qT=1&tQ=The smallest baboon is the...&tC=Guinea Baboon.|Olive Baboon.|Yellow Baboon.|Chacma Baboon.&cC=1&fB=The smallest baboon is the Guinea baboon, measuring about 20 inches in height and weighing only 14 lbs.<br><br>The largest and heaviest baboon is the Chacma Baboon, which is about 45 inches and weighs 90 lbs. Mandrills and Drills are larger animals but are technically not baboons, although they are closely related.