Publicaciones álvaro Rodrigo Barragán Yánez

Breve Historia De La Colaboración Entre La Fiscalía General Del Estado Y La Pontificia Universidad Católica Del Ecuador.
REVISTA
REVISTA ECUATORIANA DE MEDICINA Y CIENCIAS BIOLÓGICAS

Publicación
2015-06-01
La entomología forense permite esclarecer los hechos y determinar responsabilidades en casos de homicidios, suicidios, abandono y negligencia. Además, la entomología forense nos ayuda a valorar (de manera cuantitativa y cualitativa) la presencia de sustancias tóxicas en el cuerpo del fallecido, así como evidenciar el posible traslado de cadáveres. El desarrollo de esta ciencia se basa en la generación de información científica, la cual es interpretada por expertos en el tema para ser utilizada como evidencia ante las cortes. La puesta en práctica de procedimientos simples y eficaces va a determinar la correcta utilización de muestras entomológicas, integrando a esta disciplina en la cadena criminalística. En la presente nota se exponen los distintos avances y metas obtenidas tanto en la generación de información científica, como en las capacitaciones e intercambio de conocimientos entre el grupo de investigadores, el Área de entomología forense de la PUCE y los funcionarios de la FGE.

Climate Warming Effects In The Tropical Andes: First Evidence For Upslope Shifts Of Carabidae (Coleoptera) In Ecuador.
REVISTA
INSECT CONSERVATION AND DIVERSITY

Publicación
2016-04-29
1. In order to assess the impact of global warming on the biodiversity of the tropical high Andean paramo ecosystem, we compared historical and recent surveys of ground beetle communities along elevational gradients of the Pichincha volcano (Northern Ecuador). The studied datasets date to 1880, 1985/86 and 2013/15. 2. From 1880 to 1985, the bottom range of at least one stenotopic and wingless high-altitude species, Dyscolus diopsis, has shifted approximately 300 m upward, with the resulting area reduction of more than 90% from >12 km2 to <1 km2, which highlights the probability of future local extinctions on the Pichincha as well as on other mountains of Ecuador. 3. Over a shorter period of time, the comparison of the 1985/86 and 2013/14 datasets indicates that the lower limit of the superparamo ground beetle community has shifted upwards from circa 4300 m to circa 4400 m. Different individual responses are recorded among the species. Some of them did not experience any significant change, whereas the upper limit of one of the grassland generalists has shifted upwards at least 400 m in 28 years. 4. These results suggest that the response to global warming varies from one species to the other, depending on their degree of specialisation and tolerance. They call for the implementation of a monitoring programme that would use carabid assemblages as an indicator of the impact of climate change on the paramo ecosystem, in combination with other proxies.

Datos Preliminares De La Entomofauna Cadavérica En La Provincia De Pichincha - Ecuador.
REVISTA
REVISTA ECUATORIANA DE MEDICINA Y CIENCIAS BIOLÓGICAS

Publicación
2015-06-01
Se conoce muy poco sobre las especies (su taxonomía y biogeografía) que interactúan en el proceso de descomposición de cadáveres en el Ecuador. Aquí presentamos los primeros datos de la entomofauna cadavérica, en especial moscas y coleópteros (Insecta: Diptera, y Coleoptera) presente en Pichincha, Ecuador. Para lograr el objetivo, se usaron cobayos como cebo en tres diferentes lugares: Nayón, Quito y Otongachi. Los cobayos sacrificados fueron colocados en jaulas metálicas por 30 días, donde se obtuvo un total de 41 especies para los tres sitios de muestreo. La composición de especies varía según el lugar debido a las condiciones específicas que ofrece cada lugar como son la vegetación, las condiciones meteorológicas y el tipo de suelo.

Evidencias Entomológicas Al Servicio De La Justicia: Protocolo De Actuación Enmarcado A La Legislación De Ecuador
REVISTA
REVISTA ECUATORIANA DE MEDICINA Y CIENCIAS BIOLÓGICAS

Publicación
2020-11-30
El trabajo interdisciplinario de ciencias como criminalística de campo, medicina legal, biología forense, entomología forense, permiten lograr una investigación técnico-científica más objetiva y eficaz al momento de analizar un hecho delictivo. El presente trabajo se enfoca en la labor de la entomología forense en la investigación de un proceso judicial abarcando sus técnicas de actuación, manejo de muestras entomológicas (e.g., colección, preservación y almacenaje), y normas jurídicas del Ecuador en las que el personal encargado debe regirse para que las evidencias sean auténticas, legales y científicamente válidas. Es por ello que el presente estudio, expone los principales lineamientos del análisis de muestras entomológicas para una correcta labor forense.

