@conference {2013, title = {Gastropod associations as a proxy for seagrass vegetation in a tropical carbonate setting (San Salvador, Bahamas) }, booktitle = {Geological Society of America Abstracts with Programs}, year = {2012}, address = {Charlotte, North Carolina. }, abstract = {

Seagrass ecosystems play an important role in sedimentation processes and nutrient cycling and support local biodiversity by providing food and shelter for numerous associated organisms. These ecosystems have been around since the Late Cretaceous. In order to understand their emergence in geological time and their response to past perturbations we have to be able to recognize seagrass communities in the fossil record. However, seagrass itself hardly fossilizes and therefore we are searching for indirect indicators to recognize ancient seagrass vegetation. In this contribution we review molluscan evidence for palaeo-seagrass settings. Indicator species are rare since the majority of seagrass associated molluscs occurs in other marine habitats as well. Furthermore, those habitats appear to be patchy, both spatial and temporal, resulting in mixed occurrences of seagrass and non-seagrass faunas. Often only the high abundance of certain mollusc groups and the general taxonomic composition of a fauna points to seagrass environments. However, the distribution of gastropod trophic guilds in species richness versus abundance data appears to yield patterns that may be very characteristic for the identification of fossil seagrass associated faunas. We are currently applying Indirect PaleoSeagrass Indicators (IPSI\’s) to a number of fossil and modern shelly samples, both from seagrass and non-seagrass environments. We also briefly review potential sedimentary and geochemical IPSI\’s as well as fossil groups different than molluscs. Identifying seagrass environments enables us to assess diversity trends in such ecosystems through time and to study their response over time intervals with major environmental and climate change.

}, author = {Sonja Reich} } @conference {2013, title = {Diversity, abundance and taphonomic patterns across bivalve dead assemblages associated with sea grass beds, San Salvador, the Bahamas}, booktitle = {Geological Society of America Abstracts with Programs}, year = {2012}, address = {Charlotte, North Carolina. }, abstract = {

Seagrass ecosystems play an important role in sedimentation processes and nutrient cycling and support local biodiversity by providing food and shelter for numerous associated organisms. These ecosystems have been around since the Late Cretaceous. In order to understand their emergence in geological time and their response to past perturbations we have to be able to recognize seagrass communities in the fossil record. However, seagrass itself hardly fossilizes and therefore we are searching for indirect indicators to recognize ancient seagrass vegetation. In this contribution we review molluscan evidence for palaeo-seagrass settings. Indicator species are rare since the majority of seagrass associated molluscs occurs in other marine habitats as well. Furthermore, those habitats appear to be patchy, both spatial and temporal, resulting in mixed occurrences of seagrass and non-seagrass faunas. Often only the high abundance of certain mollusc groups and the general taxonomic composition of a fauna points to seagrass environments. However, the distribution of gastropod trophic guilds in species richness versus abundance data appears to yield patterns that may be very characteristic for the identification of fossil seagrass associated faunas. We are currently applying Indirect PaleoSeagrass Indicators (IPSI\’s) to a number of fossil and modern shelly samples, both from seagrass and non-seagrass environments. We also briefly review potential sedimentary and geochemical IPSI\’s as well as fossil groups different than molluscs. Identifying seagrass environments enables us to assess diversity trends in such ecosystems through time and to study their response over time intervals with major environmental and climate change.

}, author = {B. Cecares and Sonja Reich} } @conference {2015, title = {Diversity and palaeoecology of Miocene coral-associated molluscs from East Kalimantan}, booktitle = {SAGE2013: Southeast Asian Gateway Evolution}, year = {2013}, address = {Museum fuer Naturkunde, Berlin}, abstract = {

Currently, SE Asia is the global marine centre of diversity. High diversity is concentrated in and around reefs. A large variety of organisms, including corals and fish, but also molluscs, crustaceans and echinoderms contribute to this high diversity. In order to understand the timing and the context of the origin of the modern biodiversity hotspot, the fossil record needs to be documented. However, reef facies often suffer strong diagenesis, compromising the fossil record of reef and reef-associated organisms. Here we present an assessment of a well-preserved Late Miocene mollusc fauna from Bontang (East Kalimantan, Indonesia). The fauna is found in association with branching corals, dominated by Dictyaraea. The mollusc fauna is dominated by predatory and browsing carnivorous snails and includes reefal indicators such as the gastropod Coralliophyla and the bivalve Tridacna. The new Bontang fauna gives a glimpse of the diversity and ecological composition of a Late Miocene mollusc fauna from a so-called coral-carpet environment.

}, author = {Aires Kusworo and Sonja Reich and Frank P. Wesselingh and Nadiezhda Santodomingo and Willem Renema} } @conference {2014, title = {Mollusks as seagrass indicators in the Miocene of Indonesia}, booktitle = {SAGE 2013: Southeast Asian Gateway Evolution}, year = {2013}, address = {Museum fuer Naturkunde, Berlin}, abstract = {

Today\’s centre of maximum marine biodiversity is located in the Indo-Malayan region. Understanding the development of this biodiversity hotspot through the Cenozoic could answer numerous questions about the responses of highly diverse faunal associations to small and large scale environmental changes. When assessing marine biodiversity through time comparisons of taxon diversity are only meaningful when comparing faunas from similar habitats. To evaluate diversity through time within the same ecological setting, it is indispensable to reliably discriminate different habitats. A good example for the difficulties which may occur when identifying marine paleo-habitats is the challenge of recognizing seagrass vegetation in the fossil record. Due to the low preservation potential of marine angiosperms, indirect indicators, e.g. associated organisms with a higher potential for preservation, are commonly used to infer the presence of seagrass meadows in the geological past. Because of their high fossilization potential and their abundance in marine habitats mollusks yield the possibility to be useful paleo seagrass indicators. Here we assess the potential use of indicator species, species and feeding guild composition of whole assemblages, as well as stable isotope signals in shells for their suitability to determine seagrass vegetation in the Miocene of Indonesia.

}, author = {Sonja Reich and Frank P. Wesselingh and Willem Renema and Warter, Viola} }