[HN Gopher] Female African elephants are evolving without tusks ...
___________________________________________________________________
Female African elephants are evolving without tusks due to ivory
poaching
Author : amrrs
Score : 283 points
Date : 2021-10-27 17:34 UTC (5 hours ago)
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(TXT) w3m dump (theswaddle.com)
| AtNightWeCode wrote:
| Evolution is in general very slow when it comes to animals. I
| have my doubts if poaching is the true cause or if there is some
| environmental reason.
| ithinkso wrote:
| I think that in this case it might just be a case of 'selective
| breeding' rather than 'evolution' sensu stricto.
|
| Those with large tusks are shot dead and thus only tuskless
| remain. Not much different with breeding dogs for specific
| traits which is way faster process than evolution to adapt a
| species to the environment
| ceejayoz wrote:
| Evolution needn't be slow. We've evolved (via _un_ natural
| selection) chickens over just a few decades to have more and
| more white breast meat, to the point where they can't stand up
| on their own. We've rapidly evolved dog breeds to have
| characteristics we covet.
| nemo44x wrote:
| Because the ones with tusks are being removed from pool
| (killed) before they can reproduce. Therefore their genes are
| not replicated and that characteristic goes away.
|
| It's more selection than "evolution" but they work together.
| treeman79 wrote:
| This could be better defined as breeding for specific traits.
|
| Elephants without tusks are the ones "allowed" to breed.
| woodruffw wrote:
| The article is explicit that it's an environmental pressure
| selecting for a previously recessive trait, similarly to
| Peppered moths during the Industrial Revolution[1].
|
| [1]: https://en.wikipedia.org/wiki/Peppered_moth_evolution
| Jyaif wrote:
| If there was a deadly virus that killed human that do not have
| blue eyes, the entire human population would "evolve" to having
| blue eyes very quickly.
|
| This is exactly what happened with the tusk-less elephants.
| AtNightWeCode wrote:
| Some eye colors are dominant. We still have a lot of
| different eye colors.
| mrlatinos wrote:
| Evolution is slow when humans aren't a involved. Most poachers
| kill the elephants for the tusks. This is artificial selection,
| similar to dog breeding, which is different from natural
| selection.
| mypalmike wrote:
| Humans or no, environments can change quickly and
| drastically, causing certain genetic characteristics to
| quickly become favored for survival and reproduction.
| Evolution is all about generational adaptation to changing
| environments. When the environment changes quickly, evolution
| can happen quickly. Populations simply disappear if the
| necessary adaptations cannot occur quickly enough.
|
| https://www.sciencedaily.com/releases/2013/04/130409095414.h.
| ..
|
| https://www.discovermagazine.com/the-sciences/rapid-
| evolutio...
| asow92 wrote:
| Humanity is a part of nature and we are drivers of an epochal
| natural selection (and extinction) event. This has already
| happened and will continue to do so.
| mmoskal wrote:
| Not sure about the linked article, but the paper was also
| mentioned in last week The Economist, and it said that the number
| of tusk-less elephants was already dropping (it peaked 50% and
| now is 33%) due to conservation efforts.
| 1cvmask wrote:
| This all stemmed from the CIA (and white colonizers) involvement
| in creating the Mozambique civil war.
|
| The civil war was then partially financed by selling ivory tusks.
| Hence the culling of the elephants with tusks. The tuskless went
| untouched and managed to reproduce in larger ratios.
|
| https://www.africanexponent.com/post/4981-civil-war-in-mozam...
| bpodgursky wrote:
| Ivory poaching does not all stem from the Mozambique civil war.
|
| It stems from Ivory being expensive and these countries being
| poor with weak policing.
| slibhb wrote:
| Your decision to ascribe responsibility to "the CIA (and white
| colonizers)" for starting a war but not to the people who
| actually kill the elephants is entirely arbitrary.
| bitcurious wrote:
| There are many pre-1947 examples of Ivory in (domestic) African
| art, and the oldest piece in the world dates to ~38000BCe,
| found in present day Germany.
| christkv wrote:
| I would look at who buys ivory for the reason poaching became
| endemic
| https://www.nationalgeographic.com/pages/article/150812-elep...
| eevilspock wrote:
| Makes me wonder how human activity is evolving our very own
| genetic pool. Examples: competition vs cooperation, male vs
| female height, our immune system.
|
| We have long had a culture where men prefer mates that are
| shorter than them, and women prefer mates that are taller. This
| results in constant pressure on the pool resulting in men being
| on average taller than women. Will this change over time as we
| outgrow this rather primitive preference? (Sadly, even many
| feminist women have clung to this preference.) Not all species
| "prefer" that the male is bigger or stronger than the female.
|
| An obvious one is our reliance on modern medical technology, and
| drugs in particular. Are our bodies becoming less able to fend
| off disease?
|
| The most important one for me is the balance between those genes
| that give us our selfishness and those that give us empathy and
| love. What impact does an ever more individualistic culture and
| an economic system that defines selfishness as a virtue have on
| our gene pool?
| nyc111 wrote:
| In the Science article they wrote, "Poaching resulted in strong
| selection that favored tusklessness amid a rapid population
| decline." And, "Whole-genome scans implicated two candidate genes
| with known roles in mammalian tooth development (AMELX and
| MEP1a), including the formation of enamel, dentin, cementum, and
| the periodontium."
|
| So, there was a change in the genes, but how do they connect this
| fact with poaching? I don't see the relation. Surely, elephants
| themselves, cannot decide to change their genetics as a reaction
| to poaching.
| asdff wrote:
| It's not like evolution detects this. If you kill off all the
| blond headed people in town, all the babies next year will be
| born with brown hair. The tuskless variant was already in the
| population at some proportion, but due to tusks being a target
| of poaching, those that carry the tuskless variant are more
| likely to survive and have offspring, who are also going to
| have this tuskless variant. Over time, the population will
| shift and this tuskless variant will be present at a higher
| proportion in the overall population.
| duskwuff wrote:
| > how do they connect this fact with poaching?
|
| Poachers kill elephants for their tusks. A poacher won't kill
| an elephant with partially formed or no tusks, as it has no
| value to them. This allows elephants with the tuskless gene to
| survive and eventually reproduce where other elephants would
| not.
| bussierem wrote:
| Evolution works thanks to natural pressures -- in this case, a
| mutation in the gene gives an elephant no tusks, and thanks to
| this they are not killed by poachers. That elephant is lucky
| enough to survive to pass on its DNA. The recessive gene, over
| many generations, grows more dominant as more and more
| elephants "benefit" from having no tusks by not being hunted.
