BIODIVERSIDAD
Severe Loss of Suitable Climatic Conditions for Marsupial Species in Brazil: Challenges and Opportunities for Conservation[107]
New-Species "Heaven" Discovered in Peru[108]
Se necesitan grandes áreas protegidas para salvar a las especies[109]
La sexta extinción[110]
Questions and answers about biodiversity[111]
Berkeley Earth tracks climate change - video
[112]
La ONU alerta sobre cambios sin precedentes en la tierra[113]
Panel Internacional de Biodiversidad y Servicios Ecosistémicos [114]
Large-scale marine ecosystem change and the conservation of marine mammals[115]
Facebook de la biodiversidad[116]
Taxonomy: the naming crisis[117]
Plataforma Intergubernamental sobre Biodiversidad y Servicios del Ecosistema (IPBES)[118]
2011, el Año de los bosques[119]
Pérdida de biodiversidad y aumento de enfermedades[120]
Biodiversidad y Bienestar Humano en América Latina y el Caribe [121]
Los Andes explican la riqueza de vida en la Amazonia[122]
Biodiversity: facts and figures[123]
Wanted: an IPCC for biodiversity[124]
Hundreds of New Species Found in Papua New Guinea[125]
Deforestation Rate Continues to Plunge in Brazil[126]
Soja, ciencia, justicia y política[127]
Especies africanas de agua dulce amenazadas: medios de subsistencia en peligro[128]
Inventarios Globales de Biodiversidad: Una Respuesta a la Crisis Taxonómica por Lawrence M. Page[129]
Amenaza a la Biodiversidad y Que Se Puede Hacer,por Daniel Simberloff[130]
Simbiosis,mutualismo y la diversidad de frutos silvestres[131]
Mejillones invasores en la Cuenca del Plata, Argentina[132]
Especiación y Biodiversidad por Edward O. Wilson[133]
Recuento de peces y organismos marinos[134]
Abejas en cafetales de sombra mejoran biodiversidad[135]
La Búsqueda de Medicinas por Mark J. Plotkin [136]
La Caatinga perdio el 45 % de su masa vegetal[137]
Inventario de biodiversidad marina: ultimo informe[138]
Las aguas de Australia, Japón y China son las más ricas en especies marinas[139]
El Mediterraneo, uno de los mares mas amenazados[140]
AMPHIBIANS WIPED OUT BEFORE THEY ARE DISCOVERED[141]
Incendio en el Pantanal[142]
12 tendencias ambientales en America del Sur[143]
Una cuna de biodiversidad en las Tablas de Daimiel[144]
ATLAS OF BIODIVERSITY RISK[145]
ESPECIALES: corredores, conectividad, cambio climatico y participacion social en conservacion[146]
How many species are there?[147]
Politics is a key factor in biodiversity[148]
El Gran Chaco y la Deforestacion[149]; Entrevista a Jorge Morello[150]
IPBES,Plataforma Intergubernamental sobre Biodiversidad y Servicios de Ecosistemas[151]
Vida y milagros de la biodiversidad[152]
UE y la biodiversidad[153]
El 40% de la economía mundial depende de la naturaleza[154]
Triatlón por la vida del Daríen[155]
Miles de personas se conectan con la naturaleza a través de la campaña de la UE[156]
La minería en Colombia: El gran dilema[157]
Donde mueren las especies[158]
Lagartos sucumben al calentamiento global[159]
La pérdida de especies y el Hombre[160]
El 4% de la deforestación mundial ocurre en Mexico[161]
Climate Change Causing Lizards to 'Wink Out of Existence[162]
Nations Ignoring Biodiversity Treaty, U.N. Says[163]
La ONU y la pérdida de biodiversidad[164]
It's a microbial world[165]
Biodiversidad, definiciones y conceptos[166]
Barómetro para la biodiversidad[167]
La perdida de biodiversidad según E.O. Wilson[168]
Faltan estudios para la eficaz protección de la biodiversidad[169]
Efecto bumerán en Monsanto, en los Estados Unidos[170]
La pérdida de biodiversidad es el mayor desafío[171]
Los Wichi[172]
Biocombustibles y seguridad alimentaria-1-.doc
La destrucción del Chaco
Un tercio de los europeos desconoce la biodiversidad
ENTREVISTAS
Claudio Campagna[173];
David Gorla y el Mal de Chagas[174]
Cursos avanzados
[[175]]
Obituario
Lynn Margulis[176]
Juan Carlos Chebez[177][178]
Paul S. Martin (1928–2010): Luminary, Natural Historian, and Innovator[179]
Journal of Biogeography Editor´s choice[180]
Frontiers of Biogeography[181]
Biogeografia Bulletin of the Systematic & Evolutionary Biogeographical Association[182]
...NOTICIAS
These Mammals Pack a Toxic Punch[183]
Mice sing to impress the girls [184]
North American Bat Death Toll Exceeds 5.5 Million From White-nose Syndrome[185]
Cronopio: un mamífero que vivía entre dinosaurios[186]
Estado de la población del Mundo 2011[187]
Nuevo estudio independiente confirma el calentamiento global[188]
A large population of king crabs in Palmer Deep on the west Antarctic Peninsula shelf and potential invasive impacts[189]
Cretaceous-Paleogene mammal extinctions and diversification[190]
