Coat keeps ant cool during extreme heat
Silver ants of the Sahara leave their underground nests for only 10 to 20 minutes a day, and they do it when the heat is peaking. The surface temperature can reach 158 degrees Fahrenheit.
The ant, just three-eighths of an inch long, survives because of a unique coat of hair that covers its body and cools it, researchers report in the journal Science.
The hairs, laid out in triangular cross sections, are highly reflective under visible and near-infrared light. The researchers also discovered that in the mid-infrared portion of the electromagnetic spectrum, the hairs dissipate heat through thermal radiation.
The hairs are critical to the ants’ survival, said Nanfang Yu, a physicist at Columbia University and one of the study’s authors.
“That hottest moment of the day is when they can find the largest quantity of dead insects,” Yu said. “Just a bit later, and those insects may be blown away by the wind or buried by the sand.”
In the extreme heat, the ants also can avoid predatory lizards. The hair on the ants may inspire the development of paints and other materials that can be applied to cars or rooftops, Yu said.
Study finds toddlers have a sense of justice
Children as young as 3 years old will intervene on behalf of a victim, reacting as if victimized themselves, scientists have found.
With toys, cookies and puppets, Keith Jensen, a psychologist at the University of Manchester in England, and his colleagues tried to judge how much concern 3- and 5-year-olds had for others, and whether they had a sense of so-called restorative justice.
In one experiment, when one puppet took toys or cookies from another puppet, children responded by pulling a string that locked the objects in an inaccessible cave. When puppets took objects directly from the children themselves, they responded in the same way.
“The children treated these two violations equally,” said Jensen, a co-author of the study published in the journal Current Biology.
In another experiment, when an object was lost or stolen, children tried to right the wrong by returning the object to the puppet it belonged to.
“Their sense of justice is victim-focused rather than perpetrator focused,” Jensen said. “The take-home message is that preschool children are sensitive to harm to others, and given a choice would rather restore things to help the victim than punish the perpetrator.”
– New York Times