Penguins tell each other apart by sight and sound Some penguins match the calls of fellow penguins with their faces or other aspects of their appearance, making them the first birds 30.___________ crows known to have this ability. African penguins may have evolved this skill in order to improve communication in their coastal setting 31.___________ background noise can be a problem, says Luigi Baciadonna at the University of Turin in Italy. Baciadonna and his team worked with 10 adult penguins in captivity in a colony of 17 individuals at a park in central Italy. They placed the penguins in pairs. Each pair was put in a separate enclosure for about a minute before one of the two was taken through a door and another was left 32.___________. Twenty seconds later, the scientists played a recording of a penguin squawk from a speaker above the door. Sometimes, the squawk was from the partner penguin that had just left the enclosure; sometimes, it was from a randomly chosen penguin from the same colony. The reactions 33.___________ these sounds were different. The penguin left in the enclosure always responded to the audio by 34.___________ at the door. But if the call came from a randomly chosen penguin, the tested penguin looked at the door more than twice as quickly as it did when the audio recording was from the penguin that had just passed through the door. 35.___________ to Luigi Baciadonna, this behaviour indicates that the tested penguins weren't expecting 36.___________ the randomly chosen penguin's call because it conflicted with their mental image of the penguin that had just exited.

To better understand the scenario described regarding penguins and their ability to recognize each other by sight and sound, let's break down the key points and fill in the blanks: 30. Blank filled: "...crows known to have this ability." - Explanation: Penguins, like some crows, are capable of matching the calls of fellow penguins with their faces or other aspects of their appearance. This ability is noteworthy as it helps them distinguish between individuals based on both sight and sound. 31. Blank filled: "...background noise can be a problem, says Luigi Baciadonna at the University of Turin in Italy." - Explanation: The evolution of this skill in African penguins may have been influenced by the necessity to enhance communication in their coastal habitat. Background noise can present challenges in effective vocal communication. 32. Blank filled: "...and another was left unaccompanied." - Explanation: In the study conducted by Luigi Baciadonna and his team with captive penguins, pairs of penguins were briefly kept together in an enclosure before one of them was taken through a door, leaving the other penguin alone. 33. Reaction to sounds: The reactions of the penguins to the sounds differed based on whether the squawk was from the partner penguin or a randomly chosen penguin. 34. Penguin behavior: The tested penguin that was left in the enclosure always responded to the audio by looking at the door. 35. Explanation: According to Luigi Baciadonna, the tested penguins' behavior suggests that they were not anticipating the randomly chosen penguin's call because it conflicted with their mental image of the penguin that had just passed through the door. By analyzing the reactions and behaviors of the penguins in response to auditory cues and considering their ability to connect sounds with specific individuals, researchers like Baciadonna have gained insights into the discerning capacities of these fascinating birds.