Browsing by Author "Torres Carvajal, Lenin Omar"
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Item Open Access A new cryptic species of Anolis lizard from northwestern South America (Iguanidae, Dactyloinae)(2018-11) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarA new species of Anolis lizard from the Andean slopes of southwestern Colombia and northwestern Ecuador, from between 1187 and 2353 m in elevation, is described. The new species can be distinguished from other Anolis in squamation, cranial osteology, hemipenial morphology, and nuclear and mitochondrial DNA. The new species is sister to Anolis aequatorialis, and it is suggested that previous records of A. aequatorialis in Colombia correspond to the new species described herein.Item Open Access A new giant anole (Squamata: Iguanidae: Dactyloinae) from southwestern Ecuador(2021) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarWe describe a new species of Anolis lizard from the Pacific slopes of the Andes of southwestern Ecuador at elevations between 372–1,000 m. The new species belongs to the Dactyloa clade and may be distinguished from other Anolis by size, external anatomy, mitochondrial DNA divergence, and dewlap color. Based on phylogenetic analyses of mitochondrial and nuclear DNA sequence data, we found that the new species is sister to A. fraseri in a clade composed primarily of large Dactyloid species. The new species is known from a protected area in southern Ecuador, Buenaventura Reserve, which suggests that at least some its populations are well protected.Item Open Access A new species of cat-eyed snake (Serpentes: Dipsadinae: Leptodeirini) from the Andes of southern Ecuador(2020) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarLeptodeira is one of the most widespread and taxonomically problematic snake taxa in the Americas. Here we describe a new species of Leptodeira from the Andes of southern Ecuador based on morphological and molecular data. The new species is geographically close and morphologically similar to L. ornata and L. larcorum, from which it can be distinguished by having smaller dorsal body blotches, a longer tail, and shorter spines on the hemipenial body. The shortest genetic distances between the new species and its congeners are 0.02 (16S), 0.05 (cytb), and 0.18 (ND4). The new species is restricted to the Jubones River Basin in southern Ecuador, an area of endemism for other reptile species. Our phylogenetic analysis based on mitochondrial and nuclear DNA sequence data also supports recognition of the names L. larcorum (restricted to Peru) for “L. septentrionalis larcorum”, and L. ornata for populations of “L. s. ornata” from central and eastern Panama, western Colombia, and western Ecuador. However, some samples of “L. s. ornata” from Panama and Costa Rica, as well as the new species described herein, are not included within or more closely related to L. ornata, which is sister to the clade (L. bakeri, L. ashmeadii).Item Open Access A new species of dactyloid anole (Iguanidae, Polychrotinae, Anolis) from the southeastern slopes of the Andes of Ecuador(2010) Torres Carvajal, Lenin Omar; Ayala-Varela, FernandoWe describe a new species of Anolis from the southeastern slopes of the Andes of Ecuador, province of Zamora-Chinchipe, Parque Nacional Podocarpus. It belongs to (1) the aequatorialis species-group by be- ing of moderate to large size with narrow toe lamellae, and (2) the eulaemus sub-group by having a typical Anolis digit, in which the distal lamellae of phalanx II distinctly overlap the proximal scales of phalanx I. The new species is most similar morphologically to A. fitchi but differs from it mainly by having a dewlap with longitudinal rows of 2−5 granular, minute scales separated by naked skin (longitudinal rows of one or two keeled, large scales separated by naked skin in A. fitchi) and a vertically shorter dewlap (longer dewlap in A. fitchi).Item Metadata only A Phylogenetic, Biogeographic, and Taxonomic study of all Extant Species of Anolis (Squamata; Iguanidae)(2017-11) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarAnolis lizards (anoles) are textbook study organisms in evolution and ecology. Although several topics in evolutionary biology have been elucidated by the study of anoles, progress in some areas has been hampered by limited phylogenetic information on this group. Here, we present a phylogenetic analysis