I'm going to give it to the shrews. A tiny little shrew, with three bites, can paralyze the leg of a 200 pound adult male human. That's potent. Considering they eat mice, voles, insects and moles, that's plenty enough for their needs.

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In your rush to call everyone "entrenched" or closed-minded or "limited" you fail to note that the "limit" here has a very natural boundary: that point at which the evidence stops. - JayUtah

Science fiction was never meant to be an educational tool. - Editor Amazing Tales