The origin and diversification of eukaryotes: problems with molecular phylogenetics and molecular clock estimation
نویسندگان
چکیده
منابع مشابه
The origin and diversification of eukaryotes: problems with molecular phylogenetics and molecular clock estimation.
Determining the relationships among and divergence times for the major eukaryotic lineages remains one of the most important and controversial outstanding problems in evolutionary biology. The sequencing and phylogenetic analyses of ribosomal RNA (rRNA) genes led to the first nearly comprehensive phylogenies of eukaryotes in the late 1980s, and supported a view where cellular complexity was acq...
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the evaluation of language related engagment and task related engagment with the purpose of investigating the effect of metatalk and task typology
abstract while task-based instruction is considered as the most effective way to learn a language in the related literature, it is oversimplified on various grounds. different variables may affect how students are engaged with not only the language but also with the task itself. the present study was conducted to investigate language and task related engagement on the basis of the task typolog...
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ژورنال
عنوان ژورنال: Philosophical Transactions of the Royal Society B: Biological Sciences
سال: 2006
ISSN: 0962-8436,1471-2970
DOI: 10.1098/rstb.2006.1845