of all 379 extant species of Anolis, with new phylogenetic data for 139 species including new DNA data for 101 species. We use the resulting estimates as a basis for defining anole clade names under the principles of phylogenetic nomenclature and to examine the biogeographic history of anoles. Our new taxonomic treatment achieves the supposed advantages of recent subdivisions of anoles that employed ranked Linnaean-based nomenclature while avoiding the pitfalls of those approaches regarding artificial constraints imposed by ranks. Our biogeographic analyses demonstrate complexity in the dispersal history of anoles, including multiple crossings of the Isthmusof Panama, two invasions of the Caribbean, single invasions to Jamaica and Cuba, and a single evolutionary dispersal from the Caribbean to the mainland that resulted in substantial anole diversity. Our comprehensive phylogenetic estimate of anoles should prove useful for rigorous testing of many comparative evolutionary hypotheses. [Anoles; biogeography; lizards; Neotropics; phylogeny; taxonomy]Item Open Access Alternative reproductive adaptations predict asymmetric responses to climate change in lizards(2019-03) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarAnthropogenic climate change ranks among the major global-scale threats to modern biodiversity. Extinction risks are known to increase via the interactions between rapid climatic alterations and environmentally-sensitive species traits that fail to adapt to those changes. Accumulating evidence reveals the influence of ecophysiological, ecological and phenological factors as drivers underlying demographic collapses that lead to population extinctions. However, the extent to which life-history traits influence population responses to climate change remains largely unexplored. The emerging ‘cul-de-sac hypothesis’ predicts that reptilian viviparity (‘live-bearing’ reproduction), a ‘key innovation’ facilitating historical invasions of cold climates, increases extinction risks under progressively warming climates compared to oviparous reproduction – as warming advances polewards/mountainwards, historically cold-climates shrink, leading viviparous species to face demographic collapses. We present the first large-scale test of this prediction based on multiple lizard radiations and on future projections of climate-based ecological niche models. Viviparous species were found to experience stronger elevational range shifts (and potentially increased extinctions) in coming decades, compared to oviparous lizards. Therefore, our analyses support the hypothesis’s fundamental prediction that elevational shifts are more severe in viviparous species, and highlight the role that life-history adaptations play in the responses of biodiversity to ongoing climate change.Item Open Access Are lizards feeling the heat? A tale of ecology and evolution under two temperatures.(2013) Torres Carvajal, Lenin Omar; Meiri, ShaiAim: Temperature influences most components of animal ecology and life history – but what kind of temperature? Physiologists usually examine the influence of body temperatures, while biogeographers and macroecologists tend to focus on environmental temperatures. We aim to examine the relationship between these two measures, to determine the factors that affect lizard body temperatures and to test the effect of both temperature measures on lizard life history. Location: World-wide. Methods: We used a large (861 species) global dataset of lizard body temperatures, and the mean annual temperatures across their geographic ranges to examine the relationships between body and mean annual temperatures. We then examined factors influencing body temperatures, and tested for the influence of both on ecological and life-history traits while accounting for the influence of shared ancestry. Results: Body temperatures and mean annual temperatures are uncorrelated. However, accounting for activity time (nocturnal species have low body temperatures), use of space (fossorial and semi-aquatic species are ‘colder’), insularity (mainland species are ‘hotter’) and phylogeny, the two temperatures are positively correlated. High body temperatures are only associated with larger hatchlings and increased rates of biomass production. Annual temperatures are positively correlated with clutch frequency and annual longevity, and negatively correlated with clutch