African Elephants Are Being Born Without Tusks Due To Poaching, Researchers Say

[Fweethawt]

http://www.independent.co.uk/news/elephants-africa-tusks-ivory-poaching-born-without-a7440706.html

 

The species could become extinct in some areas, with those elephants that do survive evolving to be almost completely tuskless

[rjn]

I wonder if the stress those animals endure because of poaching also affects the stunted growth of the tusks? So it's not only natural selection? Just a thought. 

[Fweethawt]

There's a more proper term for this type of "selection" that escapes me at the moment. It's not called natural selection though.

[LogicalFallacy]

Isn't the term 'environmental pressures'? The basic idea that external pressure from the environment (In this case being hunted) leads to genetic traits that allow survival (lack of tusks, therefore not hunted) and therefore for those with the genetic trait to survive and reproduce?

[duderonomy]

This is pretty interesting, but how could genetic changes like that happen so fast? 

[LogicalFallacy]

It's possible that evolution can speed up given the right pressures. So depending on factors occasionally evolution may 'boost'. I'll call this hypothesis the "evolutionary boost hypothesis". Now we just need to predict and observe whether this is the case.

[duderonomy]

Well either way, these elephants may forgive us for this, but they will never forget.

[sdelsolray]

This is pretty interesting, but how could genetic changes like that happen so fast? 

 

 

I wouldn't be surprised if only one to a few genes govern the formation of elephant tusks.  A mutation in one of them in the gamete might be sufficient to cause them not to grow at all in the offspring.  Query next whether that mutation would be recessive or dominant in the next generation, i.e., would it require both parents to have the mutation or just one?

 

Humans have been hunting elephants for their ivory for centuries, killing them to harvest the ivory instead of sedating them and sawing off the tusks.  That environmental pressure favors individuals without tusks.  It is only in recent decades that the elephant population has gone into crisis.  Leaving sexual selection pressures aside for the moment, the tuskless elephants are better adapted to reproduce in the current environment, according to standard biological evolutionary theory.  Sexual selection pressure may, or may not, be present regarding tuskless elephants.  I don't know one way or the other.  If it is present, prospective mates may reject a tuskless potential partner and prefer one with tusks.  

 

In any event, there have always been tuskless elephants (about 5% or so).  So whatever mutation(s) can cause this are already in the gene pool.  In evolutionary parlance, the change in allele frequency in the gene pool is resulting in an increased phenotype expression of no tusks in the population.

 

Once a beneficial mutation is present in the gene pool, it can spread to the most of the population within several generations.  This is how the change is happening "so fast".

[Fweethawt]

Well either way, these elephants may forgive us for this, but they will never forget.

Nice... But I think I herd that one before.

[duderonomy]

 

...Once a beneficial mutation is present in the gene pool, it can spread to the most of the population within several generations.  This is how the change is happening "so fast".

 

 

Thanks for the info. I guess I wasn't considering how long overall the poaching has been going on.

[duderonomy]

 

Well either way, these elephants may forgive us for this, but they will never forget.

Nice... But I think I herd that one before.

 

 

Ha-ha! We're talking about African elephants, and you slipped in a frican pun!  Clever.

[rjn]

There's a more proper term for this type of "selection" that escapes me at the moment. It's not called natural selection though.

 

Reminds me a bit of Lamarckism, but that was discredited by Darwinists 150 years ago or so. 

[LifeCycle]

Sad isn't it? But amazing at the same time. They know they're being hunted for their tusks.... One of the biggest giant bull Elephants in Botswanna hides his tusks in the brush when humans are around. He knows those things are what the poachers are after. It's fucking sad. They're amazing creatures. Goddamn humans suck sometimes.

[Fweethawt]

 

There's a more proper term for this type of "selection" that escapes me at the moment. It's not called natural selection though.

Reminds me a bit of Lamarckism, but that was discredited by Darwinists 150 years ago or so.

I THINK the term is, artificial selection. I've only heard the term in one other instance in Cosmos when Neil Degrasse Tyson was explaining the domestication of (some) wolves into "dogs".

 

I think it's a change that takes place due to UNNATURAL activities-- namely human ones.

[sdelsolray]

 

 

There's a more proper term for this type of "selection" that escapes me at the moment. It's not called natural selection though.

Reminds me a bit of Lamarckism, but that was discredited by Darwinists 150 years ago or so.

I THINK the term is, artificial selection. I've only heard the term in one other instance in Cosmos when Neil Degrasse Tyson was explaining the domestication of (some) wolves into "dogs".

 

I think it's a change that takes place due to UNNATURAL activities-- namely human ones.

 

 

 

 

Human activity is part of the natural environment for other species and any human activity which affects another species' population should be considered part of natural selection.

 

Artificial selection is different.  Humans choose and direct reproduction within a population seeking phenotypical changes within the species, such as has been accomplished with corn, wheat, tomatoes, dogs, etc.  In essence, the environmental pressure, which drives the natural selection process, is absent with artificial selection.

 

The chemical and genetic processes are the same in natural or artificial selection.  

[Fweethawt]

I didn't think that mass killing of an entire species for profit was considered to be natural which is why I was thinking along the above comments.

[sdelsolray]

I didn't think that mass killing of an entire species for profit was considered to be natural which is why I was thinking along the above comments.

 

 

For purposes of evolutionary theory it is.