TPO43 integrated

The author and the lecturer both talk about a group of marine creatives, agnostids, which exist no certain theory about their way of life. The passage claims three theories about how agnosides live as free-swimming predators, seafloor dwellers, and parasites. On the other hand, the professor refutes all these theories and illustrates the weakness of each one.

First, the reading claims that agnosides may have hunted smaller organisms as free-swimming predators, and in the ocean exists lots of tiny preys for them to grazing. But the lecturer rejects this theory, saying that all kinds of predators are large and have well-developed eyes that help them to chase their prey. Therefore, agnosides can not be swimming predators as they are poor and tiny creatures that in some cases are even blind.

Seconde of all, The author goes on to mention that agnosides may were seafloor dwellers and survived on the seafloor and feeding on bacteria and dead organisms. Nevertheless, the professor rules out this theory either and mentions that agnosides are agile and quick animals while seafloor organisms don's have to move fast. Besides, seafloor creatures originated in small areas while agnosides are scattered across long distances.

Eventually, according to the passage, there is the possibility that agnosides were kind of parasites and grazing on organisms that are larger than them; however, the lecturer points out that parasites are living in small populations while agnosides had a large population. Thus, they cannot be parasites.