Scientific sessions

 

NEWS: key-notes added

 

The six scientific sessions will include keynote talks, volunteered talks and poster presentations on all aspects of the study of brachiopods, from systematics and evolution to biostratigraphy, palaeoecology, palaeobiogeography, geochemistry, biomineralization and the biology of extant brachiopods.

If possible, parallel sessions will be avoided to enhance multi- and interdisciplinary exchange of ideas between researchers involved in different aspects of brachiopod research.

 

Plenary Session

1. Uwe Brand (Brock University, Canada), Modern brachiopods: superheroes of archives.

2. Elizabeth Harper (University of Cambridge, UK), Living brachiopods: hanging on or fit for a

modern world?

3. Lars Holmer (Uppsala University, Sweden), Brachiopod phylogeny in the Cambrian.

 

S1. Systematics and evolution

Convenors: S. Carlson (University of California, Davis, U.S.A.), F. Alvarez (Universidad de Oviedo, Spain), J. Jin (Western University, Canada).

Description: Determining brachiopod evolutionary pattern and process is a goal that we all share.

Systematic biology and evolutionary palaeobiology – and the construction of taxonomies and phylogenies – provide the foundation for our investigations. Which data do we use – morphology, ontogeny, molecular sequences, genomics, stratigraphy, biogeography, others? Which methods are most appropriate for analyzing those data? How do we interpret the results? The current classification allows us to communicate with one another about groups of brachiopods recognizable by patterns of size and shape, over time and space. Understanding the history and structure of this classification enables us to test hypotheses about character homology and patterns of character change over geological time, and determine how closely the classification

reflects patterns of phylogenetic relationship based on the evolutionary process of common ancestry. In this session, we will explore some of the many answers to questions regarding evolutionary pattern and process, at all scales of time and space, from populations to phyla.

 

Key-notes

Aodhan Butler (Stanford University, U.S.A), Phylogenomic analysis of Brachiopoda:  revealing the revolutionary history of biomineralisation with an integrated palaeontological and molecular approach.

Alycia Stigall (Ohio University, U.S.A), Brachiopods as key to evolutionary theory: from foundational systematics to phylogenetics to speciation and biogeography.

 

S2. Taphonomy and Palaeoecology

Convenors: A. Pérez-Huerta (University of Alabama, U.S.A.), A. Tomašových (Slovak Academy of Sciences, Bratislava, Slovakia).

Description: Brachiopods are one of the most successful groups of marine invertebrates throughout the Phanerozoic. Despite their abundance and diversity in the fossil record, there are numerous gaps in our understanding of their palaeoecology and palaeobiogeography. Although ecological and functional analyses of extant brachiopods provide useful insights into functional morphology of extinct brachiopods, this perspective can be limited by ecological breadth of present-day brachiopod species pool. There is still limited information about the mode of life of extinct brachiopods, interactions with other benthic organisms, their distribution along environmental gradients, and their response to past environmental changes, which can be important in palaeontological and sedimentological studies involving brachiopod faunas. The recent discovery of exceptional preservation of faunas across the Phanerozoic, in addition to the use of new analytical techniques and computer simulations, provides a new insight into the subject.

In this session, we welcome scientific contributions that help expand our understanding of brachiopod taphonomy, palaeoecology, and palaeobiogeography, including analyses of spatial and temporal variability in abundance, size, and diversity of brachiopod communities, while completing our overall knowledge of the phylum.

 

Key-note

Yuta Shiino (Niigata University, Japan), Form and function of fossil brachiopods: Insights into evolutionary morphology.

 

S3. Ecosystems in time and space

Convenors: D.A.T. Harper (Durham University, United Kingdom).

Description: Brachiopods have been major and important players in ancient marine ecosystems since the bas of the Cambrian. Brachiopods have dominated all manner of proximal to distal shelf marine facies, explored the deep sea and spread across all the World’s latitudes, to varying degrees, throughout the entire Phanerozoic. The early history of the group, within the Cambrian Evolutionary Fauna, is spectacular, with many new morphologies adapted already to a wide range of environments and ecological niches. The Great Ordovician Biodiversification established the phylum as a dominant part of the Palaeozoic Evolutionary Fauna and although severely attenuated during the end Permian extinction events, all three subphyla remained regionally important within the Modern Evolutionary Fauna. This symposium explores the participation of the phylum in ecosystems through time and across changing environments and provinces during the Phanerozoic, focusing on brachiopod palaeoecology and palaeobiogeography.

 

Key-notes

Zhifei Zhang (Northwest University, China), Palaeoecological complexities during the Cambrian Explosion: Evidence from brachiopods.

