Distributions and/or abundances of most species have been altered by human activities: most changes can be
attributed to habitat loss or to habitat alteration. However, in a few cases, shifts in distribution are explained more parsimoniously by a correlation with a recent climatic trend, especially when the shift has been either towards
the poles or upwards in elevation. Not unexpectedly, most of these examples are species (such as alpine and arctic
plants) whose distributions are most obviously limited by locations in maritime Antarctica, both species have shown dramatic increases in numbers from 1964–1990 as a result of greater seed germination and seedling survival.