But Sonja Wild, a behavioral ecologist at Max Planck Institute of Animal Behavior in Germany, who was not part of the study, was skeptical that the interaction was purposely instructive. It’s more plausible the juveniles were observing because they were curious, she says.
And because anacondas are strong, Dr. Wild wonders if the snake was injured or dead before the dolphins got to it. Of all the things one could pick up, “this seems a little extraordinary,” she said.
“This is the first time I’ve heard of dolphins playing with a large snake,” added Dr. Wild, who has observed bottlenose dolphins using shells as tools.
Something else from the photos was notable — the male dolphins’ erect penises.
“It could have been sexually stimulating for them,” said Diana Reiss, a marine mammal scientist and cognitive psychologist at Hunter College in New York who was not involved with the study. “It could have been something to rub on.”
The aroused males could have been having a sexual romp with each other before the snake became entangled.
Researchers who study dolphins are well aware of the animals’ sexual proclivities, such as rubbing their genitals on toys or inserting their penises into objects, animate and inanimate. They often use their penises for tactile interactions, Dr. Reiss says. She has even observed male bottlenose dolphins trying to penetrate the blowhole of a rescued pilot whale in an aquarium. It’s possible, she added, that the males tried to insert their penises into the snake.
“There are so many questions,” Mr. Entiauspe-Neto says.
A lot more is known about ocean-dwelling dolphins than riverine ones, in part because it’s harder to see what’s going on when river water is muddy. Even though they’re limited in nature, “these observations are always valuable,” Dr. Reiss says. “It’s giving us another glimpse of the lives of these animals, particularly in the wild.”
Whatever happened in this animal encounter, it’s not the stuff of children’s storybooks.