The application of molecular clock concepts in phylogenetics permits estimating the divergence times of clades with an incomplete fossil record. However, the reliability of this approach is disputed, because the resulting estimates are often inconsistent with different sets of fossils and other parameters (clock models and prior settings) in the analyses. Here, we present the λ statistic, a lik...

Glycerol dibiphytanyl glycerol tetraether (GDGT) lipids are part of the cellular membranes of Thaumarchaeota, an archaeal phylum composed of aerobic ammonia oxidizers, and are used in the paleotemperature proxy TEX86 . GDGTs in live cells possess polar head groups and are called intact polar lipids (IPL-GDGTs). Their transformation to core lipids (CL) by cleavage of the head group was assumed t...

This study attempts to analyze interlanguage production made by ten eight-grade students who were enrolled in one of the secondary schools Jakarta. Interlanguage happens when a learner talk target language but their linguistic framework is still source (any prior they knew beforehand). It intended explore kinds that occur recount writing and explain potentials why errors emerge writing. The dat...

Abstract Reports on the presences of petrified wood fossils in Padangcermin, Lampung, are rare, no strong examination that expose scientific concern its paleoenvironment perspective. By published geological map, these was found area labelled as Cretaceous sedimentary rock (145-66 mya). Recently, known oldest fossil Indonesia, is from Miocene epoch (23.03-5.33 It an interesting circumstance to e...

Introduction: Mars Global Surveyor Thermal Emission Spectrometer data indicate regions with significant levels of hematite (_Fe2O3). Fe-oxides, like hematite, can form as aqueous mineral precipitates and as such may preserve microscopic fossils or other biosignatures. Several potential terrestrial analogues to martian hematite like hydrothermal vents have preserved microfossils [1]. Microbial f...

Many fossils are assumed to take up trace elements by a process of combined diffusion plus adsorption (DA), yet in principle composition profiles can be explained by several different diffusion-limited processes, including diffusion plus reaction or recrystallization (DR) and double-medium diffusion (DMD). The DA and DMD models are supported by REE and U composition profiles across fossil teeth...