Final answer:
The statement that call systems rely almost totally on learning is not true; animal call systems are mostly innate and used in the presence of specific stimuli.
Step-by-step explanation:
The statement that is not true about call systems is: D. They rely almost totally on learning. Call systems in animals are mostly innate rather than learned. Animals like chimpanzees and gorillas use call systems that consist of a limited number of sounds, and these are used only in the presence of certain stimuli. For instance, chimpanzees produce a range of calls such as hoots and grunts, and gorillas use similar communication methods. These calls typically cannot be modified to refer to specific objects or concepts beyond their immediate context, unlike human language which is highly flexible and creative, allowing for an infinite number of combinations and expressions.
Research on primates and their communication methods, such as the studies on vervet monkeys, shows that while they may respond to specific alarm calls that indicate the presence of predators, their responses are not indicative of language in the human sense, as their calls are not open-ended or creative. Instead, their call systems are comprised of fixed responses to particular stimuli and are innate behaviors. Therefore, the reliance on learning is not a characteristic trait of animal call systems.