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. Godzilla 214

    Godzilla 2142 soat oldin

    “Big deal what else can your tongue d- no…..” “Big deal how fast can ya flick I- nah”

  2. Katie Papp

    Katie Papp5 soat oldin

    why does the human tongue gross me out more than lizards and snakes.... or other animals?

  3. NeoGence

    NeoGenceKun oldin

    3:13 Send this part to someone with no context Reply with reactions

  4. A M

    A M3 kun oldin


  5. Charles Bronson

    Charles Bronson3 kun oldin

    Yet the human tongue lip thing at the end was the most disgusting. How is that? 🤔🤣

  6. Natasha S

    Natasha S3 kun oldin

    When humans do it it’s an HR violation 😹 I laughed way too hard at that

  7. kyle

    kyle3 kun oldin

    "When humans do this it's called a HR violation" had me dying

  8. Keith Mccrary

    Keith Mccrary4 kun oldin


  9. Brian Mulvaney

    Brian Mulvaney4 kun oldin

    That’s what he said 😂

  10. Phil Collins

    Phil Collins4 kun oldin

    No frogs?

  11. HAG

    HAG4 kun oldin

    My bearded dragon just got alot wierdery

  12. Roger Martinez

    Roger Martinez5 kun oldin

    I can’t watch these videos in public, almost spit out my drink twice from laughter. Great content, always brings a smile to my face.

  13. BGreen

    BGreen5 kun oldin

    I wish they made Blue Raspberry Jolly Ranchers. Favorite Slurpee !

  14. Mathew Neisen

    Mathew Neisen5 kun oldin

    This guy has spoiled all other nature documentaries for me, and I'm sorry but comedy central can suck it! Brain Witch 🤣 HR violation 🤣 ... so much comedy gold!

  15. Teh Chikon

    Teh Chikon6 kun oldin

    I need "snowman's baby-maker" on a coffee mug.

  16. Awkward

    Awkward7 kun oldin

    4:25 When Humans do this (sticks out tongue to mimic the slow motion) It's called an HR Violation (dies with laugher)

  17. Brad Pitt

    Brad Pitt7 kun oldin

    Haha brain witch!!

  18. Dave Williams

    Dave Williams7 kun oldin

    "Dr schwenk goes deep." "no jerry it's not a fetish" 0:40 ok this is epic. OMG i am in love with this channel

  19. The Dude

    The Dude8 kun oldin

    I was flicking my tongue up and down when he said HR violation 😭😭

  20. Tdotpescot

    Tdotpescot8 kun oldin

    When humans do this it’s called an HR violation… and I’m dead. 😂😂😂

  21. Pamela C

    Pamela C8 kun oldin

    So glad I wasnt taking a drink when ya said brain witches ....roflol I have never heard them called that. Gotta remember that one. Thanks

  22. Michael Budd

    Michael Budd9 kun oldin

    you flicked your tongue, didn't you

  23. GorbadIronclaw

    GorbadIronclaw9 kun oldin

    shout out to dr Schwenk!!

  24. kristobahl

    kristobahl9 kun oldin

    Dang that was all time, thanks zefrank! Shot at the end oh my god, humans are weird

  25. poonam Lekhram

    poonam Lekhram9 kun oldin

    What differencitae between snake and Lizard.. "Jerry it's not a snake... I know it's on it's Belly.. but it has legs" never goes from once memory

  26. Brenda Vega

    Brenda Vega9 kun oldin

    Lol!! I love it!

  27. Seven Simons

    Seven Simons9 kun oldin

    I love this guy lmao

  28. Alex Serdeliuc

    Alex Serdeliuc10 kun oldin

    Dr. Swhank interested in tongues...Aaaaaaanybody else?!? I am not reading all the comments to look for you sick perverts.

  29. Maniac_Mike

    Maniac_Mike10 kun oldin

    I got fired the second I did that LMFAO 😂😂 😂 it's an HR violation

  30. The Midnight Otaku

    The Midnight Otaku10 kun oldin

    Oh yeah it’s like when I use my tongue to suck in popcorn, even though that’s clearly not what it was meant for.

  31. Michelle

    Michelle10 kun oldin

    "Can't fool me, Brain Witch!; Prehistoric sex toy; When you do this, it's known as an HR violation; Not that, Jerry!..." The new viewers are subscribers - I am one!

