Smithsonian @NMNH director & paleobotanist. Works with artists to visualize extinct landscapes. [Pers/Prof account, opinions my own]
Joined September 2010
- Tweets 3,387
- Following 1,259
- Followers 3,816
- Likes 427
455 Photos and videos
Kirk Johnson retweeted
3 Sep 2024
Just a reminder that the 2009 Leaf Manual is available open access ! Use it and enjoy the leaves. 🍃🌿🍂
repository.si.edu/handle/100…
14 May 2021
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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Kirk Johnson retweeted
21 Mar 2014
This is what happens when a walrus falls asleep on a surfacing submarine...
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Kirk Johnson retweeted
5 Apr 2019
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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Kirk Johnson retweeted
25 Sep 2023
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Kirk Johnson retweeted
20 Jul 2024
North America about 77 millions years ago
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Kirk Johnson retweeted
3 May 2024
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
19 Oct 2023
Thanks for watching The Platypus Guardian tonight! What was the highlight of the episode for you? #NaturePBS
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Kirk Johnson retweeted
New name, new identity and new website : Welcome to the Institute of Natural Sciences! 🎉
#naturalsciencesbelgium
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20 Oct 2023
Amazing, just amazing
18 Oct 2023
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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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
ALT Human footprints at White Sands National Park. Image credit: NPS
ALT USGS scientist Jeff Pigati examines the layers of sediment while collecting pollen to help establish the age of the footprints. Image credit: NPS
ALT Scientists working in and near a trench at White Sands National Park, a sandy landscape with distant mountains in the background. Photo credit: NPS
ALT USGS scientists Kathleen Springer and Jeff Pigati work at the White Sands site, lying on the ground with their faces close to the ground. Photo credit: NPS
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Kirk Johnson retweeted
29 Sep 2023
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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Kirk Johnson retweeted
24 Sep 2023
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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Kirk Johnson retweeted
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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Kirk Johnson retweeted
5 Sep 2023
The defense mechanism of an armadillo..
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Kirk Johnson retweeted
19 Aug 2023
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
18 Aug 2023
Craziest thing you will see today...
Stunning upwards lightning above Acatenango Volcano in Guatemala 🇬🇹
Community note
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
18 Aug 2023
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
ALT A large rectangular fossil displays 15 species of crinoids. The fossil matrix is a sandy brown and the crinoids are scattered across it. Some are shaped like flower buds, while others have a twisted helix shape that is reminiscent of DNA.
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Kirk Johnson retweeted
17 Aug 2023
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
ALT (Clockwise from top left) Harlan’s ground sloth (Paramylodon harlani), western camel (Camelops hesternus), western horse (Equus occidentalis), dire wolf (Aenocyon dirus), antique bison (Bison antiquus), and saber-toothed tiger (Smilodon fatalis)
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Kirk Johnson retweeted
17 Aug 2023
Happy #ThrowbackThursday to our arctodus skull fresh from the Bonebed with a modern bear skull for scale!
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