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by DF Cisneros-Heredia
¡Porque en la diversidad está el gusto!
Conocimiento, ciencia, vida, conservación, comunicación, educación, libertad.
13 diciembre 2009
Rana de Cristal en Peligro Crítico de Extinción por pérdida de hábitat
11 diciembre 2009
Climategate: Anatomy of a Public Relations Disaster @Yale e360
Published by Fred Pearce at the blog Yale e360
Another Round With The CRU E-mails... by Bradford Plummer
A pesar de la masiva cantidad de evidencia de que el cambio climático, el calentamiento global y el efecto invernadero son realidad, y de que los humanos si hemos tenido efectos a diferentes niveles sobre estos factores, aún hay personas que intentan a como de lugar desacreditarlos. Lastimosamente, ahora último se están valiendo de un lamentablemente incidente con unos emails que se filtraron del grupo de estudio sobre cambio climatico de la Universidad de East Anglia. Sin embargo, e incluso si las interpretaciones de esos emails fueran válidas (que certeramente no lo son, sino mal intencionadas), East Anglia no es el único grupo que ha estudiado sobre el cambio climático, y existen miles de estudios, tanto climáticos, metereológicos, físicos, biológicos, y antropológicos que presentan pruebas irrefutables del impacto de los humanos.
Esta nueva campaña para desacreditar al impacto humano sobre el cambio climático esta efectivamente enfocada en personas que no saben (o presumen saber, pero deficientemente) sobre el proceso científico de estudio del cambio climático, sobre su complejidad, y sobre todo, sobre la gran cantidad de estudios reales que han sido publicados, cada uno de manera independiente. La ciencia es un proceso objetivo, donde la independencia y libertad de estudio son la clave, por lo tanto es ilógico e irracional pensar que los científicos del planeta entero, incluyendo investigadores latinoamericanos, todos se hayan confabulado en una gran y nueva "conspiración".
Traduciendo al Castellano el último párrafo de este artículo de Bradford Plummer:
"Si, los científicos del clima deberían hacer esfuerzos para ser lo más transparente posibles, y algunos de los emails CRU prueban lo contrario. Eso debe ser solucionado. Sin embargo, no hay evidencia de que los datos climáticos hayan sido manipulados, e incluso si hubiese algo torcido en los e-mails CRU, la base para lo que conocemos sobre el impacto humano en el cambio climático todavia proviene de una gran variedad de fuentes"
10 diciembre 2009
Consecuencias del Cambio Climático
“El Grupo Intergubernamental de Expertos sobre el Cambio Climático (IPPC) - un foro científico establecido en el marco de las Naciones Unidas en 1988 para reunir a miles de expertos en clima de todo el mundo - prevé que la temperatura global media ha sido influenciada por las actividades humanas en al menos 1°C y puede subir a lo largo de este siglo entre 1,4 y 5,8°C.”
09 diciembre 2009
Calentamiento global: los humanos tenemos mucho que ver!
"Calentamiento global es un término utilizado habitualmente para el fenómeno observado en las medidas de la temperatura que muestra en promedio un aumento en la temperatura de la atmósfera terrestre y de los océanos en las últimas décadas y también para describir a la teoría que predice, a partir de proyecciones basadas en simulaciones computacionales, un crecimiento futuro de las temperaturas."
08 diciembre 2009
¿Por qué ocurre el Cambio Climático?
“Algunos de los principales aspectos físicos involucrados en el cambio climático incluyen el sol, la órbita y variaciones del campo magnético de la tierra, y las corrientes oceánicas. La temperatura media de la Tierra depende del flujo de radiación solar que recibe. Factores como la cantidad de manchas de solares y la variación en los campos magnéticos del Sol tienen una fuerte acción sobre distintos componentes del clima como los fenómenos de El Niño y La Niña, y las corrientes polares. La órbita terrestre oscila periódicamente, haciendo que la radiación que recibe cada hemisferio fluctúe, provocando por ejemplo las eras glaciales. Las variaciones en el campo magnético terrestre también afectan el clima y se ha comprobado que en épocas pasadas hubo inversiones de polaridad. Los polos magnéticos si bien tienden a encontrarse próximos a los polos geográficos, en algunas ocasiones se han aproximado al Ecuador. Las corrientes oceánicas, o marinas, son un factor regulador del clima en especial influenciadas por diferencias en la temperatura y la salinidad.”
07 diciembre 2009
¿Qué es el Cambio Climático?
06 diciembre 2009
Corales de Galápagos: Investigaciones, Conservación y Cambio Climático
04 diciembre 2009
Preguntas Frecuentes sobre el VIH/SIDA
¿Puedo saber si una persona esta contagiada con VIH con solo verla?
No, el VIH puede no presentar síntomas. De hecho, se estima que 1 de cada 3 personas que tienen VIH no lo saben. La única manera de saberlo es a través de la prueba del VIH.
¿Puedo contraer el virus si le doy la mano, un abrazo o me rozo con alguien con VIH?
No, el VIH no es un virus que se adquiera fácilmente y no sobrevive fuera del cuerpo. NO puede ser transmitido a través de contacto casual o cotidiano. Dar la mano y abrazar son acciones que no transmiten el VIH; así como tampoco un estornudo, la picadura de un mosquito, compartir la vajilla o los mismos servicios higiénicos, la depilación con cera, la saliva, las lágrimas, el sudor, el aire, el agua, o los alimentos; ninguno transmite el VIH.
