Evolution of Cellular Haemostasis

SummaryHaemostasis in primitive organisms relies on simple mechanisms of wound re-pair. During evolution, haemostasis developed in parallel with rising metabolic activity, more complex circulatory systems, and increasing size of organisms. Thrombocytes are first found in lower vertebrates. However, these cells are nucleated and derive directly from haematopoietic progenitor cells, without an interposed megakaryocyte system. Megakaryocytes are an evolutionary innovation in mammalians and human beings. Their unique system of proliferation and differentiation provided the basis for an enormous increase in the produ…