Two related theories of hematopoiesis; which is widely accepted, and what does it suggest?

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All blood cells are thought to come from one pluripotent hematopoietic stem cell, giving rise to all lineages in a unified developmental plan. This view, the monophyletic theory, holds that a single stem cell in the bone marrow differentiates through multipotent progenitors into both myeloid and lymphoid lineages, producing red cells, platelets, granulocytes, monocytes, and lymphocytes. The strength of this idea comes from functional studies showing that a single stem cell can reconstitute multiple blood lineages after transplantation and from lineage tracing that reveals a common origin for diverse cell types. In contrast, a polyphyletic view would require multiple separate stem cell sources for different lineages, which is not supported by the clonal relationships observed across lineages. So the widely accepted concept is that all blood cells originate from a single pluripotent stem cell, highlighting a shared origin for the entire hematopoietic system.