Strangler fig is the common name for a number of tropical and subtropical plant species, including some banyans and unrelated vines, including among many other species.
All of these share a common "strangling" growth habit that is found in many tropical forest species, particularly of the genus Ficus. This growth habit is an adaptation for growing in dark forests where the competition for light is intense. These plants are hemiepiphytes, spending the first part of their life without rooting into the ground. Their seeds, often bird-dispersed, germinate in crevices atop other trees. These seedlings grow their roots downward and envelop the host tree while also growing upward to reach into the sunlight zone above the canopy
An original support tree can sometimes die, so that the strangler fig becomes a "columnar tree" with a hollow central core. However, it is also believed that the strangler fig can help the support tree survive storms.
Strangler trees are able to colonize the difficult building-wall habitat in urban areas. Strangler figs in the tropics are pre-adapted to adopt an aerophytic as well as acrobatic urban life by clinging onto building envelopes.
Source : Strangler Fig