BOTANY

Detailed explanation-1: -Pollination by insects is a much more reliable and efficient pollination mechanism than chance dispersal. Pollination by insects determines plant community structures. Pollination by insects is particularly important for Australian native trees and shrubs.

Detailed explanation-2: -Flowering plants have evolved two pollination methods: 1) pollination without the involvement of organisms (abiotic), and 2) pollination mediated by animals (biotic). About 80% of all plant pollination is by animals. The remaining 20% of abiotically pollinated species is 98% by wind and 2% by water.

Detailed explanation-3: -Pollination, which occurs through the means of animals, is known as zoophily.

Detailed explanation-4: -Cross-pollination is a type of pollination in which pollen grains come from another plant. Cross-pollination is preferred because it brings about variation in species.