( ( Skin color ) ( ( is ( an ( easy ( way ( to ( ( identify ( one group ) ) ( from another ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NN Skin) (NN color)) (VP (VBZ is) (NP (DT an) (JJ easy) (NN way) (S (VP (TO to) (VP (VB identify) (NP (CD one) (NN group)) (PP (IN from) (NP (DT another)))))))) (. .)))
Skin color is an easy way to identify one group from another.
(ROOT (S (SBAR (IN Although) (S (NP (PRP it)) (VP (VBZ is) (NP (DT the) (JJS easiest) (S (VP (TO to) (VP (VB observe)))))))) (, ,) (NP (NN color)) (VP (VBZ is) (RB not) (ADJP (JJ ideal) (PP (IN as) (NP (DT a) (JJ sole) (NN way)))) (S (VP (TO to) (VP (VB identify) (NP (NNS minerals)))))) (. .)))