EVOLUTIONARY BIODIVERSITY AND ECOLOGY
CODENET is a research network of eight European geological and marine
teams, funded by the EC Training and Mobility of Researchers programme
to carry out an integrated multidisciplinary study of six
species. The TMR funding runs from January 1998 to September 2001, it
support for post doctoral researchers in most groups plus network
and a contribution toward research costs.
NHM - The Natural History Museum, London
Key Participants: Jeremy R. Young, Markus Geisen, Franco Novarino, Paul
Main research areas: Microevolution and physiology of three of the key
species. Phylogeny and biomineralisation across the group.
ETHZ - Eidgenössische Technische Hochschule, Zürich -
Key Participants: Prof Hans Thierstein, Patrick Quinn, Sabrina Renaud
(now at U. Lyon), Christine Klaas (now at Chicago University),
Main research areas: Microevolution, ecology and palaeoecology of
leptoporus and Gephyrocapsa, development of online species database (EMIDAS)
VUA - Vrije Universiteit Amsterdam - Earth Sciences
Key Participants: Prof. Jan van Hinte, Gerald Ganssen, Patrizia Ziveri, Annelies Kleijne,
Peter Westbroek (Leiden)
Main research areas: Sediment trap studies, coccolith stable isotopes, and study of the biogeography
of Helicosphaera carteri, Syracosphaera pulchra and
U. Caen - Universite de Caen Basse-Normandie - Marine Biology
and Biotechnology Lab.
Key Participants: Prof. Chantal Billard, Prof. Jacqueline Fresnel, Ian
Probert, Aude Houdan.
Main research areas: Culture isolation and maintenance, life-cycle
and TEM fine structural study.
AWI - Alfred-Wegener-Institute for Polar & Marine Research,
Key Participants: Linda Medlin, Alberto Saez, Volker Huss
Main research areas: Molecular genetics - including evaluation of large
scale phylogeny, intraspecific genetic differentation and special study
of the plastid genome size.
CSIC - Consejo Superior de Investigaciones Cientificias -
de Ciencias del Mar
Key Participants: Prof. Marta Estrada, Kees van Lening, Joan Grimalt
Mikel Latasa, Lluisa Cros, Ramon Margalef.
Main research areas: Cruise-based study of biogeography and ecology of
the species. Biochemical studies of their photosynthetic pigments.
MNHN-UL - Museu Nacional de Historia Natural da Universidade
Key Participants: Mario Cachão, Anabela Olivera (UCTRA), Maria
Maria da Graca Vilarinho (IPIMAR), Alexandra Duarte Silva.
Main research areas: biogeographic and ecological study focussed on the
Portuguese shelf. Detailed study of intraspecific variation and
in the species Coccolithus pelagicus.
NIOZ - Nederlands Instituut voor Onderzoek der Zee
Key Participants: Jaap Sinninghe Daamsté, Hanno Kinkel, Gerard
Main research areas: Lipid biochemistry and biogeochemistry of the
species. Identification of holococcolith-heterococcolith life-cycle pairings
OTHER PARTICIPANTS: In addition to the core funded teams
several other groups are actively collaborating in the project in various ways
U. Bremen - Universität Bremen
Key Participants: Karl-Heinz Baumann, Claudia Sprengel, Babette Boeckel
Main research areas: Morphometric study of intraspecific variaton in
the CODENET species in plankton, sedment trap and geological samples;
U. Oviedo - University of Oviedo
Other collaborators include teams in: Bristol University,
Erlangen-Nürnberg, Ruhr-Universität Bochum, Università
degli studi di Milano, Università degli studi di Firenze,
University College London
Key Participant: Heather Stoll
Main research area: Study of Sr/Ca ratios in coccolith calcite, development and testing of this novel palaeoproxy
Coccolithophorids are one of the main open ocean primary producers, they
play key roles in the global carbon, carbonate and sulphur cycles. Their
coccoliths are the single most important component of deep-sea oozes and
chalks and provide key floral, isotopic, and biomarker signals for
global change in the geological record. Their exceptional fossil record
makes them an outstanding biostratigraphic group and gives them unusual
potential for testing evolutionary hypotheses. So they are being actively
studied by a wide range of research groups. This convergence of
formed the basis for the Global Emiliania Modelling (GEM)
including a previous MAST funded EC project EHUX. The research strategy
of focusing different types of study on the single species Emiliania
proved a very successful way of developing useful collaboration between
