High genetic diversity is not essential for successful introduction

Area of Science:

• Ecology
• Evolutionary Biology
• Genetics

Background:

• Introduced species often adapt and evolve in new environments despite presumed loss of genetic diversity.
• Understanding genetic diversity retention is crucial for predicting invasion success and evolutionary potential.

Purpose of the Study:

• To quantify genetic diversity retained at introduction in two invasive plant species, Arctotheca populifolia and Petrorhagia nanteuilii.
• To assess the relationship between genetic diversity retention and adaptation in introduced populations.

Main Methods:

• Microsatellite data were used to analyze genetic diversity in native and introduced ranges of A. populifolia and P. nanteuilii.
• Genetic diversity in introduced populations was compared to native ranges and confamilial species from literature.
• Source populations for introductions were identified.

Main Results:

• Native gene diversity for both species was lower than for confamilial species.
• Introduced populations showing adaptation retained an average of 81% of native genetic diversity.
• P. nanteuilii showed increased genetic diversity in introduced populations, while A. populifolia retained only 1-14% in studied introductions.

Conclusions:

• Invasive species can adapt to new environments with surprisingly little neutral genetic diversity.
• Adaptation and invasion success are possible even from introductions founded by small numbers of individuals.
• Low native genetic diversity in studied species did not preclude adaptation and significant morphological change in introduced ranges.