Species formation without branching of the evolutionary line of descent is called as:
1. anagenesis, or phyletic evolution
2. cladogenesis, or divergent evolution
3. convergent evolution
4. allopatry

According to the modern view of Darwinism, the unit of natural selection is the :
1. population
2. individual
3. species
4. community

In recent years, DNA sequences (nucleotide sequence) of mtDNA and Y chromosomes were considered for the study of human evolution, because             
1. they are small, and therefore, easy to study
2. they are uniparental in origin and do not take part in recombination
3. their structure is known in greater detail.
4. they can be studied from the samples of fossil remains.