I worked as Matt Meselson's research asst. when he first came to Harvard, 1961 until 1965. He was a great person to work for/with. We used the density gradient technique for further phage genetics studies. The woman I worked for at Caltech, where my husband was an undergrad, Hildegarde Lamfrom suggested Dr. Meselson hire me, a we were going to Harvard too. He wanted someone willing to learn his careful techniques.
OMG, I learned this in high school. Absolutely beautiful and elegant experiment, and to see the real people behind this experiment brings so much emotion. Now as a cell biologist, revisiting this experiment on here just makes me so proud of being a part of this incredible field of biology. Someone has said to me "the most beautiful experiment is usually the simplest one of all" and this is an example.
At their time they thought they were graduate students and looked up to Richard Feynmann and Linus Pauling as great scientists. For students today they are the same for us.
I am grateful to know two of our most respected scientists who have confirmed the Watson-Crick model are still amongst us. Studying microbiology in this period of scientific development it’s hard to believe that the founding fathers of the DNA model are still alive, thank you for loving science and helping it grow. Stay healthy, and stay safe. Thank you 😊
Studied their experiment in 11th grade, and i remember how bad i too wanted to perform it by my self. Unfortunately couldn't do it at school level. Watching these guys today, surely made the experiment even more BEAUTIFUL for me.
This is so so so beautiful. Wish there was more content like this on the internet. The world is run by the scientists working day and night and not the celebrities dancing with the sharks. Scientists need more respect and exposure.
recall when a grad student and a professor (David Denison) told us a story about when he was a grad student at Caltech when they came into the grad student lounge with an autorad fresh from the experiment
I hope you could get to interview other known scientists/legends like them :) very nice interview.. it made me remember my super smart 75 year-old professor in my graduate studies :’)
Wow! Just wow. This is the most wonderful thing I've seen in a long time. Thank you for bringing these two together and having them share their work and friendship with us. This is a treasure.
Sir, you both are so adorable... Literally feeling on the top of the world cause of being able to learn your experiment by yourself. It not just the experiment it's also the history, scenario interest.. That ended up to the experiment and this is beyond textbooks truely fortunate..
On the eve of this Christmas evening, i was reading my Molecular biology book and just after finishing my sub unit , "Semi conservative mode of DNA replication " i opened TH-cam and this was the 1st recommendation video , Am so much fortunate that i am watching these two novel laureates . Respect from India 🤝🤝🤝
This type of video should be shown in schools and universities/colleges to encourage students to research. It feels like two grandpa telling the story of their youth.
These were the most beautiful 22 minutes. I really loved the video and do good to see them alive and talking about how they made it through and introduced the concept of semi-conservative replication to the world. So thankful to these men.
THIS SHIT WAS SO CUTE ITS MAKING STUDYING MOL BIO AND GENETICS WORTH IT. But I'm genuinely grateful for their work. It's the foundation of essentially everything I'm learning. I was initially planning on going for med school, but after seeing their work, I'm really interested in studying molecular biology and genetics further, and making my own (very small but still existant) contributions to that field.
You both are our inspiration ❤️ Never thought I would be able to hear this explanation directly from Meselson and Stahl .... Really I am lucky and grateful 💫🙌💝
I kinda hated these names because I didn’t get it and had to know the experiment for my next class test, but these guys are such wholesome grannies lol you can’t not like them
It's amazing how Professor Stahl hasn't changed much since I last saw him in 1996! Wish you well Frank and thank you for the opportunity of letting me work in your lab as an undergraduate- It was really a life-changing experience!
I am so lucky to have atleast watch them on TH-cam. I wish I can meet them in person. The talk was so enriching with humour, insights from those times and just the pure innocence of them. It made my day!!! Thank you iBiology for this great content. Can't thank you enough. ❤️❤️
I stumbled across this talk looking for inspiration for my own online teaching and saw your comment - hope you're well Jean! I still have one of your drawings on my office wall! Good memories of Eugene OR.
@@niabryant406 HI Nia! Nice to hear from you, in this roundabout way! I'm doing well, though sad we couldn't come visit the family, this summer..I was fortunate to have squeezed in a visit in February, before Covid hit, while they were filming this video. Hope you are doing well, too, and that you found some inspiration here for your work! If you are ever in Mexico, come visit us in Oaxaca!
