lecture 8 studyguide - soical behaviours.pdf

1 Corvids, belonging to the family Corvidae, encompass a diverse group of medium to large-sized birds, including crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers. These birds are found worldwide, except for the southern tip of South America and the polar ice caps. Th...

1 Corvids, belonging to the family Corvidae, encompass a diverse group of medium to large-sized birds, including crows, ravens, rooks, jackdaws, jays, magpies, treepies, choughs, and nutcrackers. These birds are found worldwide, except for the southern tip of South America and the polar ice caps. They are omnivorous, with diets consisting of various food sources such as invertebrates, nestlings, small mammals, berries, fruits, seeds, and carrion. Some corvids, particularly crows, have adapted well to human environments and have come to rely on human food sources, thriving in urban and suburban areas. How 2 Measuring intelligence in animals involves various methods, including the mirror test, tool use, and brain-to-body mass ratio. The mirror test assesses an animal's selfawareness by observing its reaction to a mark placed on its body while looking in a mirror. Tool use involves the use of physical objects to extend an individual's ability to modify features of the surrounding environment or accomplish tasks. Brain-to-body mass ratio compares the size of an animal's brain relative to its body size, although it may not always accurately reflect intelligence. 3 Corvids, such as the Eurasian Magpie and the Indian House Crow, have demonstrated self-recognition in the mirror test, making them one of the few non-mammal species known to exhibit this ability. They also exhibit tool use, with crows, rooks, and blue jays observed using tools in both wild and experimental settings. Additionally, corvids have brain-to-body mass ratios comparable to non-human great apes, indicating a high level of cognitive capacity. 4 5 Corvids display various other indicators of intelligence, including empathy, emotional contagion, interspecific communication, cultural behavior, foresight, and spatial awareness. These behaviors suggest complex cognitive abilities and social interactions among corvid species. 6 7 8 9 10 Tool-use involves utilizing physical objects to accomplish tasks, while tool-making involves altering or creating tools to achieve specific goals. While tool-use is observed in various animal species, including corvids, tool-making is less common and has been documented primarily in some primates and the New Caledonian Crow in the wild. Tool Use in the Corvid Family (Carrion Crow, Rook, Blue Jay, New Caledonian Crow) Different species of corvids exhibit remarkable tool-use abilities. For example, carrion crows have been observed using passing cars to crack nuts, rooks use stones to raise the water level to reach food, blue jays use paper as a rake to retrieve food pellets, and New Caledonian crows craft hooks from twigs to extract insect larvae from tree holes. 11 12 13 14 15 16 While some corvids demonstrate tool-use behavior, not all species engage in this activity in the wild. Habitat characteristics, such as the presence of competitors or predators, may influence the likelihood of tool-use behavior in corvids. 17 Parrots, with approximately 398 species, are characterized by their strong, curved bills, upright stance, strong legs, and vivid colors. They are found in tropical and subtropical regions worldwide and have diverse diets consisting of seeds, nuts, fruit, buds, and other plant material. 18 Parrots have not passed the mirror test for self-recognition, but some species, such as Goffin's cockatoos and Greater Vasa parrots, have demonstrated tool-making and tool-use abilities in experimental settings. Their brain-to-body mass ratio is comparable to non-human great apes, suggesting a high level of cognitive capacity. 19 Parrots exhibit delayed gratification, sound imitation, speech, cooperation, and social learning, indicating complex cognitive abilities and social behaviors similar to those observed in primates. 20 21 22 23 24 Despite evolving in separate parts of the world and having different evolutionary histories, both birds (corvids and parrots) and apes show similar features of intelligence. This convergence suggests that intelligence may have evolved independently in different lineages to solve similar cognitive challenges in their respective environments. 25 The Torresian Crow and New Caledonian Crow are two species of corvids that have undergone speciation through allopatric processes. The Torresian Crow has evolved to thrive in urban environments, while the New Caledonian Crow has developed specialized tool-use behaviors to access food resources unique to its island habitat. These differences highlight the role of geographic isolation and ecological niches in driving speciation among corvid species. 26 27 28 29 30 Objective: Corvids Corvids are a diverse group of birds belonging to the family Corvidae, including species like crows, ravens, rooks, and jays. This objective focuses on understanding various aspects of corvids, including their intelligence, tool use, and evolutionary significance. Intelligence Measures: Corvids exhibit remarkable cognitive abilities, including problem-solving, social learning, and memory. This section explores different methods used to measure intelligence in corvids, such as the mirror test, tool use, and brain-to-body mass ratio. Corvids have shown self-awareness in mirror tests, indicating a high level of cognitive sophistication. Tool Use vs. Tool Making: Corvids are known for their adeptness at using tools to accomplish tasks, such as foraging for food. This section distinguishes between tool use, where birds utilize external objects to achieve goals, and tool making, where birds modify or create tools to suit specific needs. While many corvid species demonstrate tool use, tool making is less common and has been observed primarily in certain species like the New Caledonian Crow. Objective: Parrots Parrots are another group of highly intelligent birds known for their cognitive abilities and complex social behaviors. This objective aims to explore indicators of intelligence 31 in parrots and their evolutionary significance. Indicators of Intelligence: Parrots exhibit various behaviors indicative of high intelligence, including problem-solving, tool use, social learning, and communication through vocalizations. This section delves into the diverse ways in which parrots demonstrate cognitive abilities, such as delayed gratification, speech imitation, cooperation, and tool use. Objective: Evolutionary Benefits of Intelligence This objective investigates the evolutionary advantages of intelligence in birds, focusing on corvids and parrots. Intelligence allows birds to adapt to diverse ecological niches, solve complex problems, and navigate social interactions effectively. By exploring the evolutionary benefits of intelligence, we gain insight into the selective pressures that drive cognitive evolution in avian species. Objective: Torresian Crow vs. New Caledonia Crow This objective compares two species of corvids, the Torresian Crow and the New Caledonian Crow, to understand how they have adapted to different environments and ecological niches. The Torresian Crow thrives in urban environments and has developed behaviors to exploit human-made resources, while the New Caledonian Crow exhibits remarkable tool-making abilities to access food sources unique to its island habitat. By examining these species' differences, we can gain insights into the mechanisms of speciation and ecological adaptation in corvids. 31