Over the centuries, through genetic and cultural adaptation, humans and a wild bird species have learned to work together .When human honey-hunters make a certain noise, a bird called the honey guide does its job with unbelievable accuracy, leading people to hidden bees' nests.

Scientists put this ancient practice to the test. When biologists compared the honey guide call to other sounds, the traditional sound sent the honey guides to hidden bees nest three times more often than other sounds, according to a study in the journal Science. When you make the right noise, you end up with more honey compared to the wrong noise.

"It's an exchange of information for skills," said study lead author Claire Spottiswoode, an evolutionary biologist at the University of Cambridge.She failed to find bees nests until her friends made the right noise,and then was rewarded with honey that's very rich and delicious.

The honey guide has a special ability to find bees' nests. “Scientists aren't quite sure how it works, but it likely has to do with a sophisticated sense of smell,” Spottiswoode said. Still, there's a problem: These nests are stuck in trees that are difficult for the birds to reach. Even worse, the bees sting the birds, sometime to death.The people of the region, who make a living on the honey, have tools that can get at those nests and they use smoke to chase the bees away, reducing the stinging problem.

It's clear that the birds have adapted in an evolutionary way through natural selection, but for people the arrangement is probably more cultural.

The day had finally arrived. Skyler and Kenny waited expectantly by the door. When they heard the familiar “thump, thump” of their father’s car as it turned off the street and into the driveway, the children ran outside, zipped (快速移动) past their father and hurried into the back seat of the car.

They were greeted by a familiar furry face and a wagging tail. Both face and tail belonged to Daisy, their three-year-old German shepherd. In the seat beside her lay her harness (背带). It was the symbol of Daisy and the children’s hard work. If all had gone well this afternoon, the harness would become Daisy’s work uniform, a sign to the world that she was a fully trained service dog.

Every day for eighteen long months, Skyler and Kenny had trained Daisy to work with the visually impaired: people with sight problems or blindness. First, they trained her to perform the tasks that every obedient dog should know. Daisy learned to sit, to walk on a leash (皮带), and to settle patiently and wait. Those simple tasks came easily to their intelligent pup.

But the more challenging tasks took time and patience. Daisy learned to move carefully around objects like signposts and trash cans. She needed to keep well clear of them in order to guide her owner along a safe path. Daisy learned to stop at the edge of a staircase, or any other spot that required a step up or down. A professional service dog trainer helped with the most challenging tasks. He taught Daisy to ignore orders that might put her owner in danger.

Today, all of their hard work had come to a conclusion. Daisy had taken her service dog exam. But did she pass? Skyler and Kenny followed their father into the front hallway, with Daisy tagging close behind. They looked at their father expectantly. Their father gave a smile and a nod. The children ran off to tell their mother the news.

For every goal that Lesein Mutunkei scores, trees get planted. It’s a simple yet effective message that appeals, and leads to a satisfying way of motivating us to promote environmentalism in our own way.

Born in Nairobi, Lesein is in his late teens, and his Trees4Goals is the means with which he intends to make the world greener. It unites two of his passions in life: love of the outdoors and love of football. Lesein enjoyed walking in the forest. He recognised his country was experiencing a serious loss of tree cover. Between 2001 and 2020, Kenya lost an estimated 11% of trees, releasing 176 million tons of CO₂.

In a blog post for WWF Kenya, Lesein revealed that, once he started the Trees4Goals initiative, he originally planned to plant one tree per goal. In 2020, he wanted to take his efforts even further. What started as one tree planted per goal mushroomed into 11 trees planted per goal. Explaining the reason behind expanding the tree-planting, he said, “It represents team efforts in football and the contribution by my team. I have planted over 1,000 trees in the last two years.”

While it’s something of an own goal to destroy the forests and jungles providing enormous biodiversity, initiatives like Trees4Goals are an assured way to score an environmentalist hat-trick. Sports such as football are popular with the booming Kenyan population and have the ability to cut through cultural barriers regardless of the countries they are played in. Sports have the power to unify and excite large audiences. Lesein Mutunkei has taken this strategy and scored a winning goal of his own.

Like a seed, best ideas start small and change into something that can become far larger than anticipated. While Lesein continues planting 11 trees per goal, the Kenyan government is aiming to plant 1.8 billion trees to reach a point where 10 per cent of the country is covered by trees. The science behind is clear; a report in 2019 claimed that if 900 million hectares were devoted to additional tree planting of half a trillion trees, the world could offset (抵消) half of all carbon emissions produced since 1960.