Introduction
Considering animals most people think about vertebrates and thereby especially mammals and birds. These are often considered the most sophisticated and evolutionary successful animals on Earth. However, this is not true taking into account evolutionary history, biodiversity, ecology or biomass. Invertebrates outshine vertebrates in all these categories. Moreover, invertebrates have evolved novel structures and inhabited habitats unoccupied by vertebrates. Hence, invertebrates have much to teach us about evolution in general and in particular. On the other hand, except for a few flagship species and groups, invertebrates are heavily understudied, especially considering marine invertebrates. The latter is especially important as all animals live depends on water and originated from the marine realm. Hence, understanding the evolution of marine invertebrates will help us to understand evolution at much more detailed and complete level.
The topic of this thesis will build upon the results of the ArtsDatabanken-project “Biodiversity in the marine algae belt”. The marine algae belt comprising kelp forests, seagrass meadows and rocky reefs with coralline red seaweeds is one of the most active primary producing environments in the sea. It also harbors a great diversity of animals including sea squirts, ribbon worms, nick worms, serpulid worms, spionid worms and skeleton shrimps. The species of these groups occupy important ecological functions as herbivores, predators and filter feeding organisms and can be sessile or agile as well as solitary or colonial. Globally these taxa comprise more than 7,000 species with around 250 species documented from Norwegian waters. This is why we conducted a field inventory and collected species of these taxa in Norway (from the Skagerrak up to Troms?). With morphological and molecular methods, we determined species and learned more about their distribution and their association with Norwegian nature types. These efforts resulted into the record of 624 collection samples with 944 specimens of 73 species from these animal groups and 43 localities in Viken, Tr?ndelag, Vestland, and Troms og Finnmark comprising 19 Norwegian nature types. Our results show that we have found 3 species and 1 subspecies, which are new to Norway, and at least 10, which are new to science, but there may be 7 additional ones. However, the first analyses concerning the new species also showed that much more detailed studies on these are necessary. This is where this Master project will work on.
Annelida (segmented worms) is a species-rich group with >20,000 species occurring in all habitats on Earth. In the three targeted habitats many different annelid families are found ranging from filter-feeding species to predators and these occupy different positions in the food webs of these habitats. Herein, we concentrated on the family Serpulidae (e.g., the serpulids Serpula, Hydroides, Spirorbis). Serpulidae are filter-feeding organisms living throughout their life in the same calcareous tube attached to different habitats such kelp leaves. Some serpulid species are known as very successful invasive species, which might cause substantial economic losses due to biofouling.
We found 16 species and 1 subspecies with about 270 specimens. Specimens of species complex Spirobranchus triqueter (trekantorm in Norwegian) was found very often both with respect to number of specimens as well as within different nature types. As Norwegian common name shows it is very well known to general public as it can be seen almost everywhere at the Norwegian shoreline. Spirobranchus triqueter is a generally widely distributed species across the European coastline from Northern Norway to the Mediterranean Sea. However, the molecular analyses revealed the morphological S. triqueter is a species complex and comprises at least two additional species in Norway alone. In the preliminary molecular tree of our data, the specimens of S. triqueter form three clearly distinct groups. However, the genetic distance between the groups is often not as pronounced as might be expected. Hence, a detailed taxonomic revision is required for these three clades to reveal if they show morphological differences after all, if the two closely related clades are truly two separate species, which shall be confirmed by other molecular markers as well as which of the three clades is S. triqueter and which ones are new one species. For the latter, sequence data from the type specimen or locality have to be obtained. However, as this species was described by Linne both might be not present and hence detailed morphological comparisons to the original description are necessary to determine the clade containing the name bearer as well as additional taxonomic actions as the assignment of a neotype. In your thesis, you obtain additional molecular data for new markers and specimens, as well as conduct detailed morphological studies using different forms of microscopy. You will compare your data with the publicly available data and literature and conduct a taxonomic revision of the species in Norwegian waters.
What you will learn:
You will learn to conduct taxonomic identification, extensive literature research and distribution mapping. This will include among others molecular barcoding and microscopy. You will apply programs for phylogenetic reconstruction and conduct statistical analyses of your results.
What we offer:
First and foremost, we offer a friendly and kind mentoring environment. We offer a membership in ForBio (the research school in biosystematics) where you will be able to take courses in several places in Norway. You will potentially be able to attend international courses if they fit with the objectives. You will be able to participate in a national conference (ForBio meeting) and potentially in an international conference depending on funding. If you are interested, we will be able to discuss travel opportunities and a travelling period abroad.
What we expect from you:
Commitment and dedication
Outcomes:
One (or more) scientific publications, conference communication
Supervision and teaching:
You will be supervised by Torsten Struck, Ana Teresa Capucho and Samaneh Pazoki (all UiO).
For further inquiries, please contact Torsten Struck (t.h.struck@nhm.uio.no)