|
| So the elephants aren't reacting to poaching -- the "reaction"
| is a random mutation that happens to align with external
| pressures, causing a shift in genetics for the population.
| aaaaaaaaaaab wrote:
| Random mutations happen all the time. If there's selection
| pressure that favors a given mutation, it will proliferate.
| geoffmanning wrote:
| Just throwing it out there; i know it's scientifically
| accepted that genetic mutations are simply random and the
| ones that just so happen to be helpful are propagated by
| natural selection, but i sometimes wonder that 'random' is a
| word akin to 'magic' that describes a process we do not quite
| understand. Specifically in the context of evolution, i
| wonder if genetic mutations aren't as random as we believe it
| to be, but that life is more 'intelligent' than we give it
| credit for, and mutations are, if not always at least
| sometimes, an intentional response to changes in their
| environment. I'd be very interested to see more research in
| the way that genetic mutations may be influenced by external
| stimuli.
|
| Not an idea i deeply hold as a truth, but fun to think about,
| and science doesn't expand by believing we've got it all
| figured out.
| geoffmanning wrote:
| Surely? I wouldn't discount the power of intention when applied
| to the all too common occurrence of deep emotional stress of
| experiencing the loss of your family in such a violent display.
| drclau wrote:
| It's artificial* selection. The ones with husks die** more
| often before having offsprings, or will on average get to have
| fewer offsprings, in comparison to the tuskless individuals.
|
| *) Humans are putting the pressure.
|
| **) Are killed by poachers.
| PradeetPatel wrote:
| 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.
| rich_sasha wrote:
| I remember reading about the very thing, sold by one of the
| wildlife reserves, coming only from naturally deceased animals.
|
| There's also other species that have comparable bones.
| Supposedly, the melting permafrost is drowning the ivory market
| with mammoth ivory (which somehow is a cheap counterfeit, not
| an awesome curiosity): https://www.wired.co.uk/article/mammoth-
| tusk-hunters-russia-...
| aziaziazi wrote:
| 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.
| sva_ wrote:
| Great plan, but I'm pretty sure that people who buy ivory don't
| give a damn about elephants.
| q1w2 wrote:
| This is a fantastic question - as this is indeed done for other
| African animals, like crocodiles.
|
| The biggest issue is that elephants cannot be profitably raised
| in captivity - they require too much food, too much space, and
| take too long to produce tusks.
|
| ...and if you allow them to roam in reserves, then poachers
| shoot them. I do wonder if it might work in another part of the
| world that could offer better security for large elephant
| reserves, without them impacting the native habitat.
|
| It has also been tried with tusks obtained by elephants that
| naturally died, and that program failed due to smugglers
| bribing officials to insert poached ivory into the auctions
| [0].
|
| [0] https://www.washingtonpost.com/news/energy-
| environment/wp/20...
|
| I think the underlying issue is that demand is so high that
| there wouldn't be anywhere on Earth that could produce enough
| to stop cheap poaching in Africa, so it's easier to simply ban
| the trade entirely.
|
| Maybe there's an opportunity for lab-grown ivory? [1]
|
| [1] https://cen.acs.org/articles/96/i4/synthetic-horns-tusks-
| off...
| notriddle wrote:
| Injection-molded plastic?
|
| I kid. I kid. Obviously, injection-molded plastic is bad for
| the environment, regardless of its history as an "ethical
| source of ivory."
| bogwog wrote:
| > Researchers found the number of tuskless female elephants in
| Mozambique increased by almost double over 30 years. This
| overlaps with a period of civil conflict, where armed forces
| slaughtered 90% of the elephant population to produce ivory. This
| ivory went on to finance the conflict.
|
| People suck.
| mpfundstein wrote:
| nice generalisation. i for once never thought even remotely
| about slaughtering a freaking elephant in order to get the
| tusks. yes lots of people are bad and do bad things , but that
| does not mean that all people suck.
| SamBam wrote:
| #NotAllPeople
| [deleted]
| 1cvmask wrote:
| The civil war and conflict was created by white colonizers and
| CIA (America):
|
| https://www.africanexponent.com/post/4981-civil-war-in-mozam...
| xupybd wrote:
| Whilst I agree that this was a proxy in the cold war and that
| Colonial history messed up Africa big time, I don't
| understand what you are trying to say here?
| bordercases wrote:
| That Africans would have had no incentive to behave poorly
| were it not for whites.
| gowld wrote:
| Do you think anything else may have happened over the course of
| 30 years that may influence demand for ivory?
| boringg wrote:
| That is both fascinating and deeply sad at the same time.
| tombert wrote:
| Honest question from someone who knows virtually nothing about
| chemistry or material science: is there a difference in quality
| between synthetic and natural ivory? If not, why is poaching even
| still a viable market?
| pengaru wrote:
| When you have over a billion people in a culture valuing ivory,
| it doesn't take a large percentage of
| holdouts/morons/assholes/psychopaths to pose an existential
| threat to Elephants.
|
| Multiplication is a bitch.
| eberkund wrote:
| I imagine people view it similarly to leathers made from animal
| hides to synthetic materials. Synthetics may be better in some
| ways but people are in-part attracted by the character or feel
| that the imperfections of a natural material provide.
| jeromegv wrote:
| Leather from animal and leather from plastic is extremely
| different. It's not just the imperfection, it doesn't stretch
| the same way and the composition is fundamentally different
|
| Synthetic ivory is ivory.
| gowld wrote:
| McDonald's chicken nuggets aren't perfect ovaloids. They have
| artificial imperfections that people enjoy. (There are 4
| different molds.)
|
| You don't need natural imperfections.
| imtringued wrote:
| Isn't synthetic leather prone to flaking?
| estaseuropano wrote:
| Superstition. Elephants and tigers are not hunted for inherent
| qualities of their bodies, but for the belief that consumption
| of their parts in various ways helps health/virility/...
| bilekas wrote:
| Superstition really seems to be one of the largest factor
| when it comes to animal hunting/consumption. It's ridiculous
| and a little bit ironic that something supposedly to bring
| good fortune will result in wide scale killing of animals,
| living earthlings.
| qorrect wrote:
| It brings good fortune to the humans, not the animals.
| nickff wrote:
| > _" It's ridiculous and a little bit ironic that something
| supposedly to bring good fortune will result in wide scale
| killing of animals, living earthlings."_
|
| How is this ironic? Most cultures have prized animal
| products throughout recorded history, and many have
| practiced sacrifices, which is literally the killing of the
| being.