03 diciembre 2009
¡PROTEGETE! Aprende como se coloca un condón
VIH, SIDA y cómo saber si tengo
“El Estadío I incluye al período de la infección con VIH que es asintomático y por ende no es categorizado como SIDA. El Estadío 2 incluye manifestaciones menores mucocutáneas, es decir laceraciones en áreas como la parte interna de la boca y del ano e infecciones recurrentes del tracto respiratorio superior. El 3 incluye diarreas crónicas por períodos de más de un mes, infecciones bacterianas severes y tuberculosis pulmonar. En el Estadío 4 se observan masivas infecciones bacterianas y fúngicas como toxoplasmosis en el cerebro y candidiasis en el esofago, traquea y pulmones, así como el aparecimiento del sarcoma de Kaposi, un tipo de cáncer tumoral relacionado con el herpes."
02 diciembre 2009
¿Cómo se transmite el VIH?
01 diciembre 2009
Día Mundial del SIDA
30 noviembre 2009
¿Qué son el VIH y el SIDA?
27 noviembre 2009
Impacto de la evolución en nuestra sociedad
24 noviembre 2009
Seis pruebas fehacientes de la Evolución
23 noviembre 2009
15 Respuestas al Sin-sentido Creacionista por John Rennie
Artículo de John Rennie, Editor en Jefe de Scientific American, publicado en Inglés en la revista Scientific American de Julio 2002 (descargar AQUÍ la versión en Inglés). Traducción al Castellano basada en dos contribuciones en línea: 15 respuestas a las Estupideces Creacionistas y 15 respuestas al sin-sentido creacionista
Evolución, el proceso clave para la vida
Evolución es el proceso de cambio de las características y diversidad de vida sobre la Tierra a través del tiempo. Estos cambios se dan por variaciones en el material genético de las diferentes poblaciones de seres vivos a lo largo de diferentes generaciones. Los cambios se pueden producir en cualquier generación y se acumulan con el paso del tiempo, creando modificaciones que eventualmente culminan en la emergencia de nuevas especies.
12 noviembre 2009
Nueva lagartija descubierta en la Cordillera del Cóndor
La descripción de esta nueva especie fue publicada en la revista científica ZooKeys: Torres-Carvajal, O., de Queiroz, K. & Etheridge, R. (2009) A new species of iguanid lizard (Hoplocercinae, Enyalioides) from southern Ecuador with a key to eastern Ecuadorian Enyalioides. ZooKeys 27: 59–71
Pueden descargar esta publicación aquí: http://pensoftonline.net/zookeys/index.php/journal/article/view/273
Fotografía: Macho de Enyalioides rubrigularis, Omar Torres-Carvajal (Torres-Carvajal et al. 2009. ZooKeys 27).
09 noviembre 2009
Color, Danza y Sexo en la Naturaleza: Dragones y Colibríes
El Colibrí Maravilloso Cola de Espátula es una especie endémica de Perú considerada como una de las aves más raras del mundo. Restringido al valle del Río Utcubamba en el noreste de Perú, los machos de esta especie se caracterizan por poseer dos plumas en la cola que tienen forma de raqueta, se cruzan y terminan en dos discos espatulados de color azul violeta.
Debido a la pérdida de su hábitat y rango geográfico restringido, este colibrí es considerado en Peligro de Extinción.
El Dragón Marino es una de las dos especies de dragones marinos que viven en las costas de Australia; son parientes de los caballitos de mar. Estos peces confian en su camuflaje para esconderse de sus predadores y lucen elaborados y coloridos diseños.
Ventajosamente, los dragones marinos no son demandados por el mercado chino de medicina alternartiva (al contrario de los caballitos marinos) y sus poblaciones no han sufrido grandes disminuciones, pero de todas formas la destrucción de los ambientes marinos que habitan implica un alto riesgo para su supervivencia y han sido clasificados a nivel mundial como, Casi Amenazados de Extinción.
Fotografías: Colibrí: David Cook Wildlife Photography, disponible en flickr http://www.flickr.com/photos/kookr/3793738016/. Dragón Marino: Richard Ling, disponible en Wikimedia Commons http://commons.wikimedia.org/wiki/File:Phyllopteryx_taeniolatus1.jpg
08 noviembre 2009
Pristimantis metabates, nueva especie de rana para Ecuador
Pristimantis metabates es una especie de rana recientemente descrita en 1999 de una localidad en el noreste de Perú. La nueva localidad Ecuatoriana representa el segundo registro para la especie y el primero para Ecuador. Pristimantis skydmainos es una especie rara pero distribuida en algunas localidades en la Amazonía de Ecuador, Peru, Brasil y Bolivia. En Ecuador era conocida solamente de especimenes colectados en el Estación de Biodioversidad Tiputini, una estación de investigacion de campo manejada por la Universidad San Francisco de Quito, el registro en Zamora-Chinchipe representa la segunda localidad de esta especie en Ecuador.
Los nuevos registros de estas especies fueron realizados en el Centro de Estudios y Desarrollo para la Amazonía (CEDAMAZ), una reserva manejada por la Universidad Nacional de Loja; localizada a 68 km de la ciudad de Zamora (03.733° S, -78.6° W, 775–1150 m a.s.l.).
