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Female African elephants are evolving without tusks due to ivory poaching

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Re: Female African elephants are evolving without tusks due to ivory poaching

#181

Post by allturtles »

klodolph wrote: post #155
rsj_hn wrote: post #140

Earlier quoted context omitted.

Why not? I often see people draw this distinction between humanity and nature, as if we weren't part of nature, and there is something deeply misanthropic about it. Of course we are part of nature. We may be screwing over the habitat of other animals -- like rabbits in Australia or pythons in the everglades -- but we are certainly part of nature and this is a textbook case of natural selection at work.

That is exactly what the distinction "natural / artificial" means... it's not some kind of judgment. In this sense of the word, artificial just means "by humans".

"artificial selection" means people selectively breeding for traits they find desirable [0] [1]. e.g. "I want a short-legged dog, so I'm going to keep breeding the shortest-legged dog from each generation together." That's not what's happening here. The poachers aren't trying to create tuskless elephants.

You can't peel off the "natural" in "natural selection" in this case and say "because this is done by humans, it's artificial selection," when artificial selection already has a distinct meaning.

[0]: https://en.wikipedia.org/wiki/Selective_breeding [1]: https://www.nationalgeographic.org/encyclopedia/artificial-s...

Re: Female African elephants are evolving without tusks due to ivory poaching

#182

Post by mfer »

jawarner wrote: post #171
mfer wrote: post #169

Earlier quoted context omitted.

Is this actually evolution? I ask because it’s not a change in the genetic structure of elephants. It’s an existing trait becoming more wide spread.

Yes, this is evolution, and that's generally how evolution works. There is some diversity in a population, and natural selection promotes some traits over others.

Looking at definitions in dictionaries I don’t see this. What am I missing? Honest question.

There are no new species and there is no change to genetic code

Re: Female African elephants are evolving without tusks due to ivory poaching

#183

Post by theduder99 »

BitwiseFool wrote: post #62
mysterydip wrote: post #53

What if unicorns at one point existed, but were hunted for the superstitious power of their horns, leaving only the hornless to reproduce and eventually eliminate the gene? How would we know?

There are plenty of horses and horse-ancestors in the fossil record. We would at least expect to see some horn material preserved. Failing that, there would be evidence on the skull itself due to how the attachment of the horn would leave evidence of its existence on the bone of the skull. You would probably also expect to see some horns in archaeological caches. I know they sometimes find narwhal tusks in burial sit…

As a kid being taught evolution, I made the natural assumption that many transitional forms of animals would be found in the fossil record in order to support the theory. However that is not the case(to put it mildly). When confronted with this fact, "scientists" created a new theory called punctuated equilibrium. what a house of cards..

Re: Female African elephants are evolving without tusks due to ivory poaching

#184

Post by ninkendo »

engineer_22 wrote: post #165
TehCorwiz wrote: post #151

Earlier quoted context omitted.

Evolution IS selective breeding. The members of a species most fit for their environment are successful in procreation. The female elephants without tusks are surviving at higher rates which is resulting in more offspring with no tusks. This causes a shift in the population where a trait previously with no or little benefit becomes advantageous and the shift in genetic makeup of the whole population evolves.

But we don't commonly run around saying Arabians and Morgans are different because of evolution. Neither do we say that chihuahua's and labradors have evolved into their present form. In my humble opinion "evolution" refers to speciation, which takes very many generations.

We already have a term for speciation though. Evolution is more broad.

Re: Female African elephants are evolving without tusks due to ivory poaching

#185

Post by drtz »

jsnell wrote: post #12

In case anyone is wondering about the size of the effect, https://www.nationalgeographic.com/animals/article/wildlife-... has the numbers. Before the war, 2-4% of female elephants were tuskless. Now 32% of newly born ones are. So it's a significant change, but it's not like this property was coming out of nowhere. It started off about as common as humans having green eyes.

> It started off about as common as humans having green eyes.

Elephant poaching has been around since long before the Mozambique civil war. The number of tuskless elephants may have been at 2-4% prior to the war, but that doesn't mean that lower levels of poaching didn't push it up to that level from some much lower naturally-occurring level.

2-4% seems like a _very high_ rate for a trait that could negatively impact a female's chance of survival AND kills 100% of her male offspring.

Re: Female African elephants are evolving without tusks due to ivory poaching

#186

Post by MAGZine »

mfer wrote: post #182
jawarner wrote: post #171

Earlier quoted context omitted.

Yes, this is evolution, and that's generally how evolution works. There is some diversity in a population, and natural selection promotes some traits over others.

Looking at definitions in dictionaries I don’t see this. What am I missing? Honest question. There are no new species and there is no change to genetic code

genetics is random. Each new generation combines genetic material from their ancestors, plus some new random mutations.

natural selection, i.e. the environment they're born in, is what picks winners and losers among those inherited characteristics and mutations.

Almost all individual mutations on a genetic level are benign. It's the combination of (selection of specific trait + compounding change) that is what we know as evolution.

In this case, the "change to the genetic code" produces elephants without tusks. That happened by change. But now, the elephants without tusks are the ones who get to live, because they're not poached. That specific mutation allows them to live/thrive. In the same way better hearing might allow a bird to evade its predators.

"no change to genetic code" ignores the fact that there are elephants wandering around who don't have (and will never have) tusks. (also: evolution is quite slow. this by any right is a huge, "forced" evolution. not in that we forced a change in the genetic code through editing it, but we are changing the course of genetics in a species through our collective behaviour).

Re: Female African elephants are evolving without tusks due to ivory poaching

#187

Post by meej »

mfer wrote: post #182
jawarner wrote: post #171

Earlier quoted context omitted.

Yes, this is evolution, and that's generally how evolution works. There is some diversity in a population, and natural selection promotes some traits over others.

Looking at definitions in dictionaries I don’t see this. What am I missing? Honest question. There are no new species and there is no change to genetic code

Evolution doesn't necessarily imply "new species" (species is actually a pretty vague term) and dictionary definitions are limited.

Try this resource instead: https://evolution.berkeley.edu/evolibrary/article/evo_01

Re: Female African elephants are evolving without tusks due to ivory poaching

#189

Post by hcarvalhoalves »

mulmen wrote: post #148

Is this actually evolution or just selective breeding? By killing elephants with tusks the poachers are favoring elephants with the no-tusk gene. This isn't a lot different than killing a dog that bites sheep, which is how we bred herding dogs. Or a wolf that eats your baby, which is how we domesticated dogs. This trait already existed so it certainly wasn't "engineered due to mass poaching for ivory" as claimed.

Humans exerting selective pressure are also part of nature, so I guess this is evolution.

"Selective breeding" is a term used when humans engineer species on purpose. In this case it's the opposite actually, elephants are adapting to survive poachers. Selective breeding would be if poachers started raising tusked elephants in farms.

Re: Female African elephants are evolving without tusks due to ivory poaching

#190

Post by aziaziazi »

PradeetPatel wrote: post #156

At the risk of being downvoted to oblivion, is there such thing as ethicially sourced ivory? If not, I imagine the only reasonable thing to do would be to educate and raise awareness on the catastrophic impact poaching has on the elephant species as a whole.

It depends on your owns consideration of what is ethic : some animist may not consider ethic to take part off a dead corpse. Others may draw the line between wild and bred animals. You may also consider that it is ethic to kill a living being if you do it in an « honorable » way (use your own definition of honorable) , as in coridas or hunting.
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