It is particularly associated with a dependence upon sexual activity, our most basic animal instinct, hence the reduction in the sex-drive and a return to a childlike, innocent self-awareness during recuperative states.

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Hammersmith's Groves was given the sternest test of his unbeaten 10-fight career, climbing off the canvas in the third round and relying on animal instinct to stop his fellow unbeaten prospect in the sixth round.

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The water had been cold, her teeth had chattered, but her hands had not let go of the oar perhaps she had been a true coward, or perhaps she had been overcome by animal instinct, hanging on to life blindly.

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"When he is conducting, there is this animal instinct which comes out of him and you don't see it in rehearsal, you see it when he is performing and the look on his face, " says Matt Gibson who plays the double bass for the LSO.

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She is put through a mini-bullfight complete with a matador, picadores (lancers on horseback) and banderilleros (who thrust barbed darts into the animal) to test her speed, strength and instinct to charge.

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