Jack Horner
@dustydino
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Dyslexic dinosaur paleontologist; Presidential Fellow, Chapman University; MacArthur Fellow; Nat Geo Explorer; TED & TEDx speaker;Jurassic Park & J W advisor.
California, USA
Joined March 2011
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After 13 years Dinochicken Project has reached a threshold. We know how to initiate teeth, alter skull shape, transform wingtip to a 3 fingered hand, and produce a bony tail. Next and final step will likely have to be on an island, with a generous, intrepid donor!!
#dinochicken
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Happy
#NationalDinosaurDay
Mother Maiasaura feeding her babies berries on a bush.. a Doug Henderson pastel.
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Male Deinonychus dancing for female depicted by Doug Henderson for my 2022 Bureau of Mines and Geology calendar, and forthcoming book “Dinosaurs of Montana.”
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Why would a person have ever thought a Spinosaurus was a land based animal hunting fish like a heron when it had pointy, fluted teeth, and a body and skull obviously adapted for obligate, aquatic piscivory? Someone should have had a word or two with the JP-3 advisor..
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Black juvenile Daspletosaurus horneri from the Blackfeet Nation, Montana on display at the Blackfeet Interpretive Center in Browning, Montana for
#blackfossilfriday
#FossilFriday
#BlackfeetNation
#Montana
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Dinosaurs are going to be brought back one way or another! It will happen! At the moment the Dinochicken Project is slowed down on account of complications of the tail, and meager funding, but we are pushing forward nonetheless.
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At the premiere of Jurassic Park in Washington DC on June 9, 1993, my then wife Joann and I walked the red carpet with Michael Crichton and his wife Anne-Marie, and then we were seated directly behind Mohammed and Lonnie Ali. An evening to remember amongst the dinosaur mayhem!
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This
#FossilFriday
I’m reminded of the juvenile Daspletosaurus skeleton we collected and prepared for the Blackfeet Nation some years ago. With its hyperextended opisthotonic neck, the skeleton reveals an in-situ furcula and in-situ hyoids. Blackfeet Heritage Center, Browning, MT
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The first skeleton I ever put together was a saber tooth tiger back in 1971 when I was in college at the University of Montana. It was on loan from California. It still resides in the geology building. No comments about the trousers, it was the early seventies!
#FossilFriday
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40 years ago Bob Makela and I dig up a nest of baby hadrosaurian dinosaurs originally found by Marion Brandvold. Bob and I referred them to a new genus and species of hadrosaur we christened Maiasaura peeblesorum. I arrived at this site today to mark it’s 40th anniversary. :)
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Two theropod teeth, a Spinosaurus and a T. rex. The first, fluted and pointed and adapted for piscivory, and the second, massive with reduced serrations for a bone crushing opportunist. Meat-eating dino’s were diverse, and not all apex predators.
#FossilFriday
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My first dinosaur bone, found 65 years ago, when I was 8. It was my 104th fossil, and first vertebrate. I think it’s the mid section of a hadrosaur humerus. I found it near Dupuyer, MT in the Two Medicine Formation about 60 miles from where I grew up.
#FossilFriday
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In 1978 when Bob Makela and I completed the excavation of what we would name the holotype of Maiasaura peeblesorum, we drove a steel stake into the ground to mark the site. A few years later we reopened the site and made a shocking discovery, its missing left dentary, pierced!
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Twenty five years ago today I met Michael Crichton in the limo that took he & his wife & me & mine to the theater in Washington DC where Jurassic Park premiered. We walked the red carpet together as protesters yelled their negative thoughts about cloning and genetic engineering!
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On July 15, 1993 I accompanied the cast and crew to the Royal European charity premiere of Jurassic Park with Princess Diana. At the Natural History Museum pre-party I led a tour for the cast who were eaten in the movie so they could know their respective nemeses.
#JurassicPark
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20 yrs ago Bob Harmon spotted a bone sticking out a cliff side. Bob walked a mile to camp for a folding chair. He stacked a pile of rocks, balanced the chair on them, and excavated a T. rex metatarsal. So began the 3 year excavation of B-Rex. Photo by Bob Harmon.
