Naming, describing, and quantifying behaviour

First of all, here’s a robin for you:

Goal

To give you a feel for some of the decisions involved in naming behaviours, describing them to other people, and converting them into the numbers you’ll need to test hypotheses quantitatively.

Procedure

Watch an animal – any animal – for at least an hour. Make a list of the behaviours you see, giving each behaviour a name and a description, and offering at least one possible way to quantify that behaviour.

Points to remember

Categorizing behaviour: Most behaviours (e.g., grooming) consist of component behaviours (e.g., rubbing head), so in deciding which behaviours to name you’ll have to decide what’s too much detail and what’s not enough. Categories should be consistent (not overlap) and exhaustive (represent everything the animal’s likely to do). They can be hierarchical; in fact, they often are (i.e., there can be categories within categories – e.g., biting and hitting might be subcategories of fighting).

Naming behaviour: Names based on structure (e.g., “lip corner lift”) can more ponderous and less vivid than those based on function (e.g., “smile”), but the latter risk prejudicing your observations if you go too far (e.g., “happy face”). As a general guideline, names should be structural, but don’t carry this guideline too far, either (e.g., “walking” is a better name than “alternate leg movement with anteriorad body propulsion”).

Defining behaviour: Describe each behaviour in sufficient detail so that, if another observer saw what you did, they’d report the same behaviours as you. Note there’s a distinction between defining and describing behaviour. The definition of a behaviour consists of the features that distinguish that behaviour from others. The description of a behaviour consists of features that convey what the behaviour looks like (or sounds like, or smells like). Both are useful, but we’ll see in future exercises how the definition is critical if different people are to measure behaviours in the same way.

Quantifying behaviour: Your main options are latency, rate, duration, and intensity. Your first criterion for which to use is whether the behaviour is an event or a state. A good measure is also reliable (i.e., can be measured consistently) and valid (i.e., measures what you really want to measure), although the latter criterion is hard to judge until you know what question you’re trying to answer.

Homework and write-up

After you’ve tried the above exercise a couple times, expand and improve on it by writing up an ethogram (i.e., an exhaustive list of behaviours, with their definitions – and descriptions where useful) of an animal’s behaviour. For each behaviour, include what you consider to be a good measure of that behaviour.