True Facts: Snake and Lizard Tongues

Dr. Kurt Schwenk
It was a pretty incredible gift to be able to work with Kurt on this episode. His work spans decades and it took multiple tries to understand it in a way that could be put together in a narrative. I am very grateful for all of his time, warmth and generosity. I had to leave many, many wonderful pieces of research and factoids out due to time constraints but I would urge any of you that are interested to dive deeper into his work.
His colleagues Dr. William G. Ryerson, Ms. Amanda E. Hewes and
Ms. Sara Horwitz contributed a great deal to some of the research that I mentioned.
Dr. Margaret Rubega ( deserves thanks for introducing me to Kurt in the first place.

Additional footage licensed from:
Envato Elements


  1. Jessica


    57 daqiqa oldin

    Dude, on the new Netflix show we are the champions Rainn Wilson talks EXACTLY like you, they should've let you do the series honestly, idk if it's just a coincidence or they 100 % make an effort to sound like you on purpose

  2. Christian Reyes Saenz

    Christian Reyes Saenz

    Soat oldin

    "When humans do this, it's called an hr violation" XD so true

  3. moss mother

    moss mother

    2 soat oldin

    Oh God the last clip I hate it

  4. demarek


    2 soat oldin

    One of your best - worth the wait :)

  5. byebye donnieboi

    byebye donnieboi

    2 soat oldin

    That slo-mo raspberry at the end made my day.

  6. Jessemonium


    2 soat oldin

    "Brian witches" is how I'll be referring to psychologists from now on

  7. James Ragsdale

    James Ragsdale

    3 soat oldin

    Yeah, and then you keep a bearded dragon as a pet and watch them repeatedly miss a superworm that they walked up to.

  8. Hanna G

    Hanna G

    3 soat oldin

    10:28 Oh no *I am uncomfortable*

  9. Taylor Doiron

    Taylor Doiron

    3 soat oldin

    Dr Shwenck is great.

  10. Nunyo-Bizznez


    4 soat oldin

    “Are the new viewers gone yet?” 😮😳🥺😭 Im flashing back, sports racers....

  11. Vukan Simic

    Vukan Simic

    4 soat oldin

    That iguanian have tongue like my ex, with all those absorbing papillae included

  12. Brandon Cummings

    Brandon Cummings

    4 soat oldin

    "Cant fool me brain witch." ......dead

  13. Samantha mother of cats

    Samantha mother of cats

    4 soat oldin

    That tongue clip at the very end made me uncomfortable...

  14. Gishathosaurus


    4 soat oldin

    "HR violation" lmao

  15. TheOrsencart


    5 soat oldin

    Educational and witty😁Love it, please keep making them. Xxx

  16. Sherlock'oTheTaco _

    Sherlock'oTheTaco _

    6 soat oldin

    Thank God you can make fun of yourself I love you

  17. PaperDoll Baby

    PaperDoll Baby

    6 soat oldin

    Lol the dude that's narrating is a boss, he's simply hilarious.

  18. whatsmyname _

    whatsmyname _

    6 soat oldin

    My dad found me watching this at 5 in the morning and I don't know how to explain what this is

  19. Egoletic


    6 soat oldin

    I'm sorry but WTF is this 10:20

  20. Joe Parker

    Joe Parker

    7 soat oldin

    So damn good, don't ever stop.

  21. vbddfy euuyt

    vbddfy euuyt

    10 soat oldin

    Jerry's script remains wild. "Jerry, that's not a snake." "No, Jerry, it's not a fetish. When a scientist does it it's an area of interest."

  22. Margarita Cricia Mei De Vera

    Margarita Cricia Mei De Vera

    10 soat oldin

    “Are the new viewers gone yet” AHAHAHAHAAHHA

  23. Chris F. Guerra

    Chris F. Guerra

    10 soat oldin

    "Are all the new viewers gone yet?" Nope. It seems like I've just started a journey.

  24. Rockin BoBokkin

    Rockin BoBokkin

    11 soat oldin

    Deep throating a squirrel butt. My week is complete.

    • vbddfy euuyt

      vbddfy euuyt

      10 soat oldin

      Love it! I would love a true facts video about giraffes! It be amazingly hilarious and educational!!

  25. abcdeisthekey PlayStation/PC

    abcdeisthekey PlayStation/PC

    11 soat oldin

    Gosh dangit Jerry. Get it together

  26. Justin Bailey

    Justin Bailey

    12 soat oldin

    I thought this episode was beautiful...until the credits lol. Whos that creep?

  27. Cyd Hansen

    Cyd Hansen

    12 soat oldin

    I absolutely need to know whose human tongue that was at the end. For research purposes. I'm a scientist, and dexterous human tongues are my "area of interest" 😏

  28. ReaverPrime


    13 soat oldin

    Is the puffin song your theme now? If its not, it should be.

  29. o--Kane101--o


    14 soat oldin

    So, have any non sex jokes?