The Influence of Late Quaternary Climate-Change Velocity on Species Endemism[191]
Quien es el pariente y como llegó el zorro a Malvinas?[192]
Vampire bats can sense the heat of blood flowing in the veins of their prey [193]
A Cheap Imitation Is Sometimes Best[194]
El oso mas grande del mundo[195]
Bat Hibernation Keeps Rabies Going[196]
Did Llama Dung Spur the Rise of Andean Civilization?[197]
Mammal Rediscovered after 113 Years[198]
Tuberculosis followed the fur trade[199]
Leprosy and armadillos[200]
Early warning signs for ecosystem collapse?[201]
Language May Have Helped Early Humans Spread Out of Africa[202]
Mountain ranges as safe places for species facing climate change[203]
Study Finds Energy Limits Global Economic Growth[204]
Premio Crafoord a Ilkka Hanski[205]
Bumblebee Decline Confirmed Across U.S.[206]
Conejos Pigmeos en Peligro en los Estados Unidos[207]
Nómades tibetanos, desertificacion y cambio climático[208]
Mammoth-Killer Impact Rejected[209]
Consecuencias de la minería de montaña[210]
Drought-Induced Reduction in Global Terrestrial Net Primary Production from 2000 Through 2009[211]
Ancient Crocodile Chewed Like a Mammal[212]
Burrowing Moles Breathe Easy[213]
Tiny Amphibian, Long Life[214]
Marmots Thrive on Climate Change[215]
The Science Show and the Creation - the story of Charles Darwin writing his major work[216]
Report maps perils of warming
… For example, the report shows that each 1 °C of warming will reduce rain in the southwest of North America, the Mediterranean and southern Africa by 5–10%; cut yields of some crops, including maize (corn) and wheat, by 5–15%; and increase the area burned by wildfires in the western United States by 200–400%[217]
Millennium assessment of human behavior[218]
The white-nose syndrome[219]
Los neandertales viven en nuestros genes[220]
DNA Sequence of Neandertal genome[221]
Somos más neandertales de lo que pensábamos[222]
La mitad de los primates en riesgo de extinción [223]
El estudio del monito del monte aporta luz sobre la evolución de los mamíferos[224]
REVISTAS DE MAMIFEROS/MAMMAL JOURNALS
MASTOZOOLOGIA NEOTROPICAL</p>
[225]
Ultimo numero vol 17[226]
MAMMALIAN BIOLOGY- Zeitschrift für Säugetierkunde</p>[227]
JOURNAL OF MAMMALOGY</p>[228]
GALEMYS</p>[229]
MAMMAL REVIEW</p>[230]
AUSTRALIAN MAMMALOGY</p>[231]
MAMMALIA</p> [232]
ACTA THERIOLOGICA</p> [233]
JOURNAL OF MAMMALIAN EVOLUTION[234]
ACTA THERIOLOGICA SINICA[Acta Theriologica Sinica]
MARINE MAMMAL SCIENCE[235]
AQUATIC MAMMALS[236]
MAMMAL STUDY (JAPAN)
ZOOTAXA[237]
REVISTA MEXICNA DE MASTOZOOLOGIA [238]
Control de roedores en municipios[239]
La SAREM y Su Historia[240]
PROTOCOLO DE LA ASM PARA EL MANEJO DE MAMIFEROS EN INVESTIGACION/Guidelines of the American Society of Mammalogists for the use of wild mammals in research[241]
PROGRAMA de Conservación de Murciélagos de Argentina[242]
XENARTHRA[243]
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LIBROS/Books
BONES,CLONES AND BIOMES:THE HISTORY AND GEOGRAPHY OF RECENT NEOTROPICAL MAMMALS
BRUCE D. PATTERSON AND LEONORA P. COSTA Eds
[244]
Review: Are We Really Getting Conservation So Badly Wrong? [245]
Mamíferos de Argentina Sistemática y Distribución (SAREM, 2006)
Editores: Rubén M. Barquez, M. Mónica Díaz, Ricardo A. Ojeda
Interesados contactar a Analia Autino: pidba@arnet.com.ar
FACEBOOK/Mammal Groups
International Federation of Mammalogists [246]
Neotropical Mammalogy[247]
Mamíferos de Venezuela/Mammals of Venezuela [248]
Mastozoólogos Colombianos/ Mammalogists from Colombia[ http://www.facebook.com/groups/19421246899/]
Sociedad Argentina para el Estudio de los Mamíferos (SAREM)/Mammal Society of Argentina[249]
Sociedad Brasileira de Mastozoologia [250]
Sociedad Colombiana de Mastozoologia/Mammal Society of Colombia[251]
Australian Mammal Society [252]
The Mammal Society [253]
American Society of Mammalogists [254]
Sociedad Peruana de Mastozoología [255]
GRUPOS PARTICULARES
World Lagomorph Society [256]
Homenajes a CHARLES R. DARWIN
|
En el bicentenario de su nacimiento (12 Febrero de 1809) y centésimo quincuagésimo aniversario de “El Origen de las Especies” (24 noviembre 1859)
Bicentennial Darwin Day Events
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Noticias DEL GiB
2012
Durante el mes de setiembre los Dres Jane Bowles, Paul Handford (University of Western Ontario, London, Canada) y Ricardo Ojeda (GiB) estuvieron recorriendo el NOA con el propósito de elaborar una guía biogeográfica y de identificación de elementos distintivos de las grandes ecorregiones del Monte, Puna, Selva de Yungas y Chaco.
