By spreading their seeds over a wide area, plants make it more likely that some of their offspring will survive. Some seeds, such as dandelion seeds, are light and feathery and can sail on the breeze. Some seeds hitch-hike! When birds eat berries, the seeds in the fruit come out later in the bird's droppings - many miles away! Coconut trees have seeds that float. They can ride ocean currents over distances of 1,000 miles (1,600km) or more!