Masteroppgaver (MSc) i paleontologi ved Naturhistorisk museum

This page in English

Marine faunas in the Holocene of the Oslofjord area – climate, sea level, faunal invasion

Marine sediments of the Holocene (last 10,000 years) in the Oslofjord area are now widely exposed on land because of relative drop in sea level. These clays and sands are rich in well-preserved fossils of bivalves, gastropods and other invertebrates, recording dramatic changes in climate, sea level and ecology through time. These faunas have not been extensively studied for more than a hundred years (Brøgger 1901). Since then, our understanding of Holocene climate and ecology has increased enormously, and methods have vastly improved regarding e.g. radiocarbon dating, geochemistry for climate reconstruction, and ecological and stratigraphic data analysis.

We believe that the Holocene marine faunas in the Oslofjord area can provide a fruitful field of research into the ecology of environmental change. Since the taxa are the same as in our time, the Holocene data can be used as good analogues for modern processes, and possibly inform predictions about marine faunal responses to anthropogenic warming, sea level rise and faunal invasion such as that of the Pacific oyster.

We need several MSc students (biology or geology) to carry out a pilot study, giving you a unique opportunity to open up a new area of research. Old localities must be rediscovered, so some treasure hunting will be required! Projects include:

1. The Preboreal invertebrate faunas of the Oslofjord area

This project will focus on the first invertebrates to colonize the area after the ice cap receded, especially the bivalves, crustaceans and foraminifera near the so-called “marine limit”, i.e. the locally highest sea-level during deglaciation. What can the taxonomic composition of the faunas (often with Mytilus and barnacles), size distributions, sediment properties and geochemistry tell us about the early Holocene succession during rapid climatic warming and sea-level drop? The material will come from field work at localities around Oslo as well as from museum collections. The data will be used for ecological data analysis, especially ordinations and diversity analysis, and some biogeographical analysis and plotting (GIS).

2. The late Atlantic shallow-water oyster banks of the Oslofjord area

Throughout the Oslofjord area, mollusc faunas rich in oysters (“oyster banks”) are found ca. 10-40 meters above present sea level. Preliminary radiocarbon dating indicates that at least some of these are from late Atlantic time (ca. 4,000 BC), i.e. during the warm “climatic optimum” of the Holocene. The project will focus on the ecology of these oyster banks, with field and laboratory work. Possible localities include low-lying areas around Oslo (e.g. Slemmestad and Malmøya), and Hvaler ca. 100 km south of Oslo. Associated fossils will also be collected and identified for ecological data analysis. Are these oyster banks all of similar age, recording an event of regional significance? Do they represent a faunal invasion? We would also like to look at age distributions, shape variation etc. Encrusting and infestation (polychaete tubes and burrows, sponge borings, etc.) will be studied with microfocus CT.

3. Seawater paleotemperatures of the Holocene in the Oslofjord area

The student will attempt to estimate seawater temperatures using classical geochemical and paleoecological techniques applied to the fossil faunas. This will include oxygen isotope analysis (clumped isotopes may be attempted, depending on funding), Mg/Ca and Sr/Ca ratios, and comparing fossil assemblages with present-day faunas. We may also attempt reconstruction of paleosalinity using e.g. Ba/Ca ratios.

Kontaktperson: Øyvind Hammer

Paleoøkologi i Braksøyaformasjonen, silur, Oslofeltet

Koraller og svamper i Braksøyaformasjonen, Kapitelberget, Skien. Foto Sven Dahlgren

Braksøyaformasjonen er en meget fossilrik kalkstein som har vært tolket som fossile ”patch”-rev. Gode lokaliteter finnes bl.a. på Ringerike og ved Skien. Det har vært gjort en del taksonomiske arbeider på bl.a. koraller i denne formasjonen, og også sedimentologi, men hittil ingen økologiske studier hvor man tar for seg faunaen som helhet.

Oppgaven vil bestå i detaljert datainnsamling og kartlegging i felt, fotografering, preparering og identifisering, samt statistisk analyse med henblikk på artssammensetning og biodiversitet. Er det mulig å identifisere økologiske soner innenfor hver struktur (inter-rev, revfront, revtopp, lagune)? Hvordan er disse relatert til dyp, lys og energi? Kan det identifiseres suksesjoner, dvs. konsistente rekkefølger av av kolonisering? Finnes det trender på større skala (Ringerike-Porsgrunn)?

