Photo credit: Will Ericson / © AntWeb.org
Article by Ben Lybarger
Let’s say you’re a plant, and you’ve got this problem with competing vegetation and herbivorous insects all over the place causing you grief. A situation such as this requires some real muscle, but what can you do? You’re just a plant.
Well, if you are a Tangarana tree in the Amazon, the answer is clear: you need to recruit some hot-headed hymenoptera to take care of business.
However, these ants don’t come easy. Sure, your extrafloral nectaries produce some pretty enticing sap, but you need a real “must-have” sort of delicacy to seal the deal. That’s where the aphids come in. These guys are the middlemen in this mutualist arrangement. They feed on the tree sap and excrete some sweet, sweet stuff known to the addicted ant by its street name: “hemipteran honeydew.”
So completely hooked are these ants on these sugary aphid excretions that they not only tend their herd of aphid sap-suckers (trophobiosis) in order to “milk” their… umm, backsides… directly, but they also attack en masse any plant or animal that comes within a meter or so of the tree. Accordingly, you can easily identify a Tangarana tree in the rainforest because it is the scraggly mid-sized tree enjoying an unlikely bounty of sunlight and soil nutrients bothered by nothing but bare earth around it.
A careless human might even choose to lean on the Tangarana’s mottled trunk, taking a moment’s rest in the apparent sanctity of this little clearing in the dense jungle. However, doing so is a big mistake. At first, nothing appears overtly dangerous to the sweaty and beleaguered sojourner, but once the ants sense the vibration they will erupt seemingly out of nowhere from tiny tunnels carved in the trunk and branches. Within seconds, hundreds of angry ants (Pseudomyrmex dendroicus) will beset the unwelcome interloper with painful stings until the confused victim retreats rapidly in a comical display of panicked flailing.
As you might imagine, discussions with locals invariably yield stories of Tangarana trees historically being used to dole out lurid punishments. Some have referred to it as the “adulterer’s tree,” where offenders are tied to the trunk for their transgressions, and though somewhat apocryphal, there is little reason to doubt these accounts. Just last year, two men in Bolivia nearly died after being tied to the trees for days after they were caught stealing motorcycles.
In the end, the Tangarana may be a frail and frumpy sort of tree, but it is backed by some serious fire[ant]power. Much like the head of an organized crime syndicate, it stands in the center of the violence: confident and untouchable.
*To learn more and see actual footage, watch this short this video about the Tangarana tree on Amazon Academy: