Is-ought fallacy (Hume's guillotine)

Biological Parallel

Describing parental investment patterns in Pacific salmon (semelparous death after spawning, complete resource transfer to offspring) doesn't prescribe human reproductive ethics. Observing kin selection in ant colonies (workers sacrificing reproduction to raise sisters) doesn't justify nepotism in hiring decisions. The "is" of biological mechanism provides no logical bridge to the "ought" of normative behavior without importing values from outside biology. Evolution explains; it doesn't justify.