Some evolutionary psychologists believe that the latter is rooted in the universal fear of animals and an associated attempt to appease the beasts through emulation.

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Kids are less likely to fear wild animals, Willoughby says, and because of their small stature, they are more likely to be bitten in the face or neck, which means the virus can travel to the brain much more quickly.

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The next day the animals' fear of the tone had greatly diminished, indicating that the drug had prevented the old memory from being stored again.

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The animals have no fear of humans, so your children will swim with dolphins and turtles and play near seals.

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As a result, animals have little fear of humans.

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Conservationists also fear increased poaching, because the animals are easier to find as they bunch up around the few remaining water holes.

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Wildlife groups in Sri Lanka say they are withdrawing support to an elephant census as they fear it will be used to bring more animals into captivity.

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Dodman said that while it's fairly evident that animals experience primary emotions such as fear, what has been more hotly debated is whether they have secondary emotions like jealousy and guilt.

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Buck's work has also widened to include pheromones: chemicals released by animals that act on members of the same species to stimulate responses like fear and aggression.

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