Lizards exhibit behavioral flexibility, using multiple strategies and reversal learning, plus rapid associative learning. This degree of flexibility is not predicted for a species that lacks complex social structure and has a relatively simple foraging strategy (i.e., sit-and-wait). ~ American zoologists Manuel Leal & Brian Powell
Many studies of reptile cognition in the 1950s and 1960s were inherently flawed, as they had been designed for mammals, which have different reactions to stimuli. With an accumulation of negative results from obtuse researchers, reptiles were generally considered dim-witted. The irony of scientific stupidity is unending.
In the 1960s, American neurobiologist Paul MacLean fantasized that the human brain had 3 levels: a triune brain. The lowest was the reptilian complex, followed by the limbic system, with the neocortex on top. This sophistic notion carried currency in some corners, particularly psychiatrists (not the brightest flock of psychologists), but never gained acceptance among thoughtful zoologists.
American science writer Carl Sagan imprudently popularized the triune human brain in his 1977 Pulitzer Prize-winning book: The Dragons of Eden. The Pulitzer Prize awarded was not given for fiction, which Sagan’s book was. Thanks to Sagan’s prosaic tripe, the notion of a reptilian part of the human brain is still popularly believed.
The sine qua non of intelligence is survival. Most lizards are well camouflaged in their natural surroundings and know to keep still until a predator passes by. With the ability to change their look, chameleons are especially careful to blend in to their location when danger is sensed.
Other lizards distract or startle a predator to give themselves a chance to escape. The Australian frilled lizard, for instance, opens its big mouth, loudly hisses, and flashes its expansive neck frill before scampering away.
Though lizard savvy has not been studied extensively, lizards are at least as clever problem solvers as social birds, such as those in the Paridae family, which includes tits and chickadees.
Monitor lizards are among the smartest of lizards. They can count at least up to 6, which is likely as high as they’ll ever need to count.
Monitors are adapted for hunting live prey. They have a venomous bite. 2 or more may hunt together cooperatively.
One monitor was observed luring away a female crocodile from her nest while its partner opened the nest to feed on the eggs. The decoy was then given its chance to an egg feast.
Sociality demands mental acumen in keeping track of relationships. Lizards are gregarious.