduction in fertility (< 11%) in inter-specific crosses depending on maternal genotype. In summary, this is one of the first examples of post-zygotic reproductive isolation playing a significant role in early stages of parapatric speciation in Heliconius and demonstrates the importance of multiple barriers to gene flow in the speciation process. [ABSTRACT FROM AUTHOR]

Hybrid zones are powerful natural systems to study evolutionary processes to gain an understanding of adaptation and speciation. In the Cauca Valley (Colombia), two butterfly races, Heliconius cydno cydnides and Heliconius cydno weymeri, meet and hybridize. We characterized this hybrid zone using a combination of mitochondrial DNA (mtDNA) sequences, amplified fragment length polymorphisms (AFLPs), microsatellites and sequences for nuclear loci within and outside of the genomic regions that cause differences in wing colour pattern. The hybrid zone is largely composed of individuals of mixed ancestry. However, there is strong genetic discontinuity between the hybridizing races in mtDNA and, to a lesser extent, in all nuclear markers surveyed. The mtDNA clustering of H. c. cydnides with the H. cydno race from the Magdalena Valley and H. c. weymeri with the H. cydno race from the pacific coast suggests that H. c. cydnides colonized the Cauca Valley from the north, whereas H. c. weymeri did so by crossing the Andes in the southern part, implying a secondary contact origin. Colonization of the valley by H. cydno was accompanied by mimicry shift. Strong ecological isolation, driven by locally adaptive differences in mimetic wing patterns, is playing an important role in maintaining the hybrid zone. However, selection on wing pattern alone is not sufficient to explain the genetic discontinuity observed. There is evidence for differences in male mating preference, but the contribution of additional barriers needs further investigation. Overall, our results support the idea that speciation is a cumulative process, where the combination of multiple isolation barriers, combined with major phenotypic differences, facilitates population divergence in face of gene flow., (© 2012 Blackwell Publishing Ltd.)

Background: Cryptic population structure can be an indicator of incipient speciation or historical processes. We investigated a previously documented deep break in the mitochondrial haplotypes of Heliconius erato chestertonii to explore the possibility of cryptic speciation, and also the possible presence of endosymbiont bacteria that might drive mitochondrial population structure., Results: Among a sample of 315 individuals from 16 populations of western Colombia, two principal mtDNA clades were detected with 2.15% divergence and we confirmed this structure was weakly associated with geography. The first mtDNA clade included 87% of individuals from northern populations and was the sister group of H. erato members of Andes western, while the second clade contained most individuals from southern populations (78%), which shared haplotypes with an Ecuadorian race of H. erato. In contrast, analysis using AFLP markers showed H. e. chestertonii to be a genetically homogeneous species with no association between mitochondrial divergence and AFLP structure. The lack of congruence between molecular markers suggests that cryptic speciation is not a plausible explanation for the deep mitochondrial divergence in H. e chestertonii. We also carried out the first tests for the presence of endosymbiontic bacteria in Heliconius, and identified two distinct lineages of Wolbachia within H. e. chestertonii. However, neither of the principal mitochondrial clades of H. e. chestertonii was directly associated with the patterns of infection., Conclusions: We conclude that historical demographic processes are the most likely explanation for the high mitochondrial differentiation in H. e. chestertonii, perhaps due to gene flow between Cauca valley H. e. chestertonii and west Pacific slope populations of H. erato.

Introduction: Histoplasmosis, a fungal disorder characterized by a wide spectrum of manifestations that range from subclinical infections to disseminated processes, affects both immunocompetent and immunosuppressed individuals. Histoplasmosis is not a reportable disease in Colombia and consequently, a survey was designed to collect histoplasmosis cases diagnosed in the country., Objective: The aim of this work was to analyze the data collected from 1992 to 2008. Materials and methods. The survey included demographic data, risk factors, clinical manifestations, imaging data, diagnostic methods and antifungal treatment. Patients were grouped according to risk factors and comparisons of the various findings were done., Results: A total of 434 surveys were gathered from 20 of the country's Departments. Most patients (96.1%) were adults, 77% were males with a mean age of 38.4 years. Only 3.9% were children less than 15 years of age. In the adult population, AIDS was reported in 70.5% of the cases; additionally, in 7.0% patients other immunosuppressive conditions were informed. The most frequent clinical manifestations were fever (76.1%), cough (54.8%) and constitutional symptoms (56.8%). X rays abnormalities were represented mainly by infiltrates (65.9%) and nodules (17.1%). Diagnosis was made by microscopic observation of H. capsulatum in 49.6% patients, by culture in 58.0% and by serological test in 14.6% cases. Antifungal use was recorded in 52.5% cases., Conclusions: Histoplasmosis is frequent in Colombia, especially in certain risk factor groups such as the HIV-infected population. Data collected from this large number of cases has allowed valid comparisons on various aspects of histoplasmosis in Colombia.

Background: Sister species divergence and reproductive isolation commonly results from ecological adaptation. In mimetic Heliconius butterflies, shifts in colour pattern contribute to pre- and post-mating reproductive isolation and are commonly correlated with speciation. Closely related mimetic species are therefore not expected, as they should lack several important sources of reproductive isolation., Results: Here we present phenotypic, behavioral and genetic evidence for the coexistence of two sympatric 'cryptic' species near Florencia in the eastern Andes of Colombia that share the same orange rayed colour pattern. These represent H. melpomene malleti and a novel taxon in the H. cydno group, here designated as novel race of Heliconius timareta, Heliconius timareta florencia. No-choice mating experiments show that these sympatric forms have strong assortative mating ( approximately 96%) despite great similarity in colour pattern, implying enhanced divergence in pheromonal signals., Conclusion: We hypothesize that these species might have resulted from recent convergence in colour pattern, perhaps facilitated by hybrid introgression of wing pattern genes.

