Invasiveness of alien plants in Brussels is related to their phylogenetic similarity to native species

Aim Understanding the processes that drive invasion success of alien species has
received considerable attention in current ecological research. From an
evolutionary point of view, many studies have shown that the phylogenetic
similarity between the invader species and the members of the native community
may be an important aspect of invasiveness. In this study, using a coarse-scale
systematic sampling grid of 1 km2, we explore whether the occupancy frequency
of two groups of alien species, archaeophytes and neophytes, in the urban
angiosperm flora of Brussels is influenced by their phylogenetic relatedness to
native species.
Location The city of Brussels (Belgium).
Methods We used ordinary least-squares regressions and quantile regressions for
analysing the relationship between the occupancy frequency of alien species in the
sampled grid and their phylogenetic distance to the native species pool.
Results Alien species with high occupancy frequency in the sampled grid are, on
average, more phylogenetically related to native species than are less frequent
aliens, although this relationship is significant only for archaeophytes. In addition,
as shown by the quantile regressions, the relationship between phylogenetic
relatedness to the native flora and occupancy frequency is much stronger for the
most frequent aliens than for rare aliens.
Main conclusions Our data suggest that it is unlikely that species with very low
phylogenetic relatedness to natives will become successful invaders with very high
distribution in the area studied. To the contrary, under future climate warming
scenarios, present-day urban aliens of high occupancy frequency are likely to
become successful invaders even outside urban areas.

Publication year:2010

Keywords:Archaeophytes, biological invasions, neophytes, phylogenetic distance, quantile regression, randomization