Pollen DNA barcoding networks which are made up of all the interactions between plants and the animals that facilitate their pollination. Identifying the pollen carried on insects helps scientists understand what plants are being visited by which insects. Insects can also have homologous features making them difficult to identify and are themselves sometimes identified through genetic barcoding (usually of the CO1 region). Every insect that visits a flower isn’t necessarily a pollinator. Many lack features such as hairs allowing them to carry pollen while others avoid the pollen-laden anthers to steal nectar. Pollination networks are made more accurate by including what pollen is
Pollen (microsporocyte, pollen mother cell or meiocyte), after meiotic division. After the formation of the four microspores, which are contained by callose walls, the development of the pollen grain walls begins. The callose wall is broken down by an enzyme called callase and the freed pollen grains grow in size and develop their characteristic shape and form a resistant outer wall called the exine and an inner wall called the intine. The exine is what is preserved in the fossil record. Two basic types of microsporogenesis are recognised, simultaneous and successive. In simultaneous microsporogenesis meiotic steps I and II are completed