Multi‐Taxa Colonisation Along The Foreland Of A Vanishing Equatorial Glacier
REVISTA
ECOGRAPHY

Publicación
2021-05-06
Retreating glaciers, icons of climate change, release new potential habitats for both aquatic and terrestrial organisms. High-elevation species are threatened by tempera-ture increases and the upward migration of lowlands species. Improving our under-standing of successional processes after glacier retreat becomes urgent, especially in the tropics, where glacier shrinkage is particularly fast. We examined the successional pat-terns of aquatic invertebrates, ground beetles, terrestrial plants, soil eukaryotes (algae,invertebrates, plants) in an equatorial glacier foreland (Carihuairazo, Ecuador). Basedon both taxonomical identification and eDNA metabarcoding, we analysed the effects of both environmental conditions and age of deglacierization on community composi-tion. Except for algae, diversity increased with time since deglacierization, especially among passive dispersers, suggesting that dispersal was a key driver structuring theglacier foreland succession. Spatial β-diversity was mainly attributed to enestedness for aquatic invertebrates, terrestrial plants and soil algae, likely linked to low environmen-tal variability within the studied glacier foreland; and to turnover for soil invertebrates, suggesting competition exclusion at the oldest successional stage. Pioneer communi-ties were dominated by species exhibiting flexible feeding strategies and high dispersalability (mainly transported by wind), probably colonising from lower altitudes, or from the glacier in the case of algae. Overall, glacier foreland colonisation in the trop-ics exhibit common characteristics to higher latitudes. High-elevation species are nev-ertheless threatened, as the imminent extinction of many tropical glaciers will affect species associated to glacier-influenced habitats but also prevent cold-adapted and hygrophilous species from using these habitats as refuges in a warming world.

Life Cycle Of Lucilia Sericata (Meigen 1826) Collected From Andean Mountains
REVISTA
NEOTROPICAL BIODIVERSITY

Publicación
2019-01-01
In forensic science, fly larval size and developmental time help to estimate the time elapsed since a person has died until the body is found, generally known as minimum postmortem interval (mPMI). Lucilia sericata (Meigen 1826) is a cosmopolitan and necrophagous fly species (Diptera: Calliphoridae) that usually colonizes decomposing stages. In this study, we determined life tables parameters of L. sericata (e.g. fly survivorship, mortality and life expectancy) and developmental time of different larval stages under controlled temperatures. Cohorts of 12 eggs (12 x 10 repetitions) of L. sericata were exposed to 8°C, 10°C, 18°C, 25°C, 30°C, 35°C, and 37 ± 0.5°C. We found that larval development was not complete at 8°C and 10°C (minimum temperature limit), and at 35°C and 37°C (maximum temperature limit). The number of larvae that reached the adult stage was similar (F2,30 = 0.20, p = 0.814) at all viable temperatures (18°C, 25°C, and 30°C). We found the highest mortality to occur at initial developmental stages. Under viable temperatures, the developmental time of L. sericata from egg to adult decreases with temperature, with an average of 778 h at 18°C, 401 h at 25°C, and 288 h at 30°C. The developmental time of L. sericata at the fastest temperature (778 h) is similar to that found in Vienna (Austria), but it is 2–3 times slower than that in three cities across the United States. These results will improve the estimation of mPMIs in tropical countries across the Andes region

First Records Of Diptera Associated With Human Corpses In Ecuador
REVISTA
NEOTROPICAL BIODIVERSITY

Publicación
2020-11-08
Flies in the order Diptera are of forensic value because many species leave tractable evidence while harvesting nutrients from decomposing corpses. From December 2015 to January 2017, 41 fly specimens were collected in human bodies at crime scenes and autopsies across the south of Ecuador. Six species, e.g., Chrysomya albiceps (Widemann 1819), Chrysomya megacephala (Fabricius, 1794), Synthesiomyia nudiseta (Wulp, 1883), Lucilia purpurascens (Walker,1836), Hemilucilia segmentaria (Fabricius, 1805), and Stomoxys calcitrans (Linneo, 1758) were identified to species level using morphological (dichotomous keys) and molecular (mitochondrial COI barcodes) techniques. One additional specimen remains unidentified to species level, but COI barcodes assigned it to the genus Paralucilia. These first taxonomically curated records of flies in real cases constitute a tangible groundwork for the development of forensic entomology in Ecuador

Green Bottle Flies (Calliphoridae, Luciliinae) Of Ecuador: Geographic Distribution, Checklist And Dna Barcodes
REVISTA
NEOTROPICAL BIODIVERSITY

Publicación
2020-09-01
Green bottle flies (Diptera, Calliphoridae, Luciliinae) comprise a diverse and cosmopolitan taxon, known from at least 1,500 species. They have become crucial elements in forensic investigations, as they spend part of their life cycle in decaying remains. Here, we review the distribution of eleven Luciliinae species in Ecuador: the monotypic Blepharicnema and ten Lucilia species. We identified specimens using morphological characters. Additionally, we DNA barcoded 43 specimens from three species using 658bp segments of the standard Cytochrome Oxidase I (COI) mitochondrial gen. Molecular and morphological identifications presented high correspondence, suggesting COI barcodes are an efficient tool for the identification of these three green bottle flies species. Geographical records are biased towards the northern Andean region, particularly near to large urban settlements. We remark the value to applied forensic research of continuous sampling of necrophagous flies under a variety of habitats and crime conditions.