I've come across multiple bioacoustics studies that attempt to describe the function of a particular call made by animals - i.e. by ascribing meaning to stereotyped calls that are given in particular contexts.

Some examples include;

• echolocation clicks used for finding food in bats and odontocetes, or;
• "loud/long" calls of many primates, such as gibbons or howler monkeys, that are associated with pair-bonding or territorial defence, or;
• sexual advertisement calls of frogs, or;
• contact calls given by ungulates for social cohesion in groups.

In a lot of other instances there seems to be no way of knowing. For example, it seems like most aquatic species have unknown functions for their calls, or that there is extreme difficulty in understanding those functions.

I have three questions:

1. What are some of the more straightforward ways to frame hypotheses that test the functions of these calls?

2. How can we be sure that what we are contextualising is actually related to the physical properties of those calls?

3. Are there any decision trees or resources for determining the functions of calls? For instance, if a type of call (e.g. echolocation) is given in a specific context will that call always be considered "functionally specific", regardless of whether the animals is a human or a bat or a dolphin?

I've come across multiple bioacoustics studies that attempt to describe the function of a particular call made by animals - i.e. by ascribing meaning to stereotyped calls that are given in particular contexts.

Some examples include;

• echolocation clicks used for finding food in bats and odontocetes, or;
• "loud/long" calls of many primates, such as gibbons or howler monkeys, that are associated with pair-bonding or territorial defence, or;
• sexual advertisement calls of frogs, or;
• contact calls given by ungulates for social cohesion in groups.

In a lot of other instances there seems to be no way of knowing. For example, it seems like most aquatic species have unknown functions for their calls, or that there is extreme difficulty in understanding those functions.

I have three questions:

1. What are some of the more straightforward ways to frame hypotheses that test the functions of these calls?

2. How can we be sure that what we are contextualising is actually related to the physical properties of those calls?

3. Are there any decision trees or resources for determining the functions of calls? For instance, if a type of call (e.g. echolocation) is given in a specific context will that call always be considered "functionally specific", regardless of whether the animal is a human or a bat or a dolphin?