Es un gusto anunciarles que Verónica Chillo ha sido galardonada con la Beca Fullbright para desarrollar un período de formación profesional en el laboratorio del Dr. James F. Reynolds de la Universidad de Duke (North Carolina, Norteamérica) entre los meses de Octubre 2012 a Febrero 2013. Durante su estadía profundizará sobre el análisis de umbrales de degradación por pastoreo y la potencial ocurrencia de estados degradados del desierto del Monte. Felicitaciones!
Durante el mes de Julio, Paola Sassi participó en el Primer Congreso Conjunto de Biología Evolutiva, que reunió a diversas sociedades: American Society of Naturalists (ASN), Canadian Society for Ecology and Evolution (CSEE), European Society for Evolutionary Biology (ESEB), Society for the Study of Evolution (SSE), y Society of Systematic Biologists (SSB)". Este congreso se llevó a cabo entre el 6 y el 10 de Julio de 20012 en Ottawa, Canada, y se presentaron resultados del proyecto "Ecología fisiológica y evolutiva de roedores de ambientes áridos, respuestas a compromisos ambientales y su variabilidad", con el trabajo: ALTITUDINAL EFFECTS ON ENERGY ACQUISITION ABILITY IN A SMALL MAMMAL (Phyllotis xanthopygus, Rodentia: Muridae).
Asimismo, en el mes de Julio, Agustina Ojeda participó en calidad de asistente local en instrucción y organización del Cuarto taller de entrenamiento en el proyecto de códigos de Barras Genéticos “Fourth Leadings Labs Training Workshop” (Canadian Centre for DNA Barcoding- International Barcode of Life), realizado en el Museo Argentino de Ciencias Naturales “ Bernardino Rivadavia”. El mismo contó con alrededor de 70 participantes entre estudiantes de grado, postgrado e investigadores y profesionales de distintos centros de investigación de nuestro país y de otros países latinoamericanos como, Bolivia, Brasil, y Colombia.
En el marco del Programa de Cooperación Científico-Tecnológico entre el Ministerio de Ciencia, Tecnología e Innovación Productiva de la República Argentina (MINCYT) y el Ministry of Higher Education, Science and Technology de la República de Eslovenia (MHEST) fue aprobado el proyecto sobre la ecología trófica del Lirón grís (Glis glis) en diferentes hábitats. En el mes de Junio Mariana Dacar viaja a Koper, Eslovenia, para
dar inicio al mismo y organizar el protocolo de preparado y análisis microhistológico en el laboratorio del Dr Boris Krystufek, Science and Research Centre, University of Primorska, Koper, Slovenia.
Los proyectos PIP-CONICET de las Dras Paola Sassi y Claudia Campos resultaron seleccionados para el desarrollo de sus investigaciones. Felicitaciones!.
Con gran placer anunciamos que Fernanda Cuevas defendió y obtuvo su Doctorado el pasado 27 de Marzo con su investigación "Ecología del jabalí, Sus scrofa, en el desierto del Monte central, Argentina" (Universidad Nacional de Río Cuarto, Córdoba). Felicitaciones Doctora!!! y adelante con mas estudios...
2011
Con enorme placer recibimos la noticia del ingreso de Agustina Ojeda a la carrera del investigador del CONICET. Adelante
Agustina...los ratones te esperan!.
El Dr Michael Wisdom (US Forest Service Pacific Northwest Research Station)se encuentra desarrollando una estadía en nuestro laboratorio como parte de
su proyecto de investigación y docencia con Beca Fullbright (Experimental Design and Resource Selection Methods for Landscape Assessment of
Vertebrate Responses to Human Disturbances and Environmental Changes in Argentina).
A Australia!!..Entre Setiembre a Diciembre Soledad Albanese estará desarrollando una estadía Posdoctoral en el Laboratorio de Chris Dickman en el Depto de Biología
de la Universidad de Sydney http://sydney.edu.au/science/biology/about_us/academic_staff/dickman_chris/.
El período esta financiado por el programa de estancias en el exterior del CONICET.
Ricardo Ojeda ha sido designado Editor Asociado del Journal of Mammalogy,revista de la Sociedad Norteamericana de Mastozoólogos.
El 8 de Julio Daniela Rodriguez presentó y defendió su Tesis doctoral sobre diversidad de ensambles de pequeños
y medianos mamíferos del desierto templado del Monte (Universidad Nacional del Comahue)...Felicitaciones Doctora!
El día 28 de Junio Agustina Novillo presentó y defendió su Tesis doctoral sobre gradientes altitudinales y latitudinales de diversidad en pequeños mamíferos de los Andes áridos (Fac de Cs Naturales, Univ Nac de Tucumán)... Felicitaciones Doctora!
Paola Sassi ha regresado recientemente de una estadía de corta duración en el Departamento de Genética, CESAR –HOFFMANN LAB (BIO 21 INSTITUTE) de la Universidad de Melbourne bajo la Dirección de Ary A. Hoffmann. La misma fue subsidiada por el CONICET, Argentina, como parte del programa de estadias en el exterior.
