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Science and Magic From a Giant Amazon Treefrog

Skin secretions collected from the Waxy Monkey Treefrog (Phyllomedusa bicolor) are used by the Matsés Indians of Peru for ‘hunter magic’–the secretions are burned into skin of humans, resulting in vomiting, passing out, then waking a few hours later to ‘feel like a god,’ ready to hunt! These indigenous people of the Amazon ‘milk’ the frogs to collect a cocktail of peptide chemicals known as ‘sapo.’

Such nonlethal secretion collection can yield new insights into frog skin chemistry, for example, sugar was found this year in tropical poison frogs that had been studied for over 50 years by using a different approach to collect everything that oozes from skin glands. More recently, secretions collected specifically from the leg (tibial) glands of the Waxy Monkey Treefrog yielded additional peptides and encoding DNA not previously detected from glands on the head (the parotid glands). The difference in the peptides secreted from glands on the legs versus glands on the head may be to ‘deal with rearguard predators or may indicate that the tibial glands have arisen more recently in the evolution of the species and have yet to express the full spectrum of peptides from the parotids,’ said study co-author Professor Chris Shaw from the School of Pharmacy, Queen’s University in Belfast. These findings were published as ‘Molecular cloning of skin peptide precursor-encoding cDNAs from tibial gland secretion of the Giant Monkey Frog, Phyllomedusa bicolor (Hylidae, Anura)’ in the scientific journal Peptides.

One type of peptides from this group of frogs, the dermorphins, were recently exposed in the New York Times as being illegally used in horses so that they could race faster with no pain. Dermorphins are 40 times more powerful than the pain-killer morphine, and such components of ‘sapo’ contribute to the Matsés heightened senses and abilities to run quickly without pain, making them better hunters. In the gallery above, explore more about these frogs including secretion collection by our team and Matsés peoples from Peruvian Amazon rainforests. Learn more about forests from around the world via the Indigenous Forest Research Organization for Global Sustainability (i.F.r.o.g.s.).

Watch the Matsés collecting process below.

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  1. Marc Anthony
    July 5, 10:02 pm

    Do u realize there isn’t walmart where this gentleman lives princess? Before you go feeling sad for the frog

  2. Amazon Explorer
    Iquitos, Amazon rainforest, Peru
    April 7, 2016, 6:16 pm

    Hola people:

    We are from Amazon Explorer, we organize expeditions to the Matsés tribe. This is just to say that the indigenous shaman milk the frog and they release it unharmed. They just stress out the frog in order to the animal produce toxins.


    Hector Vezirian
    Amazon Explorer
    Iquitos, Amazon River, Peru (South America).

  3. Don Ivey
    Saratoga, Cal.
    March 18, 2013, 4:41 pm

    Ive heard this drug lets them “see”better for hunting, this looks cruel but I bet they release it unharmed, just stressed out.

  4. Mike Oregon
    December 31, 2012, 5:59 pm

    When are going to stop exploding animals? I cannot wait to see what big corporations are going to do with this new niche… Thanks, Mr. National Geographic for giving them new ideas…

  5. Nayan
    December 31, 2012, 1:48 pm


  6. Amosis
    December 31, 2012, 2:04 am

    I wonder how the tribesmen would like to be strung up like that.

  7. Douglas Argetta
    December 31, 2012, 12:33 am

    Sapo means frog in Spanish by the way

  8. Dan
    December 31, 2012, 12:24 am

    I’m curious as to why the plight of the frog, who is obviously being terrorized during this process, is entirely ignored.

  9. mahdi
    December 27, 2012, 5:42 am

    its som thing unbelivable