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1

Genetic variability of small isolated populations of Cicerbita alpina (L.) Wallr. (Asteraceae) in the Beskid Mały Mts (Southern Poland)

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Stachurska-Swakon A., Cieslak E., Ronikier M.
Polish Journal of Ecology
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2011
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tom 59
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nr 2
The populations of Cicerbita alpina in the Beskid Mały Mts. (Western Carpathians, Poland) are the northernmost, spatially isolated localities of this subalpine tall-herb species in the Carpathians. The genetic structure of these populations was studied using the AFLP method. The analysis also included the populations of the larger, more population-abundant parts of the distribution range to the north (Scandinavia) and to the south (the Tatra Mts., Western Carpathians). The genetic similarity of the Beskid Mały populations with those from the Tatra Mts. and Scandinavia was relatively low and the populations formed geographically distinct genetic groups. The populations from the Beskid Mały Mts. Were characterised by lower genetic variation, as well as the lowest degree of genetic differentiation (nie and Shannon’s coefficients), compared with those from the Tatra Mts. and Scandinavia. Our results indicate a relatively long period of isolation of the Beskid Mały Mts. populations; there is no evidence for recent dispersal or extant gene flow with populations from other regions. The differences among the populations also testify to fixation of genes in isolated areas, probably traced back to the founder individuals.
2
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Biodiversity and habitat assessment of Mount Malindawag, Naawan, Misamis Oriental, Philippines

100%
Castanares E. D., Vedra S. A., Gorospe J. G.
International Letters of Natural Sciences
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2017
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tom 62
Habitat fragmentation results to displacement of inhabiting floral and faunal species. The resulting geographic isolation of various species affect regeneration, genetic flows and recruitment. Hence, a study was conducted in a forested area of Mt. Malindawag in Naawan, Misamis Oriental. Sampling stations were designated at the agro-forest, mid-forest and upper-forest habitat types. Species characterizations were based on DAO 2007-01 and IUCN Red List for conservation status. Results showed highest diversity index of flora at mid-forest while lowest diversity was observed in the agro-forest area. A tree species Canarium racemosum obtained highest Species Importance Value (SIV) at 38.6%, 42% and 30.8%, respectively in the three habitat types. The highest endemicity of flora was at mid-forest with 24% per DAO 2007-01 and 26% per IUCN conservation status. Majority of faunal species were birds that were mostly resident and common and were usually observed at upper-forest habitat. The relatively low diversity and endemicity of flora and fauna species could be due to the influx of human population. Various activities undertaken were threatening the inhabiting biodiversity, and therefore, demand immediate protection and conservation measures from formulating policies to increasing awareness of various stakeholders. Future related studies were recommended to increase scientific understanding on the interrelationships of socio-economic and ecological interactions of biodiversity to the inhabiting human population.
3

Ctenomys lami: The highest chromosome variability in Ctenomys [Rodentia, Ctenomyidae] due to a centric fusion-fission and pericentric inversion system

100%
Freitas T. R. O.
Acta Theriologica
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2007
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tom 52
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nr 2
Ctenomys lami Freitas, 2001 is an endemic species of rodent inhabiting the Coastal Plain of southern Brazil, along a narrow line of old dunes formed in the Pleistocene. This species has five different diploid numbers (2n=54, 55a, 55b, 56a, 56b, 57 and 58) and ten different autosomal fundamental numbers (FNa=74, 75, 76, 77, 78, 79, 80, 81, 82, and 84). In a sample of 102 specimens, the combined 2n and FNa formed 26 different karyotypes. The diploid number variation was due to Robertsonian rearrangements that occur in pairs 1 and 2, and the variation of NFas was due to pericentric inversions. The distribution of diploid number variation along the 78 km line of collection sites reveals four population blocks: block A with 2n=54, 55a, and 56a; block B with 2n=57 and 58; block C with 2n=54 and 55a; and block D with 2n=56b and 55b. The inversion system lacks geographic structure with a random distribution of inversions along the population blocks. A very narrow hybrid zone is hypothesized between blocks A and B. Blocks B and C are separated by a geographic barrier, and another hybrid zone is found between blocks C and D. My findings suggest that this species is undergoing a process of speciation due to geographic isolation.
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