| lowkey_ wrote:
| Not the parent, but the irony is that to bring good
| fortune, you bring incredible misfortune (extinction,
| even) upon other living things.
| BitwiseFool wrote:
| Taking it a step further, the "value" of a sacrifice
| depends on how precious the thing is that you are
| sacrificing. Sacrificing a mouse is not the same as
| sacrificing a healthy goat.
| nickff wrote:
| It seems like the comment I responded to was referring to
| something like an 'incongruity', and saying it was
| '[situational] irony', but it doesn't really satisfy the
| definition of situational irony (from wikipedia):
|
| > _" Situational irony: The disparity of intention and
| result; when the result of an action is contrary to the
| desired or expected effect."_
|
| In this specific case, the intention of extracting animal
| products caused the animals to be killed, which is not
| contrary to the expected effect (unfortunate as it may
| be).
| bilekas wrote:
| Okay, lets give context of irony, Elephants are hunted
| for their amazing mystical power to bring good fortune to
| humans who posses their tusks.
|
| Now lets imagine the elephants actually provide a long
| distant benefit to humans, butterfly effect style. Maybe
| their migration involves knocking over some dormant trees
| with their tusks, which they're known to do, that would
| then knock over seeds for new trees. This would aid in
| the containment of soil and prevent soil erosion.
|
| Instead, consider they're all gone, the trees all die off
| without seeding, then windstorms etc turn more land into
| desert.
|
| Ironically those same hunters now have less land to grow
| food from. Thus less fortune, the action to bring more
| fortune has resulted in less.
|
| This is a stretch of an example using just 1 animal, but
| whats more confusing is why it needed to be defined
| through the purview of defining ironic.
|
| Edit: As mentioned this is 1 example, but there are an
| uncountable scenarios of 'medicinal' practices that
| require the 'rarest' animal components to 'work' from.
| Point is, its all superstition and it contributes far too
| much.
| bilekas wrote:
| See my below comment - but no 'incongruity' is something
| completely different to irony.
| [deleted]
| BurningFrog wrote:
| Has Viagra not reached China yet?
| phkahler wrote:
| Sure, but if they bleach it white and sell it as powder
| under some "Ivory" branding that will just increase
| poaching.
| BitwiseFool wrote:
| Ultimately, a good number of people will want "the real thing",
| even if it is virtually identical. There are plenty of people
| who think lab grown diamonds are illegitimate, despite having
| the exact same chemical composition as mined diamonds. For the
| rich and powerful, the Ivory is more important as a status
| symbol than anything else. Synthetic Ivory is effectively
| useless as a signal.
|
| Plus, there are people out there who sincerely believe that
| Ivory works as an ingredient in medicine and they will seek it
| out.
| bussierem wrote:
| Unfortunately (even ignoring chemistry/matsci), one of the
| answers to that is simply "natural ivory is becoming a scarce
| resource". When something is scarce, it becomes sought after,
| which can result in it even becoming a Veblen Good[1] over
| time.
|
| [1] https://www.investopedia.com/terms/v/veblen-good.asp
| tw04 wrote:
| This will probably be downvoted but the reality is it's because
| there's a ton of new money in China where they're still valuing
| things like Ivory culturally. There's no cultural stigma at
| this point. The government has banned it but the black market
| trade is still strong. See shark fin soup as another example.
| throwaway69123 wrote:
| Also if you buy the offical story of Covid it is this desire
| for exotic expensive animals with questionable natural
| medical benefits that caused the zootopic jump of Covid from
| bats to humans. So the real cost of this sort of trade now
| couldnt be higher.
| abruzzi wrote:
| as an amateur pianist, I've played pianos with and without
| ivory keys, and the feel of ivory is a bit better. I'm not sure
| why, but it seems like it doesn't get as slick from sweat as
| you play. Of course, piano keys are not the cause of current
| ivory demand to the best of my knowledge, and I'll happily take
| non-ivory keys.
| optymizer wrote:
| could it be because ivory is porous, wicking away the
| moisture?
| bluGill wrote:
| Piano makers have not used real Ivory in many years. There is
| a market for used ivory on pianos, but that is only to repair
| antique pianos. Piano makes/owners have been careful about
| this for long enough that pianos with real ivory get a pass
| because everyone understands they are dealing only with ivory
| from before we knew better.
| jsnell wrote:
| 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.
| csours wrote:
| Evolution is an umbrella term, but in the most general form,
| evolution means a change in genetics in a population over time.
| So yes, the genetic 'option' was there before, but it is
| advantageous now.
| gowld wrote:
| Evolution has two main components. The random variation was
| already there. The natural selection is doing its part now.
| what_is_orcas wrote:
| I thought evolution's components were sexual selection (who
| fucks) and natural selection (who dies). Random variation
| can change genes, yeah, but evolution is driven through the
| dis/advantages of the resulting phenotype (do they succeed
| at finding a mate, do they raise as man offspring to sexual
| maturity and do they survive long enough to do the
| aforementioned).
| [deleted]
| Hamuko wrote:
| A man with a gun doesn't sound like "natural selection".
| Spivak wrote:
| Humans are animals and predators like any other in this
| situation.
| ricktdotorg wrote:
| Why downvote parent? A human is a "natural" predator just
| with different methods of attack/more intelligence than
| "animals". Why is a human predator (an "apex predator" if
| you will) any less "natural" than a T-Rex? Or any other
| animal that forced evolutionary change?
| rsj_hn wrote:
| 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.
| klodolph wrote:
| 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".
| rsj_hn wrote:
| That is also an incoherent distinction. If humans ferment
| milk to make cheese, then this is "artificial" food? No,
| I think people use "natural" and "artificial" to mean
| "traditional practice" versus "modern practice", but
| humans do all of it.
| klodolph wrote:
| Yes, it turns out that the English language is full of
| incoherent distinctions. Words mean radically different
| things in different contexts, have definitions that are
| not really self-consistent, and tons of exceptions that
| we have to memorize. And yet, we must make sense of it to
| navigate.
|
| If I were a philosopher, or if I wrote dictionary
| entries, I might decide to spend the time to come up with
| a rather clever definition for "artificial". Feel free to
| come up with a definition yourself, if that's your fancy.
| rsj_hn wrote:
| I think the underlying bugaboo is "untested",
| particularly when referring to something considered
| "fragile".
|
| People trust traditional techniques of preparing food
| because they have proven successful at their intended
| goals. When you start messing with people's food, they
| become suspicious as to whether you know the full
| repercussions of what you are doing.
