Describe the adaptability of invertebrates to a parasitic lifestyle.

Invertebrates are morphologically and behaviorally very similar to the parasite’s lifestyle. Although there are only two strains of exclusively parasitic species, some subspecies have evolved over several generations from free to parasitic organisms. Such changes depend on how much a particular invertebrate is already prepared for the parasitic lifestyle (high heat resistance, low oxygen consumption, etc.). Parasitic species use special reproductive strategies. Females produce an extremely large number of eggs (80 to 300 million per year). In addition, some parasites have multiple hosts.