size, age at first reproduction and longevity. Main conclusions: Lizards with low body temperatures do not seem to have ‘slower’ life-history attributes than species with high body temperatures. The longer seasons prevalent in warm regions, and physiological processes that operate while lizards are inactive (but warm enough), make environmental temperatures better predictors of lizard life-history variation than body temperatures. This surprisingly greater effect of environmental temperatures on lizard life histories hints that global warming may have a profound influence on lizard ecology and evolution.Item Metadata only Avances recientes en la sistemática y biogeografía de las lagartijas andinas del Clado cercosaurinae (Squamata: Gymnophthalmidae)Torres Carvajal, Lenin OmarGymnophthalmidae es uno de los clados de lagartijas neotropicales más diversos. Su sistemática ha sido tradicionalmente complicada, en gran parte porque ciertos caracteres morfológicos convergentes han confundido su clasificación. Por otro lado, hay especies muy escasas en las colecciones y aún existen áreas geográficas poco exploradas. Desde la publicación de la primera filogenia molecular de Gymnophthalmidae en el 2001, han existido importantes contribuciones que han ayudado a aclarar la sistemática y biogeografía de las más de 250 especies que componen este clado. Solamente en el Ecuador, donde se han registrado 51 especies de gimnoftálmidos, se han descrito seis especies (12%) en los últimos seis años. A nivel regional se han realizado cambios taxonómicos significativos. En esta ponencia presento las contribuciones recientes más importantes con énfasis en taxones presentes en los Andes del Ecuador.Item Metadata only Biología térmica de dos especies de lagartijas tropicales de los Andes ecuatorianos y su vulnerabilidad al cambio climáticoMerino Viteri, Andrés Ricardo; Torres Carvajal, Lenin OmarEste estudio analizó datos termofisiológicos y ambientales en tres poblaciones de lagartijas de dos especies cercanamente emparentadas, que habitan zonas altas de los Andes ecuatorianos, Stenocercus guentheri y Stenocercus festae. Se obtuvieron los valores de temperatura de preferencia (Tpref), temperatura corporal (Tb) y temperaturas críticas máxima (CTmax) y mínima (CTmin) de cada una de las poblaciones, y se compararon usando la prueba de Kruskal-Wallis. La variabilidad climática de cada sitio de estudio, podría actuar como una fuerza evolutiva sobre rasgos fisiológicos específicos, por esta razón existen diferencias estadísticamente significativas entre estas poblaciones. La temperatura del aire (Tair) registrada para cada sitio de estudio, así como las temperaturas operativas máximas y mínimas por hora (Te) de cada población sugieren que estas lagartijas tienen una gran disponibilidad de microambientes térmicos; por lo tanto, no muestran una restricción térmica para realizar sus actividades diarias, ya que pueden termorregular conductualmente. Además, los resultados del análisis de tolerancia al calentamiento muestran que las tres poblaciones presentan un amplio set de temperaturas en su entorno que podrían ser explotadas y así disminuir los posibles efectos negativos del cambio climático.Item Open Access Comparación morfológica de las lagartijas A. festae y A. nigrolineatus (Squamata: Iguanidae) del occidente del Ecuador(PUCE - Quito, 2023-06-19) Gudiño Negrete, María Emilia; Torres Carvajal, Lenin OmarEspecies del género Anolis son abundantes en el Ecuador; investigadores extranjeros y nacionales han ayudado a la identificación de algunas de sus especies. Antecedentes como la distribución, morfología, ecología, historia natural, datos moleculares, entre otros, son relevantes para el estudio de nuevas especies. En el presente trabajo se analizó la morfología de dos especies pertenecientes a la zona occidental del país; en la zona norte, Anolis festae y en la zona sur, A. nigrolineatus. El estudio surgió por la similitud en su morfología, priorizada por la coloración de su pliegue gular y la distribución de ambas especies. Se realizaron análisis estadísticos para visualizar diferencias morfológicas y merísticas. Durante el proceso de investigación se observó un patrón de coloración diferente en el iris de especímenes de una provincia del norte del país, por lo cual se incrementó otra hipótesis dentro del estudio. Los resultados sugieren que las especies no muestran diferencias