El artículo científico donde se publicaron estos datos es:
Cisneros-Heredia, D.F., Armijos-Ojeda, D. & Valarezo, K. (2009) First country record of Pristimantis metabates (Duellman and Pramuk) and distribution extension of Pristimantis skydmainos (Flores and Rodríguez) in eastern Ecuador (Amphibia, Anura, Strabomantidae). Herpetology Notes 2: 185–188.
Pueden descargar esta artículo en: http://www.cisneros-heredia.org/public.html
Fotografías: Superior: Pristimantis metabates; inferior: Pristimantis skydmainos. D. Armijos-Ojeda
28 septiembre 2009
Datos y conclusiones de una cumbre irrepetible: 2a CUMBRE MUNDIAL DE EVOLUCIÓN
2da Cumbre Mundial de Evolución
La Universidad San Francisco de Quito USFQ y su Instituto Académico de Galápagos para las Artes y las Ciencias (GAIAS) llevaron a cabo la “Segunda Cumbre Mundial de Evolución”. Este evento fue una cita científica sin precedentes, con más de 150 científicos y estudiantes de diferentes países del mundo.
Por segunda ocasión, la USFQ reunió a los científicos evolucionistas más importantes del mundo en las Islas Galápagos. Los invitados discutieron los últimos avances en investigaciones relacionados con el proceso natural que conduce el desarrollo de la vida desde sus orígenes: la Evolución.
19 septiembre 2009
New Glassfrog from northwestern Ecuador
This new species, named after Francisco Sornoza -Ecuadorian conservationist and ornithologist, is diagnosed by having a protruding snout in lateral profile, uniform green dorsal colouration in life, concealed prepollex, extensive webbing between the outer fingers, fully webbed toes, and small body size. It inhabits the Non-Seasonal Evergreen Foothill and Lowland forests in the provinces of Esmeraldas, Imbabura, and Pichincha, north-western Ecuador.
Several new records of different species previously unknown from Ecuador have been obtained in these foothill forests in northwestern Ecuador. Unfortunately, they are severely threatened by habitat destruction, which has already destroyed about 50% of the foothill forests in western Ecuador.
The description of the new Teratohyla sornozai was published in the scientific journal Zootaxa: Cisneros-Heredia, D.F., Yánez-Muñoz, M.Y. & Ortega-Andrade, H.M. (2009) Description of a new species of Teratohyla Taylor (Amphibia: Athesphatanura: Centrolenidae) from north-western Ecuador. Zootaxa 2227: 53–62.
Photo by H. M. Ortega-Andrade.
20 agosto 2009
Checking on Tasmanian Devils' Facebook to Save Them
The Tasmanian Devil (Sarcophilus harrisii) is the largest extant carnivorous marsupial. Its populations have suffered severe declines due to an infectious cancer, the devil facial tumour disease (DFTD). DFTD is an aggressive non-viral transmittable parasitic cancer. It produces facial tumors that interfere with feeding, and the affected animal starve to death. DFTD has ravaged Tasmania's wild devils, with declines up to 50% of the population.
Determining exactly how the animals interact could improve control efforts, but few studies have managed to reproduce social networks. Rodrigo K. Hamede and colleagues of the School of Zoology of the University of Tasmania, Australia, have just published in Ecology Letters their research on the structure of the contact network between individuals, a key factor on the transmission of infectious disease.
These researchers used a novel technology, proximity sensing radio collars, that detects when two animals came close to each other. These collars were fitted into 27 devils. Results indicate that all studied devils were connected in a single giant component. Since all animals are therefore connected directly or indirectly to every other animal, diseases would easily spread throughout the network from any single infected individual. More male-female contact occurred during mating season, while females interacted more frequently with females during non-mating periods.
These results suggest that there is limited potential to control the disease by targeting highly connected age or sex classes. The team was unable to find one sex or age group that had more connections than others. That information might have allowed control programs to stanch the spread of disease by targeting the most connected class.
Photographs: Wikipedia & author
Access the scientific article: Hamede, R.K. et al. 2009. Contact networks in a wild Tasmanian devil (Sarcophilus harrisii) population: using social network analysis to reveal seasonal variability in social behaviour and its implications for transmission of devil facial tumour disease. Ecology Letters DOI: 10.1111/j.1461-0248.2009.01370.x
See Journal Watch Online Blog Entry: http://journalwatch.conservationmagazine.org/2009/08/20/ties-that-bite/
Revisando el Facebook de los Demonios de Tasmania para Salvarlos!
EL Demonio de Tasmania (Sarcophilus harrisii) es el mayor marsupial carnívoro viviente. Sus poblaciones han sufrido severas disminuciones debido a un cancer infeccioso, el tumor facial de los demonios (devil facial tumour disease, abreviado DFTD). El DFTD es un cancer parasítico transmisible no-viral muy agresivo. Produce tumores faciles que interfieren con la alimentación y los animales afectados mueren de hambre. El DFTD ha arrasado con los demonios de Tasmania, con disminuciones poblacionales de hasta 50%.
Determinar exactamente cómo los animales interactuan podría mejorar los esfuerzos de control, pero pocos estudios han podido reproducir las redes sociales. Rodrigo K. Hamede y colegas de la Escuela de Zoología de la Universidad de Tasmania, Australia, han recientemente publicado en la revista científica Ecology Letters su estudio sobre la estructura de las redes de contacto entre individuos, un factor clave en la transmisión de enfermedades infecciosas.
