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Abstract Anthropogenic changes are often studied in isolation but may interact to affect biodiversity. For example, climate change could exacerbate the impacts of biological invasions if climate change differentially affects invasive and native species. Behavioural plasticity may mitigate some of the impacts of climate change, but species vary in their degree of behavioural plasticity. In particular, invasive species may have greater behavioural plasticity than native species since plasticity helps invasive species establish and spread in new environments. This plasticity could make invasives better able to cope with climate change.Here our goal was to examine whether reproductive behaviours and behavioural plasticity vary between an introduced and a nativeOnthophagusdung beetle species in response to warming temperatures and how differences in behaviour influence offspring survival.Using a repeated measures design, we exposed small colonies of introducedO. taurusand nativeO. hecateto three temperature treatments, including a control, low warming and high warming treatment, and then measured reproductive behaviours, including the number, size and burial depth of brood balls. We reared offspring in their brood balls in developmental temperatures that matched those of the brood ball burial depth to quantify survival.We found that the introducedO. taurusproduced more brood balls and larger brood balls, and buried brood balls deeper than the nativeO. hecatein all treatments. However, the two species did not vary in the degree of behavioural plasticity in response to warming. Differences in reproductive behaviours did affect survival such that warming temperatures had a greater effect on survival of offspring of nativeO. hecatecompared to introducedO. taurus.Overall, our results suggest that differences in behaviour between native and introduced species are one mechanism through which climate change may exacerbate negative impacts of biological invasions.
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Higher heat acclimation ability in a non-native versus a native dung beetle (Onthophagus spp.)
Invasive species may be more capable of adjusting to climate warming via phenotypic plasticity than native species since plasticity is thought to increase invasion success. Physiological plasticity via acclimation is one way in which organisms can adjust their thermal tolerance in response to temperature change, but few studies have addressed whether invasive species have greater thermal plasticity compared to native congeners. Here we investigated whether thermal plasticity via temperature acclimation varies between two Onthophagus dung beetle species, the non-native Onthophagus taurus and the native Onthophagus hecate, collected from both Florida and Tennessee, USA. We expected the non-native O. taurus to demonstrate greater plasticity than the native O. hecate; we also predicted that beetles from Florida would have reduced plasticity since their environment is less thermally variable. To examine thermal plasticity, we measured shifts in time until loss of function (i.e., leg mobility) following acclimation to hot or cold temperature treatments. We found that non-native O. taurus from Florida acclimated to warm temperatures, increasing time to loss of function following warm treatments; unexpectedly, O. taurus from Tennessee showed no warm acclimation ability. Onthophagus hecate did not acclimate to warm temperatures in either location. In contrast, both species showed similar levels of cold acclimation. Taken together, our results suggest that the non-native species, O. taurus, will be more capable of using physiological adjustments to respond to climate warming than the native species, O. hecate.
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- Award ID(s):
- 1930829
- PAR ID:
- 10573363
- Publisher / Repository:
- Dryad
- Date Published:
- Subject(s) / Keyword(s):
- FOS: Biological sciences FOS: Biological sciences Dung beetles Thermal Plasticity thermal physiology Scarabaeinae
- Format(s):
- Medium: X Size: 43971 bytes
- Size(s):
- 43971 bytes
- Right(s):
- Creative Commons Zero v1.0 Universal
- Sponsoring Org:
- National Science Foundation
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