Am I the only one who is annoyed by the guy clicking his pen the whole time?
It has ruined the whole thing for me. If he sat next to me in class, I would probably stab him in the neck with his pen. My cortisone levels are at a dangerous level.
Another point to consider with effect sizes and differences is the tendency we have to produce explanations before questioning significance. In this case the students did so at his urging, but it's worth bearing in mind that we all can get caught up in showing how clever we are rather than throwing out a cool explanation we thought of.
Professor Sapolsky has earned my respect in the way he examines claims (using the finding from different disciplines) concerning causality as applied to genes or environment. However, when it comes to inbreeding, his science goes out the window & he starts talking like an unquestioning believer. My experience with animal husbandry indicates two tails do not magically appear when closely related animals are bred. Random mutation still happens. Genetic drift still happens. Same evolution happens.
However, detrimental recessive traits within the genes of the organisms stand a greater chance of being expressed. Equally, the only way to find and remove detrimental recessives is by inbreeding.
Nevertheless, I am disappointed and befuddled that Professor Sapolsky did not apply his skeptical methodology to examine claims about reasons for what superficially appears as an inbreeding "aversion."
National Geographic once "saved" (?) a group of lions within a volcano crater from inbreeding.
@unseenstrings Continue inbreeding for many many generations and eventually something will show. It does help if there is a significant enough genetic fault that can manifest visibly to illustrate it. But a lot of problems go unnoticed even when they're obvious - German Shepard dogs for example, their back legs always go - that's from inbreeding. But there are also smaller ways things can go wrong that aren't necessarily so easy to see.
@ninjatoothpaste, continued inbreeding for many generations does not cause a detrimental trait to magical pop into existence. Random mutation and genetic drift are going to happen regardless of whether inbreeding is involved or not. A detrimental trait is more likely to be expressed via inbreeding. Likewise, and beneficial trait will more likely to be expression via inbreeding. Mice are inbred to make them genetically alike for cancer research. Australian sheep were inbred out of necessity.
Inbred organisms and organism that reproduce via asexual reproduction are going to have less genetic variation than sexually reproducing, non-inbred populations. And certain selective pressures--such as a viral disease--could wipe out a entire population when not enough genetic variation exists for some of the organism to be resistant to the disease. Of course, the resistant organism left to reproduce would inbreed to produce more resistant organisms. Evolution depends on inbreeding to a degree.
The genes of all dog breeds are "fixed" by inbreeding. The problems with the "back legs" on the German Shepard is the result of selecting out individuals with particular traits while failing to realize the dogs also had an unapparent trait that could cause hip and elbow dysplasia. Thus the problem with the "back legs" were more the result of bad selection than the process of inbreeding
If incest is a genetic aversion, laws against it are not required. Alliance Theory explains the incest taboo
@unseenstrings That's a very clear explanation and a point well made I think! In particular I liked your reference to Alliance Theory as I had never heard of that before, I'd thought of it but had no idea it was an actual theory. I'd imagine brothers and sisters who'd been separated would be much more likely to mate than unrelated siblings who'd grown up together - I'd say the selection is more for "group adherence behaviour" which gives rise to incest taboo rather than inbuilt repulsion.
@unseenstrings I was referring primarily to indiscriminate inbreeding; perhaps I'm a little behind on this but as I understand it the vast majority of mutations are neither particularly detrimental nor beneficial and second to those, the next most common mutations are detrimental followed by beneficial. Indiscriminate inbreeding results in more frequent expression of detrimental traits than of beneficial traits. Selective inbreeding allows more control over which traits are expressed.
@ninjatoothpaste P.S. Forgive my lack of clarity, I should have made the distinction more clear. I'm plenty aware that there is no magical appearance of two heads and a beard made of testicles as dictated by the divine law of commonly held misconception hehe :)
@ninjatoothpaste, natural selection occurs when some individuals are more prolific than others, and those that have more offspring differ genetically from those that have fewer. Sexual selection and selective breeding (by humans) can be thought of as special kinds of natural selection
When inbreeding results in more frequent expression of detrimental traits, whether or not those animals continue to exist and proliferate is determined by the selective process. Inbreeding is the quickest and...
