What is "all the less"

Usage examples of "all the less".

And all the less advanced creatures were just as susceptible to the cyanogens as were humans, Cardassians, and other invaders: they simply lived such a short time that most died of other causes long before the contaminants could kill them.

Imaginary ailments were as far from her life as the surface of the moon, and that made Jamie Murchison's remarks all the less credible.

And all the less ad- vanced creatures were just as susceptible to the cyanogens as were humans, Cardassians, and other invaders: they simply lived such a short time that most died of other causes long before the contami- nants could kill them.