Estos investigadores han usado una nueva técnología, collares de radio con sensores de proximidad que detectan cuando dos animales se acercan. Estos collares fueron colocados en 27 demonios. Los resultados indican que todos los demonios estudiados estuvieron conectados en un solo componente gigante. Dado que todos los animales están por lo tanto ligados directa o indirectamente entre sí, enfermedades podrían rapidamente extenderse dentro de la red desde cualquier individuo infectado. Mayor cantidad de contactos macho-hembra fueron observados durante la temporada de apareamiento, mientras que las hembras interactuaron más frecuentemente durante el resto del tiempo.
Estos resultados sugieren que hay un limitado potencial para controlar la enfermedad al enfocarse en clases sexuales o de edades altamente conectadas. El equipo no pudo encontrar un sexo o grupo de edad que tuvieren más conexiones que otro. Esta información hubiese podido permitir programas de control para bloquear la diseminación de la enfermedad al enfocarse en la clase más conectada.
Acceder al artículo científico:
Hamede, R.K. et al. 2009. Contact networks in a wild Tasmanian devil (Sarcophilus harrisii) population: using social network analysis to reveal seasonal variability in social behaviour and its implications for transmission of devil facial tumour disease. Ecology Letters DOI: 10.1111/j.1461-0248.2009.01370.x
Lea el blog Journal Watch Online de este artículo:http://journalwatch.conservationmagazine.org/2009/08/20/ties-that-bite/
18 agosto 2009
Galapagos Pink Iguana: A new species just described!
Darwin did not visit the volcano on his travels to the Ecuadorian Archipelago of Galapagos in the 1830s, and the Galapagos Pink Iguana was only first observed in 1986, when park rangers of the Galapagos National Park climbed Wolf Volcano and observed 5 pink iguanas with dark marks. Initially, they were thought to be some intra-population variation or even stained by some substance. But, when studies took body measurements and blood samples from 36 individuals, morphological and genetic analysis confirmed that they were an undescribed new species.
This new species differs in its morphology, behaviour, and genetics from the other two Galapagos Land Iguanas, Conolophus subcristatus and Conolophus pallidus, which are usually brown coloured.
Besides the taxonomic implications of this discovery, the Pink Iguana is extremely important as it is the only evidence of deep divergence within the Galápagos land iguana lineage. In fact, the new species carries an ancient evolutionary legacy, being the only remnant of a lineage originated when the Galápagos archipelago did not have its present geography and configuration.
This new species is endemic to the Wolf Volcano, the highest of the Galapagos. It is estimated than less than 200 adult individuals are alive. Feral cats introduced to the island may be eating the young reptiles and goats may be competitors for food. Thus, the Galapagos Pink Iguana is Critically Threated by Extinction.
The description of this new species was published by Gabriele Gentile of Università Tor Vergata (Roma, Italia) and Howard Snell of University of New Mexico (Albuquerque, USA) in the scientific journal Zootaxa of 18 August 2009.
Citation of the scientific article:
Gentile, G. & Snell, H. (2009) Conolophus marthae sp.nov. (Squamata, Iguanidae), a new species of land iguana from the Galápagos archipelago. Zootaxa, 2201, 1–10.
Download the PDF of the article: http://www.mapress.com/zootaxa/2009/f/zt02201p010.pdf
Potography: Gabrielle Gentile
Nueva Especie: Iguana Rosada de Galápagos Descrita como "Conolophus marthae"
La Iguana Rosada de Galápagos fue observada por primera vez en 1986 cuando oficiales del Parque Nacional Galápagos subieron al volcán Wolf y observaron 5 iguanas rosadas con marcas negras. Inicialmente pensaron que los individuos estaban manchados por alguna sustancia o que correspondian a alguna variación inter-poblacional. Sin embargo, cuando estudios posteriores tomaron datos corporales y muestras de sangre de 36 individuals, los análisis morfológicos y genéticos confirmaron que se trataba de una especie diferente y nunca antes reportada.
Esta nueva especie difiere en su morfología, compartamiento y génetica de las otras dos especies de Iguanas Terrestres de Galapagos, llamadas Conolophus subcristatus y Conolophus pallidus, que suelen ser de color café.
Además de las implicaciones taxonómicas de este descubrimiento, la Iguana Rosada es muy importante desde un punto de vista evolutivo pues representa la única evidencia de una profunda divergencia en el linaje de las Iguanas Terrestres de Galápagos. De hecho, la Iguana Rosada tiene un legado evolutivo tán antiguo que precede la actual geografía y configuración de las islas Galápagos.
Esta nueva especie habita únicamente en el Volcán Wolf, el más alto del archipelago. Se estima que existen en total menos de 200 individuos vivos, por lo que la Iguana Rosada de Galápagos es una especie en Crítico Peligro de Extinción.
La descripción de esta nueva especie fue publicada por Gabriele Gentile de la Università Tor Vergata (Roma, Italia) y por Howard Snell de la Universidad de Nuevo México (Albuquerque, USA) en la revista científica Zootaxa del 18 de Agosto 2009.
Cita del artículo científico:
Gentile, G. & Snell, H. (2009) Conolophus marthae sp.nov. (Squamata, Iguanidae), a new species of land iguana from the Galápagos archipelago. Zootaxa, 2201, 1–10.
