Complex sentence: Zoo animals often exhibit abnormal behaviours indicative of stress, for example, elephants perform head-bobbing, bears pace the surrounds of their enclosure, and wild cats groom themselves obsessively.
Split into simpler sentences: Zoo animals often exhibit abnormal behaviours indicative of stress. For example, elephants sometimes perform head-bobbing, bears sometimes pace the surrounds of their enclosure, and wild cats sometimes groom themselves obsessively.