Meanings of sharp demarcation in English

Between men and apes there exists a line of sharp demarcation.

At the outset, there is no sharp demarcation of useful, or industrial, arts and fine arts.

There is no sharp demarcation between dry-and humid-farming.

Of course it may readily be acknowledged that this method does not allow a sharp demarcation line between its various factors.

In morals it takes the form of a sharp demarcation of the motive of action from its consequences, and of character from conduct.

Upon the philosophical side, these various dualisms culminate in a sharp demarcation of individual minds from the world, and hence from one another.

Where most objects in space show a sharp demarcation between sunlight and shadow, the cylindrical craft glowed all over, as though from some inner light.