Cambios en el staff del GiB: a partir de Enero Cecilia Lanzone desarrolla su actividad investigativa en el Dpto. de Genética de la Facultad de Ciencias Exactas, Químicas y Naturales de la Universidad Nacional de Misiones. Los mejores deseos en
sus investigaciones y en su nuevo lugar!.
Ricardo Ojeda ha sido designado Co -Chair del Comité de Relaciones Internacionales, y miembro del Comité de Conservación de la American Society of Mammalogists[257].
Agustina Novillo y Daniela Rodriguez resultaron merecedoras de la Beca Posdoctoral CONICET para desarrollar sus investigaciones sobre patrones de diversidad de roedores sigmodontinos en los Andes centrales, y la influencia del pastoreo caprino sobre la diversidad de mamíferos, respectivamente.
CAMPAÑAS
Ultima campaña 2011!!...Alrededores de El Nevado, Mendoza; Paola Sassi y Agustina Ojeda
POSTERS
Invasiones biológicas.La introducción y expansión de organismos en regiones fuera de su rango de distribución natural, junto a la degradación y fragmentación de hábitats, cambio climático y tráfico de vida silvestre, son las causas mas importantes de pérdida de la biodiversidad. En Argentina se encuentran aproximadamente 17 especies de mamíferos exóticos invasores distribuidos desde los Andes a la costa Atlántica. El poster de Invasiones sintetiza las características de las distintas especies, su distribución, fecha de entrada, y dieta, entre otros.
Biodiversidad del ecosistema Andino.El ecosistema montañoso de los Andes ha jugado un papel importante en la evolución y diversificación de la biota Sudamericana. Sin embargo, es muy poco lo que aún conocemos sobre la riqueza y abundancia de sus especies animales y vegetales. El Grupo de Investigaciones de la Biodiversidad (GiB-IADIZA)preparó este póster que acerca al público en general la riqueza de los mamíferos de las tierras Andinas. Material para difusión institucional, educación, actividades docentes y divulgación al público.
Los interesados pueden solicitarlos en el GiB
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CONGRESOS 2012
III Congreso de de la Sociedad Peruana de Mastozoología,7 al 11 de Octubre,Piura, Peru
25 Reunión Argentina de Ecología[258]
II Congreso Latinoamericano y las XXV Jornadas Argentinas de Mastozoología, 6-9- Noviembre, Buenos Aires, Argentina [259]
==
Mammal functional diversity loss under human-induced disturbances in aridlands ==
Human activities are drastically changing the composition of mammal communities and increasing
species local extinctions. Although it is well recognized that species influence the way in which
ecosystems function through the diversity of resource use traits, little is known regarding the consequences
of ecosystem functioning on changing biodiversity. We summarized studies that analyzed the
effects of anthropogenic disturbances on mammal assemblages in arid and semi-arid lands of the world.
We analyze for the first time changes in functional diversity values under a wide variety of disturbances
using a meta-analysis.
General mean effect size was significantly negative and marginally heterogeneous. Grouping into
ecosystems showed a varied response, mostly negative but not significant. When considering disturbance
types as moderator factor, functional diversity responds in a negative way to all types, but the
strongest effects were seen when we analyzed the mechanism by which disturbance affects ecosystem.
‘Herbivory’ effect was the least aggressive, and contrary, ‘species change’ strongly and negatively affected
functional diversity. When disturbance generates changes in species and resources, and new state
properties highly differ from the initial state property, the regime shift seen in vegetation has drastic
consequences over mammal functional diversity. This loss of functional diversity may generate positive
feedbacks that help to maintain degraded states of the ecosystem (V. Chillo , R.A. Ojeda, 2012, Journal of Arid Environments 87: 95-102)
pdf
Mammal functional diversity loss under human-induced disturbances in aridlands
Human activities are drastically changing the composition of mammal communities and increasing
species local extinctions. Although it is well recognized that species influence the way in which
ecosystems function through the diversity of resource use traits, little is known regarding the consequences
of ecosystem functioning on changing biodiversity. We summarized studies that analyzed the
effects of anthropogenic disturbances on mammal assemblages in arid and semi-arid lands of the world.
We analyze for the first time changes in functional diversity values under a wide variety of disturbances
using a meta-analysis.
General mean effect size was significantly negative and marginally heterogeneous. Grouping into
ecosystems showed a varied response, mostly negative but not significant. When considering disturbance
types as moderator factor, functional diversity responds in a negative way to all types, but the
strongest effects were seen when we analyzed the mechanism by which disturbance affects ecosystem.
