Elevation use over time
All bumblebees tested for elevation shift over time have significantly changed their altitude from a given year or time range. Bombus alpinus, mendax and mucidus have uplifted since the ‘80s and similarly B. konradini changed sometime between the 1960s and the 1980s considering that the data are unevenly distributed in time (Figure 2, Table 4). In B. alpinus, mendax and mucidus , the year of record was a significant predictor in the most recent time interval, but not in the older time interval and the slopes of the regression lines at both sides were significantly different (Table 4). In B. konradini , the records from the 60s were significantly different in elevation from the more recent year groups, which were not different from each other (Table 4). The estimated elevation uplift resulted large in all species, between ca 325 and 535 m, but it is important to note that occasional records were present also below the calculated elevation range and that the estimate changes depending on the chosen quartile (Supplementary table S3). Under future scenarios, the elevational shift is predicted to continue considerably, based on the distribution of the suitable patches (Supplementary table s4). Hypothesis H3 was therefore fully confirmed by the observed and predicted shifts.