Individual crop loads provide local control for collective food intake in ant colonies.
Individual crop loads provide local control for collective food intake in ant colonies.
复制标题
DOI：
10.7554/elife.31730
复制
发表时间：
2018-03-06
期刊：
影响因子：
7.7
通讯作者：
Feinerman O
中科院分区：
文献类型：
--
作者：
Greenwald EE;Baltiansky L;Feinerman O
蚂蚁的营养调节是从分布式过程中出现的：一小部分工人收集食物，存储在个人的农作物中，并通过局部蚂蚁到对象的相互作用进行扩散。不清楚的是由于难以测量蚂蚁农作物中的食物。我们的较旧菌落的觅食者。有趣的是，这些影响并不是我们发现的纯粹的物理局限性。评估殖民地的全球状态。
在一个蚂蚁社会中，一小群工人被称为觅食者，每个觅食者都会出现在巢中，以找到她收集的任何液体食物；她的脚步。
觅食者需要根据其他蚂蚁在任何给定时间需要的食物进行觅食的频率。假设觅食者会充分喂食她在巢中遇到的人，然后在她的农作物空着时进行一次觅食旅行。确认是否是这种情况。
格林瓦尔德（Greenwald），巴尔蒂安斯基（Baltiansky）和费纳曼（Feinerman）现在使用实验室蚂蚁菌落和荧光标记食物来实时监测食物如何在单个蚂蚁之间转移。因此，当实验表明，群落中的昆虫被滋养。他们的农作物的饱满表示整体上的殖民地因此，接收蚂蚁的农作物中的食物控制了进食菌落的多少，以及觅食者卸下其作物的速度。
调节觅食频率的一种可能的机制是，觅食者只有在她感觉到在这种情况下的食物量发生重大变化之后才能进行觅食之旅。自己的农作物：她的小袋里留下的食物越小，她越有可能离开巢穴来带来更多食物。接收蚂蚁农作物，觅食者多久会随着整个殖民地的饥饿水平而改变食物的频率，当蚂蚁饥饿时会有更多的旅行。
这些实验表明，接收和觅食的食物量有助于将其行为适应殖民地的需求。正是觅食者作物的充实的机械变化是这个决策过程。
Nutritional regulation by ants emerges from a distributed process: food is collected by a small fraction of workers, stored within the crops of individuals, and spread via local ant-to-ant interactions. The precise individual-level underpinnings of this collective regulation have remained unclear mainly due to difficulties in measuring food within ants’ crops. Here we image fluorescent liquid food in individually tagged Camponotus sanctus ants and track the real-time food flow from foragers to their gradually satiating colonies. We show how the feedback between colony satiation level and food inflow is mediated by individual crop loads; specifically, the crop loads of recipient ants control food flow rates, while those of foragers regulate the frequency of foraging-trips. Interestingly, these effects do not rise from pure physical limitations of crop capacity. Our findings suggest that the emergence of food intake regulation does not require individual foragers to assess the global state of the colony. In an ant society, a small group of workers, called foragers, feeds the rest of the colony. Each forager goes out of the nest to find food; any liquid food she collects is stored in her ‘crop’, a pouch located just upstream of her stomach. When a forager goes back to the nest, she unloads this liquid by mouth-to-mouth contact into the crops of other ants. The foragers need to adjust how often they go on foraging trips based on the amount of food the other ants require at any given time. However, it is still unclear how foragers can assess the changing needs of the colony. For example, it had been assumed that a forager would fully feed the individuals she encounters in the nest and then go for another foraging trip when her crop is empty. Yet, scientists had not managed to track food transfer at the level of the individual insect to confirm if this is the case. Greenwald, Baltiansky and Feinerman have now used laboratory ant colonies and fluorescently labeled food to monitor in real time how food is transferred between individual ants. Contrary to previous hypotheses, when a forager comes back to the nest, she gives small portions of food to many different ants. The insects in the colony are therefore being nourished through these repetitive interactions. As the experiments show, when a forager meets other ants in the nest, the fullness of their crops reliably represents how full the colony is as a whole. Moreover, the portion that the forager gives is, on average, proportional to the space available in the receiver’s crop: the emptier the crop, the more food is given. The amount of food in the crops of the receiving ants therefore controls how much food enters the colony, and the rate at which a forager unloads its crop. A possible mechanism for regulating foraging frequency is that a forager considers whether or not to go on a foraging trip only after she senses a substantial change in the amount of food in her crop. In this case, her decision is based on the fullness of her own crop: the smaller the amount of food left in her pouch, the more likely she is to decide to leave the nest to bring in more food. Because the rate at which the foragers’ crop empties is tied to the amount of food in the receiving ants’ crops, how often the forager goes for food changes with the hunger level of the whole colony, with more trips when the ants are hungrier. These experiments show that the amount of food in the crops of the receiving and foraging ants helps foragers adapt their behavior to the colony’s needs. This mechanism means the insects can achieve a common goal without explicitly knowing it. However, it remains to be explained how exactly the mechanical changes in the fullness of foragers’ crop underpin this decision-making process.