Smithsonian @NMNH director & paleobotanist. Works with artists to visualize extinct landscapes. [Pers/Prof account, opinions my own]

Washington, DC
Joined September 2010
Kirk Johnson retweeted
Just a reminder that the 2009 Leaf Manual is available open access ! Use it and enjoy the leaves. 🍃🌿🍂 repository.si.edu/handle/100…
NEW Now available open access. Manual of Leaf Architecture. By Beth Ellis, Douglas C. Daly, Leo J. Hickey, Kirk R. Johnson, John D. Mitchell, Peter Wilf, Scott L. Wing. Cornell University Press and New York Botanical Garden Press (2009). OA agreement & pdf link below in replies.
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This is what happens when a walrus falls asleep on a surfacing submarine...
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Kirk Johnson retweeted
You should only look at today's Sea Ice for #Walrus Outlook if you are prepared to have your mind blown by the incredible local observations we received this week! arcus.org/siwo #IndigenousKnowledge #BeringSea #Subsistence #SeaIce #Arctic #SIWO
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Walrus attacked ruzzians in Arctica. No one likes ruzzians🗑🇷🇺🚮 #Russia #Fellas #RussiaIsLosing
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Kirk Johnson retweeted
North America about 77 millions years ago
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Preorder this updated edition! With new dinosaurs, color illustrations, and tales from the road, this is the perfect book for any dino-lover! 🦖 buff.ly/3UJVHvu @leafdoctor #dinosaurs #fossils
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Kirk Johnson retweeted
Thanks for watching The Platypus Guardian tonight! What was the highlight of the episode for you? #NaturePBS
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New name, new identity and new website : Welcome to the Institute of Natural Sciences! 🎉 #naturalsciencesbelgium
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Amazing, just amazing
This beautiful and rare example of a wild jaguar in the snow is of Yo'oko in Arizona's Huachuca Mountains in 2017. He was name by students at Hiaki High School at the Pascua Yaqui Pueblo near Tucson. Yo'oko means jaguar in the Yaqui language. This is a good reminder that...1/
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Kirk Johnson retweeted
Big news: USGS scientists & partners have confirmed, with 2 new lines of evidence, that human footprints found in White Sands Nat'l Park show that people lived in North America 21-23,000 yrs ago—much earlier than previously thought! More here: ow.ly/9peJ50PTBGN Imgs: NPS
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Ever wondered what it's like to go inside the vast collection of a natural history museum, or why we keep such vast natural treasures? Well, wonder no more. This terrific, interactive piece by @peterhartlaub explores the collections of @calacademy. Enjoy! sfchronicle.com/projects/202…
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Another surprise visitor to the San Juan islands today! A giant oarfish washed up on Friday Harbor in near perfect condition. Check out those jaws!!
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AMEGH 60(6) presents the obituary of Dr. Sergio Archangelsky. Born in Morocco on March 27, 1931. The family moved to Argentina, where Sergio studied Geology at the @UBAonline His final dissertation topic was Paleobotany, and that was the beginning of his brilliant career.
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The defense mechanism of an armadillo..
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Kirk Johnson retweeted
To fully grasp this summer's frightful heat, imagine 800,000 Hiroshima atom bombs exploding daily. That amount of energy accumulating in the climate system is why July was the hottest month of 1,716 on record. @DiscoverMag @DrJamesEHansen @MichaelEMann discovermagazine.com/environ…
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Kirk Johnson retweeted
#TBT to May of 1909 and the installation of the last stone on the south porch of the museum. 🏛️ A few short months later staff began to occupy the building and move the then 10 million item collections by horse-drawn cart. Credit: @SILibraries, Record Unit 95, Box 33, Folder 4
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Craziest thing you will see today... Stunning upwards lightning above Acatenango Volcano in Guatemala 🇬🇹
Readers added context they thought people might want to know
Correction: the volcano featured in the video is Volcan de Agua. en.m.wikipedia.org/wiki/Volcán_de… It was taken between the Convento Santa Clara and Tanque La Union on a street that runs north-south. Acatenango is west of Antigua Guatemala. Volcan de Agua is south. en.m.wikipedia.org/wiki/Acatenango
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Kirk Johnson retweeted
This slab of fossilized crinoid specimens date from 345-280 million years ago and was collected in Indiana. Displaying the wide variety of shapes and sizes found in this class of extinct echinoderms, this specimen includes 15 different species. Catalog number USNM S 7342
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Shown here are the youngest dated specimens of Harlan’s ground sloth, western camel, western horse, dire wolf, antique bison, and saber-toothed tiger. These fossils are the last known surviving members of their species. Learn more this week in Science: scim.ag/3LR
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Happy #ThrowbackThursday to our arctodus skull fresh from the Bonebed with a modern bear skull for scale!
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