PROGRESSIVE REDUCTION IN THE MEAN BODY SIZES OF SOLITARY BEES ACTIVE DURING THE FLOWERING SEASON AND ITS CORRELATION WITH THE SIZES OF BEE FLOWERS OF THE MINT FAMILY (LAMIACEAE)

ABSTRACT

We investigated the body size of solitary bee species in a Mediterranean plant community of Israel in relation to the seasonal increase in air temperature during the flowering season. We found that the body sizes of the species of solitary bees that are active from March to August are negatively correlated with the seasonal increase in air temperature. Also, the seasonal decrease in the body sizes of bees is correlated with a progressive decrease in the flower sizes of bee-pollinated species of the mint family that blossom each month.