This is Scientific American's 60-second Science, I'm Susanne Bard.
Anyone who commutes by car knows that traffic jams are an inevitable part of life. But humans are not alone in facing potential backups. Ants also commute—between their nest and sources of food. The survival of their colonies depends on doing this efficiently.
"The more they are, the more food they're going to bring back. But at the same time, they might end up with traffic jam because there are too many of them."
Arizona State University mathematician Sebastien Motsch. When humans commute, there's a point at which cars become dense enough to slow down the flow of traffic, causing gridlock. Motsch and his colleagues wanted to know if ants on the move could also get clogged. So they manipulated traffic density by constructing bridges of various widths between a colony of Argentine ants and a source of food. Then they waited and watched.
"The goal was to try to find out at what point they are going to have a traffic jam. But it appears that that never happened. They never, at one point, just stopped. They always managed to avoid traffic jam."
The flow of ants did increase initially as ants started to fill the bridge and then leveled off at high densities. But it never slowed down, even when the bridge was nearly saturated with ants. The researchers then took a closer look at how the behavior of individual ants impacted traffic as a whole. That meant meticulously tracking thousands of separate ants as they made their way across the bridge.
Motsch and his team found that when ants sense overcrowding, they adjust their speeds and avoid entering high-density areas, which prevents congestion. These behaviors may be facilitated by pheromones, chemicals that tell other ants where a trail is. The ants also manage to avoid colliding with each other at high densities, which could really slow them down.
The study is in the journal eLife.
Can ants help us solve our own traffic problems? Not likely, says Motsch. That's because when it comes to getting from point A to point B as fast as possible, human drivers put their own goals first. Individual ants have to be more cooperative in order to feed the colony. But the research could be useful in optimizing traffic flow for self-driving cars, which can be designed to be less like selfish humans—and more like ants.
Thanks for listening for Scientific American's 60-second Science. I'm Susanne Bard.
开车通勤的人都知道，交通堵塞是生活中不可避免的一部分 。但并非只有人类面临潜在的堵塞问题 。蚂蚁也会通勤——往返于巢穴和食物来源之间 。蚂蚁群体的生存依赖于高效通勤 。
“蚂蚁越多，它们带回来的食物就越多 。但与此同时，它们可能会因个体数量太多而最终陷入堵塞 。”
亚利桑那州立大学的数学家塞巴斯蒂安·莫奇说到 。就人类通勤而言，当汽车密度达到足以减缓交通流量的程度时，就会导致交通堵塞 。莫奇及其同事想知道，移动中的蚂蚁是否也会堵塞 。因此，他们通过在阿根廷蚁群和食源地之间建造不同宽度的桥梁来控制交通密度 。之后他们便等待观察 。
“目标是试图找出它们何时会遭遇交通堵塞 。但似乎这种情况从未发生 。它们从来没有停下 。它们总是能成功避开交通堵塞 。”
最初，当蚂蚁开始爬满桥梁时，蚂蚁的流量的确会增加，然后稳定在高密度 。但流量从未下降，即使桥上几乎遍布蚂蚁时 。之后，研究人员仔细观察了蚂蚁个体行为对交通的整体影响 。也就是说，他们认真地追踪了过桥的数千只蚂蚁个体 。
莫奇及其团队发现，当蚂蚁觉察到过度拥挤时，它们会调整速度，避免进入高密度地区，从而避免拥堵 。这些行为可能由信息素促成，信息素是告诉其它蚂蚁哪里有路径的化学物质 。蚂蚁还设法在高密度情况下避免相互碰撞，这的确会令它们减慢速度 。
蚂蚁能帮助我们解决交通问题吗？莫奇说，不太可能 。因为就尽快从A点到B点而言，人类司机会将自已的目标放在首位 。而为了喂养蚁群，蚂蚁个体不得不更加合作 。但这项研究可能有助于优化无人驾驶汽车的交通流量，可以将这类汽车设计得不那么像自私的人类，而更像蚂蚁 。
谢谢大家收听科学美国人——60秒科学 。我是苏珊娜·巴德 。
1. depend on 依靠；依赖；
These charities depend on the compassionate feelings and generosity of the general public.
2. level off （数字或数量）趋向平缓，趋于稳定；
The figures show evidence that murders in the nation's capital are beginning to le vel off.
3. as a whole 整体而言；总体上；
The pupil's answers may not have been reflective of what the class as a whole had understood.
4. put sth. first 视…为最重要；把…放在首位；
We believe that quality is the soul of an enterprise. therefore, we always put quality first.