The post How do paleontologists identify dinosaur teeth? Smithsonian Curator Matthew Carrano identifies Cretaceous dinosaur teeth from the Washington D.C. area. appeared first on Smithsonian Insider.

The post Learn about the ash that comes from volcanoes with Dr. Liz Cottrell, a geologist from the National Museum of Natural History appeared first on Smithsonian Insider.

The post Smithsonian anthropologist JoAllyn Archambault speaks about the outstanding research of 19th-century anthropologist James Mooney appeared first on Smithsonian Insider.

William Fitzhugh - Edward Nelson's 1877-1881 Western Alaskan Expedition

The post Smithsonian anthropologist William Fitzhugh speaks about Edward Nelson’s 1877-1881 Western Alaskan Expedition appeared first on Smithsonian Insider.

The post Meet Smithsonian archaeologist Stephen Loring and learn how he came work at the Smithsonian’s Arctic Studies Center appeared first on Smithsonian Insider.

The post Conrad Labandiera, Smithsonian palentologist, studies fossils to learn how insects got along before flowering plants arrived appeared first on Smithsonian Insider.

Speeding Up Science from Facebook Stories on Vimeo. In January 2011, Oregon State University ichthyologist Brian Sidlauskas led a research expedition into the little-known Cuyuni […]

The post Facebook comes to rescue of ichythyologists struggling to describe specimens appeared first on Smithsonian Insider.

The post How do paleontologists reconstruct environments from the ancient past? appeared first on Smithsonian Insider.

The Smithsonian Tropical Research Institute

The post Join the longest conversation in tropical biology appeared first on Smithsonian Insider.

Seven red panda cubs were born at the Smithsonian Conservation Biology Institute! The cubs were born to mothers Nutmeg, Regan and Leo Mei. Keepers are […]

The post Red Panda Cubs Born at Conservation Biology Institute appeared first on Smithsonian Insider.

This video is from a course on Taxonomy and Ecology of Caribbean Sponges, held in the Smithsonian Tropical Research Institute’s Bocas del Toro Research Station […]

The post Caribbean Sponge Ecology appeared first on Smithsonian Insider.

Oct. 4, 2016—The Smithsonian Conservation Biology Institute welcomed an Eld’s deer fawn Oct. 2 around 4:30 p.m. Both the fawn and her mom Sienna appear […]

The post Eld’s Deer Fawn Born at the Smithsonian Conservation Biology Institute appeared first on Smithsonian Insider.

Meet Nick Pyenson, one of our paleontologists at the National Museum of Natural History. His job as a time traveler is to make discoveries about […]

The post Time Travel With Smithsonian Paleontologist: Nick Pyenson appeared first on Smithsonian Insider.

Join Dr. Elizabeth Cottrell as she explores the volcanoes of Alaska’s Western Aleutian Islands.

The post Smithsonian volcanologist Elizabeth Cottrell explores Alaskan Volcanoes appeared first on Smithsonian Insider.

Visits to the Smithsonian's National Zoo just became a little bit sweeter with the arrival of a new honeybee colony. With a hive made of glass in the Zoo's Pollinarium and full access to the outdoors, these bees are showing off the wondrous ways of their world.

The post Honeybees fascinate visitors at the National Zoological Park appeared first on Smithsonian Insider.

For the first time researchers from the Smithsonian, South Dakota State University and the University of Nebraska described the immature stages of the switchgrass moth, first collected in Denver in 1910.

The post Potential biofuel pest, the switchgrass moth, under renewed scrutiny of entomologists appeared first on Smithsonian Insider.

Smithsonian plant physiologist Bert Drake has studied one wetland's response to climate change for more than two decades. He gives a tour of the field experiment and explains some of the findings.

The post On the Chesapeake Bay, Smithsonian plant physiologist Bert Drake has been studying one wetland’s response to climate change for more than two decades. appeared first on Smithsonian Insider.

The post Community ecologist Sunshine Van Bael explains her work in Panama with leafcutting ants appeared first on Smithsonian Insider.

