Hm. I'd still like to read the original, if/when you get a chance.
However, I'm inclined to think this "increasingly aberrant" behaviour is caused largely by the overpopulation of H. sapiens on this mud ball, and the constant encroachment of H. sapiens on the territory of wildlife. I still think it would be instructive to plot "aberrant activity" against "human population trends" and see what comes up.
It's like when AIDS came about in the 1980's - we were starting to get overpopulated then. It was Nature's way of "cleaning house" - come up with a fatal disease that is transmitted by the act of indiscriminate procreation in an attempt to reduce the birth rate. AIDS didn't work - so now it's "when animals attack." I call it Nature trying to balance the book.
I find some small truth in Agent Smith's monologue in the first Matrix movie, wherein we were compared to virii. Of all the species on Earth, we're the only ones who don't achieve a "balance" with available resources (among the higher life forms - chordata would be the taxonomic cut-off point, I think.) Virii & bacteria exhibit similar behaviour - mainly due to a lack of intelligence. We're too smart for our own good - "we're so smart, we're dumb."
The solution is quite simple, but no-one will come out and say it. We need to achieve negative population growth, as a planet, for about fifty years. Get global population back down under four billion, and we should achieve balance.
I recall a logistical exercise a group of us did when I was in high school. "Assume that the Earth's resources are finite. (They are.) What would be the population of H. sapiens that would be in the greatest balance with available resources, assuming no alternate territory (undersea habitats, space colonisation, terraformed planets) presents itself? Prove your answer."
I wish I could find that paper we wrote, but a detailed analysis of resources at the time showed that we were already overcrowded at the time in a logistical sense (this was ca. 1988.) "Balance population" was determined to be 3.75-4.25 billion people - and we were already upwards of 4.5 billion.
This was taking into account not just logistical factors (food supply, water, housing, &c.) but also psychological factors - the need for "space" among adult humans. Overcrowding need not be merely reflected in resource shortages.
How much farther will we go before people attacking people for no good reason becomes commonplace? Who is to say that serial killers, for the last 20-25 years, haven't been yet another attempt by Nature to "balance the books?"
Damn global warming - if we keep breeding like virii, the race won't be around long enough to deal with global warming anyhow. Meanwhile, we should probably all acquire a taste for Soylent Green...