Although slight changes in water level affect many species, the system as a whole also cycles and pulses with each change. Some transformations to the diversity of plant and animal life are natural, caused by fire or storms, and some are induced by humans, such as urban encroachment, the introduction of exotic species, and rapid global warming. Environmental conditions in the Everglades favor no particular species. Some species, such as snail kites and apple snails, do well in wet conditions, but wood storks and Cape Sable seaside sparrows (Ammodramus maritimus mirabilis) do well in dryer circumstances.[83]