Monkey toys and scary news about bees

Interesting bits of news today, both of which deal with a recognition that non-human animals are more human-like than previously thought:

1. A Texas A&M study suggests that biological pre-wiring determines why boys and girls enjoy playing with different toys, not sociological factors. Psychologist Gerianne Alexander says it’s commonly believed boys and girls learn what types of toys they should like based solely on society’s expectations. But she says her research brings that into question. Alexander, who studies sex differences in behavior and biological factors that influence them, examined monkeys as they interacted with toys.

She and Melissa Hines of the University of London found monkeys’ toy preferences are consistent along gender lines as those of human children. Young male monkeys enjoyed playing with model cars and young female monkeys preferred dolls. "Masculine toys and feminine toys," Alexander says, "are clearly categories constructed by people. However our finding that male and female vervet monkeys show similar preferences for these toys as boys and girls do, suggests that what makes a ‘boy toy’ and a ‘girl toy’ is more than just what society dictates – it suggests that there may be perceptual cues that attract males or females to particular objects such as toys."

The study appeared earlier this year in the journal "Evolution and Human Behavior."

2. Honeybees may look pretty much all alike to us. But it seems we may not look all alike to them. A study has found that they can learn to recognize human faces in photos, and remember them for at least two days. The findings toss new uncertainty into a long-studied question that some scientists consider largely settled, the researchers say: how humans themselves recognize faces. The results also may help lead to better face-recognition software, developed through study of the insect brain, the scientists added. Many researchers traditionally believed facial recognition required a large brain, and possibly a specialized area of that organ dedicated to processing face information. The bee finding casts doubt on that, said Adrian G. Dyer, the lead researcher in the study.

He recalls that when he made the discovery, it startled him so much that he called out to a colleague, telling her to come quickly because "no one’s going to believe it – and bring a camera!" Dyer said that to his knowledge, the finding is the first time an invertebrate has shown ability to recognize faces of other species. But not all bees were up to the task: some flunked it, he said, although this seemed due more to a failure to grasp how the experiment worked than to poor facial recognition specifically. In any case, some humans also can’t recognize faces, Dyer noted; the condition is called prosopagnosia.

In the bee study, reported in the December 15 issue of the Journal of Experimental Biology, Dyer and two colleagues presented honeybees with photos of human faces take from a standard human psychology test. The photos had similar lighting, background colors and sizes and included only the face and neck to avoid having the insects make judgments based on the clothing. In some cases, the people in the pictures themselves looked similar. The researchers, with Johannes Gutenberg University in Mainz, Germany, tried to train the bees to realize that a photo of one man had a drop of sugary liquid next to it. Different photos came with a drop of bitter liquid instead. A few bees apparently failed to realize that they should pay attention to the photos at all, but five bees learned to fly toward the photos horizontally in such a way that they could get a good look at it, Dyer reported. In fact, these bees tended to hover a few centimeters in front of the images for a while before deciding where to land. The bees learned to distinguish the correct face from the wrong one with better than 80 percent accuracy, even when the faces were similar, and regardless of where the photos were placed, the researchers found. Also, just like humans, the bees performed worse when the faces were flipped upside down. "This is evidence that face recognition requires neither a specialized neuronal circuitry nor a fundamentally advanced nervous system," The researchers wrote, nothing that the test that used was one for which even humans have some difficulty.

Moreover, "Two bees tested two days after the initial training retained the information in long-term memory," they wrote. One scored about 94 percent on the first day and 79 percent two days later; the second bee’s score dropped from about 87 to 76 percent during the same time-frame.