( However ( , ( ( when ( ( ( the scarcity ) ( of ( food sources ) ) ) ( cause ( ( individual cells ) ( to starve ) ) ) ) ) ( , ( ( ( roughly 10 ) ( ^ ( ( ( 4 to ) 10 ) ( ^ ( 5 cells ) ) ) ) ) ( ( aggregate ( to ( form ( ( a ( mobile ( , ( multicellular structure ) ) ) ) ( dubbed ( a ( `` ( slug '' ) ) ) ) ) ) ) ) . ) ) ) ) ) )
(ROOT (S (ADVP (RB However)) (, ,) (SBAR (WHADVP (WRB when)) (S (NP (NP (DT the) (NN scarcity)) (PP (IN of) (NP (NN food) (NNS sources)))) (VP (VBP cause) (S (NP (JJ individual) (NNS cells)) (VP (TO to) (VP (VB starve))))))) (, ,) (NP (QP (RB roughly) (CD 10)) (JJ ^) (QP (CD 4) (TO to) (CD 10)) (JJ ^) (CD 5) (NNS cells)) (VP (VBZ aggregate) (S (VP (TO to) (VP (VB form) (NP (NP (DT a) (JJ mobile) (, ,) (JJ multicellular) (NN structure)) (VP (VBN dubbed) (NP (DT a) (`` ``) (NN slug) ('' '')))))))) (. .)))
However, when the scarcity of food sources cause individual cells to starve, roughly 10^4 to 10^5 cells aggregate to form a mobile, multicellular structure dubbed a “slug”.
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NN food)) (VP (VBZ is) (ADJP (JJ scarce))))) (, ,) (NP (VBG starving) (NNS cells)) (VP (VBP secrete) (NP (NP (DT a) (NN molecule)) (SBAR (WHNP (WDT that)) (S (VP (VBZ stimulates) (NP (VBG neighboring) (NNS cells)) (PP (TO to) (NP (NN aggregate)))))))) (. .)))