#FossilFriday
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For years I’ve been telling people that we paleontologists don’t go out and just dig holes, but rather that we look for fossils exposed by weathering and then dig. This summer I’m going to find a nice spot in the badlands and just start digging. Curious what we’ve been missing..
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A fascinating aspect of the “raptor-like” dinosaurs is the curvature of their hand claws, recurved like the claws of a cat... for scaling their prey, I (cautiously) presume. And, in groups, like... a “distress” of deinonychosaurs? A disruption? A disembowlment?
#fossilfriday
:)
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Digging dinosaurs with Ariana, 25 years ago!
Ariana Richards (JP star) and Jack Horner digging in the Jurassic of MT following the JP premier 1993.
#FossilFriday
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During the summer of 1988, while prospecting with my son Jason, he yells at me that he had found something. I asked if it was a baby, and he said “no!” I said “leave it, find a baby!” Jason yelled back, “no dad, you are going to like this one!” Hypacrosaurus stebingeri Holotype
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Had good, but short visit with the Burke Museum’s Love T. rex skull. The roughness and pits on the dorsal surfaces of the nasals of rex’s continue to intrigue me! Also, the horn-like processes over the orbits so prominent on some specimens, lacking on others. Cool accoutrements!
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Bill Clemens and I, at the Tyrannosaurus rex holotype site on Hell Creek. Bill was a good friend, a highly respected paleontologist, and an all around terrific person!
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When I was 1year old my family took me to the Two Medicine River about 50 miles from our hometown. 40 years later I collected a Daspletosaurus skeleton off the hillside just above the river behind us.. a specimen of Daspletosaurus horneri. Serendipity
#ThrowbackThursday
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For me the coolest fossil is a newly discovered specimen before its clear exactly what it is. Mysterious, and exciting!
#NationalFossilDay
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Some paleo peeps think histology is destructive. This is a tibia of Yoshi Trike, one of 7 bones sectioned for histology. We now know more about this Triceratops than any other. The skeleton remains morphologically pristine! Histology is instructive not destructive!
#FossilFriday
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Admiring the bones of Maiasaura, drinking a Rainier, and considering the future, as well as how to collect skeletal elements piled like pick-up-sticks ... August, 1979
#FossilFriday
#Maiasaura
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Spending an inordinate amount of time sitting in airports, I’ve discovered quite a number of fossils in the marble floors.... today I’m in the John Wayne Airport exploring the Solnhofen Limestone for ammonites and belemnites! Perpetual Paleontologist!
#FossilFriday
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Back in the day, some 20 years ago I had a lot of trouble with pesky baby hadrosaurian dinosaurs (Courtesy of artist Phil Wilson).
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As I pack up to head to Montana for my 60th high school reunion and my 55th consecutive year in the field, I can’t help thinking back to the summer of 1974 when I dug up my first dinosaur from the Judith River Formation. I had just flunked out of college and had no job prospects.
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20 years ago today I confirmed B-Rex (found by Bob Harmon) a worthwhile skeleton to excavate even though we could only confirm 3 bones, a metatarsal, rib and pes phalange... with 50 feet of overburden, and a steep cliff beneath it, everyone admitted it would be a lengthy project!
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One of my favorite dinosaur photos was taken by John Little, an MSU student. Custer T. rex (MOR 008) shows how all it’s teeth are well set, to the gum line, into both its upper and lower jaws. Unset T. rex teeth are likely either taphonomic or apocryphal rather than biologic.
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In 1952, at the age of 6, I collected my first fossils from the Marias River Formation (Colorado Group) near Shelby, MT. A clam named Inoceramus and an ammonite named Baculites. As far back as I can remember, I loved fossils and wanted to be a paleontologist.
#FossilFriday
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It's always hard to visualize the size of dinosaurs until you get them in your hands! Parasauralophus! 😳
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It’s time creationists understood that we scientists are as vein as anyone else. If any one of us could disprove Evolution we’d do so in a heartbeat as we would instantly become the most famous scientist who has ever lived! Ego is proof of evolution!
