You've seen the videos yourself - dogs often need no external prompting for them to try to grab a woman's hips in an attempt to breed her.
Dogs have been selectively bred for so long by humans that they can now understand our facial expressions and also subconsciously mimic them to an extent (concerned eyebrows, "smiles", etc.). Other animals, such as horses, really aren't attracted to humans females. They can learn to be through positive reinforcement such as leading the horse to a stall with a woman where he then gets masturbated, but it doesn't seem to be as obviously an organic thing. I can't speak to boars on this point as I don't know.
Dogs, on the other hand, will often go up to a woman's vagina completely unsolicited to get a smell or a taste of a woman's pussy. While men subconsciously can tell when a woman is ovulating and tend to respond more sexually aggressively to the women, due to dogs' incredibly sensitive noses, a woman ovulating has a far more powerful impact on a dog than a man - launching the male dog into a breeding need.
In nature, dogs only tend to breed when a female dog is "in heat" and male dogs can smell her willingness from the pheromones she releases. Human females on the other hand are always "in heat", even when not ovulating, and are constantly sending out pheromones that signify "sex", which dogs cannot help but be attracted to.
This is all a hyper simplification, but it's a good rule of thumb. If a male dog's not neutered, and he sees a wet willing cunt of a human female in front of him, He Will Be Interested.
Join the debate, discover the science behind, and learn the signs of your dog's potential capabilites. Can dogs smell human pheromones? Find out now.
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Ever wondered, "Why do dogs sniff your crotch?" While the invasive sniffing can be embarrassing, there's a reason for it.
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