ANTENNAS detect the presence of the enemy

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We found (and yelled at) a crazy tentacled caterpillar

On my recent travels through the Peruvian Amazon, I came upon the craziest caterpillar that I have ever seen and subsequently yelled at it for hours.  Why did I yell at it? Well, its strange behavior towards sound was why I noticed it in the first place. I had just climbed to the top of a canopy tower overlooking the rainforest when I called to my group below me – suddenly a flash of movement at eye-level caught my attention.

Hear about my caterpillar adventures below. And to check out more otherworldly jungle creatures — and even help with scientific discovery — join in our Wired Amazon project!

 

On a nearby tree branch hung a caterpillar with four strange tentacle-like appendages protruding from its abdomen. I might never have noticed this small brown insect had it not been for its unusual movement: noises would cause it to fire its tentacles in randomized directions, then slowly twirl back into a spring-like “ready” position to await its next alarm. This reaction to noise was so peculiar that once my group joined me around the creature, we proceeded to take turns yelling at it and filming its contorting reactions for over an hour.

After a little research, I found that this caterpillar is in the moth family Geometridae and is in the genus Nematocampa. Also referred to as ‘horned-spanworms’ or ‘filament bearers’, these peculiar caterpillars can be found in North America and the Neotropics. 

horned-spanworms

 

David Wagner, in his field guide ‘Caterpillars of Eastern North America,’ notes: 

“It is difficult to imagine what the [Nematocampa] larva is mimicking, but the overall effect is not unlike a fallen brown flower with exerted stamens. Alarmed caterpillars shunt hemolymph into filaments, enlarging them by as much as twice their resting length.” [1]


What Wagner seems to be proposing is that the larva movement is similar to the way flowers or other plant matter move in the wind: the behavior more effectively blends the caterpillar into its surroundings.

 Other potential purposes this behavior may serve to include:

  1. The tentacles extend when the caterpillar is alarmed so that an attacking predator (such as a bird) has a higher probability of snagging a tentacle, as opposed to the main body, so that the caterpillar may drop away and escape with its life (similar to how some lizards are able to lose their tails). 
  2. The setae, or “hairs,” located at the tip of a long tentacle could be highly sensitive vibration detectors that are able to sense predacious birds or insects that make nearby sounds [2].

Bizarre Caterpillar With Erupting Tentacles

What do you think? Screaming at caterpillars doesn’t fall into most people’s job descriptions. But that’s exactly what I found myself doing a couple of weeks ago in the Peruvian Amazon, all to bring the story of this bizarre organism to you! Leave a comment below and let us know how you feel about this peculiar caterpillar found in Tambopata, Peru.

To discover these fascinating caterpillars, along with dozens of other incredible species, book your dream trip to the Amazon today!

 

By Aaron Pomerantz, Entomologist 

You can follow me on Twitter @AaronPomerantz

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I can not say enough good things about my time at the Tambopata Research Center. Between the guides, the boat drivers, the chefs, the staff, the bartenders, the researchers, etc. Everyone was absolutely wonderful! If you are interested in viewing wildlife in the Amazon, this is the place for you! A special thank you to the maître d' Carlos who was so incredibly kind and hospitable and our guide Dino who was like a real life Indiana Jones. I can't wait to come back! Read all

An unforgettable, fully immersive jungle experience. Amazing how Tambopata Lodge delivers luxury touches in such a remote and rugged location. The food is fantastic, the staff incredible, and the wildlife sightings non-stop. The personalised itinerary and one-on-one guiding made the trip truly special—huge thanks to our guide Johan for sharing his passion and knowledge. The Macaw Project is inspiring, and it’s clear the lodge fully supports this important conservation work. Manager Brian was always kind, helpful. Well-done all involved. Read all

The most important fact we are grateful for is the true sense of understanding of the ecology of the Amazon the staff at Rainforest Expeditions (RFE) have shown us. RFE stands out for its stand against the pure, profit-motive initiatives many other tour operators do. We are very grateful to have had Carlos as our guide. Carlos is deeply dedicated, and is able to explain the nuances of the flora and fauna. The world today needs to act as one against the impact of climate change. RFE is one, bright shining light in this regard. Read all

We had a fabulous trip! The people were amazing, kind and very professional. The food was exceptionally good! The facilities are beautiful and well kept. We just loved our second time with Rainforest Expeditions and can't wait to go again!! Read all

Fantastic to be deep in the forest surrounded by incredible wildlife with our amazing guide Juan Carlos Yatto, who really knew his stuff! Also his photography skills meant that we could share our experience even better through his telescope using our phone cameras! We learned so much!! He went to extra lengths to find butterflies and moths for us along with so many different birds and monkeys. This was a travel highlight for us as experienced wildlife travellers. We loved our spacious room with no windows and open to more wildlife visitors but after 5 nights the bed could have been a little more comfortable. Luckily we had a second bed to use. Otherwise it was fantastic with hot water showers and fresh drinking water all the time. We were amazed at the variety of food on offer for breakfast, lunch and dinner and couldn’t believe they could have such a wonderful food offering in such a remote location. Even the wine and cocktails were great. I highly recommend spending the extra money and time getting to this location. We stayed at another lodge later which was closer to Puerto Maldonado and there was far less wildlife. Read all

Ederson made the stay at the lodge amazing. I have had many guides around the world and Ederson may be the best I have had across 50 countries. The lodge itself is nice, and has electricity. Food is good, and you really feel immersed in the amazon staying there. Its great that a portion of the money goes back to conservation and research. Noteworthy details: Ederson, the "commander" is the best guide! Read all

