Warming speeds up range expansion in an experimental model system

Dispersal is becoming increasingly critical to understand as climate change is forcing species to shift their ranges to track changing environments. While we know that warmer temperatures can prompt range shifts, there is little known about how temperature influences the capacity for organisms to move by changing rates of range expansion. Warmer temperatures could affect the range expansion rate through two pathways: by increasing random, density-independent movement via increased metabolic rates, and/or by increasing population growth rates and driving density-dependent movement. Surprisingly, there have been no experimental tests of the effect of temperature on range expansion rate. We used red flour beetles, Tribolium castaneum, to test the overall effect of temperature on the rate of range expansion and to determine if random movement, population density, or both could be driving this effect. We grew beetle populations in linear connected landscapes at three temperatures (27.5 ..., Main experiment
We tested the effect of temperature on the rate of range expansion in Tribolium castaneum flour beetles across experimental linear landscapes in three temperature treatments. Landscapes were made up of 12 acrylic boxes (4 cm x 4 cm x 6 cm), where each box represented an individual habitat patch. We filled each patch with 30 g of a mix of a high-quality and a low-quality resource for this species (60 % whole wheat flour and 40 % rice flour). We used this mixed flour medium in order to temper population growth and make tracking population sizes logistically feasible. Patches were arranged in a single row and held together with elastic bands. Each patch had a 2-mm diameter hole drilled beneath the flour level on each side to allow for dispersal between patches.
We established ten replicate landscapes at each of three temperatures: 27.5 °C, 30 °C, and 32.5 °C. The historic temperature of our laboratory strain was 30C and the thermal optimum for this species is 30-31 °C...., # Data for: The effect of temperature on the rate of range expansion

Dataset DOI: [10.5061/dryad.gf1vhhn0v](10.5061/dryad.gf1vhhn0v)

## Description of the data and file structure

There is one included spreadsheet, Breslin_and_Grainger_Dryad_Data.xlsx, that contains all data. A sheet called 'metadata' gives variable definitions to all three other sheets.

| main\_experiment | <br /> |
| :---------------------- | :--------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| column | explanation |
| count | coun...,