Climate change has different predicted effects on the range shifts of two hybridizing ambush bug (, Family , Order Hemiptera) species.

AIM

A universal attribute of species is that their distributions are limited by numerous factors that may be difficult to quantify. Furthermore, climate change-induced range shifts have been reported in many taxa, and understanding the implications of these shifts remains a priority and a challenge. Here, we use Maxent to predict current suitable habitat and to project future distributions of two closely related, parapatrically distributed species in light of anthropogenic climate change.

LOCATION

North America.

TAXON

Melin 1930 and Handlirsch 1897, Family: , Order: Hemiptera.

METHODS

We used the maximum entropy modeling software Maxent to identify environmental variables maintaining the distribution of two species, and . Species occurrence data were collected from museum databases, and environmental data were collected from WorldClim. Once we gathered distribution maps for both species, we created binary suitability maps of current distributions. To predict future distributions in 2050 and 2070, the same environmental variables were used, this time under four different representative concentration pathways: RCP2.6, RCP4.5, RCP6.0, and RCP8.5; as well, binary suitability maps of future distributions were also created. To visualize potential future hybridization, the degree of overlap between the two species was calculated.

RESULTS

The strongest predictor to ranges was the mean temperature of the warmest quarter, while precipitation of the driest month and mean temperature of the warmest quarter were strong predictors of ranges. Future ranges for are predicted to increase northwestward at higher CO concentrations. Suitable ranges for are predicted to decrease with slight fluctuations around range edges. There is an increase in overlapping ranges of the two species in all future predictions.

MAIN CONCLUSIONS

These evidences for different environmental requirements for and account for their distinct ranges. Because these species are ecologically similar and can hybridize, climate change has potentially important eco-evolutionary ramifications. Overall, our results are consistent with effects of climate change that are highly variable across species, geographic regions, and over time.