Fotografía: Gabrielle Gentile
17 agosto 2009
Galapagos, Epicentre of the Second World Summit on Evolution
The World Summit on Evolution is the largest gathering of evolutionary scientists, each time with more than 150 participants. It has been called "The Woodstock of Evolution", bringing together experts and students from widely different areas of evolutionary biology that rarely have the chance to meet. Some of the world most-famous researchers working on evolution have participated, including Peter and Rosemary Grant, Niles Eldredge, Antonio Lazcano, Douglas Futuyma, Lynn Margulis, Ada Yonath, William H. Calvin, Daniel Dennett, among others.
Evolution is the natural process responsible for the huge diversity of life in our planet and has deep implications in all aspects of humanity. Evolutionary biology studies have been key factors for the development of novel source materials for the industry, for the prevention and control of infectious diseases, and for the design of new conservation strategies. The Galapagos Islands are not important just because of Darwin’s discoveries. An impressive amount of scientific studies have been developed over the years after his visit. As information increases on the flora and fauna of the islands and their ecological patterns, it is clear that the Galapagos are a living laboratory of evolution.
The goals of the summit are to join experts from different branches of evolutionary biology to discuss on the impacts of recent discoveries in order to integrate them inside the basic concepts of evolution. Also, to remind to the scientific community on the importance of the Galapagos Islands and the discoveries produced thanks to their particular natural resources. This summit will present the islands as a living and dynamic laboratory of evolution. And of course, promoting Ecuador, its researcher, and its academic institutions working to develop scientific knowledge.
The main subjects discussed during the Second World Summit on Evolution are:
- Origin of life.
- Evolution of plants and animals.
- Human Evolution.
- Evolution and infectious diseases.
- Evolution vs. creationism/ID: An entire session of the summit focuses directly on containing the spread of creationism and intelligent design while improving the public’s understanding of evolution throughout America and elsewhere.
Dates: 22 to 26 August 2009
Place: Campus GAIAS-USFQ and Conventions Centre of the Puerto Baquerizo Moreno Municipality, San Cristobal Island, province of Galápagos, Ecuador
Further information: http://wse2.usfq.edu.ec
Notes:
Universidad San Francisco de Quito
Universidad San Francisco de Quito (USFQ) is an Ecuadorian private non-profit liberal-arts university. Founded in 1988 by the Corporación de Promoción Universitaria (CPU)--its umbrella non-profit foundation, USFQ was the first totally private self-financed university in Ecuador. USFQ has a strong academic reputation, and in 2009 it was ranked 1st in Ecuador in relation to the number of peer-reviewed scientific publication. USFQ employs about half of the PhDs in Ecuador. USFQ is officially recognised by the Ministry of Education of Ecuador and accredited by CONESUP.
World Summit on Evolution
The World Summit on Evolution is an evolutionary biology meeting hosted at the Galapagos Islands by Universidad San Francisco de Quito USFQ. Its focus is on recent research and new advances in our understanding of evolution and the diversity of life. The First World Summit on Evolution took place between 09 and 12 June 2005 at the Galapagos Islands, it was widely-publicised by the most important national and international media.
Location
The World Summit on Evolution takes place at GAIAS, The Galapagos Academic Institute for the Arts and Sciences), an institute part of the Universidad San Francisco de Quito. GAIAS was established in 2002 at the capital town of the Galapagos province, Puerto Baquerizo Moreno, on the island of San Cristobal, one of the largest of the Galapagos Island. The 4.5 hectares GAIAS campus is the only university campus on the Galapagos islands. GAIAS was founded on the principle that beyond being a college and center for the promotion and advancement of evolutionary science in Ecuador, it will become a first-rate institution for international students and researchers.
The Dog and the Butcher
Vía: Sicrono y PuntoGeek
The Dog and the Butcher by Jonathan Holt from Jonathan Holt on Vimeo.
15 agosto 2009
Cambio Climático - Global Warming
Exotic prehistoric fauna in Germany
When Messel Pit was located at the present latitude of Sicily, it was home to a very special fauna, including the primeval horse and the ancestors of today’s birds. 47 million years ago Messel was covered by dense primeval forests with warm, wet climate. Surveys by the Senckenberg Research Institute carries out in the Messel Pit, a UNESCO World Natural Heritage Site, have discovered about 3,000 fossil remains, including some beautiful and interesting animals:
A reptile about 80 centimetres long, the bulldog of the lizard world, closely related to the Gila monsters (Helodermatidae), a family found today just in southwestern USA and Central America. These lizards are renowned by being venomous.
Jewel beetles of the family Buprestidae, whose living representatives can now only be found in the Tropics. “The exquisite coloration is created by refraction at different layers of the chitin carapace,” explains Dr. Sonja Wedmann.
A rodent of the genus Masillamys recovered nearly whole, allowing identification of the fossilised remains of its stomach contents. The extremely well-preserved outlines of the body reveals this ancient rodent had a thick, short-haired coat of fur. The short legs typical of the genus suggest it once lived on the floor of the primeval forest surrounding Messel.
Full size image of Lizard here
Full size image of Beetle here
Among the mammals found, the famous Leptictidium auderiense, star among the Messel fossils thanks to the BBC documentary "Walking with Beasts". Leptictidium had a highly specialised locomotor system. Its extraordinarily long tail with 40 vertebrae, long back legs and reduced front ones point to a bipedal gait.
