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INA Workshop on extant
Coccolithophorid research
Institute of Marine
Biology of Crete, Heraklion, Greece, October 1-6, 2003
Extant coccolithophores have attracted
a wide range of research over the past decade including
much research on topics such as dimethyl sulphide and
alkenone production, physiological ecology, carbon uptake
mechanisms, remote sensing and modelling of blooms,
but also taxonomy-based research on biodiversity, molecular
genetics, ecology, biogeography and flux estimation.
As a result of the latter strand of research there is
now a significant number of specialists world-wide who
are identifying and studying extant coccolithophores.
This workshop was proposed to allow
these specialists to share research results, gain some
training, and discuss methods and research priorities.
The workshop was proposed at the INA9 conference in
Parma in 2002 and Dr. Maria Triantaphyllou of Athens
University who has recently commenced a very productive
study of coccolithophores in the Aegean Sea offered
to host it. Through collaboration with the Institute
of Marine Biology of Crete, Maria was able to organise
the meeting at minimal cost in a superb venue. The IMBC
is located on the Aegean coast of Crete and we stayed
in a very civilised tourist hotel 15 minutes walk down
the beach at a specially negotiated discount rate. Late
summer is probably an ideal time to visit Greece with
the climate still consistently sunny but not oppressively
hot, the sea pleasantly warm and the main tourist hordes
back home. Needless to say we thoroughly enjoyed the
swimming, bars, food, archaeological excursions and
remarkably friendly environment.
We also did, however, manage to have
a very useful meeting scientifically. In total about
40 people attended the workshop including a large home
team from Athens and Crete. There were also substantial
contingents from Germany, Italy, the USA and Portugal
and a scattering from other countries across Europe
and beyond. The British contingent was a bit tricky
to enumerate but arguably included in addition to myself,
three exiles Ian Probert (Caen), Ric Jordan (Yamagata)
and Pat Quinn (Zurich) and two recent imports Jens Herrle
(now at Southampton) and Sebastian Meier (now at the
NHM working on calcareous dinoflagellate with Susanne
Feist-Burkhardt), plus Markus Geisen who is now at Bremerhaven
after his extended stay with me at the NHM. Just as
importantly as the international diversity there was
a wide age range with a healthy predominance of PhD
students and young post-docs, and a 50:50 balance of
men and women.
We had one training day plus two and
a half days of scientific sessions including 17 talks,
15 poster presentations (with 10 minute introductory
talks) and 4 workshop sessions. This was a relatively
relaxed schedule which allowed everyone to present their
work and with a small specialist audience there was
an excellent level of discussion, and if the time keeping
was rather lax at times it did not seem to matter as
we just continued a bit later.
The training day was arranged by Ian
Probert and Colomban de Vargas (Rutgers University,
New Jersey), with assistance from Markus Geisen and
Pat Quinn. Ian and Colomban gave extended overviews
on the biology of haptophytes and on application of
molecular genetics to planktonic protists. Then Ian,
Pat and Markus organised a practical on isolation of
cultures of coccolithophores; including demonstration
of plankton sampling from the beach and a chance to
test our manipulation skills by isolating cells with
a micropipette (which makes picking small forams seem
very easy). Since most nannoplankton workers still come
from a geological background this session was very welcome.
The presentations were organised into
sessions on Coccolithophorid Ecology, Biology, Biogeography,
Coccolithophores and marine carbonate cycles, and Evolutionary
Biodiversity – Taxonomy. In terms of taxonomy we
are at a relatively advanced stage, as symbolised by
the publication, in time for the meeting, of a new CODENET
sponsored Guide to Extant Coccolithophore Taxonomy (Young
et al. 2003). However, recent research has highlighted
the fact that many conventional species are actually
clusters of cryptic or pseudo-cryptic sibling species.
New work in this area included documentation of fine
scale variation in Florisphaera profunda by Pat Quinn
in Coccolithus pelagicus by Aurea Pariente, and in the
Papposphaeraceae by Lluisa Cros. In parallel the recent
work documenting holococcolith-heterococcolith life-cycle
associations continued, with new results from Maria
Triantaphylou and extended workshop discussion on the
nomenclatural implications. These themes in turn strongly
influenced presentations and discussion on ecology of
coccolithophores. A key presentation by Patrizia Ziveri
on distribution of selected species in the Atlantic
based on a large database of Holocene sediment samples
both revealed patterns which had previously been barely
recognised and showed that this type of biogeographic
data urgently needs to be re-collected using modern
taxonomy.
There was fine set of sediment trap
studies, including a three year series described by
Meral Kobrich from off NW Africa with intriguingly strong
inter-annual variation. New lines of ecological research
were suggested by research of Maria Triantaphylou on
the potential of coccolithophores as pollution indicators
using both assemblage reduction and malformation as
proxies, with disticty encouraging preliminary results,
and of Markus Geisen on testing of functional hypotheses
through measurement and modelling of the mechanical
properties of coccospheres.
Information preservation in the fossil
record was a less expected theme but reflects the fact
that a key objective of much work on extant coccolithophores
has been to provide data for palaeoecological analyses.
Harald Andruleit and Jeremy Young highlighted the problem
of information loss with only a fraction of the extant
biodiversity and assemblage variability being transmitted
into the fossil record or even the sediment trap record.
Conversely Karl-Heinz Baumann showed that on a large
scale there was remarkably high fidelity between the
biogeography of coccolithophores in Nordic Seas as observed
in the plankton and in the surface sediments. In parallel
Marie-Pierre Aubry argued that large scale patterns
in the Cenozoic fossil record indicated strong differences
from modern ecology and could not be explained away
by taphonomic processes. She argued that a major challenge
for palaeontologists was to interpret this record, informed
by knowledge of modern coccolithophore ecology but aware
that the present may be only a partial key to the past.
Perhaps the overall conclusion of the
meeting was that we now have firm foundations for future
research, especially on coccolithophore ecology, as
a result of finally having a reasonable understanding
of the biology and taxonomy of coccolithophores. Typical
questions identified during the workshop sessions include
(1) Will the pattern of global pandemicity indicated
by current taxonomy prevail at the finer taxonomic level
of pseudo-cryptic species? (2) Is the pattern of holococcolithophore
life-cycle stages occupying more oligotrophic niches
than the heterococolith life-cycle stages valid as a
general model? It is an interesting phase of research
and clearly coccolithophores do have the potential to
become the best understood group of oceanic phytoplankton.
Jeremy
Young
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