|
| So the injection of a novel element is considered
| "artificial" - despoiling the "natural" -- e.g. time-
| tested technique, and possibly disturbing something
| fragile -- e.g. human health.
|
| Similarly, people are quite reactionary when it comes to
| open spaces and nature because they see a system that
| appears to be in balance and has survived the test of
| time. They oppose altering the current state of affairs
| because they are sure some unintended side effect will
| screw things up.
|
| On the one hand, it's laudable to have these goals, but
| if they used the standard language of conservatism,
| traditionalism, etc, they would be branded as
| reactionaries, so the spirit of the age is to invent new
| words like "artificial" and "natural" that are less
| loaded with politics, even though it is all just
| conservatism at its roots.
| allturtles wrote:
| "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/arti
| ficial-s...
| kuhewa wrote:
| There are more main components than that. Sometimes forces
| like drift are stronger than adaptive selection.
| klodolph wrote:
| This is selective breeding / artificial selection, not
| natural selection.
| NovemberWhiskey wrote:
| No, it's not. People are not choosing pairs of elephants
| to breed.
| klodolph wrote:
| It may be unintentional, but it is still artificial.
| imtringued wrote:
| You're saying poachers intentionally breed tuskless
| elephants so they don't have to hunt anymore?
| qorrect wrote:
| ... Evolution has three main components
| thaumasiotes wrote:
| Sure, and two of them are identical from every practical
| and theoretical perspective.
| phkahler wrote:
| If it were some other predator, we'd say it's natural
| selection. Because it's humans killing the ones with
| certain traits we say it's artificial? But humans are not
| doing it to promote a certain trait, in fact the
| evolutionary effect of the poaching is actually the
| opposite of what people want.
| bialpio wrote:
| Except it's only advantageous to female elephants, according
| to the article:
|
| "They identified two likely genes AMELX and MEP1a, which are
| passed from mothers to the offspring on the X chromosome. But
| if a disrupted gene is passed in a male elephant, the
| elephant dies; the female elephant would instead evolve to be
| born without tusks. "
|
| What would be the effect of this on male elephant population
| when taken to the limit (i.e. 100% of females are tuskless)?
| Seems to me that it'd skew the proportion of births towards
| 2:1 (assuming it's now at 1:1)? How significant impact would
| that have to the species as a whole?
| lvass wrote:
| Warning: guesswork. If only females survive with this
| disruption, it can only be inherited from a mother, so only
| 1 X chromosome of a female can have it. If somehow only
| those females survive, there's a pool of 50% of X
| chromosomes of females with the mutation. The following
| generation would be born with half of the female population
| with the mutation (25% of female X chromosomes), and half
| of the male population dead. The following one, without
| artificial selection, would have a fourth of mutated
| females and dead males. So this mutation tends to just
| disappear without selective pressure.
|
| So while a tuskless female may generate 2:1 females to
| males, that's (hopefully, depending on poaching) far from a
| stable birth ratio for the population, though active
| poaching may cause the female to male ratio for living
| specimens can be further skewed much higher than 2:1.
| esturk wrote:
| Maybe not as much as you would think. Naturally, not all
| males mate and the mating ratio is not always 1:1. Take
| humans for example, it's been shown our ancestors comprise
| mostly of females in a ratio roughly 3:2 to males. That is,
| some male ancestor probably mated with more than one female
| ancestor somewhere.
| AussieWog93 wrote:
| >our ancestors comprise mostly of females in a ratio
| roughly 3:2 to males.
|
| For anyone else wondering how this is possible on an
| individual level, apparently a lot of people used to
| reproduce with their first and second cousins.
| caymanjim wrote:
| I don't know what the numbers are like for elephants, but
| in many species, most males don't get to mate at all, and
| a handful of dominant males mate prodigiously. Even if
| tuskless males were viable, they'd fail miserably at
| mating if there were tusked males around, because they'd
| get their asses kicked.
| thaumasiotes wrote:
| > it's been shown our ancestors comprise mostly of
| females in a ratio roughly 3:2 to males.
|
| I thought it was 2:1.
| VeninVidiaVicii wrote:
| And this is why genetic diversity is a good thing.
| micromacrofoot wrote:
| Yes, but in the long run isn't this breeding out this
| specific diversity? I recall reading that genetic diversity
| becoming limited in endangered species makes them much more
| susceptible to being wiped out by disease.
| rustyminnow wrote:
| Hmm in the context of the article, I'm not so sure it's a
| good thing.
|
| Later on they mention that if this genetic trait gets
| passed on to males, they die. So along with hunting, males
| are doubly at risk.
|
| It may be advantageous for the survival of an individual to
| be born without tusks, but it doesn't sound too good for
| the survival of the species.
| hanniabu wrote:
| Why do they die? Because they can't protect themselves?
| Or does the trait come with other less desirable side
| effects for males?
| jbay808 wrote:
| The trait appears to be lethal to males and they do not
| make it to birth.
|
| It may be the case that at least one typical X chromosome
| is necessary for survival, and males only get one X
| chromosome.
| netcan wrote:
| The trait may or may not be advantageous. Diversity is.
| In this case the selective pressure is poaching, but
| selective pressures are constant. Diversity is a bank of
| genetics that the population can draw from to adapt and
| survive.
|
| Traits that are rare, are often rare because of
| shortcomings. But if environmental changes make that
| tradeoff worthwhile, it can be made. Meanwhile, evolution
| doesn't stop. Once the trait/gene is common there is
| positive selective pressure on complementary genes. Over
| time, these may mitigate or compensate for the negative
| traits that have acquired.
|
| Of course, on the timescales that humans tend to
| selectively pressure species, there isn't time for all
| this elegance to emerge, usually.
| rustyminnow wrote:
| This is all true. You make very good points.
|
| My parent said:
|
| > And this is why genetic diversity is a good thing.
|
| I guess what I meant was: genetic diversity is a good
| thing. But this particular case is not a great example
| for illustrating why.
| ehsankia wrote:
| Not only is it more advantageous, it actually was force
| selected for (IIRC, poached elephants are often left for
| dead). So this is closer to selective breeding/artificial
| selection more so than natural selection.
| cromka wrote:
| That's precisely what the article linked points out.
| jbattle wrote:
| What's the difference in this case? Doesn't seem too
| different from how camouflaged eggs would have developed
| (maybe just faster because the selection mechanism is so
| strong).
|
| When I think of selective breeding I think of humans
| picking out which animals (cows/dogs/wheat/etc) get to
| reproduce.
| mfer wrote:
| 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.
| jawarner wrote:
| 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.
