How do animals help spread seeds of Poaceae grasses?

Animals play a significant role in the dispersal of Poaceae (grass) seeds through two primary methods:

• Epizoochory (External transport): Many grasses have evolved specialized structures on their spikelets, such as awns (bristlelike projections), hairs, spines, barbs, and hooks. These features allow the seeds to catch onto the fur of passing animals, effectively hitchhiking to new locations. A notable example is the genus Cenchrus, commonly known as sandburs, which possess barbed spines that cling to animal fur or attach to the feet of humans.1

• Endozoochory (Internal transport): Large grazing animals, birds, and small mammals consume grass seeds as part of their diet. These seeds are then dispersed when they pass through the animal's digestive tract and are deposited in new areas.1

These adaptations ensure that grasses can colonize new habitats and maintain their distribution across diverse environments.1