‘Herbivory’ effect was the least aggressive, and contrary, ‘species change’ strongly and negatively affected
functional diversity. When disturbance generates changes in species and resources, and new state
properties highly differ from the initial state property, the regime shift seen in vegetation has drastic
consequences over mammal functional diversity. This loss of functional diversity may generate positive
feedbacks that help to maintain degraded states of the ecosystem (V. Chillo , R.A. Ojeda, 2012, Journal of Arid Environments 87: 95-102)
pdf
The population of Ctenomys from the Ñacuñán Biosphere Reserve belongs to Ctenomys mendocinus
Subterranean tuco-tucos of the genus Ctenomys are caviomorph rodents comprising a complex of over 50 nominal species found in the southern half of South America. The validity of several nominal forms awaits a proper assessment. The population of Ctenomys from Ñacuñán Biosphere Reserve (Mendoza, Argentina) has been classically considered to represent a distinct species and has been commonly referred as Ctenomys “eremofilus”. Based on molecular and cytogenetic analysis we assessed the taxonomic status of the Ctenomys population of Ñacuñán. Specimens analyzed showed two very similar chromosome complements (2n=48 and 2n=50), the latter being widely distributed in populations of C. mendocinus. Similarly, haplotypes recovered from Ñacuñán specimens are very similar and sister to those recovered
from specimens of C. mendocinus. Considering this evidence we conclude that the individuals of Ctenomys from Ñacuñán population should be assignable to C. mendocinus.
Key words: Caviomorpha, Karyotype, Monte desert, Ñacuñán Reserve, species limits, taxonomy, Tuco-tucos
(A. Parada, A. Ojeda, S. Tabeni & G. D'Elia, Zootaxa 3402: 61–68)
pdf
Un roedor raro del desierto argentino, Salinomys delicatus (Cricetidae: Sigmodontinae)
El ratón delicado de los salares (Salinomys delicatus) es un pequeño roedor endémico de Argentina. Ha sido
considerado como vulnerable a la extinción dada su distribución restringida y en parches, tamaño poblacional pequeño
y especialización en hábitats salinos. A pesar de que el ratón delicado tiene adaptaciones morfológicas y fi siológicas para
la supervivencia en ambientes áridos y salitrosos, poco es lo que se conoce de su historia natural. El presente trabajo
tiene como objetivo estudiar la historia natural de S. delicatus, reportar nuevas localidades de ocurrencia, caracterizar
el uso de hábitat, su dieta y el ensamble acompañante, y describir su biología reproductiva y morfología. Se registraron
dos nuevos sitios de ocurrencia en ambientes de bosques en galería y bajos salinos en la región noreste de la provincia
de Mendoza (Argentina), siendo las primeras citas para esta provincia. S. delicatus presenta una dieta omnívora, como es
frecuente en otros roedores de desierto, y consume en igual medida semillas, artrópodos y plantas halófi tas. El ensamble
acompañante está compuesto por no más de tres especies de pequeños mamíferos que varían según la localidad, siendo
esta riqueza similar a otros sitios del Monte. La proporción de sexos y el patrón de dimorfi smo sexual mostraron un
marcado desvío hacia las hembras (H:M = 3.6:1.1 y H:M = 1.151 respectivamente). La morfología externa y craneal
presenta una importante variabilidad intra e interpoblacional, sugiriendo que el aislamiento juega un rol importante.
Cuando se consideraron adultos y juveniles, conjuntamente dos de las seis medidas externas (longitud total y longitud de
cabeza y cuerpo) y siete de las 22 medidas craneales resultaron signifi cativamente mayores en hembras que en machos.
Cuando se compararon solo los adultos, cuatro características externas (longitud total, longitud de cabeza y cuerpo,
largo de la cola y peso) y seis medidas craneales fueron signifi cativamente mayores en hembras que en machos. Este
trabajo refuerza la importancia del desarrollo de nuevos estudios más detallados sobre la historia de vida de S. delicatus
y permite reafi rmar la importancia de conservación de esta especie.(D Rodriguez, C Lanzone, V Chillo, P Cuello,S Albanese, A. Ojeda & RA. Ojeda. 2012. Revista Chilena de Historia Natural 85: 13-27, 2012).
pdf
Unvarying diet of a Neotropical desert marsupial inhabiting a variable environment: the case of Thylamys pallidior
Studies on the diet and other aspects of the natural history of Neotropical marsupials have focused
mainly on a few species from tropical and forest habitats.Research on desert marsupials, on the other hand, is almost
absent outside Australia. The desert mouse opossum,Thylamys pallidior, is a small marsupial which inhabits
the arid lands of Argentina, Chile, Bolivia, and Peru. In Argentina, it occurs in the Monte desert, a highly seasonal
system with a heterogeneous landscape which affords a good opportunity to perform comparisons among different
environmental situations. We analyzed fecal samples from 123 individuals and compared their diet among different
seasons, habitat types, sexes, and ages. The diet of T.pallidior was composed of 68.7% of arthropods and 31.3%
of plant material, mainly leaves (24.6%). We found no significant differences in the proportions of any main food
category consumed for any of the factors analyzed.Consumption of both plant and animal material seems to
be important in the diet of T. pallidior which manages to keep their proportions constant despite the strong variability
and seasonality of the habitat. Contrary to most didelphid species, but similarly to most mammals of this area, leaves
seem to represent an important source of food possibly because of their abundance and stability in the Monte
desert. This represents the first study to focus on the diet of a Thylamys species inhabiting an arid environment (Soledad Albanese & María Ana Dacar & Ricardo A. Ojeda; Acta Theriol (2012) 57:185–188)
Mammals of the Monte Desert: from regional to local assemblages
Gran parte del territorio de Sudamerica se compone de una extraordinaria diversidad de regiones áridas y semiáridas,
caracterizadas por un alto número de mamíferos endémicos. En esta revisión caracterizamos la estructura de los ensambles
de pequeños mamíferos de las tierras áridas de Sudamérica,con particular atención en el Desierto del Monte. Proveemos
información sobre características poblacionales, estructura de comunidades, uso de alimentos y hábitats, y respuestas a
perturbaciones. Entre los principales resultados a diferentes escalas se incluyen: la particularidad de los mamíferos y la
tasa de cambio de riqueza entre las tierras áridas de Sudamérica y ecorregiones del Monte; fluctuaciones poblacionales
sincrónicas, pero con gran variabilidad interanual; las estrategias tróficas dominantes son la herbivoría y omnivoría;
la estructura comunitaria se asienta en el uso diferencial de recursos de alimentos y hábitats; finalmente se destaca la importancia
de la matriz de ambientes pastoreados y no pastoreados para el mantenimiento de la biodiversidad.