In Heliconius butterflies, it has been proposed that speciation occurs through a combination of divergence in ecological habitat preferences and mimetic colour patterns. Here we test this hypothesis by investigating a parapatric form of the widespread species Heliconius erato. Mendelian (colour patterns) and molecular genetic data permit us to address hypotheses about introgression and genetic differentiation between different populations. Combined analysis of colour pattern, microsatellite loci and mitochondrial DNA showed that Heliconius erato venus and Heliconius erato chestertonii form a bimodal hybrid zone implying partial reproductive isolation. In a sample of 121 individuals collected in sympatry, 25% were hybrids representing a significant deficit of heterozygotes compared to the Hardy-Weinberg expectation. Seven microsatellite loci, analysed for a subset of these individuals, showed marked differentiation between the parental taxa, and unambiguously identified two genotypic clusters concordant with our phenotypic classification of individuals. Mitochondrial DNA analysis showed H. erato venus as a monophyletic group well differentiated from H. erato chestertonii, implying a lack of historical introgression between the populations. Heliconius erato chestertonii is therefore an incipient species that maintains its integrity despite high levels of hybridization. Moreover, H. erato chestertonii is found at higher altitudes than other races of H. erato and has a distinct colour pattern and mimetic relationship. Hence, there are now two examples of parapatric incipient species related to H. erato, H. himera and H. erato chestertonii, both of which are associated with higher altitudes, more arid habitats and distinct mimetic relationships. This implies that parapatric habitat adaptation is a likely cause of speciation in this group.

Introduction: A national survey on cryptococcosis has been conducted in Colombia since 1997. The survey data recorded over a 9-year period, 1997 to 2005, was summarized., Materials and Methods: The format provided by the European Confederation of Medical Mycology was adapted with the correspondent permission., Results: Over the 9 year period, 931 surveys were received from 76 centers. The associated disease syndromes were as follows: 891 (95.7%) were neurocryptococosis cases, 27 (2.9%) pulmonary disease, 5 (0.5%) cutaneous lesions, 2 (0.2%) ganglionar forms, 2 (0.2%) oropharyngeal lesions and one case (0.1%) each from peritonitis, liver lesion, cellulitis and urinary tract infection. Demographic data indicated 82.7% of the subjects were males, and 59.4% were between 20-39 years old; 25 children less than 16 years old were reported. The prevalent risk factor was HIV infection (78.1%). The mean annual incidence rate of cryptococcosis in the general population was 2.4 X 106 inhabitants, but in AIDS patients the rate rose to one in 3 X 103. The most frequent clinical features were headache (85.2%), nausea and vomiting (59.1%), fever (59.0%), mental changes (46.2%), meningeal signs (33.4%), cough (23.6%) and visual alterations or loss of vision (20.9%). Laboratory data showed that direct examination of cerebrospinal fluid (CSF) was positive in 92.8% cases and Cryptococcus was recovered in 90.3% of the cases. Cryptococcal antigen reactivity was 98.9% in CSF and 93.7% in serum samples. From 788 isolates submitted, 95.9% were C. neoformans var. grubii serotype A, 0.3% var. neoformans serotype D, 3.3% C. gattii serotype B and 0.5% C. gattii serotype C. The majority of patients were treated initially with amphotericin B., Conclusion: Cryptococcosis incidence has increased dramatically in Colombia with the AIDS pandemic and it can be considered as a sentinel marker for HIV infection.

Speciation is generally regarded to result from the splitting of a single lineage. An alternative is hybrid speciation, considered to be extremely rare, in which two distinct lineages contribute genes to a daughter species. Here we show that a hybrid trait in an animal species can directly cause reproductive isolation. The butterfly species Heliconius heurippa is known to have an intermediate morphology and a hybrid genome, and we have recreated its intermediate wing colour and pattern through laboratory crosses between H. melpomene, H. cydno and their F1 hybrids. We then used mate preference experiments to show that the phenotype of H. heurippa reproductively isolates it from both parental species. There is strong assortative mating between all three species, and in H. heurippa the wing pattern and colour elements derived from H. melpomene and H. cydno are both critical for mate recognition by males.

Abstract Shared ancestral variation and introgression complicates the reconstruction of phylogenetic relationships among closely related taxa. Here we use overall genomic compatibility as an alternative estimate of species relationships in a group where divergence is rapid and genetic exchange is common. Heliconius heurippa, a butterfly species endemic to Colombia, has a colour pattern genetically intermediate between H. cydno and H. melpomene: its hindwing is nearly indistinguishable from that of H. melpomene and its forewing band is an intermediate phenotype between both species. This observation has lead to the suggestion that the pattern of H. heurippa arose through hybridization. We present a genetic analysis of hybrid compatibility in crosses between the three taxa. Heliconius heurippa x H. cydno and female H. melpomene x male H. heurippa yield fertile and viable F1 hybrids, but male H. melpomene x female H. heurippa crosses yield sterile F1 females. In contrast, Haldane's rule has previously been detected between H. melpomene and H cydno in both directions. Therefore, H. heurippa is most closely related to H. cydno, with some evidence for introgression of genes from H. melpomene. The results are compatible with the hypothesis of a hybrid origin for H. heurippa. In addition, backcrosses using F1 hybrid males provide evidence for a large Z(X)-chromosome effect on sterility and for recessive autosomal sterility factors as predicted by Dominance Theory.