Why are Giardia and Trypanosoma not classified into the same phylum?

Giardia and Trypanosoma are not classified into the same phylum due to significant differences in their biological characteristics and life cycles. Giardia belongs to the phylum Metamonada and is primarily a flagellated protozoan that causes gastrointestinal infections in humans and animals. In contrast, Trypanosoma is classified under the phylum Euglenozoa, which includes organisms with unique features such as a kinetoplast and different modes of transmission, often involving insect vectors. These distinctions in morphology, genetics, and ecological roles justify their separation into different phyla.