The colonial tunicate Didemnum perlucidum has been identified from numerous tropical and temperate locations worldwide, but its native and introduced ranges remain largely unknown. In Australia, D. perlucidum is listed as a target species under the introduced marine pest national monitoring network. In order to investigate the introduced status and potential routes of introduction and dispersal...

Anthropogenic activities frequently result in both rapidly changing environments and translocation of species from their native ranges (i.e., biological invasions). Empirical studies suggest that many factors associated with these changes can lead to complex genetic patterns, particularly among invasive populations. However, genetic complexities and factors responsible for them remain uncharact...

In recent years, new analytical tools have allowed researchers to extract historical information contained in molecular data, which has fundamentally transformed our understanding of processes ruling biological invasions. However, the use of these new analytical tools has been largely restricted to studies of terrestrial organisms despite the growing recognition that the sea contains ecosystems...

Ascidians or sea squirts form a diverse group within chordates, which includes a few thousand members of marine sessile filter-feeding animals. Their mitochondrial genomes are characterized by particularly high evolutionary rates and rampant gene rearrangements. This extreme variability complicates standard polymerase chain reaction (PCR) based techniques for molecular characterization studies,...

Human-induced global warming and species introductions are rapidly altering the composition and functioning of Earth's marine ecosystems. Ascidians (Phylum Chordata, Subphylum Tunicata, Class Ascidiacea) are likely to play an increasingly greater role in marine communities. The colonial ascidian B. schlosseri is a cryptic species complex comprising five genetically divergent clades (A-E). Clade...

Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ec...

Ascidians (invertebrate chordates) are very abundant in many marine subtidal areas. They often live in dense multispecies clumps; thus, interspecific competition for space may be intense. Although most noncolonial species are broadcast spawners, their eggs can be fertilized only by sperm of the same species (1). Multiple fertilization is lethal and all animals have evolved blocks to polyspermy....

C11 cyclopentenone, 5-hydroxy-7-prop-2-en(E)-ylidene-7,7a-dihydro-2H-cyclopenta[b] pyran-6-one, isolated earlier from the sponges and ascidians, is known as a natural product possessing antimicrobial and cytotoxic properties. However, its cancer preventive activity has not been studied. Cancer preventive and proapoptotic properties of the compound as well as its effect on the main MitogenActiva...