| mfer wrote:
| 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
| MAGZine wrote:
| 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).
| meej wrote:
| 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
| imtringued wrote:
| You don't have to change genes to change their presence
| in animals.
|
| It's like market share. More users can simply download
| your software and you can gain market share without
| releasing an update.
| comrh wrote:
| That's natural selection
| if_by_whisky wrote:
| it's selection, more precisely
| [deleted]
| hanniabu wrote:
| That's how it always is. It starts from somewhere and then
| somewhere along the line that fringe trait becomes
| desirable and then more widespread.
|
| Like others said, it's evolution + natural selection. In
| this case the evolution part came long ago and now natural
| selection is making it more prevalent.
| dan_mctree wrote:
| Is anyone else surprised at how quick species can seem to
| evolve in these kinds of ways? Asian and African elephants are
| supposed to have separated millions of years ago, yet still
| strongly resemble one another. Yet in a few decades, something
| as fundamental as the presence of their tusks can shift
| dramatically. And that in a species with very long gaps between
| generations.
|
| It makes me suspect there's something else going on here that's
| not just good old natural selection.
|
| Have they done any tracking to confirm the tuskless elephants
| are actually being born to tuskless mothers? Or could it be
| that the parents are actually affecting the way their offspring
| are born in some lamarckian-esque sense? If there'd be some
| trick animals can pull to change their offspring in some ways,
| that ought to be highly effective for long term species
| survival and should thus be highly selected for.
| q1w2 wrote:
| A point evolution event can happen extremely rapidly if
| there's a clearly selective mortality event.
|
| If a new predator is introduced to a population that
| selectively kills only certain traits, that mutation can
| become dominant in the population within just one or two
| generations.
|
| Imagine if aliens came to Earth and killed everyone over 5'6"
| tall. That "evolution" would be essentially instantaneous.
| formercoder wrote:
| Seems like the relative death rates of tusked vs tuskless
| would matter. Remember the 32% is a percent potentially on a
| small number. Say to an extreme 99% of tusked elephants were
| killed, 99% of tuskless were unharmed. If tuskless is a
| genetic traight, it takes over very quickly even though total
| population size is smaller.
| psyfi wrote:
| Exactly that!
|
| I think it is ridiculous to think that more elephant are
| born without tusks as a kind of "random selection" or even
| adaption
| imtringued wrote:
| What do you mean by quick? Evolution is just random
| mutations. You're basically trying to diversify and spread
| risk. If there is huge selective pressure only a handful of
| genes will survive and when they reproduce they will be over
| represented compared to the previous generation.
| burnished wrote:
| Nah, looks like natural selection. The article mentions that
| "The phenomenon of elephants going tuskless is not new.
| Researchers found the number of tuskless female elephants in
| Mozambique increased by almost double over 30 years. This
| overlaps with a period of civil conflict, where armed forces
| slaughtered 90% of the elephant population to produce
| ivory.". That is a LOT of selection pressure. Also, the
| African Elephant Specialist Group (AfESG) [1] published a
| graph of elephant populations, the reduction in total numbers
| is pretty dramatic. You might liken this to the way that
| humans in small, isolated communities will also start to
| differentiate in a hurry (forex, that one blue family).
|
| [1] https://ourworldindata.org/grapher/african-elephants
| tim-- wrote:
| I mean this honestly, but what is the blue family that you
| are talking about. The first thing that springs to mind is
| Avatar, and Google isn't helping me out.
| drtz wrote:
| > 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.
| jbay808 wrote:
| Further to your point, I read elsewhere that the base rate in
| captivity is closer to 0.5%.
| dheera wrote:
| As sad as this is, how does this kind of evolution happen?
|
| I imagine the poaching process doesn't actually differentiate
| tusked and tuskless elephants, both types of elephants would
| fall into the trap and die? And then if it has tusks the
| poachers take them, if it doesn't have tusks the poachers just
| abandon the dead elephant?
|
| Or does their trap actually trap them by the tusk?
| jsnell wrote:
| They're hunted interactively by people with guns, not
| passively with traps.
| cabalamat wrote:
| Traps wouldn't work because the authorities would get to
| the elephant in a trap before the poacher returned, thus
| the poacher would lose their prey.
|
| The poacher could always hang around near the trap, but if
| you're doing that you might as well just shoot the
| elephant, not trap it.
| varenc wrote:
| Yea I assume poachers shoot elephants, not trap them. So they
| only want to shoot ones with visible tusks.
|
| Edit: I found an article[0] describing some poaching methods
| and apparently they do use traps! Including snares and a
| spiked board. But that it appears homemade shotguns and
| rifles are the most common method.
|
| [0] http://www.open-
| earth.org/document/natureR_main.php?natureId...
| Ansil849 wrote:
| For people who are not from the region but are criticizing
| poaching...maybe you should make sure your own house is clean
| before throwing stones at others. How many people critiquing this
| have industrial animal farms in their country, for example?
|
| And just to be clear: I don't mean that vile acts like poaching
| shouldn't be criticized, I more find the hypocrisy extremely
| grating, especially when it comes from meat eaters.
|
| And ah yes, the downvotes. Sorry, but if you eat animals and yet
| critique poaching, then you are a hypocrite who does not give a
| fuck about animal welfare (because if you did, you wouldn't kill
| them).
| geoffmanning wrote:
| Somewhat of a good point, however, life sustains life. Not
| quite the same thing as killing an animal for some made up
| concept like money. That said, i personally don't eat mammals
| because i feel like they have too much in common with us, and
| science is learning more and more just how much so. I do eat
| birds and fish.
| ceejayoz wrote:
| > Sorry, but if you eat animals and yet critique poaching, then
| you are a hypocrite who does not give a fuck about animal
| welfare (because if you did, you wouldn't kill them).
|
| "The Good Place" covered this attitude a bit, with the Doug
| Forcett character, and showed the horrible implications of "you
| can always be doing more" as a guiding principle in life.
| Ansil849 wrote:
| There's a world of difference between feeling that "you can
| always be doing more" and criticizing poaching on the
| internet an hour before sitting down to enjoy a steak dinner.
| seattle_spring wrote:
| Are cows an endangered species?
| Ansil849 wrote:
| What is your point? That it's acceptable to kill or
| otherwise maim creatures which are not endangered, like,
| say, humans?
| ceejayoz wrote:
| There's a potential ethical difference between wiping
| out, say, a bee hive and wiping out bees as a species,
| yes.
| Ansil849 wrote:
| Except that's not what the question I was responding to
| is implying. It seems to be implying it is OK to be doing
| harm to species which are not endangered.