Fossil of Leptictidium (Wikipedia)
Leptictidium as reconstructed in BBC documentary "Walking with Beasts".
Among the total of 6,773 finds recovered at Messel Pit in 2007 and 2008, there were 1,929 fossilised remains of vertebrates, 1,403 insects and 3,441 plant remains. The information contained in the finds provide the scientists of the Senckenberg Research Institute data on the occurrence of individual species, their bodily structures and lifestyles, and the evolutionary history of animal groups. In addition, the research results help to reconstruct the Eocene environment and give clues to the relationship between climate and biodiversity.
Based on information provided by the Senckenberg Research Institute and Natural History Museum, to whom credit for all images goes to.
Full news at Discovery Channel: http://blogs.discovery.com/news_animal/2009/08/prehistoric-gila-monster-furrycoated-rodent-and-more-unearthed.html
14 agosto 2009
Rapid evolution may be reshaping forest birds’ wings
In areas of Canada where loggers have chewed away the conifer forest that once blanketed most of the country, the long wing feathers, or primary feathers, of 21 mature-woodland species of birds has overall gained about 2.23 millimeters on average during the past century. That uptick roughly matches the magnitude of differences between sexes. In contrast, species from areas in New England (deforested during previous years but rebounded into green woodland again) have a trend back toward rounder wing tips. Eight mature-woodland species had lost, on average, some 2.37 millimeters on those long primary feathers.
"Birds aren’t passive victims of environmental change. As bird species face new challenges, they respond to the extent they can. Birds are not like sitting ducks," said André Desrochers of the Center for Forest Research at Laval University in Québec City during a report he presented on August 13 in Philadelphia at a meeting of the American Ornithologists’ Union..
Desrochers argues that rapid evolution is the most straightforward explanation for his findings.
By ScienceNews, contributed by Susan Milius
Read full story at: http://www.sciencenews.org/view/generic/id/46471/title/Rapid_evolution_may_be_reshaping_forest_birds%E2%80%99_wings
Tropical bird theft at UK Natural History Museum
The bird ‘skins’ were stolen on Wednesday 24 June 2009. The specimens stolen comprise a number of brightly-coloured tropical birds, like cotingas and paradise-birds, some of which are uncommon in collections and, therefore, of especial scientific concern. The Museum is working with the police and the Wildlife Crime Unit on the matter.
Anyone with any information on this crime should ring DI Wylie via the non-emergency number +448453300222, citing crime reference number D3/09/450. Alternatively, call Crimestoppers (an independent charity) anonymously on +44800555111.
Read the full news at the Natural History Museum website: http://www.nhm.ac.uk/about-us/news/2009/august/tropical-bird-theft-at-natural-history-museum.html
Read the full Museum targeted in tropical bird theft press release: http://www.nhm.ac.uk/about-us/press-office/press-releases/2009/natural-history-museum-targeted-in-tropical-bird-theft.html
Polar researchers fouling nature
Research stations in Antarctica are sullying the pristine environment by improperly disposing of sewage waste, reports a study published this month in Polar Research. Twenty-eight countries have a total of total of 82 research stations in the Earth's southern-most landmass, and "they need to take action to prevent the release of microorganisms to the Antarctic environment," said Fredrik Gröndahl of the Royal Institute of Technology in Stockholm, who led the study.
"It's phenomenally expensive to do anything down there," says Gröndahl. "But if we want to preserve Antarctica as pristine as possible, we need to take [on] the costs."
Posted at The Scientist by Alla Katsnelson at 14th August 2009 03:51 PM GMT
Read the complete story at: http://www.the-scientist.com/blog/display/55889/
13 agosto 2009
Ecological Harm in Hawaii: Invasive Wasps with New Life Histories disrupt native Hawaiian wildlife
"They're consuming anything from geckos to shearwater to tree lice to more juicy items that you would expect them to eat, like caterpillars. They're just like little vacuum cleaners," said Erin Wilson, who recently completed her doctorate at UC San Diego and is the lead author of the study reported in the Proceedings of the National Academy of Sciences this week.
The sheer numbers are changing the ecology of Hawaii's endangered ohia woodlands and subalpine shrublands. "It's not just what they're killing," Wilson said. "They're also collecting great amounts of nectar, drawing down the resources for anything else that might want to feed on it whether it's native insects or birds like the Hawaiian honeycreepers."
Read full news at: http://www.sciencedaily.com/releases/2009/07/090720190609.htm
27 julio 2009
Noblella coloma sp. nov.
Abstract.-- We describe a new species of Noblella from the western slope of the Ecuadorian Andes. The new taxon is distinguished from all other species in the genus by lacking dorsal marks (i.e., interobital bar, scapular and sacral chevrons) and by having a bright orange venter. The new species and Noblella heyeri are the only species of Noblella reported in the Pacific Andean versant. We provide an osteological description of the new species and a key for the species in Noblella.
Cita / Citation: Guayasamín, J.M., A. Terán-Valdez. (2009) A new species of Noblella (Amphibia: Strabomantidae) from the western slopes of the Andes of Ecuador. Zootaxa 2161: 47–59.