Ricardo Ojeda,Solana Tabeni,and Valeria Corbalán, Jour Mammalogy, 2011
ASSESSING THE USE OF FUNCTIONAL DIVERSITY AS A MEASURE OF ECOLOGICAL RESILIENCE IN ARID RANGELANDS
It is becoming more apparent that species richness
alone many not be sufficient to fully understand
ecosystem resilience but that functional diversity
(diversity of species having similar effects on an
ecosystem process) may be more relevant. In particular,
response diversity (diversity of species that
respond differently to disturbance) within functional
groups (FG) is suggested to be critical for
resilience. We assess for the first time the use of
response diversity as a measure of resilience in an
empirical study. Our experimental design consisted
of sites with three disturbance intensities during a
grazing exclosure period and the same sites, 1 year
later, after grazing. Plant FGs were identified based
on effect traits related to nutrient cycling and soil
retention, and species richness within groups was
assessed during exclosure and after grazing. To
assess if response diversity could predict loss of
species richness (resilience analysis), response
diversity was calculated only during the exclosure
period, based on traits related to grazing tolerance.
We also assessed the contribution of richness to
response diversity during exclosure (redundancy
analysis). Response diversity was significantly and
highly correlated with species richness within FGs
during disturbance. That is, FGs with the lowest
response diversity were the most affected, disappearing
when disturbance appeared. Richness
within FGs during exclosure was not significantly
correlated with response diversity, showing that
higher richness does not ensure resilience. We
conclude that response diversity can be used to
predict which FGs are more resilient, and hence,
less vulnerable to future disturbance.
Key words: desertification; functional groups;
Insurance Hypothesis; Monte Desert; resilience;
rangeland management; response diversity.
(Verónica Chillo,Madhur Anand,and Ricardo A. Ojeda, 2011 ECOSYSTEMS)
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BIOLOGICAL SOIL CRUST RECOVERY AFTER A LONG-TERM GRAZING EXCLUSION IN THE MONTE DESERT (ARGENTINA)
Disturbance by domestic grazing is recognized as the most widespread stressor of biological soil crust
(BSC) communities. To assess the recovery of the BSC after grazing exclusion, we estimated the
composition, cover, and spatial distribution of biological soil crusts, and their influence on soil nitrogen in
a protected area after 40 years of grazing exclusion (Reserve MaB of Ñacuñán), and in its surrounding
grazed matrix in the central Monte Desert. We considered two spatial scales: at the landscape scale we
estimated vegetation and BSC cover in paired grazed and ungrazed sites of Larrea shrublands; at the
microsite scale we assessed the influence of the dominant vascular plant, Larrea cuneifolia, on crust cover,
and the influence of crust cover on soil nitrogen concentration. Grazing has a negative impact on soil
crusts, which only develop under the protection of vascular plants in grazing areas. Grazing exclusion
favors crust recovery, allowing black, lichen dominated crusts to develop in exposed areas between shrub
canopies. The cover of the moss-dominated crusts was not significantly different at any of the two spatial
scales analyzed. Soil nitrogen was higher in areas under L. cuneifolia and without BSC cover, suggesting
that litterfall inputs currently exceed those from soil crust N2 fixation, perhaps because crust function has
not yet recovered (Diana A. Gómez, Julieta N. Aranibar,Solana Tabeni, Pablo E. Villagra,Irene A. Garibotti, Adrian Atencio; 2011, ACTA OECOLOGICA, 000-000).
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DIFFERENTIAL USE OF VERTICAL SPACE BY SMALL MAMMALS IN THE MONTE DESERT,ARGENTINA
Space use in deserts has usually been considered only along the horizontal dime24 nsion;
however, vertical structure could be an important variable for habitat segregation among
small mammal species. Our study assessed the use of vertical space by small mammals
of the Monte Desert by live-trapping animals at different heights. We recorded 1,336
captures of 4 rodent and 1 marsupial species in 27,600 trap-nights. All 5 species were
captured on the ground and in tree layers, but only the gray leaf-eared mouse (Graomys
griseoflavus) and the desert mouse opossum (Thylamys pallidior) significantly used the
vertical space. G. griseoflavus used the arboreal space independently of habitat, plant
species or branch diameter, whereas T. pallidior showed a more selective behavior,
being present at higher heights and on large-diameter branches of Prosopis trees than
others. All rodent species used lower more than higher heights of arboreal strata. They
used heights more or only during the dry season when resource availability is low. Our
study suggests that vertical structure offers greater opportunities to acquire resources
when these are scarce and plays a role in the coexistence of small desert mammals.
