What problems would upu expect to observe in an ecosystem without secondary consumers

If secondary consumers are removed from the ecosystem, an ecological imbalance may be created. Secondary consumers are generally feed on other animals (primary consumers) Thus, on removing secondary consumers from food chain, there will be increase in population of primary consumers as a result all the grass and other vegetation will be eaten by the primary consumers. This will leads to desertification and eventually all the top consumers will also eliminated from the ecosystem.

the supermassive black hole is in the middle of the galaxy.

the fossil record provides evidence of a common ancestor to many species.