Oppgaven egner seg for en biologi- eller geologistudent med interesse for marinbiologi, økologi eller paleontologi.

Kontaktperson: Øyvind Hammer

Hydrostatikk og ontogenese hos endoceratider

Modell av endoceratid cephalopode, med utskjæring som viser septer og sifo. Ill: Øyvind Hammer

Blekkspruter med rett skall er viktige og vanlige fossiler, med mange beskrevne arter. Det har vært vanlig å forestille seg at disse svømte med skallet horisontalt, men det har nylig blitt klart at en vertikal orientering er mer sannsynlig hos en del former. Likevel tror vi fortsatt at bl.a. endoceratidene, som var vanlige i ordovicium, svømte horisontalt. Dette er basert på spesielle morfologiske trekk hos denne gruppen. Er dette korrekt? Hvilken rolle spilte opplagring av ”ballastmateriale” under veksten?

Oppgaven består i studier på fossilt materiale, og enkel matematisk modellering av balanse og oppdrift. Dette vil innebære noe programmering. Tilsvarende arbeid gjøres for øyeblikket for andre fossile cephalopoder av en gruppe i Sveits, og samarbeid med disse vil være naturlig.

Oppgaven egner seg for en biologi- eller geologistudent med litt interesse for matematikk.

Kontaktperson: Øyvind Hammer

Lokal veksthastighet i septer i ammonoideer – ontogenetiske og fylogenetiske konsekvenser

Modell av septe (kammerskillevegg) fra ammonitt. Ill: Øyvind Hammer

Ammonoideer er utdødde cephalopoder som betraktes som modellorganismer i studier av evolusjon, på grunn av stor artsrikdom, hurtig evolusjon og gode fossile data. Septene (kammerskilleveggene) er kompliserte, og følger interessante ontogenetiske og fylogenetiske trender.

Oppgaven består i preparering av fossiler, morfometrisk oppmåling (laserscanner eller koordinatmålemaskin), og beregning av lokal veksthastighet. Tolkning med henblikk på sammenhenger mellom ontogenese og fylogenese (heterokroni). Prosjektet vil kunne innebære samarbeid med en forskningsgruppe i Sveits.

Studenten bør ha noe bakgrunn i informatikk, og gjerne interesse for 3D datagrafikk.

Kontaktperson: Øyvind Hammer

”Geologiske” oppgaver

Syklostratigrafi i ordovicium, Oslofeltet

Fra mange steder i verden, og fra mange geologiske tidsperioder, er det nå beskrevet syklisitet i sedimentære bergarter som kan tilskrives astronomiske pådrag (Milankovitsj-sykler). Dette gir oss et uhyre kraftig stratigrafisk verktøy for datering og korrelasjon. Slike sykler har vært foreslått men aldri undersøkt for en del formasjoner i ordovicium i Oslofeltet (spesielt Vollenformasjonen).

Oppgaven vil bestå i visuell logging av vekslende skifer- og kalksteinslag i Oslo-området, og kjernemateriale fra Langesund-området. Dette kan eventuelt understøttes av geofysiske logger (magnetisk susceptibilitet) og geokjemi (karbonatinnhold). Påfølgende statistisk analyse vil innebære tidsserie-metoder som spektralanalyse og wavelet-analyse.

Kontaktperson: Øyvind Hammer

 

"Biologiske" oppgaver:

Grow fast reproduce fast? Life histories in the marine environment of Svalbard.

Life histories are amazingly varied among species. Some species live fast, reproduce early and die young while others mature slowly and produce few offspring that they invest heavily in to project. Life histories are also varied among individuals of the same species and this variation can be acted upon by selection. With rapid climate change, the life histories of organisms are subject to differential success. Despite the importance of benthic marine habitats to the health of marine environments in general and the vigor of fisheries, little is known about how life histories are impacted by variation in temperature and habitat.

