In a mutational event, when adenine is replaced by guanine, it is a case of -

Age of fossils in the past was generally determined by radio-carbon method and other methods involving radioactive elements found in the rocks. More precise methods, which were used recently and led to the revision of the evolutionary periods for different groups of organisms includes -

What kind of evidence suggested that man is more closely related with chimpanzee than with other hominoid apes ?

According to oparin, which one of the following was not present in the primitive atmosphere of the earth ?