Key words: arboreal activity, aridlands, marsupials, Monte Desert, rodents, scansorial,
space use, vertical strata (Soledad Albanese, Daniela Rodriguez y Ricardo Ojeda, Jour Mamm, en prensa).
Integrated analyses of chromosome, molecular and morphological variability in the Andean mice Eligmodontia puerulus and E. moreni (Rodentia, Cricetidae, Sigmodontinae)
Patterns of evolution and systematics of sigmodontine rodents are matters of continuous
revision and debate. The silky mouse, Eligmodontia, is a phyllotine rodent adapted to arid
environments. Chromosomal and molecular data have identified six species in this genus. Among these E. puerulus and E. moreni are sister taxa from the high Andean and lowland deserts respectively, with large chromosomal differences and intermediate levels of molecular divergence. The purpose of our study was to quantify the degree of variability (morphological, cytogenetic, and molecular) and to analyze its evolutionary implications within, and between, these sister species in the Monte and Puna biomes of Argentina. Our results show a high variability at the chromosomal and molecular level, but low morphological differentiation among populations of E. puerulus. Diploid numbers vary from 31 to 37 due to a complex Robertsonian system, whereas cytochrome-b distances range from 0.15% to 5.75%. On the other hand, E. moreni shows high morphological differentiation between populations,
but low intraspecific differentiation at the molecular (from 0.73% to 1.4%) and chromosomal level (2n=52). Comparison of E. puerulus with E. moreni reveals high morphological and chromosomal distinction between them, but absence of molecular differentiation. Our results suggest that: 1) the high genetic variability of E. puerulus could be associated to its geographic distribution in the complex topography of the high Andean Puna; 2) the high morphological differentiation between E. moreni and E. puerulus could be the result of natural selection; and 3) molecular polyphyly between E. puerulus and E. moreni could be due to introgression or a recent split of these taxa. Finally, our results emphasize the need to integrate different datasets in the analysis of species variability and diversification, as tools for understanding their evolutionary histories (Cecilia Lanzone, Agustina A Ojeda, Ricardo A Ojeda, Soledad Albanese, Daniela Rodriguez, Dacar Maria Ana; Mammalian Biology, 000-000; 2011).
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Niche partitioning and coexistence between two mammalian herbivores in the Dry Chaco of Argentina
Competitive interactions are known to be stronger between morphologically similar and phylogenetically
closely related sympatric species. Patagonian mara (Dolichotis patagonumMedia:652_Dolichotis_patagonum.pdf) and Chacoan cavy
(Pediolagus salinicola) are two medium-sized herbivorous mammals which have disjunctive distributions
within a sympatric region characterized by dry woodlands and shrublands (Dry Chaco, Argentina). The
niche partition hypothesis predicts that ecologically similar species living together should show differentiation
in at least one of the main niche dimensions to avoid competition. Thus, we predict that
Patagonian mara and Chacoan cavies will differentiate in the use of trophic and/or spatial niche. To prove
this hypothesis, we sampled 26 study sites in the dry and wet season and collected fresh faeces of both
species. We estimated the diet composition using microhistological analysis of faeces. For habitat
analysis we measured 16 vegetation variables, as well as habitat complexity and heterogeneity structure.
Our results showed that during the dry season, both species segregate their diet but not their habitat
niche, whereas during the wet season they segregate their habitat, and diet segregation is diffused. Diet
overlap was similar between seasons, indicating a change in the foraging strategy of the cavy, which
selected forbs, grasses, succulents and trees in the dry season and only grasses in the wet season. Our
results support the niche partition hypothesis as a mechanism of coexistence among ecologically similar
species in the South American temperate arid lands. (Verónica Chillo, Daniela Rodríguez and Ricardo A. Ojeda.2010, Acta Oecologica).