| seattle_spring wrote:
| Yes, killing a non-endangered animal for sustenance is
| more acceptable than killing an endangered animal for a
| necklace pendant (or any other reason). Any other
| questions?
| Ansil849 wrote:
| So you don't see the absurdity of this? At all? You're
| literally saying killing people is more acceptable than
| killing elephants.
| ceejayoz wrote:
| You don't know who in this thread might be doing that. Some
| HNers are undoubtedly vegans/vegetarians. Some might be
| getting their beef from a local farmer raising them on
| pasture. Others may hold specific concerns about the
| extinction of an entire species that doesn't apply to cows.
| lostlogin wrote:
| Arguing this way won't get people to agree or to change. It's
| also a bit of a stretch to link meat in one's diet to ivory
| poaching.
| tjpnz wrote:
| I've been a vegetarian my whole life yet find this argument
| nonsensical. The animals being poached are in many cases on the
| verge of extinction, the animals raised on industrial farms are
| not. While I do find the idea of killing animals abhorrent the
| industrial process is significantly more humane than what
| happens to poached animals, which are typically left to slowly
| bleed to death or are permanently maimed.
| pessimizer wrote:
| One can care about biodiversity and the preservation of
| environments without caring at all about individual animal
| welfare. Maybe I want to preserve species because I want to eat
| more varieties of meat.
| technothrasher wrote:
| Poaching is unregulated and ends up with animals going extinct.
| People who eat common meat animals are, in fact, doing the
| exact opposite and pretty much ensuring those animals don't go
| extinct.
|
| You may have good reasons to find meat eating morally
| objectively objectionable, but eating meat and complaining
| about poaching is not a hypocritical position.
|
| The rest of your post is simply a relative privation fallacy.
| ff317 wrote:
| > pretty much ensuring those animals don't go extinct.
|
| Sort of, but you have to add some nuance here. None of the
| animals we commercially farm in mass quantities for food are
| "natural" animals to begin with. They were bred down (in some
| cases over many centuries) from their natural ancestors to be
| a perfect food animal for humans. Some probably wouldn't
| survive (as a species) in the wild if the humans were gone.
| The ancestor species in many cases are already lost. More
| importantly, significant amounts of previously-wild
| ecosystems are now turned into commercial farming operations
| just to feed all these artificial animals, robbing habitat
| from the remaining more-natural animals.
|
| I still eat meat. I just think it's important to not be naive
| about what's going on here. We've already largely terraformed
| what used to be the wild Earth into a custom-tailored bio-
| mechanical ecosystem designed to amplify human population
| potential. There are, unfortunately, not many great ways to
| fix it at scale without massively reducing our population
| first, and it's debatable whether we should even try.
|
| A related notion is that most of what we call
| environmentalism isn't really about saving the natural state
| of the Earth (whatever you define that as!), it's about
| stopping our ecosystem engineering from going off the rails
| in directions that will ultimately doom us (climate change,
| massive pollution, etc). The Earth will be fine either way:
| if we manage to off ourselves through stupidity on
| environmental issues, nature will just go back to being
| nature again.
|
| Relevant XKCD: https://xkcd.com/1338/
| cure wrote:
| > For people who are not from the region but are criticizing
| poaching...maybe you should make sure your own house is clean
| before throwing stones at others. How many people critiquing
| this have industrial animal farms in their country, for
| example?
|
| While I somewhat understand the sentiment, this is obviously a
| completely impractical attitude.
|
| If you follow this logic nothing is ever going to change,
| because let's face it, nobody is perfect. We're all human.
|
| I'm not a meat eater, but I am very happy that meat-eaters
| critique poaching. This is a win, as it can only lead to more
| awareness of how we treat animals. Maybe it will make some more
| people give up meat.
| cabalamat wrote:
| > Relentless ivory hunting over decades has caused elephants to
| evolve in a way we never imagined them to.
|
| This is only true if "we" have very little imagination.
| [deleted]
| chiefalchemist wrote:
| > Published in Science on Thursday, the study looked at the
| genetic changes engineered due to mass poaching for ivory.
|
| This interpretation of evolution is a myth that needs to be
| busted. Nothing is being "engineered". What is happening is
| simply: no tusks is an advantage. That is, no tusks means less
| likely to be hunted / killed.
|
| As a result, the tusk genes in the gene pool are less available.
| The no-tusks genes more.
|
| In short, and ultra-simplified, evolution is reactive.
| mulmen wrote:
| 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.
| TehCorwiz wrote:
| 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.
| engineer_22 wrote:
| 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.
| unclekev wrote:
| > Neither do we say that chihuahua's and labradors have
| evolved into their present form.
|
| They 'evolved' into their present forms because they were
| forced/accelerated by the hand of humans through selective
| breeding.
| ninkendo wrote:
| We already have a term for speciation though. Evolution is
| more broad.
| hcarvalhoalves wrote:
| 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.
| smk_ wrote:
| Selective breeding is one form of evolution.
| ChrisArchitect wrote:
| Only the _fourteenth_ story about this in the past week on here
| gpt5 wrote:
| While sad as a whole, the responsiveness of evolution is
| beautiful in this case.
|
| It also demonstrates that human efforts to stop poaching have not
| been successful (otherwise this evolution wouldn't happen), but
| luckily, nature responds.
| phkahler wrote:
| It's also interesting that a single mutation can cause this
| lack of tusks. That reinforces another concept for me - the
| ability to adapt is also important and has been selected for.
| Meaning simple genes to define structure are preferable to
| complex sets of them.
|
| On a related note, if "ability to evolve" is a characteristic
| that can be selected for that would explain why all complex
| life uses sexual reproduction. Mixing genes offers such
| advantages that most everything that can't do it is still
| basically bacteria.
| what_is_orcas wrote:
| > It's also interesting that a single mutation can cause this
| lack of tusks. That reinforces another concept for me - the
| ability to adapt is also important and has been selected for.
| Meaning simple genes to define structure are preferable to
| complex sets of them.
|
| I wouldn't get too attached to that idea... in a lot of
| cases, having one gene responsible for producing a phenotype
| can be a very bad thing, like oncogenes (responsible for the
| growth of cancers) and a bunch that determine development
| and/or aging.
|
| > On a related note, if "ability to evolve" is a
| characteristic that can be selected for that would explain
| why all complex life uses sexual reproduction. Mixing genes
| offers such advantages that most everything that can't do it
| is still basically bacteria.
|
| Again, sometimes. There are lizards and bugs that clone
| themselves (parthanogenesis) which can be really handy for
| when the population isn't doing so hot.
