A5045809850- Paleontology and Stratigraphy of Fossils
- Marine Biology and Ecology Research
- Geological and Geophysical Studies
- Geology and Paleoclimatology Research
- Geochemistry and Elemental Analysis
- Geological formations and processes
- Coral and Marine Ecosystems Studies
- Paleontology and Evolutionary Biology
- Geological and Geochemical Analysis
- Marine and coastal plant biology
- Evolution and Paleontology Studies
- Hydrocarbon exploration and reservoir analysis
- Geological Studies and Exploration
- Protist diversity and phylogeny
- Geochemistry and Geologic Mapping
- Echinoderm biology and ecology
- Ichthyology and Marine Biology
- Cephalopods and Marine Biology
- Ocean Acidification Effects and Responses
- Isotope Analysis in Ecology
- Forensic Anthropology and Bioarchaeology Studies
- Environmental and Cultural Studies in Latin America and Beyond
- Maritime and Coastal Archaeology
- Regional Socio-Economic Development Trends
- Botany and Geology in Latin America and Caribbean
University of Wisconsin–Milwaukee
2011-2024
Milwaukee Public Museum
2013-2016
Museum für Naturkunde
2015
Stanford University
2015
GNS Science
2015
University of Minnesota System
2015
University College London
2015
Friedrich-Alexander-Universität Erlangen-Nürnberg
2015
University of California, Berkeley
2015
Nanjing Institute of Geology and Paleontology
2004-2006
Abstract A geologically rapid Neoproterozoic oxygenation event is commonly linked to the appearance of marine animal groups in fossil record. However, there still debate about what evidence from sedimentary geochemical record—if any—provides strong support for a persistent shift surface oxygen immediately preceding rise animals. We present statistical learning analyses large dataset data and associated geological context Palaeozoic record then use Earth system modelling link trends...
Ten phosphatized specimens of a small (<180 micrometers) animal displaying clear bilaterian features have been recovered from the Doushantuo Formation, China, dating 40 to 55 million years before Cambrian. Seen in sections, this (Vernanimalcula guizhouena gen. et sp. nov.) had paired coeloms extending length gut; external pits that could be sense organs; bilateral, anterior-posterior organization; ventrally directed anterior mouth with thick walled pharynx; and triploblastic structure. The...
In developing embryos of some extant spiralian animals, polar lobe formation is one the symmetry-breaking mechanisms for segregation maternal cytoplasmic substances to certain blastomeres and not others. Polar leads unique early cleavage morphologies that include trilobed, J-shaped, five-lobed structures. Fossil similar modern lobeforming are recognized from Precambrian Doushantuo Formation phosphates, Weng'an, Guizhou Province, China. These abundant form a developmental sequence comparable...
Organisms emit, detect, and respond to a huge array of environmental signals. The distribution given signal is dependent, first all, upon the original spatial sources, source landscape. sources can be fixed or moving their output stable ephemeral. Different also occupy same general location, such as insects living on host plant. emitted signals are modified by relevant transport processes, which often strongly scale environment dependent. Chemical signals, for example, propagated diffusion...
The composition of continental crust records the balance between construction by tectonics and destruction physical chemical erosion.Quantitative constraints on how igneous addition weathering have modified continents' bulk are essential for understanding evolution geodynamics climate.Using novel data analytic techniques we extracted temporal trends in sediments' protolith intensity from largest available compilation sedimentary major element compositions: ∼15,000 samples 4.0 Ga to...
Geobiology explores how Earth's system has changed over the course of geologic history and living organisms on this planet are impacted by or indeed causing these changes. For decades, geologists, paleontologists, geochemists have generated data to investigate topics. Foundational efforts in sedimentary geochemistry utilized spreadsheets for storage analysis, suitable several thousand samples, but not practical scalable larger, more complex datasets. As results accumulated, researchers...
Abstract Phosphatized animals and animal embryos of the Neoproterozoic Doushantuo Formation Southwest China provide what is likely earliest fossil evidence for animals, including bilaterians. This research utilizes field petrographic analyses animal-fossil-bearing interval general observations animal-embryo preservation in order to gain insight into taphonomic processes involved these fossils. Results indicate that there are two genetically related phosphatic lithofacies within animal-...
Abstract Ecological studies have revealed that the functional roles of dominant species in modern communities are often more important than overall diversity governing community composition and functioning. Despite this recognition abundance data both required for a complete understanding ecological processes, many paleoecological focus on presence-absence data, possibly because concerns regarding taphonomic fidelity time-averaged fossil accumulations. However, organisms shell beds has been...
Research Article| September 01, 2000 Evolutionary paleoecology of the earliest echinoderms: Helicoplacoids and Cambrian substrate revolution Stephen Q. Dornbos; Dornbos 1Department Earth Sciences, University Southern California, Los Angeles, California 90089-0740, USA Search for other works by this author on: GSW Google Scholar David J. Bottjer Geology (2000) 28 (9): 839–842. https://doi.org/10.1130/0091-7613(2000)28<839:EPOTEE>2.0.CO;2 Article history received: 07 Feb rev-recd: 05 Jun...
Preservation of soft-bodied organisms is exceedingly rare in the fossil record. One way that such fossils are preserved as carbonaceous compressions fined-grained marine sedimentary rocks. These deposits exceptional preservation known Burgess Shale-type (BST) deposits. During Cambrian Period, BST more common and provide a crucial view early animal evolution. The earliest definitive evidence for macroscopic animal-grade found preceding Ediacaran Period. from rarer lack conclusive animals....
Phosphatized fossils from the Neoproterozoic Doushantuo Formation have provided valuable insight into early evolution of metazoans, but preservation these spectacular is not yet fully understood. This research begins to address this issue by performing a detailed specimen-based taphonomic analysis phosphatized metazoan embryos. A total 206 embryos in 65 thin sections Weng'an Phosphorite Member were examined and their levels pre-phosphatization decay estimated. The data produced examination...
Abstract The Copper Harbor Conglomerate is a Mesoproterozoic (1.09 Ga) freshwater sedimentary sequence that outcrops in the Upper Peninsula of Michigan. formation was deposited during infilling failed Midcontinent Rift and contains fluvial, lacustrine, alluvial fan facies. This study describes analyzes small domal structures preserved fluvial sandstone facies within lower portion formation. These range from millimeters to several centimeters diameter height, are convex epirelief on...
Abstract Oxygen bubbles produced during photosynthesis internally deform filamentous cyanobacterial mats, producing distinctive fenestral patterns. Similar textures preserved in ancient microbialites are useful biosignatures when filaments no longer preserved, but have typically been observed within stromatolites. This study describes bubble-associated fenestrae oncoids from the early Cambrian Bayan Gol Formation of Mongolia. Fenestrae appear mm-scale micritic laminae which contain dense...
The Cambrian radiation of complex animals includes a dramatic increase in the depth and intensity bioturbation seafloor sediment known as ‘agronomic revolution’. This transition was coupled with shift dominant trace fossil style from horizontal surficial traces late Precambrian to vertically penetrative fossils Cambrian. Here we show existence first latest Ediacaran: dense occurrences U-shaped Arenicolites marine carbonates Western Mongolia. Their Ediacaran age is established through stable...