...most effective way to find individuals with genetic defects and eliminate them from the gene pool. The problem with the "back legs" on the German Shepard is the result of selecting out individuals with particular traits while failing to realize the dogs also had an unapparent trait that could cause hip and elbow dysplasia. Of course, inbreeding is also the quickest and most effective way for breeders to find preferred genetic traits. Inbreeding is a handy tool in the hands of the professional
Oh, BTW, Professor Sapolsky mention that unrelated children reared together on Israeli Kibbutzim avoided one another as sexual partners. However, I don't believe he mention that out of 2516 marriages documented in Israel, 200 were between couples reared in the same kibbutz. Now his ignorance is forgivable, providing he doesn't teach such a lie to his students and points out that the incest taboo is too complex to be purely genetic.
Also, I mentioned Alliance Theory explains the incest taboo.
Fascinating!
Tamizushi 1 day ago
BEST PROFESSOR SO CALM ,HIS WAY OF SPEAKING HAS A BALMING EFFECT
SCORPIO99991 2 weeks ago
Wooo English grads! What a mistake I made.
PoledniceWP 4 weeks ago
I started to google this Chutes and Ladders study while he was talking. I feel like a fool.
mgalosi 1 month ago in playlist Course | Human Behavioral Biology
What a beard! I'm jealous. Can't wait till I get old enough to grow one...
Joobalooboo 1 month ago in playlist Behavioral Evolution - Stanford U
About 21:15 into it, when the camera monkey pans the audience, it looks like an ad for apple inc.
fudgesauce 2 months ago in playlist Course | Human Behavioral Biology 4
He changed his shirt!
troubledwatersofmind 3 months ago 5
Am I the only one who is annoyed by the guy clicking his pen the whole time?
It has ruined the whole thing for me. If he sat next to me in class, I would probably stab him in the neck with his pen. My cortisone levels are at a dangerous level.
freethinkerer 4 months ago 2
@freethinkerer i was happy w/ this vid till iread this.... lol : [
makemeupplez 3 months ago
Another point to consider with effect sizes and differences is the tendency we have to produce explanations before questioning significance. In this case the students did so at his urging, but it's worth bearing in mind that we all can get caught up in showing how clever we are rather than throwing out a cool explanation we thought of.
jonald32z 6 months ago in playlist Course | Human Behavioral Biology
Professor Sapolsky is so cool!!!
flybybutterflies 9 months ago 25
believe is mother imunitet agaist feedist ingreasse
Engravingsful 10 months ago
!!!
nuqleo 10 months ago
Professor Sapolsky has earned my respect in the way he examines claims (using the finding from different disciplines) concerning causality as applied to genes or environment. However, when it comes to inbreeding, his science goes out the window & he starts talking like an unquestioning believer. My experience with animal husbandry indicates two tails do not magically appear when closely related animals are bred. Random mutation still happens. Genetic drift still happens. Same evolution happens.
unseenstrings 1 year ago
However, detrimental recessive traits within the genes of the organisms stand a greater chance of being expressed. Equally, the only way to find and remove detrimental recessives is by inbreeding.
Nevertheless, I am disappointed and befuddled that Professor Sapolsky did not apply his skeptical methodology to examine claims about reasons for what superficially appears as an inbreeding "aversion."
