Keep going, stay positive

Actress Amy Poehler often plays upbeat characters, but the comedian brims with pep in Pixar's animated film "Inside Out" as Joy, an emotion living inside an 11-year-old girl named Riley.

When Riley moves to a new city, Joy teams up with Sadness to boost Riley's well-being.

Ahead of the film's Friday debut, Poehler, 43, said "Inside Out" let her cultivate her comedic talent. Below are interview excerpts.

Q: How did you develop a character out of an abstract idea?

A: When you're doing any kind of comedic performance, you have to figure out what are the rules of this character? Joy has very specific rules: Keep going, stay positive, stay in the moment, don't overthink it. She does that because she has fear that things are going to turn sad. It was fun to play a character that had an arc. Suddenly Joy's crying halfway through the movie.

Pixar does a great job in always not condescending to their audience. They don't make "kids movies." I love their brave attempt to go in, when a lot of movies these days are about external disasters and fabricated bad guys. Pixar decided … we're going to make the setting an 11-year-old girl.

Q: What did you enjoy from the experience?

A: Pixar is the gold standard. It's like any project, though … Does the project come from an authentic place? Is there a person with a really specific voice at the helm? Are you working with talented people who like to collaborate? All those boxes were checked.

Q: What's the connection to Smart Girls, your website and video series that emphasize women's empowerment?

A: Smart Girls is a sneaky attempt to be an antidote to some of the other stuff kids are watching. It's just funny, original content … that celebrates that great age in a young girl's life right before she's been confused by all the wonderful things puberty has to offer. It's celebrating this person who's just learning to be herself. As an adult, Smart Girls, for me, is an attempt to get back to that. "Inside Out" is trying to do that too.

Q: Is there anything you wish you had been asked?

A: I don't think enough people have asked me if they think I might be up for a Grammy for the "Bing Bong" song! I'm hoping that I'll be submitted for Best Live Vocal Performance in an Animated Film about Personified Emotions.

DNA May Help Track Ivory Poachers

DNA evidence retrieved from elephant dung, tissue and hair can help identify the origins of illegal ivory, a new study finds. Researchers at the University of Washington and Interpol developed a method to extract DNA from samples of ivory, and compared the gene sequences with those obtained from dung and tissue samples.

More than 85 percent of the forest elephant ivory seized between 2006 and 2014 came from elephants in northeast Gabon, the northwest of the Republic of Congo, southeast Cameroon, and an adjacent reserve in the southwest of the Central African Republic.

The researchers found that more than 85 percent of the savanna elephant ivory seized between 2006 and 2014 came from elephants in East Africa. The findings could help target poachers: About 50,000 African elephants are killed each year, and the animals are at risk of extinction.

Toddlers Have Sense of Justice, Study Shows

Children as young as age 3 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 Dr. 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,” Dr. 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.”

An Ant with the Right Coat for the 158-degree weather

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.

A Sahara Silver Ant. A unique coat of hair covers silver ants of the Sahara and keeps them cool, a discovery with potential practical applications for humans.

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,” Dr. 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, Dr. Yu said.