Stunning: Elephants ‘understand human gesture’

Most everyone has heard the notion of a memory like an elephant’s. Now you maybe be able to add smarts to that, thanks to a study published Thursday in the journal Current Biology. The idea to take away from this story is that elephants definitely get the point.

The finger point that is. Richard Byrne, a professor of evolutionary psychology at the University of St. Andrews in Scotland, studied the behavior of 11 African elephants at a wildlife research and rehabilitation center in Zimbabwe. In this specific study, an experimenter would stand between two buckets—one with a treat and one without a treat—and point at the bucket with the treats. The researchers found that that the elephants would investigate inside a container 68 percent of the time if a human points to it. A 1-year-old human will look at the indicated container about 78 percent of the time.

What makes this study unique is that unlike most other experiments where the animals are first trained to expect a treat for guessing correctly, based on Pavlov’s theory, these elephants were not. “Our results show that elephants spontaneously attend to and correctly interpret human … gestures without extensive prior learning opportunities — the only nonhuman species so far to show this ability,” wrote Byrne and his graduate student coauthor, Anna Smet.

Elephants now enter the realm of domesticated animals such as cats and dogs that have shown to pick up on human cues like pointing. This trait has been a topic of debate as to why it happens. Some have argued that the trait has evolved over time from close interactions with humans, and others believe it may be an innate ability of group-living animals.

The latter view is supported by the theory that animals in herds or groups would need to be able to pick up on cues from others in their group in order to effectively hunt or evade predators. The results from this study seem to support this theory.

“We suggest that the most plausible account of our elephant’s ability to interpret even subtle human pointing gestures as communicative is that human pointing … taps into elephants’ natural communication system,” the authors wrote.

That said, other social animals have been shown not to have this same ability (we’ll ignore the human joke here). “Surprisingly, Asian elephants have been found not to respond to human-given gestural cues,” authors wrote.

Source:http://natmonitor.com

Elephants Get the Point

The next time you need to show an elephant where something is, just point. Chances are he’ll understand what you mean.

New research shows elephants spontaneously understand the communicative intent of human pointing and can use it as a cue to find food.

Richard Byrne and Anna Smet of the University of St. Andrews tested 11 African elephants on what’s known as the object-choice task. In this task, a food reward is hidden in one of several containers and the experimenter signals which one by pointing to it.

People understand pointing, even as young children. But the track record of other animals on the object-choice task is mixed. Domesticated animals, such as dogs, cats, and horses, tend to perform better than wild ones. Even our closest relative, the chimpanzee, typically struggles to understand pointing when it’s used by human caretakers.

What’s so remarkable about the elephants’ success on the object-choice task is that they did it spontaneously. Byrne says that in studies of other species, the animals have had the opportunity to learn the task. This is usually during the experiment itself, which consists of a prolonged series of tests over which the animals come to realize they will get rewarded with food if they follow the line of the human’s pointing.

But the elephants performed as well on the first trial as on later tests and showed no signs of learning over the course of the experiments. The elephants Byrne and Smet tested are used to take tourists on elephant-back rides in southern Africa. They were trained to follow vocal commands only, never gestures. Smet recorded the behavior of the elephants’ handlers over several months and found they never pointed their arms for the elephants. What’s more, the elephants’ ability to understand human pointing did not vary with how long they had lived with people, nor with whether they were captive-born or wild-born. “If they have learned to follow pointing from their past experiences, it’s mystery when and how,” Byrne says. “Rather, it seems they do it naturally.”

In the experiment, Byrne and Smet varied several parameters that often affect children’s and animals’ performance on the task: whether the pointing arm was nearest the correct choice or not; whether the pointer’s arm crossed the body or was always on the side of what was pointed at; and whether the arm broke the silhouette from the elephant’s viewpoint or not. None of these made any difference. Even when the experimenter stood closer to the wrong location than the correct location, the elephants performed a little worse but still mostly responded to where her arm was pointing.

The only condition that truly stymied the elephants was when the experimenter simply looked at the correct location without pointing. Byrne says that elephant eyesight is poor compared to our own, and researchers who work with elephants have commented on how bad they are at identifying things by sight. “It would perhaps have been surprising if they had spontaneously responded to the rather subtle movements of a small primate’s head!” Byrne says.

Elephants are only distantly related to humans, which means that the ability to understand pointing likely evolved separately in both species, and not in a shared ancestor. But why would elephants attend to and understand pointing? One thing elephants do share with humans is that they live in a complex and extensive social network in which cooperation and communication with others play a critical role. Byrne and Smet speculate that pointing relates to something elephants do naturally in their society. “The most likely possibility is that they regularly interpret trunk gestures as pointing to places in space,” Byrne says. Elephants do make many prominent trunk gestures, and Byrne and Smet are currently trying to determine if those motions act as “points” in elephant society.

Reference:
Smet, Anna F. and Byrne, Richard W. (2013). African Elephants Can Use Human Pointing Cues to Find Hidden Food. Current Biology http://dx.doi.org/10.1016/j.cub.2013.08.037

Source:http://www.wired.com

Sex kills for some male marsupials, research finds

Sydney - Mating is such an arduous and frenzied process for some male marsupials that it literally kills them, according to new Australian-led research.

Scientists had wondered for decades why some species of insect-eating marsupials dropped dead after sex, with speculation including that they died from fighting or to leave more food for their offspring.

But research published in the US-based Proceedings of the National Academy of Sciences puts the "dying off" down to the animals' extreme efforts to ensure their sperm is successful in the short once-a-year window that females offer to mate.

"There's always a cost to reproducing - it's an energy expensive thing that animals do," lead researcher, mammal ecologist Diana Fisher from the University of Queensland, explained on Tuesday.

"But in this case they haven't spread out their effort over time, they do it all at once in a really short time. And they just die afterward."

Cascade effect

Organisms that mate once and then die are common among plants and some fish, but rarer among mammals.

Among the exceptions are some species of small marsupials including the mouse-like antechinus and the phascogales, which is more like a possum.

Fisher said the male marsupials that die are so intent on mating that their high testosterone levels trigger a cascade effect of stress hormones, which causes the animals' body tissue to break down and their immune systems to collapse.

"They mate for 12 or 14 hours at a time with lots of females, and they use up their muscle and their body tissues and they are using all of their energy to competitively mate, that's what they are doing. It's sexual selection," she said.

"They just kill themselves mating in this extreme way."

The study, which included researchers from the University of Sydney and the University of Tasmania, compared 52 species of marsupials in Australia, Papua New Guinea and South America - not all of which self-destructed after sex.

"We demonstrate that short mating seasons intensified reproductive competition between males, increasing male energy investment in copulations and reducing male post-mating survival," the paper said.

Fisher said, in the case of some of the marsupials, their life-and-death mating system seemed a shame.

"They have a nice temperament, they are very inquisitive little animals. They are quite interactive. It's a bit sad. But they don't know it's coming I suppose, it's just something that happens to them," she said.