Mas información: www.mapress.com/zootaxa/2009/f/z02161p059f.pdf
New Taxonomy Centrolenidae
Abstract.-- Based on a molecular phylogeny, a new phylogenetic taxonomy that is compatible with both the International Code of Zoological Nomenclature (ICZN) and the PhyloCode is proposed for Glassfrogs and their sister taxon, Allophryne ruthveni. The arrangement presented herein emphasizes the recognition of clades having (i) significant statistical support and congruence among phylogenetic estimation methods (i.e., parsimony, maximum likelihood, and Bayesian inference criteria), (ii) congruence among genetic markers, and (iii) morphological and/or behavioral distinctiveness. Also, when previously recognized groups are recovered as monophyletic or nearly monophyletic, we propose taxa that minimize the number of name changes required to make these groups monophyletic, preserving the names and contents of previous classifications (i.e., nomenclatural stability). The evolutionary proximity of Centrolenidae and Allophrynidae is recognized by combining these families into an unraked taxon, Allocentroleniae—a proposal that maintains the traditional names and species contents of Centrolenidae and Allophrynidae. We arrange centrolenid diversity in two subfamilies: Centroleninae and Hyalinobatrachinae. Within Centroleninae, the diagnosis and species content of the genera Centrolene, Cochranella, and Nymphargus are modified; Teratohyla is resurrected and modified, and Chimerella, Espadarana, Rulyrana, Sachatamia, and Vitreorana are proposed as new genera. The other subfamily, Hyalinobatrachinae, contains the new genus Celsiella and a modified Hyalinobatrachium that fully corresponds to the former fleischmanni Group. Additionally, the genus Ikakogi is described. Ikakogi could not be assigned with confidence to either subfamily and it is placed as incertae sedis in Centrolenidae. The data at hand suggest that Ikakogi tayrona is a lineage as old as the subfamilies Hyalinobatrachinae and Centroleninae. The revised taxonomy differs markedly from previous arrangements, which were based on phenetics and few morphological characters. Most of the genera defined herein are confined to distinct biogeographic regions, highlighting the importance of geography in the speciation of Glassfrogs. The principal limitation of this proposal is that it is based on an incomplete sampling of taxa (54% of the recognized Glassfrogs). Although diagnoses are based on phenotypic traits, there are several cases (16% of all species) in which the allocation of species is ambiguous because of morphological homoplasy and the lack of molecular data. Finally, in an attempt to facilitate species identification, comparison, and generic placement, we provide photographs for most (~ 96%) of the recognized centrolenid species.
Cita / Citation: Guayasamin, J. M., S. Castroviejo-Fisher, L. Trueb, J. Ayarzagüena, M. Rada, y C. Vilà. (2009) Phylogenetic systematics of glassfrogs (Amphibia: Centrolenidae) and their sister taxon Allophryne ruthveni. Zootaxa 2100:1-97.
Mas información: http://www.mapress.com/zootaxa/2009/f/zt02100p097.pdf
Abstract.-- Glassfrogs (family Centrolenidae) represent an exceptionally diverse group among Neotropical anurans, but their evolutionary relationships never have been assessed from a molecular perspective. Mitochondrial and nuclear markers were used to develop a novel hypothesis of centrolenid phylogeny. Ingroup sampling included 100 terminals, with 78 (53%) of the named species in the family, representing most of the phenotypic diversity described for the group. Thirty-five species representing taxa traditionally associated with glassfrogs were used as outgroups. Gene sampling consisted of complete or partial sequences of three mitochondrial (12S, 16S, ND1) and three nuclear markers (c-myc exon 2, RAG1, POMC) for a total of approximately 4362bp. Phylogenies were estimated using maximum parsimony, maximum likelihood, and Bayesian analyses for individual genes and combined datasets. The separate analysis of mitochondrial and nuclear datasets allowed us to clarify the relationships within glassfrogs; also, we corroborate the sister-group relationship between Allophryne ruthveni and glassfrogs. The new phylogeny differs significantly from all previous morphology-based hypotheses of relationships, and shows that hypotheses based on few traits are likely to misrepresent evolutionary history. Traits previously hypothesized as unambiguous synapomorphies are shown to be homoplastic, and all genera in the current taxonomy (Centrolene, Cochranella, Hyalinobatrachium, Nymphargus) are found to be poly- or paraphyletic. The new topology implies a South American origin of glassfrogs and reveals allopatric speciation as the most important speciation mechanism. The phylogeny profoundly affects the traditional interpretations of glassfrog taxonomy, character evolution, and biogeography-topics that now require more extensive evaluation in future studies..
Cita / Citation: Guayasamin, J. M., S. Castroviejo-Fisher, J. Ayarzagüena, L. Trueb y C. Vilà. (2008) Phylogenetic relationships of glassfrogs (Centrolenidae) based on mitochondrial and nuclear genes. Molecular Phylogenetics and Evolution 48:574-595.
Mas información: http://www.puce.edu.ec/zoologia/vertebrados/personal/colaboradores/jmguayasamin/index.html
Pristimantis andinognomus sp. nov.
Abstract.-- We describe a new species of Pristimantis from a cloud forest at 2450–2800 m in the Cordillera Oriental in southern Ecuador (Zamora Chinchipe). The new species has a maximum snout–vent length of 17.9 mm (average SVL of 21 males = 12.3 mm ± 1.2, and of 19 females = 15.9 mm ± 1.3). This new species is the second smallest frog from Ecuador and smallest Pristimantis. Morphologically and phylogenetically, the new species is similar to P. caeruleonotus and P. colodactylus. It is distinguished from them and its congeners by its size, tuberculation, a distinct color pattern consisting of tan blotches on dorsum, spots on a brown venter, minute brown spots on anterior and posterior surfaces of the thighs, and other morphological features. Determination of small body size in frogs is discussed and meristic data of 40 minute frogs are compiled..
