The Rock Gangue

It's Fossil Friday! Behold the dazzling colors of an iridescent ammonite (Placenticeras intercalare). A relative of today’s squids, this ammonite lived some 80 million years ago near what is now Alberta, Canada. This fossil’s spectacular coloration is the result of millions of years of high temperatures and pressures. As these forces acted on nacre in this ammonite’s shell, it was transformed into a gemstone known as an ammolite. Along with amber and pearl, ammolite is one of only a handful of gems made by living organisms. You can spot this rare specimen in the Louis V. Gerstner, Jr. Collections Core in the Museum’s Gilder Center.

We're back in The Pitt for season 2 and rooting for our faves as they embark on another long day of emergency medicine at Pittsburgh Trauma Medical Center. Here's some fan art of Drs. Robby, Whitaker, King & co to keep you going til Friday.

(mild spoilers! tap on the attribution to go to the original post :)

@romaincrisis:

@possumtion:

@eyes-of-nine:

@aeagleart:

@trickytrick:

@starspangledsteeve:

@alex-moriarty:

@kitchen-soup:

@bompeii:

@sqwampy:

@kirsssche:

@stellar-waves:

@333ml:

@summerscaries:

@raspberryazalea:

@reesemh:

@evelina-maar:

@searching4aname:

@ollhys:

@yousharknotpass:

Unlike Earth, where sunsets are red and orange due to the scattering of shorter blue wavelengths by our atmosphere, Mars has an extremely fine dust that scatters blue light more efficiently near the Sun.

So during sunset on Mars, the sky turns reddish-brown while the area around the Sun glows a soft blue. It’s the opposite of what we experience on Earth.

NASA’s rovers have captured this eerie sight

May I present the best apple:

Last week, the Trump administration quietly released a sweeping new federal rule that would use funding threats to force institutions across the country to reject transgender people. The 400-page proposed regulation would codify the administration's anti-trans executive orders into binding federal policy, imposing a blanket prohibition on federal funds going toward "gender ideology"

The proposed rule, formally titled "Regulation for Federal Financial Assistance," rewrites the government-wide framework governing all federal grants across every agency. Among its most consequential provisions, it requires that before a federal grant recipient can receive money, the award must pass a "pre-issuance review" conducted by a political appointee—not a career expert or peer reviewer—to ensure it is "consistent with applicable law, Federal agency priorities, and the national interest." The regulation explicitly instructs these appointees to screen for "denial by the recipient of the sex binary in humans or the notion that sex is a chosen or mutable characteristic." [...] An institution that acknowledges transgender people exist—through its policies, its training, its healthcare, its bathroom access, its HR procedures, its name-change processes—could be deemed to "deny the sex binary" or to “support the notion that sex is mutable” and have its federal funding blocked.

Still can’t get over just how small this species is.  Asplenium trichomanes subsp. quadrivalens.

This species prefers acidic rocks typically; but this smaller subspecies is really only associated with dolostone outcroppings that retain moisture or stay fairly wet. The divisions of the maidenhair spleenwort is really not by size necessarily, but is associated directly with substrate and separation by long distances between prefered habitats. Although this speciation event isn’t traditional allopatric speciation(speciation by large scale geographic divergence and separation) this species is definitely one exception that had been funnelled under that cause, micro-allopatric speciation for quite some time due to the presence of this species in many countries that span the northern hemisphere of the globe. The truth later was found that Asplenium trichomanes subsp. quadrivalens was far more rare overall than its acidic sandstone loving lineage, and it was more associated with North Eastern North America. Thus it was due to edge niche shift in a place that shared both habitats(like RRG for example). This then referred this speciation event to  Parapatric Speciation; the specific way it has been phrased is really “Gradual speciation by habitat splitting” 

The more common acidic/sandstone loving lineage is referred to now as A. trichomanes subsp. trichomanes.