significativas y se propone realizar análisis moleculares para aclarar su estatus taxonómico. Estudios similares han sugerido la existencia de especies crípticas.Item Metadata only Comparative evolution of an archetypal adaptive radiation: innovation and opportunity in anolis lizards(2018) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarAdaptive radiation is a widely recognized pattern of evolution wherein substantial phenotypic change accompanies rapid speciation. Adaptive radiation may be triggered by environmental opportunities resulting from dispersal to new areas or via the evolution of traits, called key innovations, that allow for invasion of new niches. Species sampling is a known source of bias in many comparative analyses, yet classic adaptive radiations have not been studied comparatively with comprehensively sampled phylogenies. In this study, we use unprecedented comprehensive phylogenetic sampling of Anolis lizard species to examine comparative evolution in this well-studied adaptive radiation. We compare adaptive radiation models within Anolis and in the Anolis clade and a potential sister lineage, the Corytophanidae. We find evidence for island (i.e., opportunity) effects and no evidence for trait (i.e., key innovation) effects causing accelerated body size evolution within Anolis. However, island effects are scale dependent: when Anolis and Corytophanidae are analyzed together, no island effect is evident. We find no evidence for an island effect on speciation rate and tenuous evidence for greater speciation rate due to trait effects. These results suggest the need for precision in treatments of classic adaptive radiations such as Anolis and further refinement of the concept of adaptive radiation.Item Metadata only Connectivity, population structure, and conservation of Ecuadorian green sea turtles(2017) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarStudies of highly migratory species that increase our understanding of the dynamics of genetic diversity, migratory routes, and genetic connectivity are essential for informing conservation actions. Genetic data for green turtles Chelonia mydas from Ecuador have only been available from Galápagos Islands (GPS) rookeries, but not from foraging aggregations. Furthermore, green turtles from habitats associated with mainland Ecuador (Machalilla National Park; MNP) have not been sampled. To assess the genetic relationships between nesting and foraging aggregations from these 2 regions and other regional populations, the mitochondrial DNA (mtDNA) control region was sequenced from 133 turtles. Conventional FST (haplotype frequency) and ΦST (sequence-based) values were low and non-significant between Ecuadorian rookeries, suggesting high connectivity between these sites located ca. 1000 km apart. Mixed stock analysis (MSA) indicated a dominant (>94%) GPS-MNP contribution to both foraging grounds, with small and nearly negligible contributions from other rookeries in the region (e.g. Costa Rica and Mexico). While orphan haplotypes were not included in the MSA because their rookery of origin is not known, their close genetic relationships to Western and Central Pacific mtDNA clades suggests that a relatively large percentage of turtles at the combined foraging sites (>10%) have been involved in transoceanic migration events. The genetic links between GPS and MNP C. mydas nesting populations revealed by our study highlight the need to incorporate the nesting populations from coastal Ecuador in more comprehensive future conservation planning.Item Open Access Cost-effectiveness of using small vertebrates as indicators of disturbance.(2014) Torres Carvajal, Lenin Omar; Mika, Robert PeckEn los bosques tropicales con gran riqueza de especies, el manejo efectivo de la biodiversidad exige medidas del progreso, sin embargo las limitaciones presupuestales típicamente restringen la capacidad de quienes toman las decisiones para evaluar la respuesta de las comunidades biológicas al cambio. Una estrategia consiste en identificar a las especies indicadoras de perturbaciones ecológicas (EIPE) cuyo monitoreo también es rentable. Estas especies pueden identificarse al determinar las respuestas individuales de las especies a las perturbaciones a lo largo de un gradiente; sin embargo, dichas respuestas pueden ser frustradas por otros factores que no son la perturbación. Por ejemplo, en los ambientes