Urbanization is creating a new global biome, in which cities and suburbs around the world often resemble each other more than the local natural areas they replaced. But while urbanization can profoundly affect ecology at local scales, we know little about whether it disrupts large-scale ecological patterns. Here we test whether urbanization disrupts a macroecological pattern central to ecological and evolutionary theory: the increase in seed predation intensity from high to low latitudes. Across 14,000 km of latitude spanning the Americas, we compared predation intensity on two species of standardized experimental seeds in urbanized and natural areas. In natural areas, predation on both seed species increased fivefold from high latitudes to the tropics, one of the strongest latitudinal gradients in species interactions documented so far. Surprisingly, latitudinal gradients in predation were equally strong in urbanized areas despite significant habitat modification. Nevertheless, urbanization did affect seed predation. Compared with natural areas, urbanization reduced overall predation and vertebrate predation, did not affect predation by invertebrates in general, and increased predation by ants. Our results show that macroecological patterns in predation intensity can persist in urbanized environments, even as urbanization alters the relative importance of predators and potentially the evolutionary trajectory of urban populations.

城市化正在创造一个新的全球生物群落，其中世界各地的城市和郊区往往比它们所取代的当地自然区域更相似。但是，尽管城市化可以在局部范围内对生态产生深远影响，但我们对它是否会破坏大规模的生态模式知之甚少。在这里，我们测试了城市化是否破坏了生态学和进化论的核心宏观生态模式：种子捕食强度从高纬度到低纬度的增加。在横跨美洲的 14,000 公里纬度上，我们比较了城市化和自然地区两种标准化实验种子的捕食强度。在自然区域，从高纬度到热带地区，对这两种种子物种的捕食增加了五倍，这是迄今为止记录的物种相互作用中最强的纬度梯度之一。令人惊讶的是，尽管栖息地发生了重大改变，但城市化地区捕食的纬度梯度同样强烈。尽管如此，城市化确实影响了种子捕食。与自然区域相比，城市化减少了整体捕食和脊椎动物捕食，总体上不影响无脊椎动物的捕食，增加了蚂蚁的捕食。我们的结果表明，捕食强度的宏观生态模式可以在城市化环境中持续存在，即使城市化改变了捕食者的相对重要性，并可能改变了城市种群的进化轨迹。