At over three feet, you’d think the solo coral grouper would be threatening enough. Threatening sure, but a successful lone hunter? Well, not so much, according to National Geographic News Watch:

When hunting alone, groupers only catch their prey about 1 out of every 20 attempts.

So the grouper teams up with the even fiercer moray eel, or the very large Napolean wrasse, to go hunting. The fish are looking for smaller coral reef fishes that hide from their predators under rocks and coral. When the grouper detects the hiding prey, it signals its hunting friend and together they both flush the prey out of hiding.

The cooperation, however, ends there. Whoever gets the prey, eats it whole. There’s no sharing of the spoils. Still, for the grouper, it’s worth the shared hunting, says National Geographic News Watch:

When they have help, the ratio is significantly better—about one out of seven.

What’s most significant about this shared hunting are the signals the grouper makes to its partner during the hunt, say scientists. Researchers studying the fish observed dozens of events where groupers performed upside-down headstands with concurrent head shakes to indicate the presence and location of particular prey to cooperative partners. Their study, published last week in Nature Communications, call the groupers’ signals “referential gestures”. From the abstract:

In humans, referential gestures intentionally draw the attention of a partner to an object of mutual interest, and are considered a key element in language development. Outside humans, referential gestures have only been attributed to great apes and, most recently, ravens.

It’s likely that these gestures have been understudied in non-primate species, say Academy researchers, who point to hunting dogs and even bee dances as potential consideration for referential gestures.

The researchers of the study say that the mental processes underlying these gestures in fish, apes and ravens are unclear and may well vary among these taxa. Their findings point to the fish having developed cognitive skills according to their particular ecological needs.

Whatever the cause, these hunting tactics are pretty extraordinary. Videos of the behaviors can be found here. For more information on the study, visit the University of Cambridge website.

Image: jon hanson/Wikipedia

The finding builds on research as early as the 1940s that found these whales sound like human children. In the 1970s, an animal at the Vancouver Aquarium was heard to say his own name, Lugosi.

This time, scientists at the National Marine Mammal Foundation (NMMF) conducted acoustic analysis of a beluga named NOC in their facility in San Diego. It all started in 1984 when staff began to notice some unusual sounds in the vicinity of the whale and dolphin enclosure. It sounded as though two people were conversing in the distance, just out of range of their understanding. They traced the sounds to NOC a bit later when a diver surfaced from the whale enclosure to ask his colleagues an odd question: “Who told me to get out?”

They recorded the whale’s sounds to reveal a rhythm similar to human speech and fundamental frequencies several octaves lower than typical whale sounds, much closer to that of the human voice.

In general, whales make sounds via their nasal tract, not in the larynx as humans do. But the scientists found that NOC had to vary the pressure in his nasal tract while making other muscular adjustments and inflating the vestibular sac in his blowhole—a tricky maneuver.

“Our observations suggest that the whale had to modify its vocal mechanics in order to make the speech-like sounds,” says Sam Ridgway of NMMF. “Such obvious effort suggests motivation for contact.”

Sadly, after 30 years at the National Marine Mammal Foundation, NOC passed away five years ago. But the sound of his voice lives on—listen here.

Image: Greg Hume/Wikipedia