The error in this is the assumption that the weaker, smaller animals are "less fit." From a purely natural selection point of view, one would not that the selection landscape has changed, and that smaller animals are now MORE fit under a fitness regime that includes effective predators that target large, big-antlered animals. The predictable result is selection for animals that are some combination of (1) more sneaky, (2) less visible, or (3) bearing smaller antlers.

I've long-suspected that selection for small males is occurring in southern Arizona. There's a lot of baloney about how small the "Coues" white-tailed deer is. That is true of the males. The females I have seen are often within the range expected for other parts of the country -- bearing in mind that around here they're not corn fed on amber waves of grain.

My explanation is that AZGFD issues too many permits, such that males very rarely live past 2-3 years of age. In the absence of robust, mature males, even a shy, diminutive, weak male (if he is cuatious and stealthy) has excellent access to females, and it is his genes that are passed along. Perhaps the ultimate result will be antlerless male deer. You can only shoot "antlered deer" in AZ.

Make no mistake there are PLENTY of does out here. I can't go rabbit hunting anywhere without pushing around at least one doe.

Mike, I just don't think that it's possible for hunting to have any impact on selection one way or the other and here are my admittedly non-scientific and purely anecdotal reasons.

One, although it seems counter-intuitive I actually believe that if anything hunting pressure tends to skew selection toward potentially larger bucks, not away from it, and the key word there is potential.
The vast majority of bucks harvested during most states' firearms seasons are year-and-a-half old bucks. Simply put, lots of young, stupid deer tend to get shot first. And despite the reams of sometimes spurious stories written on how big bucks turn so stupid during the rut, my own experience on public land has taught me that rut or no, a big mature whitetail will respond to hunting pressure no matter how badly he wants to get some, and that hunting pressure drives a lot of rut activity nocturnal.
A big whitetail with a few seasons under his belt knows those smelly, loud boomstick things aren't around at night, so he's free to whip smaller bucks and breed with impunity.
And that segues into my next point, which is the seeming absence of large dominant bucks doesn't necessarily mean an absence of large dominant buck genes. Every big buck was once a small, shy basket-racked buck. Just because those small bucks are small right now doesn't mean they don't possess the genes to grow big.

I will concede that hunting pressure can perhaps affect that potential by keeping a large numbers of potentially large bucks small by shooting them before they have a chance to get large, but then that just gives the few bucks that do manage to live an even better chance of breeding, which then sort of perpetuates the whole cycle over again.

So whatever it is that might be affecting the physical characterisitics of a given population I don't think it's being driven by genetics nearly as much as it's being driven by management practices.

And that's why I think the story is utterly bogus, and why I think the deer harvest age-class structures in states that actively promote higher doe harvest and quality management would bear that out. If you shoot more does and fewer bucks those bucks that survive will grow larger.
So if there was a genetic predisposition toward smaller deer wouldn't it manifest itself despite such management practices?

I guess it all boils down to I believe those small, shy, weaker animals the article references are more likely to be shot than large, dominant animals, not less likely because I simply don't have that much faith in my species' ability to consistently outwit an educated game animal.

How's that for a defeatist attitude?

Chad we mostly agree. I think the results that I expect for Arizona are primarily a consequence of game management strategies. But I can also see how natural selection would work to select for smaller, wiley bucks.

"So if there was a genetic predisposition toward smaller deer wouldn't it manifest itself despite such management practices?"

Not entirely. The game management practices impose a kind of skewed fitness regime. After all, it's the hunting rules that, if obeyed limit what we can shoot. We can see sexual dimporphism in many species, and this is often manifested as bigger males and smaller females. This observation indicates that given enough time, dimporhism can be sex-linked. But I think that your point that the 1.5-3 year olds tend to get shot is also very important. The wiley bucks, big or small, figure things out and avoid getting shot.

Maybe then, the characteristic that we're selecting for is "smarter deer." If they ever get themselves organized, things could get interesting.

Smarter deer or just more paranoid?

I think some deer are just a bit more skittish by nature and basically afraid of their own shadows. These deer tend to be more nocturnal and thus survive longer that those who don't.

FWIW, I don't think it's the boom stick that keeps deer freaked out as much as the intrustion of hunters into the woods in the dark. It doesn't take a spooky, paranoid animal long to figure out somethings up.

Jim

I covered this over on my blog, (The Hog Blog) when the article came out, and I'm actually glad to see it getting a fair slamming around the blogosphere.

The researchers themselves, at the end of Ms Huang's article, cleary say that the evidence to support this "theory" is far from conclusive.

What kills me is that the whole thing points at hunting, but uses examples that are primarily drawn from isolated populations of animals that are generally (exception of Quebec bighorns) poached. Huang also excludes any mention of other likely causes for diminution of some species, that may include changes in climate and/or habitat.

The general theory of Darwinian Selection is interesting and plausible, and I can't argue with the fact that we should pay attention. But the article as published by Newsweek is misleading at best, and intentionally propagandistic at worst.

The argument itself, that hunters are hurting the species, is ancient in the anti vs pro hunting debate, and it's been roundly rejected as having any grounds in fact... anecdotal or scientific. Huang's article strikes me as little more than an attempt to revive the argument in order to sway a few more non-hunters against the sport.

my question is this. Are the genes from a year and a half year old deer different when he turns 4 or five year olds? do genes change with age? Does a deer that breeds at 1 1/2 produce an interfior deer than if it would breed at 4 1/2? I don't think so, that is why QDM works, cuz those deer are just waiting to grow large, no matter how many years of yearling harvest takes place.

Thats an interesting post, i wonder what would happen if only the "weak and scrawny" humans survived. Food for thought. Keep up the good work with your blog, it's excellent!