montañosos los efectos de la alteración antropogénica de hábitat son comúnmente frustrados por la elevación. Las especies indicadoras de perturbaciones ecológicas se han identificado con la medida del valor indicador (IndVal, en inglés), pero hay debilidades en la aplicación de esta estrategia en los sistemas montañosos complejos. Censamos aves, mamíferos pequeños, murciélagos y lagartijas de hojarasca en bosques de niebla con diferentes perturbaciones en los Andes Ecuatorianos. Después usamos la elevación en modelos (mixtos) lineales generalizados (M(M)LG) para buscar EIPE en el juego de datos. Finalmente usamos la rarefacción de datos de acumulación de especies para comparar los costos monetarios relativos de la identificación y monitoreo de EIPE en un esfuerzo igual de muestreo, basado en la riqueza de especies. Nuestro M(M)LG generó un mayor número de EIPE, pero un menor número de especies características con relación al IndVal. En términos absolutos, las aves fueron el más rentable de los cuatro taxones censados. Encontramos un ave que fuera rentable y que funcionara como EIPE. En términos del número de indicadores generados como una proporción de la riqueza de especies, las EIPE que fueron mamíferos pequeños también fueron las más rentables. Nuestra estrategia tiene el potencial de ser una herramienta útil para facilitar un manejo más sustentable de los sistemas boscosos en los Andes.Item Open Access Densidad, estructura poblacional y dieta de Rhinoclemmys nasuta (Testudines: Cryptodira) en la reserva Río Canandé, noroccidente ecuatoriano(PUCE, 2015) Calero Herrera, Wilson Andrés; Torres Carvajal, Lenin OmarUno de los taxones más antiguos y relevantes dentro del grupo de los reptiles vivientes es Testudines (Tortugas). Este linaje se originó hace aproximadamente 220 millones de años. El Turtle Taxonomy Working Group (2014) y el Turtle Conservation Coalition (2014), actualmente reconoce 335 especies de tortugas, de las cuales en Ecuador se han reconocido 31. Dentro de éstas, la Tortuga de Río Chocoana (Rhinoclemmys nasuta) considerada endémica del Chocó Biogeográfico, se encuentra casi amenazada (NT) mundialmente debido principalmente a la deficiencia de datos ecológicos y a la degradación de su hábitat. En base a esto, se realizó una investigación para conocer la densidad poblacional, estructura y dieta de una población dentro de la reserva Río Canandé. La densidad poblacional estimada fue de 4.6 individuos por hectárea; de estos, los juveniles fueron el estadio con 68.75 % de presencia del total de registros. En esta localidad la proporción de sexos fue dominada por hembras; sin embargo, eso se debe a que en los juveniles no es posible determinar el sexo, ya que carecen de caracteres sexuales secundarios. Utilizando el programa Mark (6.1) se estimó los valores teóricos para la población estudiada teniendo en cuenta misma probabilidad de supervivencia, esfuerzo de muestreo realizado, tasa de reclutamiento, migración e inmigración, lo que dio como resultado entre 32 a 42 individuos. Además, un total de 34 ítems alimenticios fueron identificados en las 24 muestras fecales de Rhinoclemmys nasuta donde del volumen total de ítems analizados el mayor aporte fue de las monocotiledóneas (%V= 91.755); dentro de la categoría de insectos o restos animales los ítems con mayor presencia en cuanto al volumen total fueron Aracnidae (%V=2.385) e Hymenoptera (%V= 1.3203); sin embargo, cuando se analizó por estadios reproductivos los ítems más representativos fueron las dicotiledóneas (%Fo= 202.857) y las mocotiledóneas (%Fo= 200) tanto en adultos como en juveniles. El solapamiento del nicho pudo ser comprobado gracias al alto valor obtenido para el índice de Morisita (CH= 0,92), lo que nos demuestra que tanto adultos como juveniles están utilizando los mismos lugares de forraje, por lo que no se pudo observar diferencia en cuanto a los ítems consumidos por Rhinoclemmys nasuta. La densidad y estructura poblacional nos ayuda a entender cómo funciona una población de tortugas dulceacuícolas, ya que nos permite tener un número determinado de individuos y sexos dentro de un área específica y sobre todo entender la estructura jerárquica dentro de un ecosistema lacustre. La mezcla de ítems alimenticios en la dieta de las tortugas dulceacuícolas ha probado ser uno de los factores más importantes para poder explicar las relaciones ecológicas entre las especies y sus