#evolution
#ego
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Forty five years ago I was hired to work as a preparator for Dr. Don Baird at Princeton University. Dr. Baird gave me an office and an autographed photo of Edwin Drinker Cope to hang on the wall above my desk. That photo has hung on my office wall or sat on my desk ever since.
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One of my all time favorite Triceratops specimens, Juvie Trike 3, discovered by former doctoral student Denver Fowler. Note the posteriorly curved orbital horns, one of a couple noteworthy ontogenetic characteristics typifying youngsters. Neotenic juveniles!
#FossilFriday
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Currently in the Witte Museum, San Antonio! Gorgeous exhibits!
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These small raptorial dinosaurs with recurved claws and bladed, serrated teeth, defy the notion that a dinosaur apex predator needs to have been large. Just imagine, just one of these clinging to your back, slashing and feeding on you while you thrashed helplessly.
#FossilFriday
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After 10 years of research (Dinochicken Project), the evolution of the avian tail has been revealed! Published today in the Proceedings of the National Academy of Science: “Nonpathological inflammation drives the development of an avian flight adaptation.” Rashid et al, 2023
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I’m often asked what I have against sauropods. When it takes 4 people to lift one jacketed rib, I’d think it would be obvious! Dinosaur skeletons that fit in a quart-size zip lock bag are so much more accessible... 1992 MOR field crew, Wyoming
#FossilFriday
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Cute little dinosaur I found at Oosh, Mongolia in 2005, published in 2011 with my former student Albert Prieto-Márquez and former post doc Bolor Minjin. Finding cool fossils is a thrill but publishing with former students and post docs is an honor much greater than any award.
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JP-III director Joe Johnston in the field with an articulated juvenile Edmontosaurus he discovered back in June of 2004. Funny how edmontosaur skeletons are most often found in river channel sandstones as opposed to river bank mudstones
#FossilFriday
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Reminding everyone out in the field not to bypass anything that you cannot ID as some really cool stuff looks like junk when you first find it. This is what we saw of the Afternoon Delight, < 2 foot long, baby Triceratops skull found in 2006. Check out everything! :)
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The 6 inch (15 cm) long skull of a baby Hypacrosaurus stebingeri from Montana that has yielded evidence of dinosaur proteins, chromosomes, and chemical markers of DNA. Congratulations to former doctoral students Alida and Mary. Excellent
#FossilFriday
!
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Segmented frill don’t the tail of an Edmontosaurus, from the Hell Creek Formation, Montana. Dinosaurs had cool accoutrements!
#fossilfriday
#dinosaursarecool
#montana
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The best thing you can do with a dinosaur egg is to bust it open and look inside! No embryo, no problem, glue is cheap! :)
#FossilFriday
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Extremely proud of my two former Master’s students Greg Erickson and Pat Druckenmiller, who led the research in Alaska showing that some dinosaurs lived their lives in high latitude environments where it was dark four months of the year!
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Our legendary Field Crew Chief Bob Harmon has died peacefully in his home. His legacy and influence will be known for many generations to come. Bob found important specimens, extracted heavy and complex specimens, taught us all how to “git’r done,” and most of all, to be kind!
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A puzzle.. why juvenile Triceratops had such prominent triangular epoccipitals around the borders of their shields, and why these bones changed shape, and flattened against the shields as the animals grew to adulthood. Do similar changes occur in other ceratopsians?
#FossilFriday
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Hadrosaur feet have always puzzled me especially in contrast with the feet of theropods and primitive ornithopods. Wide, short toes make no sense to me. I always liked the idea of them being semi-aquatic, but short and wide seem more camel-ish. abstruse mystifying
#FossilFriday
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Epi-ossifications on the rims of Triceratops shields, including on juveniles, are intriguing display accoutrements. Juvenile Triceratops from the Afternoon Delight Site. Reconstruction by Michael Holland
#FossilFriday
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Hadrosaur carcasses must have been great hiding places for fishes during the Cretaceous. A beautifully preserved primitive sturgeon, in the belly cavity of a Brachylophosaurus skeleton. Too bad for the sturgeon that it was an aggrading river...
