: I agree, they are using a colloquial understanding of evolution rather than a
: biological one. I suppose it's most frustrating because other
: "science" aspects of Halo's science fiction have been reasonably
: credible, or at least based on an extrapolation from something real
: (slipspace, dyson spheres and such like). And yet when they invoke
: biological terms, they disregard their actual meaning and fall back on
: tired misrepresentations.

It's not colloquial. The Librarian's directed development towards a goal is actually more in line with the term's original usage. In fact, it may be the biological process that is misaligned with the word.

The English term prior to the late 19th century was confined to referring to goal-directed, pre-programmed processes such as embryological development. A pre-programmed task, as in a military maneuver, using this definition, may be termed an "evolution."

The term evolution (from its literal meaning of "unfolding" of something into its true or explicit form) carries a connotation of gradual improvement or directionality from a beginning to an end point.
-Good 'ol Wikipedia

And the Etymology Dictionary:
1620s, "an opening of what was rolled up," from Latin evolutionem (nominative evolutio) "unrolling (of a book)," noun of action from evolvere.

Used in various senses in medicine, mathematics, and general use, including "growth to maturity and development of an individual living thing" (1660s). Modern use in biology, of species, first attested 1832 by Scottish geologist Charles Lyell. Charles Darwin used the word only once, in the closing paragraph of "The Origin of Species" (1859), and preferred descent with modification, in part because evolution already had been used in the 18c. homunculus theory of embryological development (first proposed under this name by Bonnet, 1762), in part because it carried a sense of "progress" not found in Darwin's idea. But Victorian belief in progress prevailed (along with brevity), and Herbert Spencer and other biologists popularized evolution.

And I do believe Halsey was referring to a future of humans completely united with technology in regards to her Spartans, likely because of her research into the Forerunners and how they too reached that step. Her dislike towards Spartan IVs is not a scientific anger, but anger stemming from a mother who cared for her children and then watched them die, only to see the UNSC repeat her mistakes. The S IVs represents what she did wrong, and what she tried to undo by taking the IIs and IIIs into the Shield World on Onyx.