  30. kristanmaree


    15 soat oldin

    Reptiles in black and white = *art*

  31. ጦርታር


    15 soat oldin

    Such a sensual ending there. Thanks for that image, ZeFrank.

  32. The Listener

    The Listener

    15 soat oldin

    great video lead-in for a "tongue & cheek" segment.... wait for it.. wait.......

  33. Linda - Beauty in Decay Explorations

    Linda - Beauty in Decay Explorations

    15 soat oldin

    New viewers vs old viewers: Ewe! vs Well that is normal for one of these videos. Lol

  34. Katrina H

    Katrina H

    15 soat oldin

    I don't know why this was in my recommends or why I clicked on it, but I definitely don't regret it.

  35. Melissa Watson

    Melissa Watson

    16 soat oldin

    That tongue thing at the end grossed me out.....

  36. Moses Bushido

    Moses Bushido

    16 soat oldin

    Should have been titled, "What Dat Mouf Do"

  37. Morgan Boutwell

    Morgan Boutwell

    16 soat oldin

    What an excellent video! GreaT job

  38. Sean Tomlinson

    Sean Tomlinson

    17 soat oldin

    Glorious. I'm excited for when I can share these videos with my sons. Currently 2 and nearly 6. Not for a while, clearly.

  39. Sam Z

    Sam Z

    17 soat oldin

    Love it! I would love a true facts video about giraffes! It be amazingly hilarious and educational!!

  40. Rachael Hires

    Rachael Hires

    19 soat oldin


  41. Ole Thomas Lindebø

    Ole Thomas Lindebø

    19 soat oldin

    Long awaited!

  42. marianna peresetsky

    marianna peresetsky

    20 soat oldin

    U sure make my day Zefrank!😜👍😝

  43. Patricc


    20 soat oldin

    Me: Just randomly strolling youtube's feed UZtop: Wanna see how amazing lizard's tongue is?

  44. Matthew Halo17

    Matthew Halo17

    20 soat oldin

    You mean a snake? No I mean a wurm lizard Snake No what are you not getting I’m talking about a wurm lizard A snake? Wurm lizard Say snake Snake Now what is a snake Not a wurm lizard ffffffFFFFFFFFFFFFFF

  45. Peggy Courtright

    Peggy Courtright

    21 soat oldin

    How can anyone hit dislike? 😆

  46. Amanda Geyer

    Amanda Geyer

    21 soat oldin

    I know better than to try and eat or drink anything while watching zefrank1 videos. THIS COMMENT SECTION has taught me to not attempt to consume anything while perusing the comments.

  47. So Interesting

    So Interesting

    21 soat oldin


  48. Brolly5


    23 soat oldin

    "I'll give an arm and a leg to be the best at it" This is god tier writing.

  49. lone wolfy

    lone wolfy

    23 soat oldin

    Stay to the very end... It's worth every second 🤣🤣😂

  50. Leah Kirk

    Leah Kirk

    23 soat oldin

    I utterly hated the credits. Must have reminded a dozen times to read them because I had to avert my eyes!

  51. azz. z

    azz. z

    23 soat oldin

    No true facts about dolphin? How could that be? Always knew those dodgy mammals are up to something.

  52. L.D Vlogs x

    L.D Vlogs x

    23 soat oldin

    ayyy teddy operation guy

  53. Mellie


    Kun oldin

    "when humans do it it's an HR violation" 😂😅🤣

  54. Harald Bob

    Harald Bob

    Kun oldin

    Actually its xeno tongues that'll blow your mind

  55. mash my pancakes

    mash my pancakes

    Kun oldin

    *Now teddy is on drugs*

  56. Sibler Inkognito

    Sibler Inkognito

    Kun oldin

    Sorry the evolution theory is outdated. There are no skelets found which leads to an evolution there is no APE/HUMAN there are apes skeletons and human skeltons but nothin in between. There are no skeletons/ fosils eather who show us that this creature was a preevolution before somthin other. Proof me wrong appreciated Much love 1 family

    • Sibler Inkognito

      Sibler Inkognito

      8 soat oldin

      @『Kageyama』 where?

    • 『Kageyama』


      Kun oldin

      There are...

  57. MsFlyingSnake


    Kun oldin

    Can’t fool me, Brain Witch! Roflmao

  58. deistmuttz


    Kun oldin

    Ending is so disturbing.. lol.. my favorite is like taking half of viagra.. LOL

  59. Nick's Cartoons

    Nick's Cartoons

    Kun oldin

    just found out that herpetology is a thing... I now know what I want to go to college for.

  60. Tg da boss 88

    Tg da boss 88

    Kun oldin

    RIP 699K views

  61. adrian.jpg


    Kun oldin

    “when humans do this, it’s called an HR violation” made me laugh so hard

  62. Indicteronomy


    Kun oldin

    This one is a gem. Thank you, zefrank, you bring joy to my life.

