At moments his face took on a touch of worry, the kind that a rat would show.

The rats soon showed fear when they heard the noise without the shock.

The once neutral stimulus is given again to see if the rat would show the responses of fear.

Again, the law had crooks on the run, but once more, rats showed purpose in their flight.

Female rats show some interesting characteristics in regards to sexual behaviour.

The rats had not shown themselves again, but I'd begun to feel them watching me from shadowed hiding places.

Rats that were given meat instead of the placenta showed no increase in the pain threshold.

The black rat shows preference for snails with larger shells (greater than 10mm).

When other options and behavioural opportunities were put in place, the rats soon showed far more complex behaviors.

Shiversomely, the rats showed a human sagacity in many of their actions.