Cita / Citation: Lehr, E. & L. A. Coloma. (2008) A minute new Ecuadorian Andean frog (Anura: Strabomantidae, Pristimantis). Herpetologica 64(3): 354–367..
Mas información: http://www.puce.edu.ec/zoologia/vertebrados/personal/lacoloma/index.html
Cochranella mcdiarmidi sp. nov.
Abstract.-- We describe a new species of glassfrog assigned to the genus Cochranella (Amphibia: Anura: Athesphatanura: Centrolenidae) from the Foothill Evergreen forests on the southeastern Andean slopes of Ecuador and northeastern Andean slopes of Peru. The new species is characterized by its moderate-sized body (25.4–26.9 mm in adult males), medium-sized eyes (eye diameter/third disc width = 1.4–1.9), distinctive coloration in life (olive green with light spots) and in preservative (grayish lavender with pale spots), dorsal skin covered with flat warts and low tubercles, parietal peritoneum mostly white (covered by iridophores), thick ulnar folds, and extensive hand and foot webbing. In addition, we provide the first record of Nymphargus posadae from Peru, found in sympatry with the new species at the Cordillera del Cóndor..
Cita / Citation: Cisneros-Heredia, D.F., P. J. Venegas, M. Rada & R. Schulte. 2008. A new species of Glassfrog (Anura, Centrolenidae) from the Foothill Andean forests of Ecuador and Peru. Herpetologica 64(3): 342-353..
Mas información: http://www.cisneros-heredia.org/public
Amazonian Amphibian Diversity
Abstract.-- The Neotropics contains half of remaining rainforests and Earth's largest reservoir of amphibian biodiversity. However, determinants of Neotropical biodiversity (i.e., vicariance, dispersals, extinctions, and radiations) earlier than the Quaternary are largely unstudied. Using a novel method of ancestral area reconstruction and relaxed Bayesian clock analyses, we reconstructed the biogeography of the poison frog clade (Dendrobatidae). We rejected an Amazonian center-of-origin in favor of a complex connectivity model expanding over the Neotropics. We inferred 14 dispersals into and 18 out of Amazonia to adjacent regions; the Andes were the major source of dispersals into Amazonia. We found three episodes of lineage dispersal with two interleaved periods of vicariant events between South and Central America. During the late Miocene, Amazonian, and Central American-Chocoan lineages significantly increased their diversity compared to the Andean and Guianan-Venezuelan-Brazilian Shield counterparts. Significant percentage of dendrobatid diversity in Amazonia and Chocó resulted from repeated immigrations, with radiations at <10.0 million years ago (MYA), rather than in situ diversification. In contrast, the Andes, Venezuelan Highlands, and Guiana Shield have undergone extended in situ diversification at near constant rate since the Oligocene. The effects of Miocene paleogeographic events on Neotropical diversification dynamics provided the framework under which Quaternary patterns of endemism evolved.
Taxonomic proposals: Some changes to Grant et al.’s taxonomy were suggested by this paper, including:
- The proposed split of Dendrobatidae into two families (i.e., Allobatidae and Dendrobatidae) was not followed and this paper returned Dendrobatidae to a single family.
- This paper restricted Colostethus to the group of C. latinasus and allies (species in Colostethus 1 clade). Colostethus sensu lato is applied to the aggregate of species found in Colostethus 1 and 2 clades in their phylogeny.
- This paper synonymized Adelphobates, Excidobates, Minyobates, Oophaga, and Ranitomeya in the genus Dendrobates.
- Allobates craspedoceps was found within Hyloxalus, so a new combination was proposed: Hyloxalus craspedoceps.
- Hyloxalus argyrogaster was found with Colostethus sensu lato, so its new combination is Colostethus argyrogaster.
- Allobates peruensis (closely allied to A. kingsburyi) is a valid name.
Cita / Citation: Santos, J.C., et al. (2009) Amazonian Amphibian Diversity Is Primarily Derived from Late Miocene Andean Lineages. PLoS Biol 7(3): e1000056. doi:10.1371/journal.pbio.1000056.
Mas información: http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1000056
Enyalioides touzeti sp. nov.
Abstract.-- We describe a new species of Enyalioides from lowland cloud forests in southwestern Ecuador. This represents the third species in the genus known to occur west of the Andes in South America; the other two species are E. heterolepis and E. oshaughnessyi. Among other characters, the new species can be distinguished from other members in the genus by having small, keeled, paravertebrals; a series of skin folds on the lateral aspects of body and neck; size-homogeneous scales on body and limbs; distinct caudal segments; and an extensive dark patch on the gular region of adult males. Morphological similarity suggests that the new species, which we call E. touzeti, is closely related to E. oshaughnessyi.
Cita / Citation: Torres-Carvajal, O. et al. (2008) A new species of Enyalioides (Iguanidae: Hoplocercinae) from southwestern Ecuador. Pap. Avulsos Zool. (São Paulo) 48(20): 227-235 . Available from: <http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0031-10492008002000001&lng=en&nrm=iso>.
Mas información: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0031-10492008002000001&lng=en&nrm=iso