The most recent common ancestor of all currently living organisms is the last universal ancestor, which lived about 3.9 billion years ago. ... 6,331 groups of genes common to all living animals have been identified; these may have arisen from a single common ancestor that lived 650 million years ago in the Precambrian.
Answer:Movement makes dolphins stress which can make your insusceptible framework more vulnerable and the flare-up will spread to different dolphins and conceivably other species.
