TY - JOUR

T1 - Linking species thermal tolerance to elevational range shifts in upland dung beetles

AU - Birkett, Ali J.

AU - Blackburn, George Alan

AU - Menendez Martinez, Maria Rosa

N1 - This is the peer reviewed version of the following article: Birkett, A. J., Blackburn, G. A. and Menéndez, R. (2018), Linking species thermal tolerance to elevational range shifts in upland dung beetles . Ecography, 41: 1510-1519. doi:10.1111/ecog.03458 which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/ecog.03458/abstract This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.

PY - 2018/9

Y1 - 2018/9

N2 - Climate warming has been proposed as the main cause of the recent range shifts seen in many species. Although species’ thermal tolerances are thought to play a key role in determining responses to climate change, especially in ectotherms, empirical evidence is still limited. We investigate the connection between species’ thermal tolerances, elevational range and shifts in the lower elevational limit of dung beetle species (Coleoptera, Aphodiidea) in an upland region in the northwest of England. We measured thermal tolerances in the laboratory, and used current and historical distribution data to test specific hypotheses about the area’s three dominant species, particularly the species most likely to suffer from warming: Agollinus lapponum. We found marked differences between species in their minimum and maximum thermal tolerance and in their elevational range and patterns of abundance. Overall, differences in thermal limits among species matched the abundance patterns along the elevation gradient expected if distributions were constrained by climate. A. lapponum abundance increased with elevation and this species showed lower maximum and minimum thermal limits than Acrossus depressus, for which abundance declined with elevation. Consistent with lower tolerance to high temperature, we recorded an uphill retreat of the low elevation limit of A. lapponum (177 m over 57 years) in line with the increase in summer temperature observed in the region over the same period. Moreover, this species has been replaced at low and mid-elevations by the other two warm-tolerant species (A. depressus and Agrilinus ater). Our results provide empirical evidence that species’ thermal tolerance constrains elevational ranges and contributes to explain the observed responses to climate warming. A mechanistic understanding of how climate change directly affects species, such as the one presented here, will provide a robust base to inform predictions of how individual species and whole assemblages may change in the future.

AB - Climate warming has been proposed as the main cause of the recent range shifts seen in many species. Although species’ thermal tolerances are thought to play a key role in determining responses to climate change, especially in ectotherms, empirical evidence is still limited. We investigate the connection between species’ thermal tolerances, elevational range and shifts in the lower elevational limit of dung beetle species (Coleoptera, Aphodiidea) in an upland region in the northwest of England. We measured thermal tolerances in the laboratory, and used current and historical distribution data to test specific hypotheses about the area’s three dominant species, particularly the species most likely to suffer from warming: Agollinus lapponum. We found marked differences between species in their minimum and maximum thermal tolerance and in their elevational range and patterns of abundance. Overall, differences in thermal limits among species matched the abundance patterns along the elevation gradient expected if distributions were constrained by climate. A. lapponum abundance increased with elevation and this species showed lower maximum and minimum thermal limits than Acrossus depressus, for which abundance declined with elevation. Consistent with lower tolerance to high temperature, we recorded an uphill retreat of the low elevation limit of A. lapponum (177 m over 57 years) in line with the increase in summer temperature observed in the region over the same period. Moreover, this species has been replaced at low and mid-elevations by the other two warm-tolerant species (A. depressus and Agrilinus ater). Our results provide empirical evidence that species’ thermal tolerance constrains elevational ranges and contributes to explain the observed responses to climate warming. A mechanistic understanding of how climate change directly affects species, such as the one presented here, will provide a robust base to inform predictions of how individual species and whole assemblages may change in the future.

U2 - 10.1111/ecog.03458

DO - 10.1111/ecog.03458

M3 - Journal article

VL - 41

SP - 1510

EP - 1519

JO - Ecography

JF - Ecography

SN - 0906-7590

IS - 9

ER -