Thank you so much iBiology for providing this amazing interview with two of my scientist heroes. When learning about semiconservative DNA replication, first at school and then again at university, I never thought I'd be able to see Meselson and Stahl in an interview.
Just wow...glad to listen to these 2 geniuses...they seem best buddies & so nostalgic remembering all that stuff...just observe their great sense of humour... it's delightful to see them explain all that in person... how beautifully presented...! Thanks 😇❤️ Please bring more such interesting scientific videos.
My day couldn't be any better than this, watching our legends alive, healthy and reminiscing their journey of experiment! 🤩 I feel so lucky to be a biology student!
WoW! I haven't been this surprised since seeing a talk from Dr. Watson on your channel! makes you think, most of what we know about biology is fairly recent.
I mean....Meselson, Stahl, Fynmann, Watson, Creek all these great people at a place....what an atmosphere must have been there...one can only imagine now.🔥❤️🙏
I was unaware that they're alive, it's such an honour to see you sir! Regards from me, big fan of your work! Thank you so much for this video. I'm very grateful to encounter this video.
Thank you so much for the video. We are Thankful their beautiful and lovely experiment. It's a very pleasant feeling to see them. May they live for a long...... .
Can someone please tell me how did they know exactly one generation of division/DNA replication had occurred? How do you distinguish two generations of replication from say one or three or more? Also, what do generations 0.7 or 1.9 mean? Thanks a lot!
Generation time of the specific bacterium bro! For example E.coli divides every 15 to 20 mins. Generation 0.7 means 10.5 mins and generation 1.9 means 28.5 mins for E.coli (assuming generation time to be 15 mins).
@@arunkumars6257 Thanks for your reply. My doubt mainly was, is the generation time information sufficient in this case/experiment. Because different bacteria will be in different stages of it's cycle and they are not synchronized. So, not all of them will divide after 15 minutes so we should end up with a smear on the density gradient picture, right?
@@SrinivashM29 I guess some optimisations before experimentation might solve this issue. Think of the lag phase all bacteria faces whenever they are exposed to new environment, that might synchronize their growth. Likewise heavy N and light N medium might work in synchronizing their growth.
I thought that they at least might have attempted to synchronize replication by culturing bacteria till stationary phase or at low temperature, but just realized that they hadn't done anything. Take a look at this www.ncbi.nlm.nih.gov/pmc/articles/PMC1307605/
@@volkanergin521 Thanks a lot for the link. It throws a lot of light into the actual experiment. From the link: 'Fragments that had a strand with a transition point from heavy to light and would thus have 'non-quantized' density would have been very rare (1 per 200) and thus not visible in the caesium chloride density gradient.' Can you please explain why these intermediate fragments would be very rare?
What a thoroughly enjoyable video! I had so much fun watching it. Biology is cool and it has always been cool. I am glad these guys were around to contribute to our collective understand of life.
@16:27, the dispersive model would predict that after two replication cycles, every strand of DNA should contain about 25% ¹⁵N and about 75% ¹⁴N. So that should be all the same weight
The intensity with which they felt the beauty of it all must have been so grand. Just hearing them talk about it is so overwhelming that I teared up. Probably because of how well they lend us their senses to be able to soak it all in through their expression.
Brilliant! 😄. I feel so fortunate to have found this video and the channel behind it. I have attempted to be a science communicator my whole life. I don't have all of the math, but I do have the intrinsic fascination with the nature of reality and our universe.... Thank you!
Atomic physics is a result of Darwinian evolution. Thats why Cellular Biology and Atomic Physics share the same theme Units comprised of a nucleus shrouded within a shell, and the capacity to bond with like units and build bodies. This depicts cellular biology just as readily as it depicts atomic physics. Do you need a bigger clue than this?
Why do people think that putting annoying music behind people talking about discoveries enhances the video. It just makes it harder to hear what they are talking about.
NEVER THOUGHT THEY’RE ALIVE
LOVE U GUYS
Wow..dont these guys look adorable. And the pic promises to be an entertaining talk
Couldn't have imagined to learn this experiment from them. Internet is surely a beautiful place.
I worked as Matt Meselson's research asst. when he first came to Harvard, 1961 until 1965. He was a great person to work for/with. We used the density gradient technique for further phage genetics studies. The woman I worked for at Caltech, where my husband was an undergrad, Hildegarde Lamfrom suggested Dr. Meselson hire me, a we were going to Harvard too. He wanted someone willing to learn his careful techniques.