  32. man with a username

    man with a username10 kun oldin

    4:50 "you know what you did

  33. Dee K. Asuncion

    Dee K. Asuncion10 kun oldin

    Funny how I'm now suddenly interested in things I never knew I was interested in before. . .😁😜😂

  34. The Ultimate Reductionist

    The Ultimate Reductionist10 kun oldin

    BUTT molecules in the.. sorry. But, molecules in the air...

  35. SHΔRΩΠ

    SHΔRΩΠ11 kun oldin

    Such a fantastic channel 👌👌👌

  36. Sabrina Rosario

    Sabrina Rosario11 kun oldin

    I never want to see that last video ever again.

  37. Ling Thompson

    Ling Thompson11 kun oldin

    butt molecules in the air

  38. MightyGoat5

    MightyGoat511 kun oldin

    ‘Brain witch’ 😂

  39. Tea Time Terrors

    Tea Time Terrors11 kun oldin

    Why are these so calming, yet so...SO hilarious?

  40. Croaker

    Croaker11 kun oldin

    The phrasiology of this guy is disgusting, no matter the subject

  41. eosofspades_

    eosofspades_11 kun oldin

    "Jerry, that's not a snake! ... I KNOW it's on its belly but it has LEGS, Jerry!"

  42. Chimdiie

    Chimdiie12 kun oldin

    He didn't talk about their PPs. My day is ruined.

  43. Jennifer Green

    Jennifer Green16 kun oldin

    Jerry - the worst/best editor on UZnick 😂😂😂 lol

  44. Christine Kovic

    Christine Kovic18 kun oldin

    There's nothing true or factual about this smutty evolution propaganda video. It used to be safe to let your young children watch an animal documentary, but this trash is not even fit for an adult! ):(

  45. Dan

    Dan18 kun oldin


  46. PsyMongazoid

    PsyMongazoid20 kun oldin

    Any decent biology teacher would play these videos to their class. Except nowadays it's probably a criminal offence because a parent somewhere would be OFFENDED.

  47. Foxfire0002

    Foxfire000226 kun oldin

    Found this channel via Nux Taku aka Nuxanor.... loving it!

  48. Brooklynyte

    BrooklynyteOy oldin

    Proper joke distribution is important. Schwenk knows a thing or two about a thing or two! A funny moment timeline..... Genius!

  49. Ferria

    FerriaOy oldin

    Oh so dam funny! LOL

  50. Evelyn Wildman

    Evelyn WildmanOy oldin

    “HR violation”😅😂🤣😂😅

  51. troberts1

    troberts1Oy oldin

    "Are the new viewers gone yet?" Love that throwback!

  52. Wes T

    Wes TOy oldin

    Butt molecules.

  53. rei rei

    rei reiOy oldin

    a snowmans WHAT

  54. mushy

    mushyOy oldin

    Humans smell with our tongues too. Ever notice some things taste the same as others smell? When air goes it nose it hits your tongue around your throat.

  55. Headless Harry

    Headless HarryOy oldin

    “A snow man’s bebe maker.”

  56. Harlan Quinn

    Harlan QuinnOy oldin

    Postage stamp from the 80s lol.

  57. Joshua Quinn

    Joshua QuinnOy oldin

    Omg 😂 addicted to this channel

  58. Communist Cat

    Communist CatOy oldin

    Oh Jerry you and your antics.

  59. Robin & Nick

    Robin & NickOy oldin

    I wonder if there even is a Jerry or if its all him lmao

  60. Broken Wench

    Broken WenchOy oldin

    Every time I see a snek flicking her or his tongue, I hear “Blelelelelele”.

  61. Lewcy

    LewcyOy oldin

    “Cant fool me brain-witch” 😂😂


    MOCOHO -JONNYOy oldin

    When humans do it it’s an HR violation😂😂😂😂

  63. Germie Napkins24

    Germie Napkins24Oy oldin

    .. he's a badass...sch'wah.. 🤣🤣🤣🤣

  64. lone wrecche

    lone wreccheOy oldin

    smarty nipple... god damn it, you started me coughing and laughing at the same time..... oO

  65. Eric Taylor

    Eric TaylorOy oldin

    I liked the slo-mo raspberry at the end.

  66. pandabear4565

    pandabear4565Oy oldin

    4:53 clever. Your a clever man

  67. Mary Julianne Tampol

    Mary Julianne TampolOy oldin

    I am not intelligent mom 2:52 *I'm a little smarty nipple*

  68. jmconnollyus

    jmconnollyusOy oldin

    This is just one of the finest zefrank vids/biology lessons ever. Just amazing.

