Independent origins of parasitism in Animalia.

Abstract in brief

• Parasitism has independently evolved at least 223 times across 15 different animal phyla, predominantly within Arthropoda, indicating multiple origins rather than a single evolutionary event.
• The study shows that while parasitism is mostly studied in helminths, numerous independent parasitic groups also exist in Mollusca, Rotifera, Annelida, and Cnidaria, with nearly no occurrence in deuterostomes.
• Although parasitic groups often have similar potential for speciation as free-living species, a small number of large parasitic clades account for the majority of parasitic animal diversity, highlighting their significant role in the overall diversity of animal life.]