... Dr. Dan Shapiro for creating a video of work I did in the summer of 1998. I am also grateful ... more ... Dr. Dan Shapiro for creating a video of work I did in the summer of 1998. I am also grateful to Dr. Derek Hagman, Gonzalo Arcila, Don Brewer, Dr. Drew Harvell, Shauna Slingsby, Dr. Charles Shaw, Kate Robinhawk, Dr. Jerry Brand, ...
Alpine treelines are expected to shift upward due to recent climate change. However, interpretati... more Alpine treelines are expected to shift upward due to recent climate change. However, interpretation of changes in montane systems has been problematic because effects of climate change are frequently confounded with those of land use changes. The eastern Himalaya, particularly Langtang National Park, Central Nepal, has been relatively undisturbed for centuries and thus presents an opportunity for studying climate change impacts on alpine treeline uncontaminated by potential confounding factors. We studied two dominant species, Abies spectabilis (AS) and Rhododendron campanulatum (RC), above and below the treeline on two mountains. We constructed 13 transects, each spanning up to 400 m in elevation, in which we recorded height and state (dead or alive) of all trees, as well as slope, aspect, canopy density, and measures of anthropogenic and animal disturbance. All size classes of RC plants had lower mortality above treeline than below it, and young RC plants (<2 m tall) were at hi...
Studies of heat shock response show a correlation with local climate, although this is more often... more Studies of heat shock response show a correlation with local climate, although this is more often across altitudinal than latitudinal gradients. In the present study, differences in constitutive but not inducible components of heat shock response are detected among populations of the Glanville fritillary butterfly Melitaea cinxia L. that exist at the species' latitudinal range limits (Finland and Spain). The study demonstrates that macroclimatic differences between these sites should cause greater exposure of the Spanish population to higher temperatures. Thermal stress treatments are used to estimate differences in the expression of four genes potentially relevant for tolerating these temperatures. For the analysis, three heat‐shock proteins and glyceraldehyde‐3‐phosphate dehydrogenase (G3PDH), a glycolysis enzyme that also modulates cell growth based on metabolic state, are chosen. Two constitutive differences are found between the sites. First, insects from Spain have higher ...
Insect movement: mechanisms and consequences. Proceedings of the Royal Entomological Society's 20th Symposium, London, UK, September 1999
This paper shows first how insect range shifts have tracked climate change over geological time, ... more This paper shows first how insect range shifts have tracked climate change over geological time, then over historical time, and finally over this past century. Much of this paper is focused on how recent range shifts have been studied in the light of responses to current global warming trends. Evidence is presented that infrequent, single extreme weather and climate events, as opposed to mean climatic trends, may be principal drivers of such range movements.
... Dr. Dan Shapiro for creating a video of work I did in the summer of 1998. I am also grateful ... more ... Dr. Dan Shapiro for creating a video of work I did in the summer of 1998. I am also grateful to Dr. Derek Hagman, Gonzalo Arcila, Don Brewer, Dr. Drew Harvell, Shauna Slingsby, Dr. Charles Shaw, Kate Robinhawk, Dr. Jerry Brand, ...
Alpine treelines are expected to shift upward due to recent climate change. However, interpretati... more Alpine treelines are expected to shift upward due to recent climate change. However, interpretation of changes in montane systems has been problematic because effects of climate change are frequently confounded with those of land use changes. The eastern Himalaya, particularly Langtang National Park, Central Nepal, has been relatively undisturbed for centuries and thus presents an opportunity for studying climate change impacts on alpine treeline uncontaminated by potential confounding factors. We studied two dominant species, Abies spectabilis (AS) and Rhododendron campanulatum (RC), above and below the treeline on two mountains. We constructed 13 transects, each spanning up to 400 m in elevation, in which we recorded height and state (dead or alive) of all trees, as well as slope, aspect, canopy density, and measures of anthropogenic and animal disturbance. All size classes of RC plants had lower mortality above treeline than below it, and young RC plants (<2 m tall) were at hi...
Studies of heat shock response show a correlation with local climate, although this is more often... more Studies of heat shock response show a correlation with local climate, although this is more often across altitudinal than latitudinal gradients. In the present study, differences in constitutive but not inducible components of heat shock response are detected among populations of the Glanville fritillary butterfly Melitaea cinxia L. that exist at the species' latitudinal range limits (Finland and Spain). The study demonstrates that macroclimatic differences between these sites should cause greater exposure of the Spanish population to higher temperatures. Thermal stress treatments are used to estimate differences in the expression of four genes potentially relevant for tolerating these temperatures. For the analysis, three heat‐shock proteins and glyceraldehyde‐3‐phosphate dehydrogenase (G3PDH), a glycolysis enzyme that also modulates cell growth based on metabolic state, are chosen. Two constitutive differences are found between the sites. First, insects from Spain have higher ...
Insect movement: mechanisms and consequences. Proceedings of the Royal Entomological Society's 20th Symposium, London, UK, September 1999
This paper shows first how insect range shifts have tracked climate change over geological time, ... more This paper shows first how insect range shifts have tracked climate change over geological time, then over historical time, and finally over this past century. Much of this paper is focused on how recent range shifts have been studied in the light of responses to current global warming trends. Evidence is presented that infrequent, single extreme weather and climate events, as opposed to mean climatic trends, may be principal drivers of such range movements.
Uploads