Throughout the tropics, ants and Acacia trees live together in intricate interdependent relationships that have long fascinated scientists.

Now researchers are reporting that in Africa, this plant-insect teamwork depends on the very antagonist it is intended to ward off: Africa's big browsing mammals.

Researchers report that elephants, giraffes and other large plant-eaters spur Acacias to "hire" and support ants as bodyguards -- and without the mammals, the trees slash their investment in ants, opening both to other attackers.

Acacias are mostly shrubby trees common across the tropics and sub-Saharan African savannah. They have swollen thorns that serve as nests for three species of biting ants. Healthy trees have hundreds of the thorns, often containing more than 100,000 ants per tree. Both the ants and the trees benefit from their close cohabitation. The ants get the thorny shelters, as well as nectar they collect from the bases of Acacia leaves. Because the ants swarm in defense against anything that molests the trees, the trees get protection from their chief ostensible nemeses, browsing animals.

That's when the mutualism is working well. But the research got its start when Palmer noticed that certain Acacias at his research site in central Kenya, which had been fenced off from wild herbivores, looked sickly compared with their unfenced counterparts. That was the opposite of what might be expected, because the browsers feed voraciously on the trees.

Without mammals around to eat the trees, sheltering fewer, less aggressive ants would not present a cost to the trees.

But the research revealed that the fewer colonies of weakened ants become less able to defend their territory from another species of ant that, unlike the others, does not have a mutually beneficial relationship with Acacias. Instead, this fourth ant species feeds away from the tree and does not protect it from attackers -- in fact, it actually encourages a destructive, wood-boring beetle whose cavities then serve as this ant's home.

The result appears to be that the trees untouched by browsing mammals are infested with more of the beetles, which is part of the reason that they fare poorly.

One irony of the findings is that the trees have developed their mutualistic relationship with the ants to protect themselves against plant-eating mammals -- and yet because of that relationship, the trees wind up actually needing the mammals.

"If you get rid of the large mammals, it shifts the balance of power, because the trees default on their end of the bargain," Palmer said. "When the trees opt out, their hard-working employees starve and grow weak, which causes them to lose out. So, ironically, getting rid of the mammals causes individual trees to grow more slowly and die younger."

The research has important implications for conservation.

Will Wright's original SimCity has now gone open-source under the GNU General Public License. Though the name and some code have been changed due to EA's requirements, the core of the title remains intact and is now open for the public. This follows the inclusion of SimCity into the OLPC project.

Originally written in C, the open-source version has been "recast into C++ classes, integrated into Python, using the wonderful SWIG interface generator tool." For tinkerers, a lot of the old bugs and code issues remain intact.

The open-source version is now available on Don Hopkins' web site.

One Laptop Per Child.

Young Japanese people are evolving a new lifestyle for the 21st century based on the cellphones that few are now able to live without.

They are using their phones to read books, listen to music, chat with friends and surf the Internet -- an average of 124 minutes a day for high school girls and 92 minutes for boys.

While the wired world they now inhabit holds enormous advantages for learning and communicating, it also brings a downside, say experts who point to a rise in cyberbullying and a growing inability among teenagers to deal with other people face to face.

"Kids say what's most important to them, next to their own lives, is their cellphone," said Masashi Yasukawa, head of the private National Web Counselling Council.

"They are moving their thumbs while eating or watching television," he said.

The passion in 20-year-old Ayumi Chiba's voice backs up this assertion.

"My life is impossible without it," she says of her cellphone. "I used to pretend I was sick and leave school early when I forgot to take it with me."

As the multi-faceted cellphone takes centre stage in teen life, it plays a number of roles -- including a weapon that children can wield against each other with no thought for the consequences.

Yasukawa recalls the case of a 15-year-old girl who regularly received messages telling her: "Die," "You're a nuisance" and "You smell".

They turned out to have been sent by a friend in whom she had confided and who told her not to take the messages too seriously.

"The girl who was doing the bullying confessed it made her feel good to see the unease spreading on her friend's face," Yasukawa said.

Most middle school cellphone users rarely used their phone to talk, the survey found. Saito, of Kawamura Gakuen Women's University near Tokyo, said children seemed to want the security of communicating with someone, without the bother of dealing with a real person.

"Communication ability is bound to decline as cellphones and other devices are now getting between people," he said.

Saito's survey found that students can also use their cellphones as an emotional crutch, and the more problems they have at home, the more dependent they seem to become on their phones.

More than 60 percent of students who said they do not enjoy being with their families send 20 or more emails a day, compared with 35 percent of those happy with their families.

Related:

South Korea Opens Boot Camp to Confront Internet Addiction.

Neither British colonists nor Christian missionaries nor government entities could tamp down conflicts among tribes in this remote South Pacific island nation. But when turtles started disappearing, the local people finally started talking.

The Solomon Islands, a remote Pacific archipelago strung southeast of Papua New Guinea, are probably best known as the site of the World War II Battle of Guadalcanal. But they also contain some of the world’s most important nesting grounds for hawksbills. On these beaches, the turtles haul their 150-pound bodies out of the surf and bury hundreds of thousands of eggs in the crushed-coral sand. For the hatchlings that survive, this becomes their hard-wired home, the place to which they’ll return to lay their own eggs.

