Chapter 8 flashcards _ Quizlet

Alth o u g h farmersh av eco n tin u ed to selectfo

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Unformatted text preview: ap ed in th e p ast u n d er co n d itio n s th at d iffered fro m th o se in th e p resen t. Artificial selectio n was u sed o n co rn to p ro d u ce a sin g le strain o f co rn with in creased g ro wth rates an d g reater resistan ce to a fu n g u s. Alth o u g h farmers h av e co n tin u ed to select fo r th ese traits, th e p ro d u ctiv ity o f th is strain is n o lo n g er in creasin g . Th is su g g ests th at: all o r mo st o f th e n atu ral v ariatio n fo r th ese traits h as b een elimin ated . . In a p o p u latio n in wh ich a trait is ex p o sed to stab ilizin g selectio n o v er time: Stab ilizin g p ressu re selects fo r an in termed iate trait g ettin g rid o f th e "o u tliers". Th e av erag e, h o wev er, stay s th e same. Th is p ressu re also selects fo r o n e "av erag e" trait, d ecreasin g v ariatio n . Sectio n 8 .1 5 Maze­ru n n in g b eh av io r in rats: is a h eritab le trait. Th is b eh av io r is g en etic an d can b e p assed o n . Sectio n 8 .1 6 A fo ssil is d efin ed mo st b ro ad ly a s: an y p reserv ed remn an t o r...
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This document was uploaded on 02/25/2014.

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