Roughly a quarter of cats run around and kill things for no reason other than the thrill of the hunt 9 out of 10 of their kills. I'd call that destructive behavior.
Many nervous and stressed out mammals will eat their young the first time they produce.
Deer are normally the first to the scene of a kill in a forest, and they'll eat the carcass until scared off or until they've had their fill.
It's like a 1 in 5 or 1 in 20 chance that a Preying Mantis female will eat a male that she copulates with.
Mantis shrimp go around attacking anything with in arms reach.
Tansmanian devils and wolverines, enough said there.
Humans aren't special, really. Humans are just like any other animal, just they spend more time with themselves and have spent millennia alienating everything else on the planet to the point that they barely recognize the similarities to their genetic cousins. The only thing that is different between humans and everything else on the planet is that one, humans are intelligent enough to come up with some fairly creative and sadistic methods of hurting other living creatures. The second thing that separates humans from other animals is that many feel remorse or are strongly empathetic towards the pain of others, thus attempting to create social structures to prevent pain.
Personally I hold animal life on a similar level to human life. Based on the utility that each brings to a particular circumstance thus gives weight to which life is worth more. For example: a seeing eye dog, or the dog of an elderly human that lives alone will always have their life prioritized over a human convict in my eyes. The dog provides a needed service to either currently productive or previously productive humans and thus provides utility to society. Human convict on the other hand has proven to be a detriment to society, and thus has a lower priority for preservation. A rather exaggerated example, but it paints a nice picture to illustrate the concept.