well I have a dog and even though cats and dogs behave very differently (dogs being on average more trusting thus dumber) I have noticed animals are particularly apt at avoiding dangerous substances. I know this is not always the case and sorry if someone lost any kind of pet over poisonous spillage of any kind but the fact remains that 9/10 an animal won't lick a chemical unless it was especially designed to be very inviting for the dog itself.

Several times in the mountains (I go climbing and hiking a lot hence the nick ) my dog has avoided streams and puddles even if thirsty. I can only infer that there was something wrong with the water which is entirely possible given that algae and especially chemicals used in cultivation and secondary agricultural activities are prone to be dispersed in the environment.

This is my two cents on how dumb dogs really are. We should give them more credit IMHO.

cheers