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On rangelands worldwide, cattle interact with many forms of biodiversity, most visibly with other large herbivores that share similar diets. Since 1995, we have been manipulating the presence and absence of cattle, medium-sized herbivores, and mega-herbivores (elephants and giraffes) in a series of large 4ha (10-acre) plots at the Kenya Long-term Exclosure Experiment (KLEE). These exclosures simulate different land management strategies. One of our goals is to disentangle the complex relationships between livestock and wildlife in a biome where worldwide, uneasy coexistence is the norm. We and our collaborators have shown that cattle have a wide variety of cascading effects on soils, hydrology, trees, grasses, herbs, microbes, insects, birds, reptiles, rodents, carnivores, and wild ungulates. 1) Cattle reduce habitat use across a broad array of ungulates, from grazers to browsers. 2) Conversely, wildlife often reduce (but sometimes facilitate) cattle weight gain. In particular, wildlife, being very responsive to fire, can greatly reduce the benefits of fire for cattle. 3) The trade-offs between cattle and (larger) wildlife are likely strongly buffered by compensatory responses of both elephants and smaller herbivores, especially rodents. 4) The absence of domestic and/or wild ungulates increases not only native rodents, but also their associated ticks and fleas, and the pathogens they carry. Conversely, dipped cattle act as ‘sweepers' of ticks, greatly reducing tick numbers on the landscape scale. 5) Cattle help maintain a diverse plant community whose composition remains more stable in the face of drought than when cattle are absent. In summary, the relationships between cattle and native biodiversity are complex, and include competitive, facilitative, and compensatory responses.