The signs that earthquakes may occur is.. Foreshocks, Changes in temperature, and Magnetic properties of rocks, Animal behavior,
Paper, pencils, spoons, trash cans, etc
There are different types of observers. Casual observers differ from scientific observer. Seeing and observing are two different things. Not that everybody seeing is actually observing the thing.
A casual observer just sits back and watch for something to happen while a scientific observer comes up with some hypothesis to work on it.
The process where a specie develops and evolves into new many species is termed as speciation. Macroevolution explores the mechanism of speciation where organisms across biological populations evolve as distinct population.
There are many causes to speciation, a) geographic isolation, b) gene flow reduction, and c) reproductive isolation.