In this project, a creative and hardworking master student will estimate the growths rates of encrusting bryozoan colonies using data collected over a decade from settlement panels in Svalbard. These panels, from two depths and several sites in Svalbard, representing a variety of environments had been photographed over 1 to 8 years and then air-dried. We will then model growth rates of these bryozoan species as a function of habitat (depth, community composition, coverage, site) and average temperature. There will also be an opportunity to estimate age of first reproduction and average reproductive allocation because bryozoans have easily observed ovicells that brood embryos.

Growth rates of marine bryozoans are little known and this study will greatly contribute to badly needed basic information on important life history traits (growth rates and average fecundity as measure by ovicell density) of key marine benthic organisms. It will also contribute to our knowledge on how life history traits may vary under different environmental conditions so we might be able to make predicts about the fate of marine benthic communities under climate change scenarios.

For instance, one hypothesis is that dynamic environments (shallow areas with more ice and wave action) promote life histories that are shorter (earlier maturation) and produce higher numbers of offspring than those from deeper and more stable habitats. Food availability is also highly seasonal in the Svalbard area and we might hypothesize that growth and reproduction should increase during pulses of nutrient input. But to what degree this happens and whether there is a time lag in response may vary across species and may also be modulated by habitat stability.

The successful student will learn about marine benthic ecology, life history evolution and acquire skills in statistical analysis using R and will likely travel to Sopot in Poland and may join in scientific diving in Svalbard. The student will be supervised by Lee Hsiang Liow (NHM Oslo), Kjetil Voje (CEES), and Piotr Kuklinksi (Polish Institute of Oceanology, Sopot).

Contact person: Lee Hsiang Liow 

 

Molecular phylogeny and trait evolution of adeonid bryozoans

Bryozoans are colonial animals that sometimes look superficially like corals but have zooids that are usually highly polymorphic. One particular group of marine bryozoans, the adeonids, are particularly noticeable to the casual snorkeler or diver because they form large colonies and live in relatively shallow waters. Despite being colourful, potentially invasive (e.g. Reptadeonella violacea), and having extremely large and unusual larva, adeonids are largely neglected and hence little understood by marine ecologists and evolutionary biologists. How did they evolve these very large larvae? Why do they need such fancy colors? They have very mean-looking defence zooids called avicularia, who/what are they fighting against?

Adeonella lichenoides from bryozoan.net, courtesy of D. P. Gordon (NIWA New Zealand). Notice the small avicularia and a single large avicularium in the middle of the Scanning Electrograph.

In this masters thesis, a hardworking, motivated and resourceful student will be using a combination of old-fashioned PCR and Sanger sequencing approaches and state-of-the-art genome skimming and Next-Generation-Sequencing techniques to elucidate the phylogeny of this large family of bryozoans. The living material will stem from international collaborators based in Italy, Scotland, New Zealand, Japan, Russia, Australia, South Africa, among others. Using these newly generated information from taxa that have never been sequenced, the student will reconstruct the phylogenetic history of adeonids.

Key questions that we will be able to answer in this project are the follow: 1) Is Adeonidae really a monophyletic family? 2) There are two types of frontal shields among the species of this family, umbonuloid and lepraliomorph. Did these shield types evolve just once or multiple times, and when? 3) What is the phylogenetic distribution of the different types of avicularia we see within the group and did exposure to new types of habitats in their evolutionary past promote the evolution of different avicularia?

The student will be supervised by Lee Hsiang Liow (NHM Oslo), Kjetil Voje (CEES), Russell Orr (Evogene), Andrea Waeschenbach (NHM, London) and Björn Berning (Linz Museum, Austria) and will learn about metazoan systematics, marine biology, evolutionary biology, sequencing techniques, scanning electron microscopy, phylogenetic reconstruction and statistical analyses.

Contact person: Lee Hsiang Liow 

 

Relevante paleontologiske kurs:

Relevante biologikurs:

Prøv også kurskatalogen for geofag og biofag dersom pekerne til de enkelte kursene ikke fungerer. Litt informasjon for skoleelever som vurderer en utdannelse innen geologi.

Publisert 30. jan. 2009 17:32 - Sist endret 16. sep. 2018 17:40