David A.T. Harper (Durham University, United Kingdom), The rise of the rhynchonelliform brachiopods: The role of the Great Ordovician Biodiversification Event.

Richard Twitchett (Natural History Museum, United Kingdom), Brachiopods in post-Permian hothouse worlds.

 

S4. Mass extinctions and recovery

Convenors: S. Shen (Nanjing Institute of Geology and Palaeontology, China), A. Baliński (Polish Academy of Science, Warsaw, Poland), F. Garcia Joral (Complutense University of Madrid, Spain).

Description: Mass extinctions are biological events causing widespread and dramatic decrease in biodiversity on Earth. Such events are identified by sharp changes in diversity and abundance of organisms. At least five big mass extinctions have been well recognized during the Phanerozoic. Brachiopods are one of the most diverse benthic groups during the Phanerozoic. They suffered severe loss during the “Big Five”. In addition to the five mass extinctions, there are numerous moderate and minor events as well which significantly affected brachiopods and other associated organisms. How did those events happen? What are their extinction patterns? Why did some become extinct and some others not? Proposed extinction hypotheses include bolide impact, massive volcanisms, overturn of stratified oceans and poisoning of shelf waters, and short- and long-term climate changes (both warming and cooling) and drop in sea level. In addition, how did brachiopods survive the extinction and adapt in response to the environmental change? What were the patterns of recovery following devastating extinction events? All topics related to these questions are warmly welcome in this session.

 

Key-note

Attila Vörös (Hungarian Natural History Museum, Hungary), Mass extinctions and fatal extinctions in the history of brachiopods: post-Paleozoic cases.

 

S.5 Biologic mineralization of natural functional materials and archives of geochemical proxies

Convenors: E. Griesshaber (Ludwig-Maximilians- Universität München, Germany), A. Eisenhauer (GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany).

Description: Biological hard tissue formation does not occur from supersaturated aqueous solutions, but from crystallization under well-defined cellular control. Biologic mineralization is an assembly process of self-organization at various scales, from the molecular to the macro-scale. Mineral formation starts with the segregation of amorphous precursors. A subsequent ordered and oriented growth process produces mesocrystals, and arrays of mesocrystals form the final skeleton/shell. Cell produced macro-molecules transform amorphous aggregates into crystalline phases, and they regulate the onset, growth and cessation of crystallization. They are also responsible for the ability of biological systems to respond and adapt to environmental change.

The Phanerozoic Eon marks the beginning of biomineralized tissue formation, archives that provide information on environment, evolution, land-ocean interaction and climate change. Knowledge of these events is gained from trace element and isotopic compositions obtained from skeletons of past and present organisms. However, environmental and climate changes can only be understood when fine details are fully assessed, a task dependent on a profound understanding of the sampled material. Species dependent vital effects, time and pressure dependent physical and chemical alterations overprint original signals, and time series of trace element and isotope records become difficult to interpret. Thus, the understanding of pathways and processes of biological hard tissue formation and of stages of hard tissue alteration is of fundamental

importance.

This session invites contributions addressing studies of both biomineralization of fossil and modern brachiopods and new developments and findings on geochemical proxies of the brachiopod archive for the reconstruction of past and present oceans and climate dynamics.

 

Key-notes

Andreas Ziegler (University of Ulm, Germany), Mechanisms of calcite fibre formation in Magellania venosa.

Claire Rollion-Bard (Institut de Physique du Globe de Paris, France), What can geochemical proxies tell about the biomineralization processes in brachiopods?

 

S.6 Modern brachiopods

Convenors: A. Bitner (Polish Academy of Science, Warsaw, Poland), M. Cusack (University of Stirling, United Kingdom), C. Lüter (Museum für Naturkunde, Berlin, Germany).

Description: Only some 400 species of Brachiopoda representing five major clades within the phylum are found in oceans. Despite this diminished diversity in comparison to what is known from the fossil record, modern brachiopods provide an indispensable resource of biological data for evolutionary research. First and foremost this applies to all DNA/RNA based methods, but also includes evolutionary developmental biology studies, eco-physiological studies, and detailed morphological examination of soft tissues with histological and/or electron microscopic techniques. Additionally, living brachiopods can be used to calibrate deep time reconstructions of abiotic environmental parameters (see e.g., Session S5). Looking at modern brachiopods from different methodological angles, this session aims to highlight the importance of biological

phenomena and processes to understand the evolution of the whole phylum.

 

Key-note

Elena Temereva (Moscow University, Russia), Organization of the lophophore in linguliform Pelagodiscus atlanticus and the evolution of the lophophore in brachiopods.

 

 

 

 

 

8th International Brachiopod Congress: "Brachiopod in a changing planet: from the past to the future". 8brachcongress@unimi.it