  63. Japheth Belgira

    Japheth Belgira

    Kun oldin

    Wishing there's a "HAHA" button on UZtop 🤣🤣🤣

  64. theplanetdestroyer


    Kun oldin

    Zefrank1's videos are so good i wanted to give everyone a like but there's 3000 of you, i think i managed seventy-something though..

  65. theplanetdestroyer


    Kun oldin

    What dat tongue do?

  66. AX-59


    Kun oldin

    Hey Zefrank, why not do a video on platypus? Did you?

  67. Samuel Peinado

    Samuel Peinado

    Kun oldin

    "...HR violation." LOL!

  68. Reimie Nijimura

    Reimie Nijimura

    Kun oldin

    True Facts about the Man o War pleeeaseeeeee...

  69. ThatDarnKitteh


    Kun oldin


  70. Kristie LT

    Kristie LT

    Kun oldin

    The human tongue at the end was the most disturbing thing I've seen in quite a while.

  71. Jayinder Kaushik

    Jayinder Kaushik

    Kun oldin

    Guy says babies like a sexual predator. Beybeys.

  72. johny VDS

    johny VDS

    Kun oldin

    i fricking love your content man, always making me smile while learning a thing or two 💗💗

  73. rupsha ghosh

    rupsha ghosh

    Kun oldin

    I've encountered the video on 69k likes. NICE

  74. Marianne Paulk

    Marianne Paulk

    Kun oldin

    If my teachers had had your sense of humor and delivery, I might be a frickin genius .

  75. Hus 9

    Hus 9

    Kun oldin

    Explosion of tung

  76. Haha-Aaa101


    Kun oldin

    amazing as always !

  77. sehhi vooty

    sehhi vooty

    Kun oldin

    “Snake rave.” “Think sinus infection, but in your mouth... Are the new viewers gone yet?” I love it XD

  78. Storm Nasca

    Storm Nasca

    Kun oldin


  79. Belgarath S.

    Belgarath S.

    Kun oldin

    “It looks like one of those inkblots that the brain witches make you look at “! Oh my God! Please stop being so damn clever!

  80. Storm Nasca

    Storm Nasca

    Kun oldin

    "I'll give an arm and a leg..." XD

    • Magellanic


      Kun oldin

      "the snake said 'i'll give an arm and a leg' and that's where the negotiations started"

    • sehhi vooty

      sehhi vooty

      Kun oldin

      "Brain witch," pft.

  81. Matty Matt

    Matty Matt

    Kun oldin

    I love how this sh!t is so funny while educational! It's like a Snake tongue... well balanced!

  82. Linh Nguyễn

    Linh Nguyễn

    Kun oldin

    im educated and entertained at the same time, great channel !

  83. Pyro Thermite

    Pyro Thermite

    Kun oldin

    Dr. Shwank is such a badass

  84. Clemens Gleich

    Clemens Gleich

    Kun oldin

    Wait for the end for some extra ... tongue.

  85. simon eric

    simon eric

    Kun oldin

    Was hoping the Jacobson’s organ would be mentioned in this video..

  86. Timothy Greer

    Timothy Greer

    Kun oldin

    You got all sciencey and stuff then BLAM the end made me forget everything I just learned

  87. Kelvin Neil

    Kelvin Neil

    Kun oldin

    Despite all the jokes, it's still give us education 👍

  88. eioshen boboi

    eioshen boboi

    Kun oldin

    Psychologist: will you please stop calling me a brain witch? I’m a doctor Me: what ever brain witch just make me not sad anymore

  89. Akira Gurung

    Akira Gurung

    Kun oldin

    He's back! HE'S BACK! Frank we missed you.

  90. Natalie Peters

    Natalie Peters

    Kun oldin

    I need to know what kind of snake that red and black one with the red eyes was wow 😍😍🐍

  91. MrPooPooJohn


    Kun oldin

    Life's the same, I'm smelling in stereo Life's the same, except for my tongue Life's the same, snakin' like vomero Life's the same, it'ssss all inside you...

    • eioshen boboi

      eioshen boboi

      Kun oldin

      Roflmao shag carpet of doom!!! Lol

  92. Pedro Abilleira

    Pedro Abilleira

    Kun oldin


  93. Quant Quill

    Quant Quill

    Kun oldin

    I would have liked anyway, but I clicked pretty fast at "shag carpet of doom".

  94. Tim Billings

    Tim Billings

    Kun oldin


  95. lmcgiglez


    Kun oldin

    "Brain witch," pft.

  96. John Christopher Oliver

    John Christopher Oliver

    Kun oldin

    "Stone aged sex toy" wait, what?! 🤣

  97. Ror Allen

    Ror Allen

    Kun oldin

    Please keep making vids. It makes my life suck less.

  98. Brent King

    Brent King

    Kun oldin

    I can see Franks videos in school LOL

  99. Dennis Cuesta

    Dennis Cuesta

    Kun oldin

    **confused learning**

  100. leminjapan


    Kun oldin

    "Evolution was like, 'Oh yeah, there's time.'" **chefs kiss** Masterpiece.