Devolution: African elephants survive by shedding their tusks
Evolution Genetics Intelligent Design
Posted on November 17, 2018 Author NewsComments(3)
A classic in devolution, actually. In Mozambique, it is estimated that 90% of the elephants have been slaughtered for ivory to finance a civil war that ended in 1992. But tuskless elephants seem more likely to survive:
Hunting gave elephants that didn't grow tusks a biological advantage in Gorongosa. Recent figures suggest that about a third of younger females—the generation born after the war ended in 1992—never developed tusks. Normally, tusklessness would occur only in about 2 to 4 percent of female African elephants.
Decades ago, some 4,000 elephants lived in Gorongosa, says Joyce Poole—an elephant behavior expert and National Geographic Explorer who studies the park's pachyderms. But those numbers dwindled to triple digits following the civil war. New, as yet unpublished, research she's compiled indicates that of the 200 known adult females, 51 percent of those that survived the war—animals 25 years or older—are tuskless. And 32 percent of the female elephants born since the war are tuskless. Dina Fine Maron, "Under poaching pressure, elephants are evolving to lose their tusks" at National Geographic
The trait (no tusks or else have tiny tusks) was there all along but became an asset when the main foe was attracted to, rather than deterred by, tusks. The double whammy may have meant even more rapid change.
In other news, this has certainly been "Devolution Week" at Uncommon Descent, if we go by some of the other stories, linked below. Everything seems to be devolving except our numbers of readers, which spiked recently. Yay, readers! Keep coming back!
Seriously, devolution is a bit like extinction; it's under-considered as a source of evolution, probably because it doesn't fit the expected and sought-after pattern. One problem is, we then don't get a clear picture of what is happening. News
What if simplification is a common way life forms evolve? Would we want to know that or not?
Follow UD News at Twitter!
See also: John Sanford on claims about brand new nylonase genes
John Sanford gives lecture at NIH on mutations and human health
A peek at Mike Behe's new book Darwin Devolves We're told that the basic thesis is, The First Rule of Adaptive Evolution: Break or blunt any functional gene whose loss would increase the number of offspring.
Huge study shows yeasts evolve by reducing their complexity If losing complex traits is a reliable and successful form of evolution, how did successful life forms acquire great complexity in the past, when there was less time to evolve?
Devolution: Getting back to the simple life (an overview)
Tagged devolution, elephants
Researchers: Ribosome translational system dates back to earliest Earth
The term "mechanome" is catching on, but slowly
3 Replies to "Devolution: African elephants survive by shedding their tusks"
Isn't this evolution/devolution dichotomy a somewhat outdated view? Evolution is not seen as progressive, improving, moving forward, increasingly complex with devolution implying the opposite, regressive, deteriorating, going backwards, becoming simpler.
Evolution, in the adaptive sense, is simply change in response to immediate environmental pressures. It makes use of whatever 'tools' happen to be available in the genome at that time. If a gene is found to assist an organism in meeting an environmental challenge, even if there is a consequent deterioration in another function, if it enables the organism to survive and reproduce in that environment then any metabolic cost is acceptable. It's not about getting better or getting worse, it's not about increasing or decreasing whatever you mean by 'information', it's simply about adapting and surviving if at all possible.
AaronS1978 says:
I don't think anybody would disagree with you I most certainly don't.
The issue comes in when involving Darwinian evolution which is an end-all be-all explanation for anything, capable of creating information instead of staying to the toolbox that it already has. That is were things become a little sticky.
The above would be no different than me eliminating a particular hair color from population, for example there's a mixture population of redheads and blondes and I decided to start eliminating blondes because they just have more fun. I know I'm a blond. But soon after there would only be redheads left which don't have more fun. HA!
But seriously I wish more people had your take on it most, with the people I encounter, evolution is the end-all be-all capable of explaining everything including the flying spaghetti monster if you give it enough time. But that's where I start having contentions with in.
ET says:
Seversky:
Evolution, in the adaptive sense, is simply change in response to immediate environmental pressures.
That is not the evolution of Darwin, Mayr, Dawkins and Coyne. They all say that evolution proceeds by happenstance changes that are then culled by nature. If the changes happen in response to the environment then it is telic evolution.
It's not about getting better or getting worse, it's not about increasing or decreasing whatever you mean by 'information', it's simply about adapting and surviving if at all possible.
1- Crick defined information with respect to biology. Don't blame us for your willful ignorance.
2- You have just proven that your position has nothing to explain the diversity of life.