(Addendum below.) This appears to be a green tree python (Morelia viridis, SE Asia and Australia); notice how it remains absolutely motionless but waves its brightly-colored tail, a behavior called “caudal luring.” As this paper in Herpetologica notes:
Caudal luring by ambush-foraging snakes can increase their encounter rates with prey (Neill, 1960). The wiggling of a brightly colored tail presumably mimics the movements made by insect larvae, which are prey items of frogs and lizards (Greene and Campbell, 1972). Frogs and lizards are attracted to the lure and become prey themselves when they move within striking distance of the snake (Greene and Campbell, 1972). The use of this behavior as a foraging strategy has been well documented in viperids, but previous studies did not test whether this behavior varies among age classes or sexes.
Another paper on caudal luring in the green python reports the behavior in young snakes when rodents and lizards (Anolis) were offered. But luring diminished with age, corresponding to a change in the color of the tail tip from bright yellow to the green “ground color” of the adult body. The authors suggest that the lure could be used to attract insectivorous marsupials, birds, and other reptiles. I’m not sure why the behavior and tail color diminish with age—presumably the snakes use other methods of hunting when they’re older.
h/t: Matthew Cobb via Ed Yong (Twitter) via (I think) the snake’s owner.
Addendum by Greg Mayer: I posted on caudal luring in Mexican moccasins a little while back:
http://whyevolutionistrue.com/2012/01/14/cantilurday-viperid-mexican-mocassin/
The video above is great! I’d never seen that kind of movement, and it clearly seems to be predatory in intent. Just last week, I was giving a demo of a green tree python at the Racine Zoo; I don’t recall if the one we have at the Zoo has a differently colored tail. The species is famous for being yellow or red as juveniles, and turning green when they get bigger. The color change is accompanied by an ecological change from ground-dwelling, lizard-eating juveniles, to canopy-dwelling, bird-eating adults. David Wilson, Robert Heinsohn, and John Endler have shown that the color change makes them less conspicuous in their respective habitats. Jerry’s remark about changing habits as they age is absolutely right– they change color, where they live, and what they eat.
There’s a nearly identically patterned species in South America, the emerald tree boa (Corallus caninus), which has the same ontogenetic color change, and sits on branches the same funny way; I don’t know if they caudal lure or not (the tail is prehensile in both). It’s a remarkable case of convergence, as the species are in different families or subfamilies (depending on if you’re a lumper or splitter).
Caudal movement (which occurs in lizards too) has also been considered a protective behavior, distracting predators from the vital head. There’s some discussion of this in the moccasin post comments. In the tree python, it seems undoubtedly predatory, rather than protective.
For more on snake natural history, with lots on eating and avoiding being eaten see Snakes, by my friend and colleague Harry Greene, one of whose papers is cited above.
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Wilson, D., R. Heinsohn, and J.A. Endler. 2007. The adaptive significance of ontogenetic colour change in a tropical python. Biology Letters 3:40-43. pdf
A) My cats would be so dead if they met that python
B) My cats would be so happy if they could do that python tail thing. Endless fun with each other, without a laser pointer!
I would come home to python guts all over the house, the tail hanging from Lynus’ mouth, and a look on Esqui’s face that said, “We’re done here–you can clean it up now.”
My sister’s chihuahua would do this to my cat – but then fall out of the tree and ruin the element of surprise…
OK, after looking at that, I would be dead. Twitching tail is irresistible. Gotta touch it.
The caudal luring is ace to watch, my one does it all the time. Has done for years. I think it’s a behaviour noted among other pythons and bias also. I seem to remember reading that young Boa Constrictors have been noted to caudal lure also.
We wwre discussing caudal luring in Boa constrictor constrictor (Bcc) and Boa constrictor imperator (Bci) recently on a reptile forum I frequent. The conversation began with the question of why the snakes evolved such a bright constrastingly red tail compared to their dull camouflaged bodies. someone posted a video of hos boa appearing to caudal lure from a raised platform, but this was no baby! It was very interesting, but not seen enough to be a definitive answer to the questions.
I’d love to know If anyone has any thoughts on this.
Red tails in boas are usually a fairly subtle change in the color of the dark markings of the camouflage pattern from brown to brick red, and are not contrastingly bright. I’ve seen photos with more nearly spectrum red on the tail, but these are almost certainly captives that may have been the result of selective breeding. In all cases I’ve seen, the camouflage pattern is unbroken, merely the color of the dark marking changing. That said, the use of caudal luring is very interesting; can you give a link to the video? The green tree python shown luring in Jerry’s original post is an adult (or nearly so).
Gregory,
Please find the link to the Thread. The link to the video is on page 1, fifth post down. If you have any issues viewing it though, the owner has agreed to send a copy directly to me to forward on if necessary.
http://www.reptileforums.co.uk/forums/snakes/850500-boa-tails.html
As for the tail colour, I am no expert as I have only just acquired my first Bci (a hypomelanistic with abberant patterns), however I have been led to believe that, at the very least, the Bcc have very distinct red tails where Bci have brownish/red tails. Having looked at a few images of Suriname and Guyanese Locale Bcc, I have noticed a distinct Red colouring. I think some are wild caught as well, but the captive bred may be down to owners loving the bright colour and breeding with like.
Regards,
Thanks for the link– it works. The clip is very interesting. It would be nice to know more of the context of the behavior– was there a food item in the cage? Wsa it feeding time? A long time since last meal? The snake’s head did not seem oriented at all toward the tail. What the tail movement most reminds me of is the tail wagging done by geckos prior to seizing an insect; it did not seem as deliberately luring as that of the green tree python, but that’s a really subjective assessment by me of the snake’s ‘intentions’.
My woma pythons do this too. It’s a blast to watch. Womas combine it with a head-bobbing behavior, so I’d say it’s definitely predatory rather than protective.
My woma pythons do this too. Womas combine it with a head bobbing behavior… not sure if any other pythons do the head-bob thing as well.
Nature is awesome.
Reblogged this on emmageraln.
The snake didn’t look “absolutely motionless” to me. It was “wav[ing] its brightly colored tail.”
Absolutely motionless would be like a praying mantis.
A guy from Uganda told me how to get the upper hand if you are being crushed by a Python or Boa Constrictor: He said that the snake will stick it’s face under your nose and flick it’s tongue to see if your breathing has stopped. When it does that you bite off it’s tongue, and it will release you and hurry away. Of course, by then just about every bone in your body is crushed, but at least you didn’t end up being a meal for the snake. My Ugandan friend said he had learned this from his father, who lived in Uganda most of his life.
Steve Wagner: people who live in interesting places can never resist telling bullshit stories to tourists. 🙂
(Cool actual tongue facts: Regeneration after amputation of the entire fork! Lingual luring! Smelling in stereo!)
Caudal luring occurs in some (but not all) members of a large number of snake lineages, it must have evolved and been lost a very large number of times. Which means it’s a Good Trick, but not always the right tool for the job.
Snakes do a lot of other cool stuff with their tails too (I’ve published on one or two of them), but it would be fair to mention that they don’t exactly have a lot of different extremities to press into service when a novel function would be advantageous.