“It is certain that there may be extraordinary activity with an extremely small absolute mass of nervous matter; thus, the wonderfully diversified instincts, mental powers, and affections of ants are notorious, yet their cerebral ganglia are not so large as the quarter of a small pin’s head. Under this point of view, the brain of an ant is one of the most marvelous atoms of matter in the world, perhaps more so than the brain of man.” ~ Charles Darwin in 1871
Sahara Desert Ant
“The ability to assess the informational value of landmarks or trails as relevant or irrelevant is another example of the amazing cognitive performance of the tiny ant brain.” ~ Roman Huber
The Sahara desert ant inhabits the searing salt pans of Tunisia. Hardly any other animal survives in this scorching wasteland.
The ants shelter in subterranean nests. To forage for food, desert ants go out on their own, spending entire days wandering far from the nest. A scavenging ant may chance upon a small corpse: an arthropod which got blown by the wind to die from exposure in this hell; a bit of luck from the unlucky. The problem then becomes taking the prize back home.
Wondrous mathematical navigators, desert ants use the Sun as a compass, and count their steps. But, having traveled far, this is not enough to navigate the barren badlands and get back to the nest; so, landmarks – whether visual, olfactory, vibrational, or magnetic – are relied upon. Therein is another dilemma. Some cues are reliable, others not. Desert ants wisely discriminate between those hints they may depend upon and those which may send them astray. Reliable cues are often a certain combination of indications, which must be remembered within the context of a vast mental map that accurately explains the terrain.
“Ants not only pinpoint their nest by following learned cues, they also take into account which cues uniquely specify the nest and which, due to their ubiquity, are less informative, and so less reliable.” ~ German chemical ecologists Roman Huber & Markus Knaden