@SafeVarargs
		public final Builder<G, C> alterers(
			final Alterer<G, C> first,
			final Alterer<G, C>... rest
		) {
			_evolutionParams.alterers(first, rest);
			return this;
		}
The alterers used for alter the offspring population. <i>Default
values is set to {@code new SinglePointCrossover<>(0.2)} followed by
{@code new Mutator<>(0.15)}.</i>

@param first the first alterer used for alter the offspring
       population
@param rest the rest of the alterers used for alter the offspring
       population
@return {@code this} builder, for command chaining
@throws NullPointerException if one of the alterers is {@code null}.
jenetics/src/main/java/io/jenetics/engine/Engine.java