Animal Intelligence

ScienceNOW: “Is a Dolphin a Person?”

A conversation on dolphin intelligence—and whether dolphins deserve special rights—caused animated discussion at a session of the American Association for the Advancement of Science’s annual meeting. Among the discussants was Emory University neuroanatomist Lori Marino, one of those arguing in favor of special treatment for dolphins.

Experiments suggest dolphins are as intelligent as great apes and perhaps even young children.

Marino argued that studies of the dolphin brain justify giving dolphins a special status. Dolphins have the second biggest brain-to-body-weight ratio of any creature (the first being humans), along with a highly complex neocortex. City University of New York cognitive psychologist Diana Reiss, another discussant, reviewed previous experiments that suggest dolphins are as intelligent as great apes and perhaps even young children.

Even while we appreciate the intelligence God gave dolphins and marvel at their capabilities, we should remember that humans are different from animals in one important way: we were created in God’s image (Genesis 1:27). While we can discuss animal intelligence and what it implies about appropriate animal treatment, even the smartest animals are qualitatively different from humans. Likewise, in this and in the animal intelligence stories that follow, we remember that God created many different kinds of animals that are highly intelligent. Animal cleverness isn’t limited to primates, nor is it a legacy of evolution.

BBC News: “Chimps Are Intelligent Enough to Appreciate a Full Pint”

Chimpanzees are able to distinguish between more and less of a continuous amount of something, such as water or juice, according to new research led by Georgia State University psychologist Michael Beran. This ability is a greater indication of intelligence than the ability to distinguish between discrete numbers of objects, such as individual pieces of fruit. Furthermore, it shows that chimps have some rudimentary understanding of the physics of liquids, BBC News reports.

Beran tested three chimps each in three experiments, progressively more difficult, to gauge their ability to compare quantities of fruit juice. In the first experiment, Beran used a syringe to pour fruit juice into two cups, one clear but the other solid. Afterwards, the chimps chose a cup to drink from. Even as Beran varied the amount of fruit juice poured into each cup—and even though the chimps could not observe the quantity of juice inside the solid cup—the chimps chose the cup with more juice in it more than three-quarters of the time.

In a second experiment, the clear cup was already filled with a certain amount of juice, and Beran filled only the solid cup from the syringe as the chimps watched. Beran explained, “This is a [more] complicated feat because there are no cues such as duration of pouring or height of the liquid that can be used.” Yet the chimps were still able to determine which cup contained more juice most of the time. In the final experiment, Beran played with the height from which he poured the juice, attempting to fool the chimps. Still, the chimps successfully chose the largest quantity more than eighty percent of the time.

ScienceNOW: “Is That a Caveman or Dick Cheney? Crows Know the Difference”

We have covered the intellectual capabilities of crows before, and researchers continue experimenting to determine just how clever they are. University of Washington–Seattle ecologist John Marzluff undertook a study to learn more about crows’ ability to recognize individual people.

Over a period of several years, Marzluff and other researchers used masks to test a large crow population. At five different Seattle-area sites, the scientists nonchalantly walked by crows while wearing one of several rubber masks, recording the crows’ response. Weeks after, one researcher, wearing a specific mask nicknamed “the caveman,” trapped and marked some of the crows. For years later, the scientists continued visiting the sites wearing the full range of masks or wearing no mask at all, but continuing to record the crows’ reaction.

The results show that crows “don’t forget the face of the person who trapped them,” ScienceNOW reports. Typically, less than five percent of crows scold the ordinary passer-by, including those wearing most of the masks or no mask at all. But after the trapping incident, up to two-thirds of the crows would “become upset” upon seeing the caveman mask and would “start scolding, mobbing, and dive-bombing the wearer.” What’s more, the researchers controlled for factors like height, weight, gender, etc., showing that the crows indeed perceived the face itself as representing hostility.

Marzluff has been continuing the experiment, and notes (perhaps humorously), “It’s remarkable . . . it’s been four years now, but they see that mask and still go crazy.”

BBC News: “Elephant ‘Secret Language’ Clues”

Elephants may be able to distinguish between different human languages.

Even standing right next to an elephant, a human could not hear the full elephant “language,” report researchers at the San Diego Zoo, because elephants communicate using sounds that the human ear can hardly pick up. But these elephant “growls” appear to be extremely important in communication between the animals.

Using a low-frequency microphone and a GPS tracking system, zoo researchers “listened” to eight female elephants over time and then attempted to match up the noises with variations in elephant behavior. A key discovery is that pregnant females likely use a particular growl near the end of their pregnancy to “announce” the impending birth. Researchers believe the call also serves to ask other elephants to look out for predators that could threaten the calf.

Project leader Matt Anderson noted, “We’re excited to learn of the hierarchy within the female herd and how they interact and intercede with one another.” Interestingly, we learned last week that elephants may be able to distinguish between different human languages. It seems humans can return the favor!

BBC News: “Sperm Whale Groups ‘May Corral Deep Squid’”

When one thinks of animals hunting in packs, wolves or big cats frequently come to mind. New research suggests that sperm whales may be group hunters, based on electronic tracking of the whales in the Gulf of Mexico.

GPS tracking allowed scientists to indirectly observe a group of whales as they explored the gulf and made squid-hunting dives some 3,300 ft. (1000 m) deep. Although the scientists aren’t sure what the whales were doing, Hatfield Marine Science Center expert Bruce Mate explained, “We can see that they’re actually changing their role over time. And we’re speculating that the animals are herding a ball of squid.” Each time, some whales guarded the perimeter while others dove through the center of a “bait ball,” thought to be taking turns eating. “It may be that each individual takes it in turns to do the most physiologically demanding task—the deep dive,” Mate said.

While one researcher is cautious of the conclusion, Mate defends it based on evidence that dolphins behave similarly. Such dolphin hunting has been caught on film, however.