The systematics of the dusky striped squirrel, Funambulus sublineatus (Waterhouse, 1838) (Rodentia: Sciuridae) and its relationships to Layard's squirrel, Funambulus layardi Blyth, 1849

The systematics of the dusky striped squirrel, Funambulus sublineatus (Waterhouse, 1838) are reassessed against new evidence following a revision of its genus, Funambulus Lesson, 1835. Mitochondrial DNA suggests that the Sri Lankan subspecies of F. sublineatus is the sister taxon of F. layardi Blyth, 1849, despite its phenotypic similarity to the nominate species. Morphological and mtDNA evidence is presented for these species plus additional mtDNA data from F. palmarum (Linnaeus, 1766) and F. pennantii Wroughton, 1905. Morphometric data indicate that the two taxa conventionally considered subspecies of F. sublineatus are sufficiently distinct for them to be ranked separately, resulting in two further endemic mammal species in India and Sri Lanka and an increase in Funambulus diversity. The name of the Sri Lankan species changes to Funambulus obscurus (Pelzeln and Kohl 1886). Whether the mtDNA phylogeny is a true reflection of F. obscurus and F. layardi remains unresolved pending further data

Do Siberian Flying Squirrels reuse nest materials made by other individuals?

Arboreal small mammals nesting in tree hollows usually line nests with materials such as leaves and shredded bark. Pteromys volans orii (Siberian flying squirrel), an endemic subspecies to Hokkaido, Japan, uses shredded bark. Since their nest materials have a very consistent shape, we suspect the squirrels use much effort to collect and shred the bark. To save effort, they may reuse nest materials made by other individuals. To test this, we mixed artificial nest materials (coloured cotton strings) into nest materials and observed the transfer of strings among nests. Of 39 nest boxes seeded with coloured cotton strings, number of strings decreased in 25 boxes (64.10%). Strings from 12 boxes were moved to other boxes. In addition, we found that P. volans orii possibly reused nest materials prepared by other individuals. Both nests and nest materials may be important re-useable resources for P. volans orii

Geographic isolation created distinct pelage characters in Finlayson’s squirrel on isolated island offshore of the Indochina Peninsula in Central Vietnam

We found distinct pelage characters in Finlayson’s squirrel (Callosciurus finlaysonii) population, which is endemic to Lao Island of the Cham Islands, located off the coast of central Vietnam. Among squirrels of the ‘C. erythraeus-finlaysonii complex’, which consists of all forms of C. erythraeus and C. finlaysonii, mitochondrial cytochrome-b sequences show that the Lao Island squirrel forms a cluster with C. finlaysonii with external characters of C. erythraeus flavimanus, defined previously as ‘C. finlaysonii morpha flavimanus’. Both squirrel forms, however, differed in pelage colour. This different colouration may have arisen from the effect of geographic isolation

Phylogenetic relationships among Callosciurus squirrels in the Indochina Peninsula: phylogenetic position of C. pygerythrus from Myanmar

The phylogenetic relationships among seven Callosciurus species from the Indochina Peninsula, including the C. honkhoaiensis which is endemic to Hon Khoai Island, were studied using complete mitochondrial cytochrome b gene sequences (1140 bases). We primarily focused on the phylogenetic position of C. pygerythrus, which is distributed in the western part of the peninsula. We identified two main lineages: 1) C. caniceps, C. honkhoaiensis, C. inornatus, C. phayrei and C. pygerythrus, and 2) C. erythraeus and C. finlaysonii. Estimated divergence time between the two lineages was at the junction of the Zanclean and Piacenzian in the Pliocene. Within the first linage, the divergence time of sub-lineages corresponded to the Pliocene-Pleistocene boundary, although phylogenetic relationships were unclear. These two divergence times estimated in the present study correspond to episodes of global cooling, suggesting that climate may have contributed to the divergence of these Callosciurus squirrels

Is there an evolutionary relict of the Japanese giant flying squirrel Petaurista leucogenys on the Asian Continent?