National Geographic once "saved" (?) a group of lions within a volcano crater from inbreeding.
unseenstrings 1 year ago
@unseenstrings Continue inbreeding for many many generations and eventually something will show. It does help if there is a significant enough genetic fault that can manifest visibly to illustrate it. But a lot of problems go unnoticed even when they're obvious - German Shepard dogs for example, their back legs always go - that's from inbreeding. But there are also smaller ways things can go wrong that aren't necessarily so easy to see.
ninjatoothpaste 7 months ago
@ninjatoothpaste, continued inbreeding for many generations does not cause a detrimental trait to magical pop into existence. Random mutation and genetic drift are going to happen regardless of whether inbreeding is involved or not. A detrimental trait is more likely to be expressed via inbreeding. Likewise, and beneficial trait will more likely to be expression via inbreeding. Mice are inbred to make them genetically alike for cancer research. Australian sheep were inbred out of necessity.
unseenstrings 6 months ago
Inbred organisms and organism that reproduce via asexual reproduction are going to have less genetic variation than sexually reproducing, non-inbred populations. And certain selective pressures--such as a viral disease--could wipe out a entire population when not enough genetic variation exists for some of the organism to be resistant to the disease. Of course, the resistant organism left to reproduce would inbreed to produce more resistant organisms. Evolution depends on inbreeding to a degree.
unseenstrings 6 months ago
The genes of all dog breeds are "fixed" by inbreeding. The problems with the "back legs" on the German Shepard is the result of selecting out individuals with particular traits while failing to realize the dogs also had an unapparent trait that could cause hip and elbow dysplasia. Thus the problem with the "back legs" were more the result of bad selection than the process of inbreeding
If incest is a genetic aversion, laws against it are not required. Alliance Theory explains the incest taboo
unseenstrings 6 months ago
@unseenstrings That's a very clear explanation and a point well made I think! In particular I liked your reference to Alliance Theory as I had never heard of that before, I'd thought of it but had no idea it was an actual theory. I'd imagine brothers and sisters who'd been separated would be much more likely to mate than unrelated siblings who'd grown up together - I'd say the selection is more for "group adherence behaviour" which gives rise to incest taboo rather than inbuilt repulsion.
ninjatoothpaste 6 months ago
@unseenstrings I was referring primarily to indiscriminate inbreeding; perhaps I'm a little behind on this but as I understand it the vast majority of mutations are neither particularly detrimental nor beneficial and second to those, the next most common mutations are detrimental followed by beneficial. Indiscriminate inbreeding results in more frequent expression of detrimental traits than of beneficial traits. Selective inbreeding allows more control over which traits are expressed.
ninjatoothpaste 6 months ago
@ninjatoothpaste P.S. Forgive my lack of clarity, I should have made the distinction more clear. I'm plenty aware that there is no magical appearance of two heads and a beard made of testicles as dictated by the divine law of commonly held misconception hehe :)
ninjatoothpaste 6 months ago
@ninjatoothpaste, natural selection occurs when some individuals are more prolific than others, and those that have more offspring differ genetically from those that have fewer. Sexual selection and selective breeding (by humans) can be thought of as special kinds of natural selection
When inbreeding results in more frequent expression of detrimental traits, whether or not those animals continue to exist and proliferate is determined by the selective process. Inbreeding is the quickest and...
unseenstrings 6 months ago
...most effective way to find individuals with genetic defects and eliminate them from the gene pool. The problem with the "back legs" on the German Shepard is the result of selecting out individuals with particular traits while failing to realize the dogs also had an unapparent trait that could cause hip and elbow dysplasia. Of course, inbreeding is also the quickest and most effective way for breeders to find preferred genetic traits. Inbreeding is a handy tool in the hands of the professional
unseenstrings 6 months ago
Oh, BTW, Professor Sapolsky mention that unrelated children reared together on Israeli Kibbutzim avoided one another as sexual partners. However, I don't believe he mention that out of 2516 marriages documented in Israel, 200 were between couples reared in the same kibbutz. Now his ignorance is forgivable, providing he doesn't teach such a lie to his students and points out that the incest taboo is too complex to be purely genetic.
Also, I mentioned Alliance Theory explains the incest taboo.
unseenstrings 6 months ago
amazing talk :)
iurak6868 1 year ago 17