01637nas a2200193   4500008004100000245009400041210006900135300001200204490000800216520100200224653006801226100001701294700001301311700001701324700001601341700001801357700001901375856004901394       2009                        eng d00aSimultaneous freeze tolerance and avoidance in individual fungus gnats, Exechia nugatoria0 aSimultaneous freeze tolerance and avoidance in individual fungus  a897-9020 v1793 aFreeze tolerance and freeze avoidance are typically described as mutually exclusive strategies for overwintering in animals. Here we show an insect species that combines both strategies. Individual fungus gnats, collected in Fairbanks, Alaska, display two freezing events when experimentally cooled and different rates of survival after each event (mean ± SEM: −31.5 ± 0.2°C, 70% survival and −50.7 ± 0.4°C, 0% survival). To determine which body compartments froze at each event, we dissected the abdomen from the head/thorax and cooled each part separately. There was a significant difference between temperature levels of abdominal freezing (−30.1 ± 1.1°C) and head/thorax freezing (−48.7 ± 1.3°C). We suggest that freezing is initially restricted to one body compartment by regional dehydration in the head/thorax that prevents inoculative freezing between the freeze-tolerant abdomen (71.0 ± 0.8% water) and the supercooled, freeze-sensitive head/thorax (46.6 ± 0.8% water).10aMycetophilidae · Exechia nugatoria · Supercooling · Exotherm1 aSformo, Todd1 aKohl, F.1 aMcIntyre, J.1 aKerr, Peter1 aDuman, J., G.1 aBarnes, B., M.  uhttps://sciaroidea.myspecies.info/node/43890