Biology / Unit 10 Bio 2229 short lesson, about 20 seconds
Evolutionary Complexity Has No Direction
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The idea
Natural selection, per Bio 0055, favors traits fitting a lineage's environment; it sets no complexity goal, and simple traits often persist because they work.
In practice
A tapeworm's simplified body, lacking a digestive system, is a derived adaptation to its niche, not an unevolved state.
Where people slip
"Plants are simpler than animals," per Bio 2227, assumes a rank order evolution does not produce.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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