How lucky!
This is amazing! What an enriching experience that must have been.
ava ropui ve
Could these 2 dudes identified an intermediate light/heavy DNA in a mis-sense mutant amt walkingbon a pair of false left handed walking legs in 1965?
I have just started my PhD, It feels amazing to see such great souls.
Same here brother! What is your project?
@Ankeet r u from india
@@purabiborah9590 yes, n u?
I m also from india... In where you are doing PhD
@@purabiborah9590 iisc Bangalore
Wow! Really interesting, only read about them in my Biology book, never thought would hear them speak!
OMG, I learned this in high school. Absolutely beautiful and elegant experiment, and to see the real people behind this experiment brings so much emotion. Now as a cell biologist, revisiting this experiment on here just makes me so proud of being a part of this incredible field of biology. Someone has said to me "the most beautiful experiment is usually the simplest one of all" and this is an example.
I love the way how this great experiment started a lifelong friendship 🧿
Cant believe such a great video is out here in youtube
thank you. we hope you check out some of our other films as well.
At their time they thought they were graduate students and looked up to Richard Feynmann and Linus Pauling as great scientists.
For students today they are the same for us.
I literally have goosebumps, i feel great that i chose to study biology. Love you guys..
wow .. this is intelligence how simply they explained everything with a flow . two gems of biology world, we all are blessed.
I am grateful to know two of our most respected scientists who have confirmed the Watson-Crick model are still amongst us. Studying microbiology in this period of scientific development it’s hard to believe that the founding fathers of the DNA model are still alive, thank you for loving science and helping it grow. Stay healthy, and stay safe. Thank you 😊
Studied their experiment in 11th grade, and i remember how bad i too wanted to perform it by my self. Unfortunately couldn't do it at school level. Watching these guys today, surely made the experiment even more BEAUTIFUL for me.
Fascinating interview! I am inspired by their genius, passion, and dedications. Thank you for putting this out.
This is so so so beautiful. Wish there was more content like this on the internet.
The world is run by the scientists working day and night and not the celebrities dancing with the sharks.
Scientists need more respect and exposure.
recall when a grad student and a professor (David Denison) told us a story about when he was a grad student at Caltech when they came into the grad student lounge with an autorad fresh from the experiment
I hope you could get to interview other known scientists/legends like them :) very nice interview.. it made me remember my super smart 75 year-old professor in my graduate studies :’)
Now thinking about it, learning biology indeed feels like the "puzzles" I used to do as a child.
What a beautiful telling of this story. Wonderful piece!!
The Most "Clear" Experiment.
can't believe this ,:i read about them in my biology book .God bless them..
Wow! Just wow. This is the most wonderful thing I've seen in a long time. Thank you for bringing these two together and having them share their work and friendship with us. This is a treasure.
I never knew that you can find how DNA replicates itself by sometimes sleeping in class. Now I have the courage to do smthng like this
We studied them in books at school. And now they are out there.
Talking!
That's interesting!!
Yes, i was shocked to find out that they made this interview
This is amazing!!! I have tears in my eye. Such a wonderful journey. Thank u so much for this video.
their friendship is so wholsome
Sir, you both are so adorable... Literally feeling on the top of the world cause of being able to learn your experiment by yourself. It not just the experiment it's also the history, scenario interest.. That ended up to the experiment and this is beyond textbooks truely fortunate..
On the eve of this Christmas evening, i was reading my Molecular biology book and just after finishing my sub unit , "Semi conservative mode of DNA replication " i opened TH-cam and this was the 1st recommendation video , Am so much fortunate that i am watching these two novel laureates . Respect from India 🤝🤝🤝
This type of video should be shown in schools and universities/colleges to encourage students to research. It feels like two grandpa telling the story of their youth.
These were the most beautiful 22 minutes. I really loved the video and do good to see them alive and talking about how they made it through and introduced the concept of semi-conservative replication to the world. So thankful to these men.
I wish I could stay at their house across the lab with those the smartest yet the most fun people!
Agreed!
thank you sooooo much....... this is a priceless gift for me...
THIS SHIT WAS SO CUTE ITS MAKING STUDYING MOL BIO AND GENETICS WORTH IT. But I'm genuinely grateful for their work. It's the foundation of essentially everything I'm learning. I was initially planning on going for med school, but after seeing their work, I'm really interested in studying molecular biology and genetics further, and making my own (very small but still existant) contributions to that field.
