Quick Answer
The disappearance of all bees would create major ecological and agricultural disruption, especially for crops and wild plants that depend heavily on bee pollination. It would not eliminate all food because cereals such as wheat and rice are primarily wind-pollinated, and other pollinators would remain. Over time, however, plant reproduction, food diversity and ecosystem structure would change substantially.
Bees are among the most important pollinators, but pollination is a network rather than a single-species service. Butterflies, moths, flies, beetles, birds, bats and wind all move pollen between plants. The consequences of losing bees therefore depend on which plants rely on them and how much alternative pollination exists.
Food would not disappear overnight
Many staple crops are not dependent on bees for pollination. Wheat, rice and maize primarily use wind or self-pollination. Fruits, nuts and many vegetables, however, can depend strongly on animal pollinators, with the importance varying by crop and farming system.
The biggest agricultural shock
Crops that rely heavily on bee pollination could become more expensive, less productive or more labor-intensive. Farmers could attempt manual pollination or manage alternative pollinators, but doing this at the scale of global agriculture would be difficult and costly.
Wild ecosystems would change too
Wild plants also need reproduction. If bee-dependent plants produced fewer seeds, their abundance could decline. That would alter food availability for insects, birds and mammals and could cascade through ecosystems over multiple generations.
Established scienceThe phrase 'bees pollinate all our food' is misleading. Bees are extremely important, but a large share of staple calories comes from wind-pollinated or self-pollinated crops.
Could another insect replace bees?
Some pollination could be compensated by other species, especially where flowers are generalist and accessible to many insects. But ecological networks are specialized in many places. A replacement would not necessarily reproduce the exact timing, behavior and geographic coverage of bees.
The long-term result
Human diets would likely become less diverse and more expensive in some regions, while natural plant communities reorganized. The biggest effects would be distributed unevenly: crops with strong dependence on bee pollination would face much larger disruption than crops that do not need animal pollinators.
Mostly not bee-dependent
Staple grains
Often strongly pollinator-dependent
Fruit & nuts
Reproduction disrupted
Wild plants
Partial, not perfect
Replacement pollinators
The bottom line
Losing all bees would be a major ecological and agricultural shock, not an instant end to human food. The deeper consequence would be the loss of a huge part of the pollination network that supports both farms and wild ecosystems.