# When Humans Thwart Evolution-What Happens? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [October 5, 2015, 1:57pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609 "2015-10-05T13:57:47Z")\ **Posts on this page:** 19\ **Page:** 2
**Author:** ![The\_Hamster\_King](https://avatars.discourse-cdn.com/v4/letter/t/8edcca/32.png) [@The\_Hamster\_King](https://boards.straightdope.com/u/The_Hamster_King)\ **Post date:** [October 6, 2015, 6:12pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/21 "2015-10-06T18:12:57Z")
> [@ralph124c](#): > > A Ginko tree is very primitive-if we “rescue” it from its (deserved) extinction, are we crowding out a more complex type of tree? The “primitive” Ginko tree is out-competing your hypothetical “more complex type of tree”. The Ginko’s evolutionary strategy is “be appealing to humans”, and in an environment where humans have a huge influence, that’s a very sensible strategy to adopt. The more complex tree chose its strategy poorly. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [October 6, 2015, 7:43pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/22 "2015-10-06T19:43:49Z")
> [@The\_Hamster\_King](#): > > The “primitive” Ginko tree is out-competing your hypothetical “more complex type of tree”. The Ginko’s evolutionary strategy is “be appealing to humans”, and in an environment where humans have a huge influence, that’s a very sensible strategy to adopt. The more complex tree chose its strategy poorly. As others have pointed out, there’s no strategy or choice involved. It’s just random mutations. Ginko trees just got lucky and happened to have a random mutation which resulted in them being more attractive to humans. ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [October 6, 2015, 8:11pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/23 "2015-10-06T20:11:28Z")
> [@ralph124c](#): > > But it seems that evolution gives rise to more complex forms of life. A Ginko tree is very primitive-if we “rescue” it from its (deserved) extinction, are we crowding out a more complex type of tree? How is a ginko “primitive”? For that matter, how is a bacteria “primitive”? Both species have had just as many years in which to evolve as we have. You can argue a human or ginko is _more complex_ than a bacteria, but they are no “more evolved”. And why do you say a ginko “deserves” extinction? They’re actually pretty darn hardy trees, which is one reason they survived long enough to meet up with humans that want to preserve them. They may not have changed much the last 50 or 100 million years, but that probably means they’re just a good pattern for a living organism. ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [October 6, 2015, 8:57pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/24 "2015-10-06T20:57:17Z")
> [@ralph124c](#): > > Species evolve, flourish, then die out. that is evolution. My question: when humans interfere with this, what are the results? take for example the Ginko tree-the species has been in decline for millions of years, but humans have 'rescued" these trees, and transplanted them to almost every inhabited country. they had been reduced to a very small change in the mountains of China, and hence vulnerable to extinction. > Or the species Canis Familiaris-there are probably 100’s of millions of dogs alive today, compared with a few thousand wolves. > When man interferes with the natural process of evolution, are the results good or bad? > Now we are contemplating bring back long-extinct species (like the Tasmanian Wolf and the Giant Mammoths-will these efforts make the world better or worse. This is an excellent question, and the answer is that it will make the world better. Please do not hesitate to ask if you have further questions on this matter. ---
**Author:** ![PatrickLondon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/patricklondon/32/4422_2.png) [@PatrickLondon](https://boards.straightdope.com/u/PatrickLondon)\ **Post date:** [October 6, 2015, 8:59pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/25 "2015-10-06T20:59:03Z")
> [@swampspruce](#): > > My personal belief is that adding variety tends to make the whole system more robust overall; Monocultures on a large scale tend to be detrimental over the long haul. I call it the Joni Mitchell principle - you don’t know what you’ve got till it’s gone. ---
**Author:** ![Icarus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/icarus/32/72_2.png) [@Icarus](https://boards.straightdope.com/u/Icarus)\ **Post date:** [October 6, 2015, 9:23pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/26 "2015-10-06T21:23:18Z")
> [@dracoi](#): > > Huh? > > “Adapted to the environment” means nothing in evolution except “successful mating.” > > It may well be that “survival of the fit” in modern humans favors “too stupid to use birth control.” Evolution has no problem with that. It’s only us silly humans who think there is an inherent advantage to being smart, strong, agile and self-controlled. I respectfully disagree. One must first mature to a fertile age. This requires avoiding being eaten, or befalling some other fate. So, I stand by my assertion that being adapted to the environment is separate from successfully mating. ---
