Category Archives: Science

Climate Models and Eocene Isotopes, or How to Make My Head Hurt – #365papers – 2017 – 49

#365papers for February 18, 2017

Feng, Poulsen, Werner, Chamberlain, Mix, and Mulch, 2013, Early Cenozoic evolution of topography, climate, and stable isotopes in precipitation in the North American cordillera: American Journal of Science, v. 313, p. 613-648.

What’s it about?

Isotopes of oxygen and hydrogen in precipitation vary based on multiple factors, including how far from water vapor sources (usually the ocean) the precipitation is taking place, and whether or not there are mountains present, which can deflect and change patterns and amounts of precipitation. Because of this, we can use isotopes of oxygen from rocks and fossils, which reflect ancient precipitation, and understand the pattern and timing of uplifts of mountains.

This paper goes a step further, by using mathematical models to predict what oxygen isotopes of precipitation should have looked like based on a few ideas of how the Rocky Mountains may have come up.Continue reading “Climate Models and Eocene Isotopes, or How to Make My Head Hurt – #365papers – 2017 – 49”

Two Papers, Two Authors, One Year, Same Result, But… – #365papers – 2017 – 48

#365papers for February 17, 2017

Bender, M.M., 1971, Variations in the 13C/12C ratios of plants in relation to the pathway of photosynthetic carbon dioxide fixation: Phytochemistry, v. 10, p. 1239-1244.

Smith, B.N. and Epstein, S., 1971, Two categories of 13C/12C ratios for higher plants: Plant Physiology: v. 47, p. 380-384.

Two papers, one topic.

What are these about?

Both of these papers are important first steps in our understanding of how stable isotopes can be used to understand plant physiology.Continue reading “Two Papers, Two Authors, One Year, Same Result, But… – #365papers – 2017 – 48”

Analyzing Salty Waters with Laser Spectroscopy – #365papers – 2017 – 47

#365papers for February 16, 2017

Skrzypek and Ford, 2014, Stable Isotope Analysis of Saline Water Samples on a Cavity Ring-down Spectroscopy Instrument: Environmental Science & Technology, v. 48, p. 2827-2834.

What’s it about?

This is a methods paper about how to analyze saline (salty) waters with the new laser-based isotope analyzers. It discusses several solutions to the problems that can arise when dealing with salty waters.Continue reading “Analyzing Salty Waters with Laser Spectroscopy – #365papers – 2017 – 47”

Paleogene Mountains, Rivers, Lakes,… and Isotopes – #365papers – 2017 – 46

#365papers for February 15, 2017

Davis, Mulch, Carroll, Horton, and chamberlain, 2009, Paleogene landscape evolution of the central North American Cordillera: Developing topography and hydrology in the Laramide foreland: Geological Society of America Bulletin, v. 121, p. 100-116.

What’s it about?

This paper uses isotopes of oxygen, carbon, and strontium from multiple areas along the east edge and middle of the Rocky Mountains to explore the timing of the uplift of the Rockies, and to understand how the new mountains affected climate locally.Continue reading “Paleogene Mountains, Rivers, Lakes,… and Isotopes – #365papers – 2017 – 46”

Doctoral Day! – Mammals of the Torrejonian-Tiffanian (Paleocene) Transition – #365papers – 2017 – 45

#365papers for February 14, 2017

Higgins, 2003, A Wyoming succession of Paleocene mammal-bearing localities bracketing the boundary between the Torrejonian and Tiffanian North American Land Mammal “Ages”: Rocky Mountain Geology, v. 38.

What’s it about?

This paper discusses the nature of the boundary between two adjacent North American Land Mammal “Ages” (NALMAs). NALMAs are defined by the presence or absence of certain mammal species and are usually quite different in species composition. The 136 localities studied here bracket the Torrejonian-Tiffanian boundary, so we can examine the transition more closely.Continue reading “Doctoral Day! – Mammals of the Torrejonian-Tiffanian (Paleocene) Transition – #365papers – 2017 – 45”

The Last Glacial Maximum in Wyoming. A Story From Tooth Enamel – #365papers – 2017 – 44

#365papers for February 13, 2017

Kohn and McKay, 2012, Paleoecology of the late Pleistocene-Holocene faunas of eastern and central Wyoming, USA, with implications for LGM climate models: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 326-328, p. 42-53.

What’s it about?

This paper uses measurements of stable isotopes of carbon and oxygen from tooth enamel to interpret past mean annual precipitation and other climatic variables for two caves in Wyoming. Continue reading “The Last Glacial Maximum in Wyoming. A Story From Tooth Enamel – #365papers – 2017 – 44”

Taxonomy, Nomenclature, Species, and the Endangered Species Act – #365papers – 2017 – 43

#365papers for February 12, 2017 – DARWIN DAY

Leslie, 2014, Impacts of phylogenetic nomenclature on the efficacy of the U.S. Endangered Species Act: Conservation Biology, v. 29, p. 69-77.

What’s it about?

The U.S. Endangered Species Act depends upon the definition of ‘species’ for it to work. However, ‘species’ is not a concept for which all biologists agree upon a definition, and there is plenty of debate about how traditional Linnaean taxonomy can fail. This paper focuses on the impact of using a different classification scheme called PhyloCode, and its definition of species.Continue reading “Taxonomy, Nomenclature, Species, and the Endangered Species Act – #365papers – 2017 – 43”

Brewing with Hybrid Yeast – #365papers – 2017 – 42

#365papers for February 11, 2017

Krogerus, Magalhaes, Vidgren, and Gibson, 2017, Novel brewing yeast hybrids: creation and application: Applied Microbiology and Biotechnology, v. 101, p. 65-78.

What’s it about?

This paper discusses the state of knowledge about yeasts used in brewing. It focuses especially on yeasts used for brewing lagers (bottom-fermentation at low temperature).Continue reading “Brewing with Hybrid Yeast – #365papers – 2017 – 42”

How Do the Early Processes of Fossilization Affect the Chemistry of Bones and Teeth? – #365papers – 2017 – 41

#365papers for February 10, 2017

Tutken, Vennemann, and Pfretzschner, 2008, Early diagenesis of bone and tooth apatite in fluvial and marine settings: Constraints from combined oxygen isotope, nitrogen and REE analysis: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 266, p. 254-268.

What’s it about?

This paper discusses how we can determine how altered a geochemical signal in a fossil bone or tooth might be, comparing bones and teeth that fossilized in both freshwater (river) and marine (ocean) environments. The authors used collagen content, nitrogen content, and the abundance of Rare Earth Elements (REEs) to attempt to estimate alteration.Continue reading “How Do the Early Processes of Fossilization Affect the Chemistry of Bones and Teeth? – #365papers – 2017 – 41”

How Can Paleobiology Help Conservation Efforts? – #365papers – 2017 – 40

#365papers for February 9, 2017

Barnosky et al, 2017, Merging paleobiology with conservation biology to guide the future of terrestrial ecosystems: Science, v. 355, eaah4787.

What’s it about?

This paper discusses the kinds of decisions that must be made by conservation biologists when trying to save species and ecosystems. These decisions depend on the overall goals of conservation: the maintain and restore current ecosystems, to save species, or to maximize biodiversity for example. These decisions can be informed by paleobiology.Continue reading “How Can Paleobiology Help Conservation Efforts? – #365papers – 2017 – 40”