Ok i got that point, so i can reshape my initial question, checking below sites link and link when a species diverge into 2 new species, does it mean that the ancestor that diverges extinct ?

@Remi.b I have just started by watching the video you have mentioned in your post "If you want to know why I am using term 'lineage' rather than 'species', you can have a look at this post" and there is a video in the end of that post named "What Makes a Species a Species?" and i have watched in ending says biological species concept is not an absolute rule

Thank you for the very descriptive answer, as you have figured out easily I am very new to evolution. I will read the references you have provided carefully, but I think the main answer to my question is after evolution of a specie through natural selection, unfit ancestor extinct and this is explained through phylogeny ?

Thanks for the answer and showing the related question, I specifically didn't want to give an example like apes to humans evolution but the evolution that happened during the times when the life has begun. Could it be that life has started in different locations and in one habitat mutations that were favorable to survive through selection were not necessarily the fittest in another habitat and the same species was already fit to survive and mutations that lead to new species were not the fittest in that location?