**Author:** ![msmith537](https://avatars.discourse-cdn.com/v4/letter/m/d9b06d/32.png) [@msmith537](https://boards.straightdope.com/u/msmith537)\ **Post date:** [October 6, 2015, 9:27pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/27 "2015-10-06T21:27:33Z")
> [@WordMan](#): > > I thought this thread was going to be about the % of humans who are alive right now who wouldn’t be without human intervention. It feels like we are extending a “plank of survivability” out past what natural processes would typically support. ISTM we are taking a further step out onto that plank with every generation, and perhaps at a faster pace, e.g., internet natives who rely much more on their online lives than non-natives. When there are disasters and other events it feels like I can see that plank just cut off for the affected population. It’s not really a “plank” as that implies a sort of linear continuity. A flash flood or meteor, for example, is not going to wipe out all the humans who do not meet a particular genetic profile (i.e. being a certain height or weight). It will wipe out humans who fit a particular geographical location. IOW, a larger and more diverse the human population does not make us more prone to extinction, it makes us less. At least for extention events not related to having too many people on the planet. ---
**Author:** ![Yllaria](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/yllaria/32/3452_2.png) [@Yllaria](https://boards.straightdope.com/u/Yllaria)\ **Post date:** [October 6, 2015, 9:36pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/28 "2015-10-06T21:36:03Z")
> [@dracoi](#): > > I’m still mad about algae and all that damn oxygen they dumped into the atmosphere. Don’t they know how many species they killed off? Evolution hasn’t been done right for the last billion years. > > But that’s all spilled milk. In the meantime, I’m setting up a “free the mitochondria” petition. Golf clap. ---
**Author:** ![dba\_Fred](https://avatars.discourse-cdn.com/v4/letter/d/c37758/32.png) [@dba\_Fred](https://boards.straightdope.com/u/dba_Fred)\ **Post date:** [October 8, 2015, 5:30pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/29 "2015-10-08T17:30:20Z")
\*You say you want some evolution Well, ya know We all want to populate the world You tell me that’s it’s revolution Well, you know We all want to populate the world But if you go talkin’ about good or bad Don’t you know that you can count me out Don’t you know it’s gonna be alright Alright, alright \* ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [October 8, 2015, 10:35pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/30 "2015-10-08T22:35:49Z")
One thing most people don’t appreciate is how slow evolution actually is. Let me give an example. Cystic fibrosis is a disease whose sufferers rarely reproduce. In white populations it can afflict as many as 1 in 2500 new births. It is, I believe, a non-self-linked recessive, meaning that both parents must carry the defective gene and only child in four will be affected (two will be carriers and one will not carry the trait). This means that one couple in 625 must both be carriers. Which means that 1 in 25 people are carriers (the odds that two carriers mate in the square of the odds of one being a carrier). Now think about that. One person in 25 in certain populations carry the gene, but the result is a loss of one part in 2500 of a reproductive agent. How long would it take to eliminate the gene? As for ginkgos, they are well-adapted for city life and that is an environment in which they prosper (and they could not have evolved for that environment). ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [October 8, 2015, 10:56pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/31 "2015-10-08T22:56:03Z")
You’re assuming that no couple ever has more than one CF-affected child, although your numbers match what’s actually observed; just a tiny little caveat there. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [October 9, 2015, 6:32am UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/32 "2015-10-09T06:32:08Z")
> [@dracoi](#): > > I’m still mad about algae and all that damn oxygen they dumped into the atmosphere. Don’t they know how many species they killed off? Evolution hasn’t been done right for the last billion years. > > But that’s all spilled milk. In the meantime, I’m setting up a “free the mitochondria” petition. Bloody typical. Mitochondria this, Mitochondria that. It’s cellular correctness gone mad I tell ya. Nobody every thinks about the Chloroplasts. ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [October 9, 2015, 12:24pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/33 "2015-10-09T12:24:17Z")
> [@Broomstick](#): > > How is a ginko “primitive”? > > For that matter, how is a bacteria “primitive”? > > Both species have had just as many years in which to evolve as we have. You can argue a human or ginko is _more complex_ than a bacteria, but they are no “more evolved”. > > And why do you say a ginko “deserves” extinction? They’re actually pretty darn hardy trees, which is one reason they survived long enough to meet up with humans that want to preserve them. They may not have changed much the last 50 or 100 million years, but that probably means they’re just a good pattern for a living organism. A Ginko is primitive because: -it has a very simple leaf structure -it reproduces with difficulty-it is difficult to propagate from seed -its fruit is not eaten by many animals, limiting seed dispersion That is why it was restricted to a very small range in China-while its more advanced competition (like the Norway maple) spread around the world. Until man came along, the Ginko was doomed to extinction. For some reason, Buddhist monks liked the tree, and dispersed it around China. later, westerners brought it to Europe, North and South America, and Australia…there are several in my neighborhood. So humans have saved the species…which was going to die out, according to the tenets of evolution. This was good for the ginko, but it was at the expnse of another tree species. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [October 9, 2015, 2:04pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/34 "2015-10-09T14:04:27Z")