| redleggedfrog wrote:
| It's too bad there is not a gene for making the tusk highly
| radioactive or shoot out like rockets at the poachers. I guess
| that's asking a lot of evolution - it's already done a lot for
| us.
| UnFleshedOne wrote:
| lol, elephants would be wiped out in a few years if they
| start doing something like that. First rule of dealing with
| humans is not to be too effective at it.
| geoffmanning wrote:
| Not sure 'beautiful' or 'lucky' are words i'd use to describe
| it. Did you catch that the males of tuskless mothers generally
| don't survive, decimating the male population? It's a tragic
| and desperate response, though quite incredible that such a
| dramatic evolutionary trait can occur. It makes me wonder what
| we could become, if only...
| _jal wrote:
| > if only...
|
| If only humans were harvested for bony growths?
| kuratkull wrote:
| Tusks are not bones
| geoffmanning wrote:
| LOL. Yes.
| vmception wrote:
| Beautiful, lucky, bad
|
| Incredible, good
| geoffmanning wrote:
| Not quite sure what you're getting at. The definitions of
| those words can't simply be categorized as good or bad.
| Beautiful and lucky do, however, somewhat infer a positive
| outcome in the context they were used. Incredible infers
| neither positive nor negative. It means that it's simply
| extraordinary that such a thing could occur, outside the
| bounds of previous beliefs.
| vmception wrote:
| I personally find the natural selection process to be
| beautiful to witness, the adaptive pressures to be
| incredible, and the cause to be tragic
|
| Not mutually exclusive
| geoffmanning wrote:
| Context matters.
| vmception wrote:
| It never needed elaboration even from the person you
| initially replied to.
| geoffmanning wrote:
| Yet here we are. Thanks for contributing.
| [deleted]
| teeray wrote:
| Life, uh, finds a way...
| cabalamat wrote:
| Maybe the males will evolve ways to survive with the
| tusklessness gene.
| officialjunk wrote:
| but the tusks had a purpose to defend and now they are
| defenseless.
| asdff wrote:
| Stomping is a common way for elephants to deal with
| predators. Tusks are used a lot as a tool though.
| croes wrote:
| If the probability to get killed for the tusks is higher than
| get killed by predators then it's an advantage.
| ceejayoz wrote:
| There are short-term and long-term advantages and
| disadvantages, though.
|
| From the article, it sounds like this may have protected
| them from human predation, but there may be significant
| long-term negative impacts on the species due to the lack
| of viable male offspring.
|
| Survive more easily for a couple generations, but go
| extinct as an all-female species after a couple more...
| kadoban wrote:
| What do the males die of exactly? Not clear to me.
| ceejayoz wrote:
| Seems like the mutation kills male embryos.
|
| https://www.science.org/doi/10.1126/science.abe7389
|
| > Survey data revealed tusk-inheritance patterns
| consistent with an X chromosome-linked dominant, male-
| lethal trait. Whole-genome scans implicated two candidate
| genes with known roles in mammalian tooth development
| (AMELX and MEP1a), including the formation of enamel,
| dentin, cementum, and the periodontium. One of these loci
| (AMELX) is associated with an X-linked dominant, male-
| lethal syndrome in humans that diminishes the growth of
| maxillary lateral incisors (homologous to elephant
| tusks).
| imtringued wrote:
| Why is it possible for us to have a 50:50 gender ratio?
|
| Why haven't mothers that only give birth to girls taken
| over the world? Do unpaired girls really die that
| quickly?
| cromka wrote:
| I am not sure you read the article, because the number of
| large-scale side effects this single evolutionary treat evokes
| is in rather starting contrast with your "the responsiveness of
| evolution is beautiful in this case."
| asdff wrote:
| Its important to realize what this "response" actually is.
| Nature isn't actively doing anything. You have 100 elephants,
| maybe 5 are typically born without tusks. Suddenly you kill the
| other 95 for their tusks, leaving behind those 5 to survive and
| reproduce and next generation, 33 of your 100 elephants are
| without tusks or something like that. Over time, humans are
| acting as a predator in the environment, driving a selective
| pressure that reduces the fitness of the tusk trait relative to
| the no tusk trait
| lowkey_ wrote:
| I think the above commenter recognized that; that's exactly
| how these evolutions pretty much always work in nature, not
| unique to this case.
| ehsankia wrote:
| Right, but "natural selection" generally doesn't include
| human influence, but that's semantics. Would you also say
| that fruits that are selectively bred to be bigger and
| juicier are also under the influence of "natural
| selection"?
| marginalia_nu wrote:
| Humans aren't some supernatural force. We're very much a
| part of nature as well.
| ehsankia wrote:
| I agree, but we also make the very language we're using
| to describe stuff, and sometimes it's useful to
| differentiate some things. Very often, it's useful to
| separate human-caused and non-human caused impacts, such
| as with climate change.
| lowkey_ wrote:
| I wouldn't, because a fruit bred to be bigger and juicier
| is engineered by humans for their own benefit, while an
| elephant evolving to not have tusks is evolution going
| against human benefit.
|
| I believe natural selection includes the influence of any
| species related to the species in question as predator or
| prey, and humans in this case are predators. We may
| historically be responsible for far more processes of
| natural selection than we're aware of!
|
| You're right that it's exceedingly rare to see us so
| directly play a role in natural selection today (as
| opposed to indirectly through affecting the environment),
| which makes this very interesting.
| isoskeles wrote:
| I'm not sure where the distinction between "natural" or
| "artificial" selection is, or if it matters. But it seems
| clear that humans and our technology are capable of
| creating far more pressure for other species to either
| evolve or die if we target them for some reason.
|
| If it weren't for us hunting these elephants for their
| tusks, there isn't a reason they'd evolve in this manner.
| So I just wouldn't call that evolution by natural
| selection. Same thing if we set off to exterminate all
| mosquitoes.
|
| But I do get your point. I'm conflicted if we can count
| ourselves as any other predator species when discussing
| evolution.
| evolution_1 wrote:
| > "natural selection" generally doesn't include human
| influence
|
| It absolutely can. Artificial selection is just a form of
| natural selection where the environmental pressure is
| human breeding.
| croes wrote:
| Nature is never doing anything.
| elwell wrote:
| This is both true and false.
| xwdv wrote:
| Of course, because "nature" doesn't actually exist, it is a
| concept in the human mind. There is only matter and physical
| law. What we are simply witnessing is individuals with
| certain genetic traits surviving in far greater numbers than
| those who lack them in the current environment, and thus
| passing those same genes to offspring, propagating them
| exponentially.
