Related by context. Frequent words. (Click for all words.) 61 speculated 55 speculate 53 argue 51 say 50 believe 48 theories 45 speculating 44 theory 42 wondered 42 suggest 42 contend 41 hypothesis 41 guessed 41 wonder 41 thought 40 presume 39 believed 39 warn 39 allege 39 argued 38 know 38 guess 38 predict 38 suggested 37 wondering 37 fear 37 clue 37 explain 36 figured 36 unclear 36 suggesting 36 probably 35 clues 35 puzzled 35 attribute 35 worry 35 feared 35 think 35 ponder 34 evolutionary 34 unsure 34 perceive 34 puzzling 34 suspect 34 myth 34 mystery 34 actually 34 apparently 34 assumed 33 arguing 33 determine 33 cite 33 complain 33 conclude 33 presumed 33 naturally 33 contended 33 guessing 33 notion 33 mysteries 33 pinpoint 32 opined 32 reckon 32 understand 32 explained 32 convinced 32 argues 32 realize 32 insist 31 worried 31 tell 31 assume 31 acknowledge 31 baffled 31 suspicions 31 talk 31 explains 31 fret 31 assert 31 suggests 31 doubted 30 myths 30 believing 30 suppose 30 contends 30 curious 30 theoretically 30 argument 30 predicted 30 pretend 30 fearful 30 humans 30 discovered 30 induced 30 expressed concern 30 wonders 30 tease 30 claim 30 reasoned 29 puzzle 29 seem