Platyhelminthes
Platyhelminthes are flatworms that are simple bilaterian, unsegmented, soft-bodied invertebrates. They are commonly known as flatworms which include such organisms as tapeworms and flukes. Over 80% of the population of flatworms on Earth are parasitic, which means that they in or on another organism.
History
Not much is known about how old phatyhelminthes are because they do not contain any perserveable body parts such as bones. Scientists today believe that the first turbellarians evolved around 550 MYA (million years ago). Today there are about 20,000 known species of Platyhelminthes.
Platyhelminthes are flatworms that are simple bilaterian, unsegmented, soft-bodied invertebrates. They are commonly known as flatworms which include such organisms as tapeworms and flukes. Over 80% of the population of flatworms on Earth are parasitic, which means that they in or on another organism.
History
Not much is known about how old phatyhelminthes are because they do not contain any perserveable body parts such as bones. Scientists today believe that the first turbellarians evolved around 550 MYA (million years ago). Today there are about 20,000 known species of Platyhelminthes.