( ( If ( that ( ( ( were ( the case ) ) , ) ( breeding him ) ) ) ) ( ( ( might well ) ( ( pass ( that trait ) ) ( on ( to ( his offspring ) ) ) ) ) . ) )
(ROOT (S (SBAR (IN If) (S (NP (DT that)) (VP (VBD were) (NP (DT the) (NN case)) (, ,) (S (VP (VBG breeding) (NP (PRP him))))))) (VP (MD might) (ADVP (RB well)) (VP (VB pass) (NP (DT that) (NN trait)) (PP (IN on) (PP (TO to) (NP (PRP$ his) (NN offspring)))))) (. .)))
If that were the case, breeding him might well pass that trait on to his offspring.
(ROOT (S (NP (JJ Selective) (NN breeding)) (VP (VBZ involves) (S (VP (VBG choosing) (NP (JJ certain) (NNS organisms)) (S (VP (TO to) (VP (VB reproduce) (PP (IN with) (NP (CD one) (DT another))) (SBAR (IN in) (NN order) (S (VP (TO to) (VP (VB pass) (PP (IN on) (NP (JJ specific) (, ,) (JJ desirable) (NNS traits))) (PP (TO to) (NP (PRP$ their) (NN offspring))))))))))))) (. .)))
Selective breeding involves choosing certain organisms to reproduce with one another in order to pass on specific, desirable traits to their offspring.