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Patterns of diversity of the Monte Desert small mammals across multiple spatial scales
The relationship between spatial scale and biodiversity patterns is a highly debated topic in ecology. We evaluated the partition of small mammal diversity at multiple spatial scales and analyzed protected areas in order to evaluate their role of protecting biodiversity at the regional scale. Diversity of small mammals in the Monte Desert was quantified at the regional biome scale (96,000 km2) (γ) and partitioned at three spatial scales: aridity range (α3,n = 6,16 000 km2), locality level (α2,n = 18,2–3 ha), and habitat patch (α1,n = 51,0.6 ha). We estimated their diversity using an additive approach with three indices (richness, Shannon-Weiner, Simpson). Diversity was higher than expected at the “between aridity range (β3)” scale, but lower at the “within-habitat scale (α1)”. Alpha was higher than beta diversity for most spatial scales; and at the regional scale protected areas preserved a higher biodiversity than unprotected ones. Our results are the first to partition the diversity of desert small mammals at multiple spatial scales and to support the hypotheses of an irregular scale dependence of alpha and beta diversity when increasing the spatial scales. They also highlight that a better understanding of biodiversity patterns is gained when several tools are integrated and combined at different spatial scales (D. Rodríguez,and R.A. Ojeda, Jour Arid Envir., in press).[260]
Food habits and impact of rooting behaviour of the invasive wild boar, Sus scrofa, in a protected area of the Monte Desert, Argentina
[261]
The wild boar, Sus scrofa, was introduced in the central region of Argentina in the early 20th century. A small feral population invaded the western area of the Man and Biosphere Reserve of Ñacuñán, Argentina in the early 1980’spdf. The purpose of our study was to provide information about the diet of wild boars in the semiarid region of Argentina and assess their potential effect on vegetation through soil rooting. We analyzed 41 faecal samples and compared cover plant composition between rooted and non rooted soil. Our results showed that 95% of the diet consisted of different parts (leaves, stems, glumes, fruits, seeds, and bulbs) of 36 plant species, while arthropods and animal tissue represented only 5% of the diet. Two plant species (Sphaeralcea miniata and Pitraea cuneato-ovata) composed the bulk of the diet, representing almost 50% of the total items found in the faeces. Plant cover was significantly different between rooted and non rooted areas. Rooted areas were dominated by Pitraea cuneato-ovata, whereas the cover of Lycium sp was higher in non rooted areas. This is the first study addressing the ecology of the wild boar in a protected area of the Monte Desert biome of Argentina. María Fernanda Cuevas, Agustina Novillo, Claudia Campos, Maria Ana Dacar and Ricardo A. Ojeda, JAE in press; partly financed by ALARM (EU)- CONICET [262]and SECYT (Argentina)[263]
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Phylogeography and genetic variation in the South American rodent Tympanoctomys barrerae (Rodentia: Octodontidae)
The red viscacha rat, Tympanoctomys barrerae, is an octodontid rodent endemic to the arid west-central and
southern regions of Argentina[[264]]. It is solitary, lives in complex burrows built in soft soil, and occurs at low
population densities in patches associated with salt basins and sand dunes in lowland habitats of the Monte[265] and
Patagonia deserts. The purpose of this study was to investigate the genetic structure and biogeography of this
desert specialist. To assess genetic variation an 800-base pair fragment of the mitochondrial control region was
sequenced for 60 individuals from 8 localities across the species’ range. Relationships among haplotypes were
inferred from phylogenetic analyses (maximum parsimony, Bayesian, and networks). Genetic structure and
demographic history were analyzed with descriptive statistics, mismatch distributions, neutrality tests (Tajima’s
and Fu’s), and analyses of molecular variance (AMOVAs). In total, 26 haplotypes were found, most restricted
to single populations. The presence of unshared haplotypes was consistent with low migration rates. Within the
distribution (between 29uS and 39uS) southern and northern populations showed higher genetic diversity values
than central populations. Populations of T. barrerae showed moderate to high genetic differentiation on the
basis of haplotypes of central populations. AMOVA analyses indicated a moderate level of geographic structure
for all populations. Low haplotype and nucleotide diversities in central populations suggest a possible
bottleneck associated with Pleistocene glaciations or volcanic activity in this part of the range of the viscacha
rat. Phylogeographic structure was moderate, and the analyses recovered 2 principal clades: A (with central and
a part of the southern distribution) and B (with northern and another part of the southern distribution). Most
populations were polyphyletic, indicating that they have not been isolated long enough to reach reciprocal
monophyly. Demographic analyses conducted for clades A and B suggest a recent history of population
expansion. (Agustina Ojeda[[266]], Journal of Mammalogy, 91(2):302–313, 2010)
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A new introduction of the European rabbit, Oryctolagus cuniculus, in northern Mendoza, Argentina
The introduction of exotic species can cause important changes in the structure and function of natural ecosystems. We report the introduction of the European rabbit, Oryctolagus cuniculus, into Villavicencio Natural Reserve in Mendoza, Argentina. Individuals were introduced from a breeding facility within the reserve. Our study assessed the possible establishment of the species as well as their potential dispersal corridors. We suggest that the rabbit could be using the riverbeds as dispersal corridors. The European rabbit, O. cuniculus, is in the establishment stage and can become a potential invader of new environments in the reserve and surrounding areas (Fernanda Cuevas, Veronica Chillo, Ariadna Marchetta and Ricardo A. Ojeda,2011, CHECKLIST, 000-000)
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New eco-morphological-behavioral approach of the chinchilla rats in the pre-Andean foothills of the Monte desert (Argentina)
This study characterizes the ecology, behaviour and morphology of populations of Abrocoma schistacea and A. uspallata in northwestern Argentina. We carried out live-trapping, tagging and recapture during 2006-2008. Burrow structure and vegetation were described. Diet composition and the activity of chinchilla rats were defined. Both species inhabit rock crevices in the pre-Andean foothills of the Monte desert. Some of their morphological specializations for saxicolous life, such as foot pads for better traction on rocky surfaces and reduced nails, are convergent with those of other saxicolous species. Both species appear to be diurnal, with activity peaking in the early morning. Dietary analyses suggest trophic specialization by both species. Density of A. schistacea was of 0.15±0.06 individuals ha-1; with individuals living in groups of 3-4 animals. Given their low abundance, restricted distribution and high level of habitat and food specialization, we urge that populations of this species be protected through effective management (Paula Taraborelli, Pablo Moreno, Paola Sassi, María A. Dacar, and Ricardo A. Ojeda. Jour Natural History, in press)
Key words: adaptations, chinchilla rats, Monte desert, saxicolous species.
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