ecosistemas. Por lo que estudios como el realizado en la Reserva Rió Canandé son importantes para conocer el estado de las poblaciones de tortugas continentales.Item Metadata only Description and Phylogeny of a New Species of Andean Lizard (Gymnophthalmidae: Cercosaurinae) from the Huancabamba Depression(2020) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarWe describe a new species of Macropholidus lizard from the Andean highlands of southern Ecuador and northern Peru based on recent collections. Among other characters, the new species differs from other species of Macropholidus in having a paired series of enlarged middorsal scale rows restricted to the nape, striated dorsal scales, as well as ocelli on tail, flanks, scapular region and neck. We also present a molecular phylogeny of Cercosaurinae and genetic distances as additional evidence supporting delimitation of the new species, which is sister to M. annectens from southern Ecuador. Data on Andean orogeny and age estimates of cercosaurine lizards suggest that the Huancabamba Depression, long recognized for its dual role as a biogeographic barrier and a migration corridor, has also served as a center of origin and diversification of Macropholidus lizardsItem Metadata only Description and phylogeny of three new species of Synophis (Colubridae, Dipsadinae) from the tropical Andes in Ecuador and Perú(2015-12) Torres Carvajal, Lenin OmarThe discovery of three new species of Synophis snakes from the eastern slopes of the tropical Andes in Ecuador and Peru is reported. All previous records of S. bicolor from eastern Ecuador correspond to S. bogerti sp. n., which occurs between 1000–1750 m along a large part of the Amazonian slopes of the Ecuadorian Andes. In contrast, Synophis zamora sp. n. is restricted to southeastern Ecuador, including Cordillera del Cóndor, between 1543–1843 m. Synophis insulomontanus sp. n. is from the eastern slopes of the Andes in central and northern Peru, between 1122–1798 m, and represents the first record of Synophis from this country. All three new species share in common a large lateral spine at the base of the hemipenial body. A molecular phylogenetic tree based on three mitochondrial genes is presented, including samples of Diaphorolepis wagneri. Our tree strongly supports Synophis and Diaphorolepis as sister taxa, as well as monophyly of the three new species described here and S. calamitus. Inclusion of Synophis and Diaphorolepis within Dipsadinae as sister to a clade containing Imantodes, Dipsas, Ninia, Hypsiglena and Pseudoleptodeira is also supported.Item Metadata only El descubrimiento de dos especies nuevas de Anolis (Iguanidae,Dactyloinae) en los Andes del sur de Ecuador, que llenan vacíos filogenéticosTorres Carvajal, Lenin OmarEn los últimos diez años, el Ecuador ha incrementado la diversidad de lagartijas del género Anolisa 38 especies. Se han descrito cinco especies nuevas, tres nuevos registros de distribución han sido reportados y el redescubrimiento a los 44 años de una especie que se creía extinta. En este trabajo se describen dos especies nuevas de lagartijas Anolisque son simpátricas de las estribaciones orientales de los Andes del sur de Ecuador, entre los 1440–1970 m de altitud. Las especies nuevas se diferencian de otros Anolispor su anatomía externa, color del pliegue gular y divergencia genética. También se estimó la posición filogenética de las especies nuevas usando un análisis Bayesiano de secuencias de ADN, incluyendo todas las especies disponibles del clado Dactyloa. Anolis hyacintogularissp. nov. es el taxón hermano de A. calimae(Colombia), mientras queA. lososisp. nov. es la especie hermana de A. williamsmittermeierorum(Perú). Las especies nuevas fueron recolectadas en el Parque Nacional Podocarpus, lo cual sugiere que al menos algunas poblaciones están protegidas.Item Metadata only Divergence of tropical pitvipers promoted by independent colonization events of dry montane Andean habitats(2019) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarAIM: A poorly explored feature of the origin and maintenance of Neotropical biodiversity is how the evolutionary dynamics of colonization and differentiation in relation to lowland and highland habitats has impacted lineage formation. Most speciation models for this region have focused on vicariant events, whereas the need to assess the influence of demographic processes has been