but how do they KNOW that?

Ceratopsian Month #28 – Vagaceratops irvinensis

Vagaceratops (“wandering horned face”) was originally thought to be a species of Chasmosaurus, but was separated out into its own genus in 2010 after new studies suggested it was much more closely related to Kosmoceratops.

Measuring around 5m long (16’4”), it lived about 75 million years ago in Alberta, Canada – much farther north than its Utahn relative, inspiring its “wandering” genus name. It had a short nose horn, and brow horns reduced down to low bosses, along with a distinctive squared-off frill topped with a row of forward-curving spikes.

Ceratopsid forelimb posture has been a long-standing puzzle in paleontology. While the hindlimbs were clearly held straight under the body, the bones of the forelimbs are a lot more ambiguous, and various different arrangements have been proposed over the years from straight to heavily sprawled and lizard-like.

Yapok

The water opossum (Chironectes minimus), also locally known as the yapok, is a marsupial of the family Didelphidae. It is the only living member of its genus, Chironectes. This semiaquatic creature is found in and near the freshwater streams and lakes in Mexico, Central and South America to Argentina, and is the most aquatic living marsupial.  It is also the only living marsupial in which both sexes have a pouch. 

Springhare

The South African springhare (Pedetes capensis), or springhaas in Afrikaans, is not actually a hare, but a rodent. It is one of two living species in the genus Pedetes, and is native to southern Africa. The East African springhare (Pedetes surdaster) was recognised by Matthee and Robinson in 1997 as a species distinct from the southern African springhare (P. capensis) based on genetic, morphological, and ethological differences. P. capensis from South Africa has fewer chromosomes (2n= 38) than does P. surdaster which has (2n = 40) and some other genetic variations. The East African springhare is found in central and southern Kenya and most of Tanzania.

Ceratopsian Month #25 – Pentaceratops sternbergii

Despite its name, Pentaceratops (“five-horned face”) only had three main facial horns just like most other ceratopsids. The extra two “horns” actually refer to the cheek spikes which protruded out sideways from its face – a feature seen in all ceratopsids to some degree, but especially long and sharply pointed in Pentaceratops.

Living about 76-73 million years ago, its fossils are known from New Mexico and Colorado, USA. A possible second species, P. aquilonius, was discovered much farther north in Alberta, Canada, but this identification is somewhat dubious due to the remains being highly fragmentary.

Multiple specimens have been found, with a full body length of around 5-6m (16’4"-19’8”). One especially large specimen previously identified as Pentaceratops was nearly 7m long (23′), but has since been moved into its own separate genus Titanoceratops.

“Ain’t no party like a Chemistry party because a Chemistry Party don’t stop.”

Her images bring to life the Baikal giant amphipod Acanthogrammarus victorii, a strange, spiny little monster that lives under the icy grip of Lake Baikal. These beasts are among the biggest of their kind and Olga’s photography has captured their otherworldly crimson beauty in great detail and splendor. They roam among ice floes, scavenge on the bottom or even swim through the depths of the lake like red beacons in a dark void.

Neon dream

Alone, the chemicals β-ketoiminato boron difluoride and 4-N,N-dimethylbenzaldehyde don’t look particularly special. But, as Lynn Stevens found, when they’re combined through condensation reactions, they make these fluorescent dyes. Stevens, who is an undergraduate at St. Mary’s College of Maryland, made the dyes as part of research in Daniel T. Chase’s lab, which focuses on making boron difluorides such as these. After purifying her reaction mixture through a column of silica, she was able to separate the orange dye (structure shown) from the green one. The difference between the two is that the orange dye is the product of two 4-N,N-dimethylbenzaldehyde molecules reacting with boron difluoride, while the green dye is the product of a single 4-N,N-dimethylbenzaldehyde molecule reacting with the boron compound.

Submitted by Lynn Stevens and Daniel Chase

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More Chemistry in Pictures and C&EN Stories:

Endless Fractions

This gigantic titanosaur (on display at @amnhnyc) finally has a name of its own! 

Scientists are trying a new, interactive way to understand ocean current data with the help of high-resolution global ocean simulations. In the part of the global visualization shown, the Gulf Stream features prominently. Surface water speeds are shown ranging from 0 meters per second (dark blue) to 1.23 meters per second (cyan).

This video is running at one simulation day per second. A team from our Advanced Supercomputing (NAS) facility at our Ames Research Center has developed a new visualization tool that is being used by researchers to study the behavior of ocean currents. The new visualization tool provides high-resolution views of the entire globe at once, allowing the scientists to see new details that they had missed in previous analyses of their simulation, which was run on our Pleiades supercomputer.

For more information, visit: https://www.nasa.gov/feature/ames/scientists-explore-ocean-currents-through-supercomputer-simulations