  69. OPMoody

    OPMoodyOy oldin

    I love it when my tegu does his smell tongue wiggle, I want to know what he thinks about my smell

  70. Ken Plums

    Ken PlumsOy oldin

    Love you frank

  71. Jerry McDow

    Jerry McDowOy oldin

    He definitely looks at things a little different don't he 🤣

  72. MaxThaBaby

    MaxThaBaby2 oy oldin

    who needs eyes when you have a tongue

  73. Bored Artist

    Bored Artist2 oy oldin

    "When humans do it its called an HR violation." Me, with my tongue out, realizing I've been played.

  74. Polandjl

    Polandjl2 oy oldin

    Appreciated the callout for the old viewers :)

  75. ScarySara93

    ScarySara932 oy oldin

    Imagine if you were watching most of this video alone then at the very end during the credits; someone came into the room that you were in and saw that on the screen, you might have some explaining to do.

  76. V77710

    V777102 oy oldin

    Taking half a viagra got me so bad

  77. Trank

    Trank2 oy oldin

    8:31 *Bloubrlb* *Floop*

  78. Homeless Jedi

    Homeless Jedi2 oy oldin

    I might have actually enjoyed and paid attention in biology if this guy was my teacher

  79. ZarodGaming

    ZarodGaming2 oy oldin

    P A P I L L I

  80. Rafael .Padilla

    Rafael .Padilla2 oy oldin

    Calling psychologists “brain witches” is fantastic

  81. SamuelTheAdept

    SamuelTheAdept2 oy oldin

    The Hr violation joke made me die like that fish in the snakes mouth

  82. Echos

    Echos2 oy oldin

    Okay, wtf was that dude's tongue doing at the very end of the video? How did he do that? What WAS that??

  83. Asia Gethers

    Asia Gethers2 oy oldin

    The “wait sorry” everything he says butt something gets me everytime

  84. KP_SapphireMK2

    KP_SapphireMK28 kun oldin

    even ass

  85. Nazzu Arru

    Nazzu Arru2 oy oldin

    Exactly what my ex told my girlfriend.

  86. Eddie Garcia

    Eddie Garcia2 oy oldin

    Pure gold narration

  87. Insomania

    Insomania2 oy oldin

    “Brain witch” may be my new favorite quote of all time.

  88. Mel W.

    Mel W.2 oy oldin

    "Can't fool me brain witch!" 😂😂😂

  89. KaritKtana

    KaritKtana2 oy oldin

    I'm looking forward to the "Can't fool me, Brain Witch" t-shirt

  90. Rocky Journeys

    Rocky Journeys2 oy oldin

    the script was hilarious

  91. Kearstinne kenerson

    Kearstinne kenerson2 oy oldin

    just stumbled on to this channel but i think i am here for it.

  92. Rogue Gen

    Rogue Gen2 oy oldin

    5:56 I feel personally attacked

  93. Muhammed al Whosyourdadi

    Muhammed al Whosyourdadi2 oy oldin

    As always another amazing video.

  94. Upsidedown Nugget

    Upsidedown Nugget2 oy oldin

    “It’s always a demon with d**** horns. Can’t fool me brain witch.” Put that on a shirt please.

  95. Sheogorath the Daedric Prince of Madness

    Sheogorath the Daedric Prince of Madness2 oy oldin

    Still awesome! Seen every last one

  96. izzy jones

    izzy jones2 oy oldin

    I also love the whole concept and sound of the word "meniscus" and sticky liquid in general is super badass

  97. izzy jones

    izzy jones2 oy oldin

    I love ze Frank

  98. Derek Holcomb

    Derek Holcomb2 oy oldin

    Aren’t eyelids really just tongues dedicated to eyeball licking exclusively.

  99. ClawManV3

    ClawManV32 oy oldin

    9:49 This man not only studies reptile tongues to an extreme degree, but also analyzes the comedy in your videos to an extreme degree. He doesn't do anything by halves, does he?

  100. Xeno hari

    Xeno hari2 oy oldin

    the clip at the end is very disturbing and actually forced a cringe on my face lol

  101. Robson Matheus

    Robson Matheus2 oy oldin

    2:54 I think I would have a stroke trying to say this