These interactions can be facilitative or competitive.[5] Planting certain species together can protect one or both from extreme temperature fluctuations, drying out in the sun, harsh winds, and predators, in addition to improving soil composition. Competition can occur within or between species, and generally weaker individuals and weaker species die out, resulting in increased plant spacing.[5] Spatial arrangement of revegetation species also influences pollination and seed dispersal. For species whose seeds are wind-dispersed and animal-dispersed, plant diversity in seed dispersal range is important for genetic fitness.