British species that are present in Australia have different traits from British species that are not present in Australia

Abstract

AbstractAimIntroduced species spreading to natural ecosystems is a leading cause of environmental change and a key feature of the Anthropocene. While there have been many studies of the traits of introduced and invasive species, less is known about the traits that affect a species' chances of reaching and establishing in new areas. We asked whether British species that are present in Australia have different traits to British species that are not present in Australia.LocationGreat Britain and Australia.MethodsWe compiled a list of all vascular plant species from Great Britain and divided them into those that are present in Australia (395 species) and those that are not present in Australia (1171 species). We compiled data for each species' seed mass, seedbank longevity, maximum plant height, flower size, flower colour and geographical extent in the British Isles. We conducted independent sample t‐tests for continuous variables and Chi‐squared tests for categorical variables to determine differences between groups.ResultsWe found British species present in Australia have, on average, larger geographic extents in the British Isles, longer periods of seed bank longevity (mean ~3 months as opposed to ~3 weeks), and maximum heights that are on average 36% taller than British species that are not present in Australia. However, British species present in Australia did not have significantly different flower size, flower colour or seed mass from British species that are not present in Australia.Main ConclusionsBritish species that are present in Australia and British species that are not present in Australia differ in several traits. These differences likely result from a combination of factors including introduction biases, environmental filters during establishment and stochasticity. Our results suggest that humans may be consciously and unconsciously selecting species for introduction. Some of the traits that are associated with an increased chance of a species being transported to/establishing in a new range also contribute to invasiveness. Thus, anthropogenic introduction biases could contribute to an increased risk of ecosystem invasion.