For the most part, species that humans have saved from extinction are either in zoos, or are species that have found some niche to survive in somewhere in the human world. Let’s take cattle. Huge numbers of them worldwide; far more than would likely be around in the wild. This is because they’re domesticated- i.e. their best survival “strategy” as a species is to allow us to raise, kill and eat some proportion of them and their milk, because we also protect them from predators, make sure they’re fed and watered, and make sure they reproduce. This even extends to having us selectively breed them. Now if say… humanity were to vanish, cows would survive in drastically reduced numbers, and environmental pressures would cause them to end up fairly different in fairly short order. Witness the Longhorn breed; much of their signature characteristics derive from the feral cattle that they were bred from- traits more suited for the American Southwest than for feedlots and green pastures. And trees like gingkos are much the same way- something akin to domestication is going on- they look good and grow well in cities, so that’s their niche, and we propagate them. If somehow, human civilization were to go on for 50 million years, I’d wager that gingko trees will be very different- probably prettier, more pollution resistant, more likely to grow in suboptimal conditions, etc… because these will be the cultivars that will be planted. In a sense, mankind is taking the place of natural selection, but what does that matter? The same thing has happened with dogs, cats and dozens of other animal and plant species- if left to natural selection, they’d likely either evolve into something very similar to their original forms, or go extinct. ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [October 9, 2015, 2:56pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/35 "2015-10-09T14:56:01Z")
> [@ralph124c](#): > > But it seems that evolution gives rise to more complex forms of life. A Ginko tree is very primitive-if we “rescue” it from its (deserved) extinction, are we crowding out a more complex type of tree? By this kind of logic, sharks have been around way too long and should be laid off to make room for something more advanced. That’s not how nature works. ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [October 9, 2015, 3:45pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/36 "2015-10-09T15:45:57Z")
Natural evolution, the environment shaping us seemed to have lead to technological evolution, us shaping it. Either that will continue and we will become masters at it, or it will become unstable and fall apart, burn out, die out. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [October 9, 2015, 7:43pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/37 "2015-10-09T19:43:45Z")
> [@ralph124c](#): > > So humans have saved the species…which was going to die out, according to the tenets of evolution. This was good for the ginko, but it was at the expnse of another tree species. You’re still not even coming close to getting it. It _may_ have been in the process of dying out, because of _the environment in which it found itself_. There is NO SUCH THING as a “tenet of evolution”. Evolution doesn’t give the tiniest bit of a shit as to whether a species dies out or not. It certainly does not dictate who _should_ die out. The ginkgo was in an environment for which it was (perhaps) not terribly well-adapted. Then the environment was changed, and now it is doing better. No “rules” have been violated. No “should have” was thwarted. Evolution is just what happens. The end. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [October 9, 2015, 8:34pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/38 "2015-10-09T20:34:12Z")
Forgot to add that this: > [@](#): > > but it was at the expnse of another tree species. is nothing but PURE speculation. ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [October 10, 2015, 12:23pm UTC](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609/39 "2015-10-10T12:23:45Z")
> [@HMS\_Irruncible](#): > > By this kind of logic, sharks have been around way too long and should be laid off to make room for something more advanced. That’s not how nature works. But sharks (for all their archaic design-cartiliginous “bones”, small brains, etc.) are flourishing. Ginkos were not. Or an even better example-the wooloomooloo pine from Australia-restricted to ONE remote valley-that was not evolutionary success. [Previous page](https://boards.straightdope.com/t/when-humans-thwart-evolution-what-happens/733609.md?page=1)