I didn't want to hijack mrlexma's thread about trophies, but wanted to know what y'all think about this:

http://www.nationalpost.com/ne...tory.html?id=1170074

Trophy hunt changing evolution, study finds
Hunted getting smaller to survive: online report

Matthew Coutts, National Post
Published: Tuesday, January 13, 2009

In their pursuit of impressive trophies to stuff and mount in hunting lodges and bigger fish to fillet and throw on the grill, humans have rapidly changed the direction of evolution and created a case of "unnatural selection" in which it is not the strongest, but often the smallest, that survive, according to a new study.

In a report released online yesterday by the Proceedings of the National Academy of Sciences, researchers compiled studies into the evolution of animals and found that those hunted by man, such as bighorn sheep, caribou, salmon and cod, are forced to evolve far more rapidly than animals left alone, or affected by humans in other ways.

Not only that, but species hunted as trophies have reduced in size by nearly 20%, as humans pick off the large and the healthy and leave smaller and often weaker members to repopulate the chain and pass on their genetic composition.

This role as a "super-predator" has changed the course of natural selection, making it more so a question of survival of the smallest.

"On average, most predators tend to target the young ones, these are the ones that can't defend themselves, or the old and decrepit .... We come in as a super-predator and target those that are the prime in the population," says co-author Dr. Tom Reimchen, a professor at the University of Victoria.

"The consequences of that, without question, are going to lead to a significant affect of the prey population. What happens when there are none of these big healthy adults around anymore and you have most of the breeders being younger or smaller?"

According to the study, which considered data from 29 species from 40 different environments in which they were the prey, those hunted by humans evolve 300% faster than animals that are not affected by humans.

They also evolve 50% faster than animals that are touched by humans in other ways, such as those affected by pollution or those dropped into a new environment and forced to adapt.

By hunting the largest and most impressive specimens, researchers contend, humans are leaving their smaller kind to reproduce which, ultimately, leads to an overall reduction in the species' size.

"We are changing the very essence of what is left in the population, and specifically, we are doing that very rapidly," said the study's lead author, Dr. Chris Darimont, who began the work while a biology PhD candidate at the University of Victoria and is now a postdoctoral researcher at the University of California at Santa Cruz.

As an example, he pointed to the decline in body mass and horn size of Albertan bighorn sheep, which after 30 years of trophy hunting saw a 20% decline in size.

Hunting has also pushed such animals to breed at smaller sizes and younger ages which, according to Dr. Darimont, generally produces fewer offspring and further reduces their ability to recover from over-hunting.

"If humans are targeting large adults, they are also targeting reproductive aged adults and that gives younger breeders an advantage, because they can have their babies before they get big enough for humans to want to kill them," he said.

He added the only way to curb such changes to the system is to more closely mimic natural predators, by taking fewer from a population and for forgoing our preference to hunt the largest.

mcoutts@nationalpost.com

I think this article supports the premise posed by some that in the case of Cape Buffalo and Lion, we need to stop shooting the young and the breeders and exercise a more selective targeting of the older, past prime animals.

I don't have the expertise to speak to the animals cited in the study, specifically, but I do believe there is an argument to be made, along with a subjective visual evaluation that can be conducted, in the case of the two African species referenced above. I have hunted both of these species on more than a few occasions and believe such evaluations can be made reasonably during the hunt.

What a load of crap.

Do these "researchers" suppose those older males that make good trophies got old without reproducing, thus contributing to the gene pool??

And were these supposed "younger males" that are supposedly breeding instead dropped in by aliens rather than bred by those very males that were taken as trophies, and thus carrying the exact same genetic potential??

Don't get me started...

The auther totally forgets to take into account those of us who shoot young animals not for trophies but for meat.

There's not enough data supplied to know for certain, but this "study" strikes me as most probably a case where somebody had a predispostion and, then, looked for data to support his a priori conclusion -- while ignoring any data that might argue against his anti-hunting agenda.

Clearly, shooting of mature male animals after they have passed their breeding prime could not logically impact the gene pool in this way since the contribution of these animals to the pool would have already occured.

I'm betting that it's BS.

quote:

As an example, he pointed to the decline in body mass and horn size of Albertan bighorn sheep, which after 30 years of trophy hunting saw a 20% decline in size.

Hunting has also pushed such animals to breed at smaller sizes and younger ages which, according to Dr. Darimont, generally produces fewer offspring and further reduces their ability to recover from over-hunting.

My opinion is that this is a load of anti-hunting crap. Just for example, how many animals were in the pool and who weighed the Alberta Big Horns 30 years ago? How was the forage during the subject years? Horn size of harvested trophy animals may indeed be smaller as a result of more hunters, that is there are fewer really large animals to choose from but this doesn't mean the sheep are evolving smaller horns to avoid hunters.....in 30 years......horse manure.

Secondly, the male animal provides the sperm, the females who are not hunted normally are the ones who "control" the number and size of offspring. Assuming any validity to his arguments, there are well over one half of the breeding population, the females, who are not hunted and therefore would not be affected by "unnatural" selection.

If any of this is true they why are record animals being taken every year?

As soon as it said the word evolution the whole article become void.

I thought I would jump in here but it is pbvious that many of you have no idea hoe "Survival of the fitest" works and it would be a waste of time. So I won't!

465H&H