The Arnavons Community Marine Conservation Area—encompassing 40,000 acres, three small uninhabited islands, flourishing reefs, fish-filled lagoons and beaches that are home to thousands of egg-bearing turtles—is run by an improbable cast of characters. A band of reformed arsonists, poachers and unreformed turtle eaters has teamed up with the Solomon Islands government and The Nature Conservancy to reimagine conservation around their own worldview. At the heart of the project are three communities on Choi-seul, Santa Isabel and Waghena islands—a mix of tribes and cultures who argued over the use of the neighboring Arnavon Islands until agreeing on no use.

This is the first community-run marine protected area in the South Pacific. Now going on 12 years, the project is showing that well-managed protected areas promote healthy communities of turtles and other marine life and also improve the lives of human communities. And a recent anonymous gift to the Conservancy has completed an endowment that will provide sustainable financing for the project—a first for a marine protected area. Says Zama, “It’s up to the three of us [communities] now.”

To fully appreciate the significance of this peaceful arrangement, it helps to understand the violent history that serves as its backdrop.

..

“Nowadays we only eat turtles for feasts,” Bako says. “It is our kastom.” Such customary feasts are long-standing traditions in Pacific island nations. A turtle on the table for an important birth, death or religious holiday in the Solomons is the equivalent of a Thanksgiving turkey. And in a country where 85 percent of the population depends entirely on natural resources, turtles—even endangered ones—remain an important part of the subsistence diet.

The British colonial government in 1963 resettled the people of the Gilbert (now Kiribati) Islands to the Solomons. The Gilbertese built a village on Waghena, which put the newcomers closer to the Arnavons—and the islands’ abundant marine resources—than either indigenous community on Choiseul or Isabel. Inter-island resentment intensified, and the communities again were in conflict—this time arguing over claims to the Arnavons. The Gilbertese were being blamed for the depletion of resources.

“Some people, when they harvest, they don’t have a controlled harvest,” says Bako. “It’s like a sport: Who will be the champion?”

Edward mayer and Susan Brown are like marriage counselors for conservation. They help partners hash out differences, build trust and collaboration, and cultivate common interests. In 1993, when the Conservancy first entered the picture in the Arnavons, its goal was to get stakeholders talking.

And it took lots of talking before the landowners on Choiseul and Isabel were willing to welcome Waghena residents as a full project partner. Yet it was “the Gilbertese who had the most to lose from the formation of the conservation area,” says the Conservancy’s Thomas. “It is to their credit that they came to the party.” Once they did, the group set up a management committee for the Arnavons Community Marine Conservation Area. The committee was made up of two representatives from each community, three government representatives and Mayer, who tried not to say much. “A lot of the dynamic,” he says, “had to do with how open we were to listening.” Mayer emphasizes the value of consensus among the communities.

As for the three communities on Choiseul, Isabel and Waghena, disputes over the Arnavons may never be fully resolved. But leaders of all three communities seem willing to look beyond those differences for the good of the whole.

Most Marine protected areas (MPAs) are designed to contain zones with different uses that preserve and enhance recreational, commercial, scientific, cultural and conservation goals. Often, their main purpose is to reduce or eliminate harmful extractive activities, such as overfishing.

Scientific evidence shows that MPAs can help preserve and increase the overall diversity and abundance of marine species. By creating networks of MPAs, the Conservancy aims to ensure that ocean and coastal habitats have a better chance of surviving catastrophic events, such as warming waters that bleach corals.

Photographer Jeff Yonover shot these jaw-dropping underwater images (slideshow) in many of the places The Nature Conservancy works — Kimbe Bay and New Britain Island of Papua New Guinea as well as the Solomon Islands. (Natural Light Photos)

The Last Town on Earth by Thomas Mullen.

The Children of Húrin by J.R.R. Tolkien.

Harry Potter and the Deathly Hallows by J. K. Rowling.

Related: The Deathly Hallows and The Tale of The Three Brothers.

The Alchemist by Paulo Coelho.

Warrior of the Light by Paulo Coelho.

Miracle in the Andes by Nando Parrado, Vince Rause.

Teach Yourself Korean by Mark Vincent and Jaehoon Yeon. (partial)

The Koreans: Who They Are, What They Want, Where Their Future Lies by Michael Breen.

Al Jazeera: How the Free Arab News Network Scooped the World and Changed the Middle East by Mohammed El-Nawawy, Adel Iskandar.

Life's Missing Instruction Manual : The Guidebook You Should Have Been Given at Birth by Joe Vitale.

The Art of Happiness at Work by Dalai Lama and Howard C. Cutler.

The Zen of Listening by Rebecca Z. Shafir.

How to Be Your Own Therapist: A Step-by-Step Guide to Taking Back Your Life by Patricia Farrell.

Theory and Practice of Counseling and Psychotherapy by Gerald Corey.

Uncommon Therapy: The Psychiatric Techniques of Milton H. Erickson by Jay Haley.

Related: A Humorous Milton Erickson Therapy Case.

Buddhism And Psychotherapy Across Cultures by Mark Unno.

Related: Buddhism And Psychotherapy Across Cultures.

The Universe in a Single Atom: The Convergence of Science and Spirituality by Dalai Lama.

Related: Dalai Lama on Theory of Emptiness.

Modern Buddhist Healing: A Spiritual Strategy for Transforming Pain, Disease, and Death by Charles Atkins.

Lovingkindness: The Revolutionary Art of Happiness by Sharon Salzberg.

Gateless Barrier: Zen Comments on the Mumonkan by Zenkai Shibayama. (partial)

The Sun My Heart by Thich Nhat Hanh.

Related: Meditation on Interdependence.