Can a tendency to get distracted lead to a career in science? It did for paleoecologist Conrad Labandeira. Working on his family's farm, he would find himself falling into a study of insect life in the fields. "If you go after what interests you," he says, "the rest will always fall into place."

The post Smithsonian paleoecologist Conrad Labandeira talks about how he became a scientist and why he loves his work appeared first on Smithsonian Insider.

Residents of the southeastern United States might occasionally come across an oddity along a barbed-wire fence: a series of insects, mice or even small birds […]

The post Tiny, fierce and disappearing: breeding program aims to help the loggerhead shrike appeared first on Smithsonian Insider.

The National Ecological Observatory (NEON) is a large-facility project managed by NEON, Inc., and funded by the National Science Foundation (NSF). NEON is a continental-scale […]

The post NEON begins to monitor changing ecology of U.S. appeared first on Smithsonian Insider.

With net in hand and eyes peeled, Mauren Turcatel spent two-weeks last October chasing blood-thirsty predators through the Amazon jungle of Brazil. One-by-one they appeared […]

The post Blood-thirsty jungle horse-flies catch big chill from Smithsonian entomologist appeared first on Smithsonian Insider.

Profound ideas don’t need to be complicated. A simple cube made of aluminum tubing, a centerpiece of a new exhibit “Life in One Cubic Foot,” […]

The post From Rochester to Polynesia, a simple cube unveils Earth’s dazzling biological diversity appeared first on Smithsonian Insider.

The unit-cell reduction described by Selling and used by Delone (whose early publications were under the spelling Delaunay) is explained in a simple form. The transformations needed to implement the reduction are listed. The simplicity of this reduction contrasts with the complexity of Niggli reduction.

Experimental electron-density studies based on high-resolution diffraction experiments allow halogen bonds between heavy halogens to be classified. The topological properties of the electron density in Cl⋯Cl contacts vary smoothly as a function of the inter­action distance. The situation is less straightforward for halogen bonds between iodine and small electronegative nucleophiles, such as nitro­gen or oxygen, where the electron density in the bond critical point does not simply increase for shorter distances. The number of successful charge–density studies involving iodine is small, but at least individual examples for three cases have been observed. (a) Very short halogen bonds between electron-rich nucleophiles and heavy halogen atoms resemble three-centre–four-electron bonds, with a rather symmetric heavy halogen and without an appreciable σ hole. (b) For a narrow inter­mediate range of halogen bonds, the asymmetric electronic situation for the heavy halogen with a pronounced σ hole leads to rather low electron density in the (3,−1) critical point of the halogen bond; the properties of this bond critical point cannot fully describe the nature of the associated inter­action. (c) For longer and presumably weaker contacts, the electron density in the halogen bond critical point is only to a minor extent reduced by the presence of the σ hole and hence may be higher than in the aforementioned case. In addition to the electron density and its derived properties, the halogen–carbon bond distance opposite to the σ hole and the Raman frequency for the associated vibration emerge as alternative criteria to gauge the halogen-bond strength. We find exceptionally long C—I distances for tetra­fluoro­diiodo­benzene molecules in cocrystals with short halogen bonds and a significant red shift for their Raman vibrations.

Using mineralogical data, it is demonstrated that chemical simplicity measured as an amount of Shannon information per atom on average corresponds to higher symmetry measured as an order of the point group of a mineral, which provides a modern formulation of the Fedorov–Groth law.

Yaya Wang
Apr 7, 2020; 133:jcs228072-jcs228072
REVIEW

The explosive growth of information technology is having a profound impact on our lives.

Recent strides in biotechnology offer the promise of new and innovative applications -- from edible vaccines to protein-based electronics components.

The National Academies have bestowed the title of Education Fellow in the Life Sciences to 42 educators around the country who successfully completed a summer institute aimed at fostering innovative approaches to teaching undergraduate biology.

Long-term population trends for some North American pollinators -- bees, birds, bats, and other animals and insects that spread pollen so plant fertilization can occur -- are demonstrably downward, says a new report from the National Research Council.