Brief, often subtle behavioural signals that precede more obvious behaviours.

A horse pinning their ears for a half-second before swishing their tail, a dog freezing for a moment before growling, a cat tightening their facial muscles before lashing out, a parrot fluffing slightly before a beak strike, are all microexpressions. The signals are typically very brief (fractions of a second to a few seconds), often subtle, and frequently missed by handlers who are not specifically looking for them.

Microexpressions are part of the broader phenomenon of body language and are particularly important because they offer the earliest opportunities for handlers to read what an animal is about to do. A handler who reads microexpressions well can intervene in many situations before the animal escalates to more obvious behaviours that would have welfare or safety consequences.

The skill of reading microexpressions develops with practice and conscious attention. Most handlers, when given good footage of their animal and asked to look for specific signals, can identify microexpressions they had missed in real time. The skill is to bring the same level of attention to live interactions, which requires both training and ongoing practice.

Microexpression reading is particularly important in welfare-positive training and handling. Modern positive-reinforcement training relies on reading the animal’s state continuously and adjusting the work to keep the animal under threshold and engaged. Microexpressions provide the earliest signals that the animal is starting to disengage, become uncomfortable, or move toward reactivity. Catching these signals early allows the trainer to adjust the session before the animal crosses into states where learning becomes impaired.

The concept overlaps with what some training traditions call “pre-signals”, “warning signs”, or “early indicators”. Different frameworks use different terminology, but the underlying observation is the same: animals offer information about their state before they offer obvious behaviours, and skilled handlers can read and respond to that information.