It is estimated that animal - or insect-pollinated plants produce 1000 pollen grains for each ovule; wind-pollinated plants produce 1,000,000 pollen grains for each ovule. What does that indicate about pollination systems

The plants which use animal or insects as pollination vector produce less pollen compared to the wind-pollinated plants.

This could be due to the reason that the chances of pollination by wind are less than the pollination by the animal or vectors.

The chances of pollination in animal pollination are high as the animals to feed on the useful product of plant will go to the other plants but in wind pollination, the chances are less as it depends on the speed and direction of the wind.

Thus, wind-pollinated plants produce high number of pollens.