I teach these lovely gentlemen's discovery to students in a small town in the UK. They have no idea, but a class full of British kids know about them.
Wow, the rock stars!
You both are our inspiration ❤️ Never thought I would be able to hear this explanation directly from Meselson and Stahl .... Really I am lucky and grateful 💫🙌💝
I kinda hated these names because I didn’t get it and had to know the experiment for my next class test, but these guys are such wholesome grannies lol you can’t not like them
Its nice to see that scientists are not boring people. A very interesting duo.
Wait am I really looking at the Meselson and Stahl.
It's amazing how Professor Stahl hasn't changed much since I last saw him in 1996! Wish you well Frank and thank you for the opportunity of letting me work in your lab as an undergraduate- It was really a life-changing experience!
I am so lucky to have atleast watch them on TH-cam. I wish I can meet them in person. The talk was so enriching with humour, insights from those times and just the pure innocence of them. It made my day!!! Thank you iBiology for this great content. Can't thank you enough. ❤️❤️
Great talk, and beautifully edited! (AndI I love that the llamas made the cut!).
I stumbled across this talk looking for inspiration for my own online teaching and saw your comment - hope you're well Jean! I still have one of your drawings on my office wall! Good memories of Eugene OR.
@@niabryant406 HI Nia! Nice to hear from you, in this roundabout way! I'm doing well, though sad we couldn't come visit the family, this summer..I was fortunate to have squeezed in a visit in February, before Covid hit, while they were filming this video. Hope you are doing well, too, and that you found some inspiration here for your work! If you are ever in Mexico, come visit us in Oaxaca!
This was amazing...!.. To hear those who were actually behind these experiments speak about it is such a delightful experience!
We usually see black and white photos of scientists in text books! God already blessed us all to watch this most beautiful video! 😍😍
Great video!
This is beyond beautiful. Thank you all.
This is just amazing! Listening to these two geniuses is just great!
Thank you so much iBiology for providing this amazing interview with two of my scientist heroes.
When learning about semiconservative DNA replication, first at school and then again at university, I never thought I'd be able to see Meselson and Stahl in an interview.
What a pleasant experiment indeed. Truly inspiring.
What a beautiful interview.
Just wow...glad to listen to these 2 geniuses...they seem best buddies & so nostalgic remembering all that stuff...just observe their great sense of humour... it's delightful to see them explain all that in person... how beautifully presented...! Thanks 😇❤️ Please bring more such interesting scientific videos.
My day couldn't be any better than this, watching our legends alive, healthy and reminiscing their journey of experiment! 🤩 I feel so lucky to be a biology student!
They seems to remember every detail even at such a age🙏🙏🙏🙏
Would you please consider posting a full version of the interview? I would love to listen to all of the jokes and laughter! Thank you.
"The most beautiful persons in science"
when they started explaining, i got goosebumps .............for a genetics student it's like listening to god himself .OMG 😁😁😁
WoW! I haven't been this surprised since seeing a talk from Dr. Watson on your channel! makes you think, most of what we know about biology is fairly recent.
More beautiful than read from the books!
I mean....Meselson, Stahl, Fynmann, Watson, Creek all these great people at a place....what an atmosphere must have been there...one can only imagine now.🔥❤️🙏
These two gems of molecular biology are really so inspiring 🔥🔥🔥
I'm so thankful I came across this! What a great time to be alive! Much love to you fellows heart
I'm not much for this kind of science but they make it sound like so much fun! Dan Rather recommended it on Twitter so I had to check it out!
I am fascinated. Thank you for this great interview
What a lovely interview!
Thank you for you life times work much respect to you and all fellow sincere scientists 👨🔬👨🔬👨🔬👨🔬❤❤❤❤❤❤❤❤
I always see there pics in books and thesis , It nice to watch both of him in a live frame . World's most beautiful Experiment. ❤
It is a great chance to learn about their experiment directly from them!
I was unaware that they're alive, it's such an honour to see you sir! Regards from me, big fan of your work! Thank you so much for this video. I'm very grateful to encounter this video.
Omg!!! I'll be watching them live! Goosebumps
Thank you from the bottom of my heart ibiology. You just made my day!!
Thank you so much for the video.
We are Thankful their beautiful and lovely experiment.
