© June Hunter
Crows are known for play behavior, a marker for intelligence
The intelligence of corvids like ravens and crows is well known. Recently, crows were even shown to have a numerical ability seen in few other species so far: a grasp of the concept of the empty set — the numerosity zero.
An understanding of numbers is often viewed as a distinctly human faculty — a hallmark of our intelligence that, along with language, sets us apart from all other animals.
But that couldn't be further from the truth. Honeybees
count landmarks when navigating toward sources of nectar. Lionesses
tally the number of roars they hear from an intruding pride before deciding whether to attack or retreat. Some ants
keep track of their steps; some spiders
keep track of how many prey are caught in their web. One species of frog bases its entire
mating ritual on number: If a male calls out — a whining
pew followed by a brief pulsing note called a chuck — his rival responds by placing two chucks at the end of his own call. The first frog then responds with three, the other with four, and so on up to around six, when they run out of breath.
Comment: Uncommon Descent also noted Peterson's reactions to the God Hypothesis: