this vegetation zone are also known to include thickets that are mainly composed of shrubby or woody vegetation, including species from the genera Ilex, Ageratina, and Baccharis. Fragmented forests can appear in the subpáramo due to microclimatic or edaphic conditions, yet the more abrupt changes are generally due to anthropogenic disruption such as cutting, burning, and grazing activities. Because of these high levels of disruption, it is believed that subpáramos are made up of largely secondary-growth communities. The high levels of disruption also make this zone particularly difficult to define, as humans typically extend and expand the zone for their own purposes, sometimes over hundreds or thousands of years. This has altered forest lines, often lowering them by several hundred meters, which has also affected the altitudinal zonation for many animals. Lichens are widely distributed in all types of paramos, however different growth forms may be favoured by environmental conditions. For example, extreme conditions associated with rocky substrates and high elevations favour crustose lichens, while foliose and fruticose lichens are associated with less extreme conditions and mid altitudes. The atmospheric factors such as humidity and temperature positively favour taller lichens, due to an increase in locally available water. Fauna The vegetation of the páramo provides shelter and habitat for a variety of mammals, birds, insects, amphibians, and reptiles. Some animals commonly found in páramo ecosystems include the Culpeo (sometimes called the páramo wolf), the white-tailed deer, and the spectacled bear (Tremarctos ornatus) which occasionally forages in the high páramo for its favored food, Puya bromeliads. Invertebrates such as grasshoppers, cockroaches, beetles, and flies are found in the subpáramo. Amphibians have been well documented in páramo ecosystems, including salamanders such as Bolitoglossa species and frogs such as Pristimantis and Atelopus species. Reptiles include lizards of the genera Stenocercus, Phenacosaurus, and Proctoporus. Sixty-nine species of birds are considered to be "total users" of páramo habitats, with "41 species making it their primary habitat and 16 as indicator species". The Andean condor (Vultur gryphus), also called "king of the Andes", is known for its wide wingspan, but is no longer frequently seen. The most numerous bird families in the páramo include eagles, hummingbirds, ovenbirds, thraupid "finches", and tyrant flycatchers. Some hummingbirds tolerate the cold climate by going into "a kind of nightly hibernation." Hummingbirds, bees and flies are all important pollinators in the páramo, while birds and smaller mammals such as rabbits and