recognized only recently. We evaluate if the origin of Andean montane lineages of terciopelo pitvipers is explained by either of two historical processes that represent distinct phylogeographic mechanisms: differentiation by isolation within the highlands or different dispersal events from the lowlands. LOCATION: Western Ecuador. TAXON: Terciopelo pitvipers (Bothrops asper species complex). METHODS: We use genomic data and genetic clustering analyses, evaluation of historical migration between genetic clusters and demographic model selection to investigate recent diversification events in South America using a vertebrate group rarely explored in phylogeographic studies: tropical Andean snakes. Specifically, the origin of two Ecuadorian montane lineages of terciopelo pitvipers was evaluated given ambiguous phylogenetic relationships with the presumably ancestral Pacific lowland lineage. RESULTS: Discrepancies of evolutionary relationships previously obtained with tree‐like methods are resolved through the use of modelling approaches. We found strong support for the independent orig in of montane lineages based on topologies inferred by maximum‐likelihood trees and modelling approaches that take into account possible gene flow. This suggests dispersal rather than in‐situ differentiation as the most likely mechanism by which the montane linages originated. MAIN CONCLUSIONS: Recent large‐scale studies have found support for identifying dispersal events as important drivers of diversification in the Neotropical region. We contribute to these ideas by identifying a fine‐scale case in a rarely studied group of animals ‐Andean snakes‐ in which river valleys acted as an entrance for the upward colonization of montane dry habitats and subsequent ecological diversification.Item Metadata only Diversity, threat, and conservation of reptiles from continental Ecuador(2017-12) Torres Carvajal, Lenin Omar; Torres Carvajal, Lenin OmarEcuador is one of the most reptile-diverse countries in the world, with 464 currently recognized species. Similar to other taxa, reptiles in Ecuador face important conservation challenges because of anthropogenic activities. Using distribution data of nearly 90% of the species of reptiles from continental Ecuador, as well as information on ecosystem protection status and anthropogenic activities, we present the first comprehensive quantitative study of reptile conservation in Ecuador. While species richness is higher in northwestern Ecuador and the central-northern Amazon, the conservation priority areas identified in this study also include the central Pacific coast, southwestern Ecuador, and the central-southern Amazon. Similar areas have been identified by previous studies as conservation gaps. Thus, our study reinforces the idea of protecting those areas to improve the conservation of biodiversity in continental Ecuador.Item Open Access Early bursts of body size and shape evolution are rare in comparative data(2010) Torres Carvajal, Lenin Omar; Harmon, Luke., LososGeorge Gaylord Simpson famously postulated that much of life’s diversity originated as adaptive radiations—more or less simulta- neous divergences of numerous lines from a single ancestral adaptive type. However, identifying adaptive radiations has proven difficult due to a lack of broad-scale comparative datasets. Here, we use phylogenetic comparative data on body size and shape in a diversity of animal clades to test a key model of adaptive radiation, in which initially rapid morphological evolution is followed by relative stasis. We compared the fit of this model to both single selective peak and random walk models. We found little support for the early-burst model of adaptive radiation, whereas both other models, particularly that of selective peaks, were commonly supported. In addition, we found that the net rate of morphological evolution varied inversely with clade age. The youngest clades appear to evolve most rapidly because long-term change typically does not attain the amount of divergence predicted from rates measured over short time scales. Across our entire analysis, the dominant pattern was one of constraints shaping evolution continually through time rather than rapid evolution followed by stasis. We suggest that the classical model of adaptive radiation, where morphological evolution is initially rapid and slows through time, may be rare in comparative data.