[HN Gopher] Evolution: Fast or slow? Lizards help resolve a paradox
___________________________________________________________________
Evolution: Fast or slow? Lizards help resolve a paradox
Author : rbanffy
Score : 46 points
Date : 2024-02-12 17:48 UTC (5 hours ago)
(HTM) web link (www.quantamagazine.org)
(TXT) w3m dump (www.quantamagazine.org)
| kingkawn wrote:
| Seems akin to a tall building being more durable if it can flex a
| little in the wind.
| Terr_ wrote:
| I find myself thinking of dog breeds: Over the last ~150 years,
| selective breeding has led to an explosion of phenotypes, but
| there's a limit to how much humans can take credit--or perhaps
| _blame_ --for all the results.
|
| Much of what we've done is to evoke particular _blends and
| combinations_ of a great many individual genes that already
| existed throughout in the species.
|
| _P.S.:_ IANADogGeneticist so these numbers are totally made-up,
| but imagine an island population of 1,000 "average dogs" or
| mutts that look the same. They collectively bear 20 distinct
| genes that promote Long Noses, and 15 distinct genes that promote
| Short Noses, and due to what chromosomes they're on, each dog
| might have a random ~4 from the Long Nose set and ~3 from the
| Short Nose set. On average you'll keep getting similar looking
| individuals, until some sinister aliens arrive and begin... _The
| Pug Project_ , leading to a bunch of poor lapdogs with 8-10 Short
| Nose genes and 0-1 Long Nose ones.
| ericmcer wrote:
| Selective breeding has some huge and obvious morality issues
| around it, but it is fun to think about possibilities. Hyper
| intelligent dogs? 10 foot tall humans?
| rollcat wrote:
| Did you read "Dune"? Basically the entire plot.
| chmod775 wrote:
| > I find myself thinking of dog breeds: Over the last ~150
| years, selective breeding has led to an explosion of
| phenotypes, but there's a limit to how much humans can take
| credit--or perhaps blame---for all the results.
|
| Dogs as a species wouldn't _exist_ if humans didn 't
| selectively breed a now extinct lineage of wolves, which to me
| means that humanity is to blame for all of it.
| strangattractor wrote:
| After reading the article it sounds absurd when you first think
| about it but leaves you with how else could it possible work
| after seeing the evidence.
|
| I am no evolutionary biologist but one might look at rapid
| adaptation as an evolutionary strategy in itself. I have always
| felt humans did this by using intelligence. Does anyone know of
| other mammals that can live in such a large range of environments
| without physically adapting?
| t-3 wrote:
| Humans _have_ physically adapted though. Skin and eye color,
| subcutaneous fat, underwater vision, high-altitude adaptations,
| resting body temperature, nose shape and nostril size, etc. We
| just haven 't had populations separated long enough to be
| unable to breed or be considered separate species.
| btilly wrote:
| Two notes.
|
| The first is for fun. See the miniature lasso that he used? It is
| easy to tie one out of a long blade of grass and catch lizards
| that way. The trick is that they've been adapted to ignore grass
| as a non-threat. So when they're about to be captured by a piece
| of grass, they literally can't see the grass. You have to remain
| far enough away, but you can bonk the lizard on the nose, pull
| your grass back, readjust and try, try again until you get it.
| It's a great trick to show kids!
|
| The second is that no mechanism is needed to revert a temporarily
| selected trait. Francis Galton was the first to document
| regression to the mean in inheritance. The child of two tall
| parents tends to be not as tall. The child of two short parents
| tend to be not as short.
|
| The reason this happens is that the recessives that influence the
| one parent's trait are often different from the recessives for
| the other parent. Therefore the child winds up expressing fewer
| recessives than either parent.
|
| What this means is that if you select for a given complex trait
| in a given generation, those who survive will have that trait.
| But unless you also select for it in the next generation, the
| population will mostly revert back on its own. It is only regular
| selection, sustained over time, which causes the selected for
| trait to breed true.
| pests wrote:
| This plays slightly into the slow climate change vs fast
| climate change issue. If climate changes slowly enough, this
| allows enough generations to build up the new traits needed for
| survival. Too fast, nothing lasts to evolve at all.
| Terr_ wrote:
| That makes me think of how--IIRC--amphibian genomes contain
| coding for a lot of different proteins that have about the
| same function but are stable/effective at different
| temperatures, especially during early development in the egg.
| (In contrast, mammals invest in genes that ensure the egg's
| external temperature is reliable.)
|
| (See also: Orthologous proteins, Heat shock proteins.)
| williamdclt wrote:
| > It's a great trick to show kids!
|
| Kids are cruel :( showing them how to hunt lizards is likely to
| lead to their torture and/or death
| throwup238 wrote:
| The trick is to make them eat anything they kill.
|
| "You kill it, you eat it!"
|
| That'll work the cruelty right out of them and set them up
| for a promising life post nuclear apocalypse. Lizards will
| bioaccumulate less fallout from the food chain than larger
| animals so they'll be a safer source of protein.
| mathgradthrow wrote:
| why would smaller animals accumulate less fallout?
| wizardwes wrote:
| It's more location in the good chain than size, and
| volume of food eaten vs body volume
| PH95VuimJjqBqy wrote:
| Me and my brothers hunted horned toads for years without ever
| killing any of them. I don't exactly think we were special
| either.
| girvo wrote:
| Depends how the kids are raised I guess. My brothers and I
| never tortured and killed any of the skinks we'd catch as
| kids
| andrewflnr wrote:
| I'm with Hendry, the guy who said the paradox is an illusion. I
| figured it was rapid change within a stable envelope within a few
| sentences of starting the article, but I waited for the other
| shoe to drop, because there must be something trickier if people
| have spent so much time on it ... It turns out the other shoe is
| "but now we have data about the details". Which is good, but
| nowhere near as dramatic as they make it out to be. You can see
| the outline of the solution just by thinking about the question
| for a second.
___________________________________________________________________
(page generated 2024-02-12 23:00 UTC)