Because of climate change, many insect species are shifting their altitudinal and latitudinal ranges, including Mediterranean butterflies, particularly in mountainous regions. In this study, we evaluated changes in butterfly communities over time, sampled in 1975, 2004, and 2012, in relation to their altitude and two indices representing the climate envelopes of species within a given community: CTI (Community Temperature Index) and CPI (Community Precipitation Index). The study took place in a protected area where we found strong changes in community compositions over the 37-year study period. There was no vertical stratification of communities in 1975, but became significantly so in 2004 and 2012. Likewise, CTI and CPI were correlated with altitude only in 2004 and 2012. Over time, CTI increased at lower altitudes, indicating an increase in species associated with higher temperatures, and was stable or decreased at higher altitudes. CPI showed opposing trends, decreasing at lower altitude of communities and increasing in higher altitude communities. This resulted in asymmetric changes along the altitudinal gradient. The highest elevations (>1900 m) shifted towards butterfly species that are more associated with colder, wetter habitats, and lower elevations shifted towards species more associated with hotter, drier habitats. In conclusion, changes in butterfly communities were consistent with expectations from observed changes of temperatures and precipitations at low altitudes and mid-altitudes, but not at the highest altitudes. This counter-intuitive result may be due to land-use changes following creation of a national park in 1993 that encompassed the sample sites, but we lack the data to test this hypothesis.

由于气候变化，许多昆虫物种正在改变其海拔和纬度范围，包括地中海蝴蝶，特别是在山区。在这项研究中，我们评估了1975年，2004年和2012年采样的蝴蝶群落随时间的变化，这些变化与它们的海拔高度以及代表给定群落中物种的气候包膜的两个指数有关：CTI（群落温度指数）和CPI（社区降水指数）。这项研究是在一个保护区进行的，我们在37年的研究期内发现社区组成发生了重大变化。1975年，社区没有垂直分层，但在2004年和2012年变得如此明显。同样，CTI和CPI仅在2004年和2012年与海拔高度相关。表示与高温相关的物种增加，并且在更高的海拔高度稳定或下降。CPI呈现相反的趋势，在较低海拔的社区呈下降趋势，在较高海拔的社区呈上升趋势。这导致沿高度梯度的不对称变化。最高海拔（> 1900 m）偏向与更凉，更湿的栖息地相关的蝴蝶物种，较低海拔向偏偏与更热，更干燥的生境的物种相关。总之，蝴蝶群落的变化与低海拔和中海拔（而非最高海拔）观察到的温度和降水变化的预期一致。