Murine rodents are excellent models for study of adaptive radiations and speciation. Brown Norway rats (Rattus norvegicus) are successful global colonizers and the contributions of their domesticated laboratory strains to biomedical research are well established. To identify nucleotide-based speciation timing of the rat and genomic information contributing to its colonization capabilities, we a...

the reptile and mammals fauna of north-east of iran were investigated and the contraction and fragmentation of some species due to climatic changes and human activities were analyzed. the sampling was carried out in selected stations throughout the great khorsan. the results showed that there are approximately 71 reptiles (including 39 species of lizards, 32 snakes and one turtle) and 83 specie...

the altitude to which the past glaciers had been extended during the last glacial period in dinevar basin, western iran, can be estimated based on glacier-geomorpic evidence such as cirques, u-shaped valleys, and the moraines in lowlands. this study estimates the elevation of snowline during this period for the basin as the objective of the research. topographic and geologic maps, landsat image...

Geological and climatic processes potentially alter speciation rates by generating and modifying barriers to dispersal. In Southeast Asia, two processes have substantially altered the distribution of land. Volcanic uplift produced many new islands during the Miocene-Pliocene and repeated sea level fluctuations during the Pleistocene resulted in intermittent land connections among islands. Each ...

Crater degradation on Mars is a key to understand erosion through time. Strongly eroded craters in the highlands are interpreted to be the result of enhanced erosion rate during the Noachian epoch [1]. While fluvial valleys climatic meaning and duration are still difficult to define (strongly warmer climate or episodic activity under slightly warmer climate), the enhanced Noachian craters degra...