Wednesday, March 9, 2016

Temporal genetic structure in the introduced ascidian Styela plicata

by M.Carmen Pineda

It’s been almost three years since the last paper on Styela plicata was published by our group, but the saga is not over yet!! The article entitled “Stable populations in unstable habitats: temporal genetic structure of the introduced ascidian Styela plicata in North Carolina”, by M.Carmen Pineda, Xavier Turon, Rocio Perez-Portela and Susanna Lopez-Legentil, has been just published online in the journal Marine Biology.

The solitary ascidian Styela plicata.
Styela plicata is a solitary ascidian, which has been introduced by ship fouling to harbours and marinas around the globe. This species has been extensively studied during the last years, based on its potential to become a plague. However, this is the first time that its genetic composition is studied on a temporal scale. On this recent study, a combination of nuclear and mitochondrial markers (7 microsatellites and a fragment of the gene Cytochrome Oxidase subunit I, COI) were used to analyse the genetic composition of one population subjected to environmental fluctuations and periodical die-offs, every 2 months and over 2.5 years. Overall, our results indicate that the investigated population is stable over time and relies on a periodic arrival of larvae from other populations, maintaining high genetic diversity and a complex interplay of allele gains and losses.

Temporal analyses exploring genetic trends over time are a great tool to predict the likelihood of long time survival of an introduced population in a new habitat and its invasive potential. This kind of information is particularly relevant when deciding which introduced species are more detrimental, and should help resource managers to focus their control and eradication efforts.