| lmilcin wrote:
| Put this in context of a lot of other species who were not able
| to evolve a mechanism like that.
|
| The way I understand this there was likely a very small
| population of elephants already without tusks, maybe some kind
| of genetic defect that happened to be an advantage once you add
| greedy people into the mix. Or what else is possible is that
| there was one off mutation that produced small family of
| elephants that poachers wouldn't touch and these spread over
| decades.
|
| Think about this, if today Covid mutated to kill almost all
| people but spared 0.1% with a certain gene, you would suddenly
| observe entire human population becoming immune to Covid.
|
| This does not necessarily mean any new genetic material or
| "nature responding". Maybe nobody noticed the gene and it
| suddenly became very visible and comprising large part of
| population (while it declined dramatically as elephant
| population did). We may have missed elephants without tusks
| because they were just freak of nature but now they become
| proliferating because it becomes an advantage.
|
| EDIT:
|
| Selective pressure is part of evolution process, but it is not
| enough for evolution.
|
| Evolution requires both mutation AND selection.
|
| So, if the mutation was present BEFORE poachers happened, you
| can't really say that Mother Nature RESPONDED to poaching by
| evolving new mechanism. The word "response" implies causal
| relationship between poachers and mutation+selection of better
| equipped elephants. But if the mutation has already been
| present then there is no causal relationship and this wasn't a
| new mechanism.
| jalgos_eminator wrote:
| > This does not necessarily mean any new genetic material or
| "nature responding".
|
| But this is exactly how evolution works. There are always
| mutations in every generation, and sometimes those mutations
| are beneficial. These genes are being selected by the
| organism's environment, and if the environment changes, then
| the genes that are selected will be different. That is
| "nature responding". Elephants without tusks (or very small
| ones) are more likely to survive and produce offspring.
| KiranRao0 wrote:
| I would argue what you describe is Evolution as broken into
| the two pieces: Genetic Drift and Natural Selection.
|
| Genetic Drift is always occurring randomly. Some elephants
| had a "genetic defect" to live without tusks before poaching.
| Some humans had the 0.1% resistance to the hypothetical
| super-covid before the disease.
|
| As new environmental conditions emerge (human poaching,
| hypothetical super-covid, etc), some genes are far better
| adapted to the new environment (tuskless, covid resistance,
| etc). Those genes then thrive in the new environment and
| consume the available resources left by those killed off.
| [deleted]
| addicted wrote:
| > What I mean is that it is possible (and I think very
| likely) this isn't feat of nature suddenly evolving some
| new defense mechanism as response to poachers.
|
| That's not how evolution works. Evolution doesn't ever
| involve a "feat of nature suddenly evolving defense
| mechanisms".
|
| I don't understand this comment, unless it's a way to say
| the above, that evolution does not involve sudden
| spontaneous changes in response to an external stimuli.
| mysterydip wrote:
| 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?
| BitwiseFool wrote:
| 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
| sites.
|
| Interestingly enough, there was a creature that very much looks
| _like_ a unicorn, but it is a rhinoceros and not an equine.
|
| https://en.wikipedia.org/wiki/Elasmotherium
| Apocryphon wrote:
| There's also no cultural record of legends of "unicorn hunts"
| unlike say hunting the white stag.
| mysterydip wrote:
| There are plenty of stories of unicorns, though. Why them
| and not some other animal?
| Apocryphon wrote:
| There are plenty of stories of dragons, too.
| theduder99 wrote:
| 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..
| pm215 wrote:
| I think we'd expect to see vestiges of the no-longer-outwardly-
| visible horn in the skeleton and perhaps during fetal
| development, like with human tails.
| gowld wrote:
| Unicorns don't exist because they were arrogrant, unserious
| creatures who refused to fall in line with the other animals:
|
| Source:
| https://www.google.com/search?q=shel+silverstein+unicorn
| Apocryphon wrote:
| Where are all of the heirloom artifacts made from unicorn
| ivory?
| [deleted]
| xupybd wrote:
| The fossil record.
|
| If they were hunted then there might be a cultural record as
| well.
| gpm wrote:
| On the topic of unicorns existing...
|
| > There are wild elephants in the country, and numerous
| unicorns, which are very nearly as big. They have hair like
| that of a buffalo, feet like those of an elephant, and a horn
| in the middle of the forehead, which is black and very thick.
| They do no mischief, however, with the horn, but with the
| tongue alone; for this is covered all over with long and strong
| prickles and when savage with any one they crush him under
| their knees and then rasp him with their tongue. The head
| resembles that of a wild boar, and they carry it ever bent
| towards the ground. They delight much to abide in mire and mud.
| 'Tis a passing ugly beast to look upon, and is not in the least
| like that which our stories tell of as being caught in the lap
| of a virgin; in fact, 'tis altogether different from what we
| fancied
|
| - Macro Polo
|
| https://en.wikisource.org/wiki/The_Travels_of_Marco_Polo/Boo...
|
| They're hunted for their horns too...
|
| https://en.wikipedia.org/wiki/Rhinoceros#Ways_to_prevent_poa...
| Rphad wrote:
| This reminds me of this study that polled academics and students
| about the evolutive process that happens. The results are quite
| decieving. https://journals.openedition.org/ress/2698
| SamBam wrote:
| For those who don't want to read a long French article: the
| conclusion (as I understood it) is that most people imagine
| teleological, or goal-driven (the authors describe it as
| "finalist") reasons for this very change in tusks. That is,
| even when the subjects consider that poaching may be the cause
| in the change in tusk allele frequency, they say it's because
| the elephants "want" not to have tusks, or that evolution is
| "deliberately" evolving away from tusks in order to protect the
| elephants.
|
| This is in contrast to the actual explanation, which is simply
| that if you kill the elephants with the tusks alleles and
| prevent them from breeding, you'll have fewer of those alleles
| in the subsequent generations.
|
| I'd say this result is not so "deceiving," as someone who has
| prepared evolution curriculum in the past, the teleological
| explanation is extremely seductive, even for educated people.
| ygmelnikova wrote:
| Similar results with my Drosophila in grade 9.
| beebmam wrote:
| With discussions around evolution, I try to keep in mind that the
| main pressure for evolution is from natural selection, and
| natural selection works on death. Plenty of species have been
| "naturally selected" for total extermination.
|
| It's difficult to keep ethics out of discussions when facing the
| reality of life: that there is a massive amount of death and
| suffering, and it's a terrifying thing we're all forced into,
| including these elephants.
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