Through a travel agency in Lima we booked a 4day/3-night stay at Refugio Amazonas. We were looking for a lodge that was far away from Puerto Maldonado but didn't require almost a day to get there (like TRC), with extensive walking trails and with the principal jungle highlights nearby. We were not disappointed. As we later learned, this is probably the best lodge in the region! Well run, quiet, excellent food, beautifully located in the middle of the forest, everything was "right". Surprisingly there were few mosquitos or bugs. Emperatriz (MP as some call her), our guide, has a keen eye and took us on some unforgettable walks and boat rides, both day and night. The birds at the clay lick were fantastic. The lodge also had evening lectures by young researchers as well as special activities such as collecting night moths and setting a trap camera. We later received videos and photo's of what was found (including a puma!). I can recommend this lodge without reservation. Read all

Abbiamo scelto il Tambopata Research Center perché il nostro obbiettivo era di poter vedere le are da vicino. Ci siamo stati ad inizio dicembre scorso, l'inizio della stagione delle piogge, perciò abbiamo scelto di restare 5 notti/6 giorni, abbiamo messo in conto di perdere delle giornate a causa della pioggia e per la lontananza da Puerto Maldonado, per nostra fortuna durante il nostro soggiorno ha piovuto solo il giorno di partenza proprio quando arrivavamo in aeroporto. Non c'é stato un giorno che non ne abbiamo visto: are di diverse specie e colori e molti altri uccelli e primati, spettacolare l'incontro a pochi centimetri con un formichiere bianco, ma non il giaguaro. Consigliamo di pernottatre almeno 3 notti, il viaggio é molto lungo. Noi eravamo all'aeroporto di Lima già alle 8:00 di mattina e tra un volo in ritardo, uno spostamento in bus di ca. 45 minuti per arrivare al fiume, ed un trasferimento in barca veloce, siamo arrivati al lodge verso le 16:30. All'aeroporto ci ha accolto la nostra guida privata Alfred, che ci ha seguito per tutto il soggiorno, di giorno in giorno abbiamo deciso le escursioni da fare, ed Alfred si é rivelato essere una super guida, un occhio di falco per scoprire anche il più piccolo uccellino, con pazienza é riuscito a farci camminare chilometri nella giungla, ci ha spiegato molto sulla flora e fauna. Bravissimo a far video e foto con i nostri telefoni col suo binocolo e cavalletto che si portava sempre appresso, queste foto sono dei magnifici ricordi. TRC non é un hotel, é un centro di ricerca per le are, in mezzo ad una foresta ed a ore dal primo centro abitato, perciò non avevamo delle grandi aspettative ne sul cibo ne sull'alloggio Read all

This place is a treat!! Incredible flora & fauna, food and service - the staff is quite attentive. Interesting research, with lots of potential. Visiting the Peruvian Amazon Rainforest is a must do! Read all

We had the most amazing time EVER at Refugio Amazonas, and I am so very glad I booked our stay here. Honestly, this is to date probably the best travel experience we have ever had and I will never forget our time in the Amazon here. First of all, the lodge is beautiful. Our room was lovely. The beds were comfy. The bathrooms are large. It is incredible waking up to the sounds of the jungle and falling asleep to the insects at night. We did have some insects in our room, and a rodent, and even a tarantula (non poisonous)! But it was part of the experience. The food was great and they prioritize native and local ingredients. My partner and I are both vegan and they took SUCH good care of us. The food was delicious, and we had ample vegan options every meal. Everything from the first email contacts with Katia to the transfers to the first night info session to the activities-- which I will get to in a second-- was incredible. It is a bit pricey, but everything is included and there is nothing you need to worry about, and it was so worth it. OK now for the best part-- the activities. Holy wow. First of all, we had the best guide EVER-- Juan Carlos. He was amazing. He is a bird expert, knows so much about the animals who live in the rainforest, the insects, the trees, the plant life, it was incredible. He also so clearly cared that everyone in our group had an amazing time. He took so many pictures for us, pointed out so many animals for us, and made sure we all enjoyed every moment. I can’t thank him enough because it made our time here so very special. We went on many activities that were amazing, and we saw so many animals— capybaras, howler monkeys, capuchin monkeys, so many incredible insects, frogs, tarantulas, so many many birds and butterflies. Every activity was amazing but the highlights were the macaw clay lick and the canopy tower. And we were super impressed and happy to hear about their commitment to conservation, protecting the animals, and supporting the native community nearby. There is so much I could say about our stay here but I would recommend a 3 night stay over 2 nights (so you can do more activities), and make sure you read the guides they send via email before you come so you pack correctly and know what to expect and bring--the guide includes everything so that there are no surprises, and we knew exactly what to expect, although our stay exceeded our expectations! I highly, highly recommend staying here, it was magical, it was a once in a life time adventure, and I will never forget it. I also want to shout out the manager of the lodge, I forgot her name, but she was incredible, as well as the service staff at meal times, who were so kind and helpful to point out what was vegan all of the time. I truly hope we can come back some day!! Read all

The lodge was kept very clean, and the staff paid close att to people's needs. It was very easy find activities and the guides were excellent with a genuine intended approach towards sustainability and environment longevity. Read all

A superb stay in a top class Lodge which gave a wonderful insight into the Amazon wildlife. Our guide was Juan Carlos who has incredible knowledge and a lovely sense of humour. The staff in the lodge were so friendly and the meals provided were something to look forward to. A wonderful experience! Read all

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