Background Phylogenetic and population genetic studies often deal with multiple sequence
alignments that require manipulation or processing steps such as sequence concatenation …

Echiura (commonly called spoon worms) are derived annelids that have an unsegmented
sausage-shaped body with a highly extensible anterior end (ie a proboscis). Echiura …

Darwin [1] hypothesized that sexes in a species should be similar unless sexual selection,
fecundity selection, or resource partitioning has driven them apart. Male dwarfism has …

Dead coral rocks are prevalent hard substrates in shallow warm waters, providing habitat for
various infaunal and boring invertebrates. Despite this, the nature of species interactions …

Echiurans (spoon worms) are derived annelids that have secondarily lost segmentation.
Recently, two molecular phylogenetic studies were performed to resolve the interfamily …

A sexual system is the pattern of gender allocation that characterizes a species. In both
plants and animals, simultaneous hermaphroditism and dioecy are the most common and …

Polar ecosystems are considered very fragile, however, due to the short observation record
it is hard to assess the recovery processes of the coastal and fjord environments after a …

Known as shovel head worms, members of Magelonidae comprise a group of polychaetes
readily recognised by the uniquely shaped, dorso-ventrally flattened prostomium and paired …

Echiurans (spoon worms) are marine invertebrates that have a sausage-shaped
unsegmented body with an extensible spoon-like proboscis. Most species live inside …

The larval segment formation and secondary loss in echiurans is a special phenomenon,
which is considered to be one of the important characteristics in the evolutionary relationship …