When he hears the cock crowing he should say: 'Blessed is He who has given to the cock understanding to distinguish between day and night'. (Berachot 60b)
The ArtScroll siddur quotes Rabbenu Asher ben Yechiel, the Rosh, who interprets "sekhvi" as "the heart" (see Iyov 8:36), thus making the morning beracha
Blessed is He who has given the heart understanding to distinguish between day and night.
It is clear from the Talmud that this late interpretation has nothing to do with the original intention of the composer of the blessing. In a time when there were no alarm clocks, one would wake up to the crowing of the rooster. Indeed, Tehillat Hashem (the Nusach Ari / Chabad siddur) in its halachic note to the blessing states "if he was awake all night and heard the crow of the rooster after midnight, he may recite the berachah."
The Rosh lived from ca. 1250 to 1328. Wiki mentions an interesting contemporaneous fact in its article on clocks: "Between 1280 and 1320, there is an increase in the number of references to clocks and horologes in church records, and this probably indicates that a new type of clock mechanism had been devised. Existing clock mechanisms that used water power were being adapted to take their driving power from falling weights. This power was controlled by some form of oscillating mechanism, probably derived from existing bell-ringing or alarm devices. This controlled release of power - the escapement - marks the beginning of the true mechanical clock." A speculative thought is that the Rosh's reformulation arose out of his prescient awareness that the need for the rooster alarm clock would soon eliminated.
This blessing was at one time a very practical one. Today, however, it has no meaning to us without the creative rendering of Rabbenu Asher.