Erythrocytes, neurons, skeletal cells, and columnar cells are examples of: specialized cells.
A population with a lot of genetic variation would likely have more phenotypic variation; therefore, such a population would more likely have individuals that can adapt to a changing environment. mutation can result in new alleles on chromosomes. ... this is the same effect that genetic drift can have on small populations.
Yes, classification system is still evolving together with our knowledge.
But, before changing the name (e.g. of a species) it is important to collect and gather a wealth of information in order to support that change. Classification system is still evolving. The reasons for the changes are DNA analyzes. It is the new way for discovering relation between organisms and put them in the right context (classification used to be based on morphological characteristics).
Change in classification can be shown in an example of fungi. In the 90s fungi classification included only phyla Chytridiomycota and Zygomycota. Now theyhave been classified mainly on the basis of characteristics of their sexual reproductive structures. So, there are 7 phyla now: Microsporidia, Chytridiomycota, Blastocladiomycota, Neocallimastigomycota, Glomeromycota, Ascomycota, and Basidiomycota
PH Level, and food source such as sugar.