Abstract Exceptionally preserved fossil eggs and embryos provide critical information regarding paleoembryogenesis, reproductive strategies, the early ontogeny of arthropods, but rarity preservation both egg-bearing organisms in situ limits their use detailed evolutionary developmental (evo-devo) studies. Burgess Shale-type deposits preserve rare instances arthropods as carbonaceous compression...

ABSTRACT Although the fibrous plant material called Affenhaar from middle Eocene lignites of Geiseltal in Germany has been repeatedly studied for over 172 years, modern imaging and chemical analyses have enabled a deeper understanding its composition preservation within parent plant. Known English as “monkeyhair,” represents very rare case fossil laticifers, latex-bearing ducts plants. Here we ...

The Miocene aged Shanwang Formation from the National Geopark in China represents a succession of lacustrine diatomaceous shales containing an abundant and diverse biota with lagerstätte fossilization soft tissues. To date, has not been investigated for cyclostratigraphy nor it dated high precision methods. Now we use thorium data as paleoenvironmental paleoclimatic proxy to conduct detailed cy...

We report here on magnetite- and wustite-encrusted and geometrically oriented microbial-like structures (MLS) attached to the surfaces of hematite (alpha-Fe(2)O(3)) crystals in a banded iron formation. Field emission scanning electron microscope (FE-SEM) and scanning electron microscope (SEM) imaging showed a 3-D network of MLS arranged in 1 microm x approximately 20 microm coccoidal-like chain...

Progressive biomineralization of a skeleton occurs during ontogeny in most animals. In fishes, larvae are poorly mineralized, whereas juveniles and adults display a progressively more biomineralized skeleton. Fossil remains primarily consist of adult specimens because the fossilization of poorly-mineralized larvae and juveniles necessitates exceptional conditions. The Miguasha Fossil-Lagerstätt...

Our perception of biodiversity in the geological past is incomplete and biased because most organisms did not have mineralized skeletons and therefore had little chance of fossilization. This especially refers to shallow-water marine environments, rarely represented by localities with exceptional preservation of fossil material (known as taphonomic windows or Konservat-Lagerstätten). Such extra...

Fossils are essential to the reconstruction of the evolution of life and episodes in Earth history. Fossil skeletal material serves as the repository of chemical data widely used in the reconstruction of the Earth’s climate–ocean system at various time scales. Knowledge of biomineralization – the processes associated with the formation of mineralized biological structures – is essential to prop...

The oxygen isotope ratio of CO(2) liberated from structural carbonate in tooth enamel apatite was measured at phosphoric acid reaction temperatures of 25 degrees C, 60 degrees C and 90 degrees C, and it was found that apparent acid fractionation factors for pristine enamel, fossilized enamel, and calcite follow different temperature relationships. Using sealed vessel reactions normalized to alp...

The human language faculty is a bidirectional system, i.e. it can be used by processes of approximately equal computational complexity to understand and to generate utterances of a language. We assume the general framework of optimality theory and treat the language faculty as a constraint-based system where the very same constraints are uses both in comprehension and in generation. In the simp...