The correct answer is Mollusks, Echinoderms, Chordates, and Annelids.
This is basically how evolution works, at a certain point in the past,
there was a transitional organism that eventually developed into
roundworms and the other part of his species that was exposed to other
things evolved into other transitional organisms who evolved eventually
into these 4 groups.
<span>The abundance and variety of fossils in Phanerozoic rocks have allowed geologists to decipher in considerable detail the past 600 million years or so of the Earth’s history. In Precambrian rocks, however, fossils are rare; thus, the geologic record of this important part of the Earth’s history has been especially difficult to decipher. Nonetheless, stratigraphy and radiometric dating of Precambrian rocks have clearly demonstrated that the history of the Earth extends billions of years into the past.</span>
Nice shift is the change in behavioral or feeding patterns by two or more competing populations to reduce interspecific competition. Interspecific competition is a type of competition between organisms of different species. A niche is a full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions.
