Song and appearance both play a role in keeping different species from mating.
Chat with our AI personalities
solid
All I know is that he love to collect species and look at their physical characteristic so that he could come up with a more describable way of classification of each and every living species on earth. Also he look at how species differ from the other and this is where he came up the theory that species evolve from the same ancestors and keeps on evolving as time changes.
gravity keeps us in a circle
sprinkler
The sun's gravitational pull keeps the earth in orbit around it.