It's a very pleasant feeling to see them.
May they live for a long...... .
So intelligent yet! Amazing conversation..they Sure are still with us!! Thank you for sharing!!
Can someone please tell me how did they know exactly one generation of division/DNA replication had occurred? How do you distinguish two generations of replication from say one or three or more? Also, what do generations 0.7 or 1.9 mean? Thanks a lot!
Generation time of the specific bacterium bro! For example E.coli divides every 15 to 20 mins. Generation 0.7 means 10.5 mins and generation 1.9 means 28.5 mins for E.coli (assuming generation time to be 15 mins).
@@arunkumars6257 Thanks for your reply. My doubt mainly was, is the generation time information sufficient in this case/experiment. Because different bacteria will be in different stages of it's cycle and they are not synchronized. So, not all of them will divide after 15 minutes so we should end up with a smear on the density gradient picture, right?
@@SrinivashM29 I guess some optimisations before experimentation might solve this issue. Think of the lag phase all bacteria faces whenever they are exposed to new environment, that might synchronize their growth. Likewise heavy N and light N medium might work in synchronizing their growth.
I thought that they at least might have attempted to synchronize replication by culturing bacteria till stationary phase or at low temperature, but just realized that they hadn't done anything. Take a look at this www.ncbi.nlm.nih.gov/pmc/articles/PMC1307605/
@@volkanergin521 Thanks a lot for the link. It throws a lot of light into the actual experiment.
From the link: 'Fragments that had a strand with a transition point from heavy to light and would thus have 'non-quantized' density would have been very rare (1 per 200) and thus not visible in the caesium chloride density gradient.'
Can you please explain why these intermediate fragments would be very rare?
Being a Biology student, I just love watching them and yeah it's awesome listening to them 😊
Like Watson&Crick these 2 guys, likeable they may be, thought they could become Gods and give mankind the keys to Creation. This is BLASPHEMY.
What a thoroughly enjoyable video! I had so much fun watching it. Biology is cool and it has always been cool. I am glad these guys were around to contribute to our collective understand of life.
Two Lovely Brilliant Men, Thank you for your contribution to science and biology and for a better understanding for our existence
This should be named 'The most beautiful Video'!! I am not able to comprehend Messelson, Stahl, Temin and Feynman in the same room!
When I read about them.. I thought they'll be serious looking grumpy ppl.. But damn they r hella cute❤
The results spoke themselves! 🤩
What a beauty!! This is how beautiful science looks!!
stumbled across this channel recently and I'm loving your content, thank you
Thanks a lot ibiology
It's really amazing to see and hear these words of legends..
Proud to be a geneticist
@16:27, the dispersive model would predict that after two replication cycles, every strand of DNA should contain about 25% ¹⁵N and about 75% ¹⁴N. So that should be all the same weight
The intensity with which they felt the beauty of it all must have been so grand. Just hearing them talk about it is so overwhelming that I teared up. Probably because of how well they lend us their senses to be able to soak it all in through their expression.
Great experience
29 Feb I gave biology exam ,I studied the experiment for exam
That's not only interesting. It is also fascinating how their way of life were mentioned. Their friendship is wholesome
Brilliant! 😄. I feel so fortunate to have found this video and the channel behind it. I have attempted to be a science communicator my whole life. I don't have all of the math, but I do have the intrinsic fascination with the nature of reality and our universe.... Thank you!
Atomic physics is a result of Darwinian evolution. Thats why Cellular Biology and Atomic Physics share the same theme
Units comprised of a nucleus shrouded within a shell, and the capacity to bond with like units and build bodies. This depicts cellular biology just as readily as it depicts atomic physics.
Do you need a bigger clue than this?
This interview is also beautiful! Thank you, really appreciate their passionate talk and iBiology team!
It so sweet to see these two intelligent men discussing about discoveries, memories...so sweet, inspiring as well...loved it. Thanks for sharing
You both are the reason to find the research so magical. Thanks for all your contributions to this world.
I am class 12 student found their experiment its just amazing and truly the most beautiful experiment
Why do people think that putting annoying music behind people talking about discoveries enhances the video. It just makes it harder to hear what they are talking about.
People say that I don't wear good clothes.
Now I'll say them there is a famous guy with same study as mine, and he don't wear pants for interview.
Welp...that's it.
Thanks for this beautiful video!
The most beautiful team! 😊