3 ms·

>Yet, strangely, self-sacrifice exists in the natural world, even though it would seem to put individual organisms at an evolutionary disadvantage: The squirrel

>Yet, strangely, self-sacrifice exists in the natural world, even though it would seem to put individual organisms at an evolutionary disadvantage: The squirrel that lets out a cry to warn of a nearby predator is necessarily putting itself in danger. its obvious - just compare 2 species of squirrels, one which demonstrate behavior described above and another which doesn't. Which species would survive over time better? Without making complicated statistical calculations, the Nature has already calculated the answer - we have the squirrel species of the first kind, and not of the second. It is also obvious why selfishness still exists - because altruistic traits seriously decrease the survivability chances of the individual specimen carrying the traits.

hugh3 15y ago
Well no, because selection operates at the level of the individual, not the species. A "defector" mutant squirrel without the instinct to cry out when it sees a predator would have an advantage over the regular squirrel. Some folks have done those complicated statistical calculations, and I believe the current consensus is that group selection is a pretty minimal effect, except in exceptional circumstances. On the other hand, I'm not sure this is a great example. As a big scary potential predator I've scared away many a predator in my time, and y'know what? They don't cry out at all! They just run! Does anyone have experience with screaming squirrels?
- VladRussian 15y ago
  >Well no, because selection operates at the level of the individual, not the species. A "defector" mutant squirrel without the instinct to cry out when it sees a predator would have an advantage over the regular squirrel. Evolution is a statistical macro process aggregating individual selection events. Thus the "defector" mutant squirrel have higher chances to survive, yet the (sub)species consisting of only such "defector" squirrels will lose to the (sub)species where statistically significant share of specimen demonstrate altruistic behavior. People discussing evolution usually make 2 major mistakes : - assigning explicit "species evolution/survival" level motivation to specific action of specific specimen - directly extrapolating individual specimen events to the level of species, not paying attention to emergent higher-order system behavior >Some folks have done those complicated statistical calculations, such calculations is like law logic - can be bent both ways. Have any idea about chaotic dynamical systems and the effect even small perturbation can cause? >Does anyone have experience with screaming squirrels? if you hike in the SF Bay Area hills, you'll see the high social organization they exhibit, including "watch duty". Edit: for illustration, as somewhat related in principle - recently "Schneier on security" posted http://www.schneier.com/blog/archives/2011/05/status_report_t.html http://www.schneier.com/blog/archives/2011/05/status_report_... about "dishonest minority" - their individual situation is better, yet the species consisting entirely of the "dishonest minority" type specimen would obviously lose.
- olalonde 15y ago
  Do those models account for the fact that selfish individuals might get punished by the group? What if silent squirrels get systematically excluded from the screaming squirrels group? Wouldn't the loners have a lower life expectancy?

hugh3 15y ago

Well no, because selection operates at the level of the individual, not the species. A "defector" mutant squirrel without the instinct to cry out when it sees a predator would have an advantage over the regular squirrel. Some folks have done those complicated statistical calculations, and I believe the current consensus is that group selection is a pretty minimal effect, except in exceptional circumstances. On the other hand, I'm not sure this is a great example. As a big scary potential predator I've scared away many a predator in my time, and y'know what? They don't cry out at all! They just run! Does anyone have experience with screaming squirrels?

VladRussian 15y ago
>Well no, because selection operates at the level of the individual, not the species. A "defector" mutant squirrel without the instinct to cry out when it sees a predator would have an advantage over the regular squirrel. Evolution is a statistical macro process aggregating individual selection events. Thus the "defector" mutant squirrel have higher chances to survive, yet the (sub)species consisting of only such "defector" squirrels will lose to the (sub)species where statistically significant share of specimen demonstrate altruistic behavior. People discussing evolution usually make 2 major mistakes : - assigning explicit "species evolution/survival" level motivation to specific action of specific specimen - directly extrapolating individual specimen events to the level of species, not paying attention to emergent higher-order system behavior >Some folks have done those complicated statistical calculations, such calculations is like law logic - can be bent both ways. Have any idea about chaotic dynamical systems and the effect even small perturbation can cause? >Does anyone have experience with screaming squirrels? if you hike in the SF Bay Area hills, you'll see the high social organization they exhibit, including "watch duty". Edit: for illustration, as somewhat related in principle - recently "Schneier on security" posted http://www.schneier.com/blog/archives/2011/05/status_report_t.html http://www.schneier.com/blog/archives/2011/05/status_report_... about "dishonest minority" - their individual situation is better, yet the species consisting entirely of the "dishonest minority" type specimen would obviously lose.
olalonde 15y ago
Do those models account for the fact that selfish individuals might get punished by the group? What if silent squirrels get systematically excluded from the screaming squirrels group? Wouldn't the loners have a lower life expectancy?