El impacto de una especie invasora se relacionea con su grado de novedad funcional rrespecto de la comunidad residente.. En esta tesis se propuso que la invasión de árboles exóticos en pastizales genera una cascada de efectos que involucran distintos niveles de organización, desde la demografía de las poblaciones herbáceas y la composición funcional del pastizal hasta atributos del ecosistema como la productividad primaria y la fertilidad del suelo.. Además, se anticipó que estos efectos se intensificarían a lo largo de gradientes naturales de invasión.. Se realizaron estudios observacionales y experimentales en dos pastizales post - agrícolas de la Pampa Interior invadidos alternativamente por Gleditsia triacanthos (acacia negra) o Ulmujs pumila (olmo siberiano).. Mediante censos de vegetación se observó que con el avance de la invasión desaparecieron del estrato herbáceo las especies perennes estivales e invernales.. En el caso de acacia, las especies anuales de invierno fueron favorecidas en estadíos intermedios de invasión pero decrecieron en los bosques más densos.. La productividad primaria neta aérea (PPNA) herbácea disminuyó con la invasión de árboles.. En los estadíos más avanzados de invasión de acacia y olmo se detectaron una reducción del carbono orgánico y un aumento de la alcalinidad superficial del suelo, respectivamente.. Experimentos de remoción de broza limitó el reclutamiento de herbáceas en estadios iniciales de la invasión, mientras que favoreció el reclutamiento de Lolium multiflorum en etapas intermedias de la invasión.. En cambio, en el sitio invadido por olmo, el reclutamiento de esta especie no fue afectado por la presencia de broza, pero aumentó con el agregado de semillas. Se analizó el rol de la luz como modulador de los efectos sobre la comunidad herbácea mediante un experimento de simulación del sombreo arbóreo combinado con transplantes recíprocos de parches de pastizal y de bosque.. El sombreo aumentó la cobertura de las especies anuales invernales, mientras que las especies perennes estibales mostraron cierta inercia en su respuesta al ambiente.. Los resultados de esta tesis muestran que los árboles exóticos actúan como ingenieros del ecosistema, afectando los ervicos que los pastizales secundarios proveen en los agroecosistemas

A note on karyotypes of Sorex caecutiens (Mammalia, Insectivora) from Cheju Island, Korea

Karyotypes of Sorex caecutiens from Cheju Island of Korea were examined with conventional staining and G-banding by trypsin treatment stained with Giemsa (GTG). The diploid and fundamental autosomal arm numbers were 42 and 66, respectively. The autosomal complement in the karyotype comprised six pairs of metacentrics, seven pairs of submetacentrics or subtelocentrics, and seven pairs of acrocentrics. The X was a largest acrocentric chromosome, and the Y was a small subtelocentric chromosome. Chromosomal constitutions and G-banding pattern of S. caecutiens from Cheju Island were essentially identical to those reported for S. shinto from Honshu Island, Japan. This similarity may indicate the ancestral character of the monophyletic S. caecutiens/shinto group

Banded karyotypes of the Persian squirrel Sciurus anomalus from Turkey

WOS: 000258126400005Karyotypes of seven males and three females of the Persian squirrel, Sciurus anomalus, were analyzed with G- and C-banding techniques and Ag-NOR (nucleolus organizer region) staining. All specimens had the diploid number (2n) of 40 and fundamental autosomal arm number (FN) of 76. The autosomal complement comprised 6 pairs of metacentrics and 13 pairs of submetacentrics. The X chromosome was a medium-sized metacentric. The Y chromosome was a small submetacentric. In the C-banded karyotype, except for centromeric heterochromatin, heterochromatin blocks were absent. Only the terminal region of one medium-sized metacentric pair had detectable Ag-NORs. The uniqueness of the chromosomal characteristics of S. anomalus suggests that S. anomalus is distantly related to the other Old World Sciurus species (S. lis and S. vulgaris)