a disparate group of specialists. The CODENET project develops this
by taking a set of six carefully selected taxa. These will allow sets of
case studies to be built up and provide a controlled sampling of the
The CODENET project incorporates 15 different research tasks, or
as indicated in the figure below. These basically fall into two main
Culture based biological and biochemical studies
Coccolithophorids can be maintained in culture thus allowing a range of
laboratory based studies. Isolating and maintaining cultures
significant effort, so a key aspect of the CODENET strategy is to
considerable resources to obtaining cultures and then to make them
directly to the participant teams. This maximises the value of the
isolation and avoids duplication of effort. Culture based research
include life-cycle studies, molecular genetics, study of lipid
and pigment composition, study of coccolith carbonate stable isotope
and trace element composition, ultrastructural studies of cytology and
biomineralisation, physiological studies on the effect of variation in
culture conditions on growth rates and coccolith morphology.
Oceanographic and Geological Sample based studies
Coccolithophorids are abundant in a wide range of types of samples,
phytoplankton samples collected during oceanographic cruises, sediment
trap time series samples of material sinking through the water column,
surface sediment samples of recent assemblages and geological samples
a continuous record of evolutionary change. Each of these types of
provides different types of information and is usually studied
Within the CODENET project we are including study of each sample type,
allowing integration of results to address particular questions (see
below). In most cases common samples sets are being used by different
teams each studying particular taxa.
The scale of the CODENET project enables us to approach
fundamental aspects of coccolithophorid biology and to address questions
which cannot be effectively answered by single research studies. As
below and indicated in the diagram above the project is designed
to address a range of objectives within three work areas:
1. Evolutionary Biodiversity
Taken together studies on the six taxa enable us to investigate diversity
across the coccolithophorids and to determine its relationship to
Our key objectives are to:
- Determine the major patterns of biodiversity in coccolithophorid
biomarker composition, photosynthetic pigments, cytology and plastid
- Re-evaluate the phylogeny of the coccolithophorids using separate and
combined analyses of: molecular genetic (AWI), morphological (NHM) and
biochemical (NIOZ, CSIC) data and compare this with the palaeontological
record of coccolithophorid evolution (NHM, ETHZ). Calculate divergence
times of groups and rates of evolution, including molecular clock
- Reconstruct the sequence of major evolutionary steps in
lipid biochemistry, plastid evolution, and life cycle
2. Microevolution and Species Level Variation
Each of the six taxa will provide detailed case studies of evolution and
species-level variation including complimentary studies of living and
material. Our key objectives are to:
- Evaluate which aspects of variation represent genotypic vs.
or ontogenetic variation.
- Determine whether intra-specific variability in morphology,
and biochemistry are correlated, defining discrete sub-species.
- Determine whether physiological adaptation occurs within local
independently of other genotypic characters.
- Determine whether microevolution occurs by (sub-)species selection
or effectively sympatric evolution within ocean-scale populations.
3. Coccolithophorid Ecology
By building up detailed knowledge of the biology of key species and
a range of types of population studies we aim to make a fundamental
of our understanding of coccolithophorid ecology, in particular to:
- Determine whether coccolithophorids as a group occupy a distinctive
ecological niche, and if so characterise it.
- Determine which aspects of intra- or inter-specific assemblage
are most valuable for palaeoecological calibrations and develop
- Determine the extent to which coccolithophorid carbonate accumulation
rate is affected by species composition and evolution.
- Develop and calibrate coccolith-based geochemical palaeoproxies for palaeoceanographic research.