#FossilFriday
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Top photo, Rainbow Butte in 1965 where John Ostrom discovered Deinonychus in 1964. The quarry was secured prior to completion on account of overburden. I had a crew led by Des Maxwell reopen the site 30 years later, and invited John back to oversee its completion.
#FossilFriday
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We will never have too many specimens of any species of dinosaur! There is so much to know about their ontogeny, phylogeny, taphonomy, ecology, evolution, etc.
We have many Triceratops yet every single new one found is as exciting as the last! More data, more insights!
#dinosaurs
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Hanging out in an Apple store in Brooklyn, NY, with a young Parasaurolophus... going out soon to see what other dinosaurs are roaming the streets of this Williamsburg neighborhood.
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How many rexes constitute enough to make a girl smile?
#FossilFriday
#SiebelDinosaurComplex
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I’m not into mosasaurs but I do like to use them to show the evolutionary modifications to the humerus, ulna and radius, and their cool hand flippers. Although only having 3 digits, I’d bet the arms and hands of Spinosaurus we’re headed in a similar “direction.” :)
#FossilFriday
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Baby dinosaurs are always fun to think about, but baby tyrannosaurs are especially fun to imagine, a tiny little critter no bigger than a small cat destined to grow to 30 feet in length! 🦖
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Reminiscing on
#FossilFriday
about Bob Makela and I excavating the holotype skull of Maiasaura and the nest of 15 baby Maiasaura back in 1978. What a week that was, and what a cool thing that he and I got to publish our first paper in Nature! Fun way to start a career! :)
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Back to the wonderful world of dinosaur bone histology where more often than not I exclaim, “Whoa! What..... is going on here?!” The crazy, super fibered, metaplastic, caudal vertebra of an ankylosaur..
#FossilFriday
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Tyrannosaur vert weathering out of the Judith River Formation. Doesn’t matter what a person finds, every identifiable vertebrate fossil weathering out in the badlands is exciting to find.
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Interesting to note the contrasts in the structural patterns of dinosaur tooth enamel. Hypacrosaurus, Triceratops, and Tyrannosaurus.
#FossilFriday
#dinosaurs
#dinosaursaresupercool
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In 1975 when I got my first job as a preparator for Don Baird at Princeton University’s Natural History Museum, my first duty was to reconstruct the foot of a sauropod. A person learns a lot as a preparator. I learned I didn’t like sauropods..
#ThrowbackThursday
#FossilFriday
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Today on
#NationalFossilDay
I’d like to thank all the amateur collectors who keep notes and donate their good specimens to museums. This was my collection from age 13, most of which is now in collections at the Yale Peabody (donated to Princeton) or the Museum of the Rockies.
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Tyrannosaurs don’t look like much when you first find them. Shattered, splintered leg bones, and chunks of porous, trabecularized vertebrae. At this stratigraphic level, with Probrachylophosaurus, it’s likely new, a prospect that belies my mission of consolidation.
#FossilFriday
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39 years ago this hill in Teton County MT was named Frantastic for Fran Tannenbaum the Princeton undergrad who discovered an egg on the hills apex. A year later Bob Makela and I renamed it Egg Mtn after excavating hundreds of eggs and skeletal remains of Troodon and Orodromeus.
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Laying out on a hillside in the foothills of the Rocky Mountains in Montana, is a life-size bronze cast of America’s T. rex skeleton. A reminder of a glorious past obliterated by an inauspicious conjuncture.
#fossilfriday
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Ariana Richards (JP star) and Jack Horner digging in the Jurassic of MT following the JP premier 1993.
#FossilFriday
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Maiasaura, the best know dinosaur! Nests eggs embryos ontogeny coprolites footprints skin impressions population structure histology etc.
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My first book, co-authored with Jim Gorman, beautifully illustrated by Doug Henderson, & published in 1985 by the Museum of the Rockies is my favorite publication even though it was written for very young kids. Some things, like Maia, just propitiate our memories.
#FossilFriday
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Happy Birthday Charles! We paleo-geo-bio people are so happy you worked so tirelessly for so many years, and published so very many fascinating books concerning so many different forms, and functions, and mechanisms of life…
#CharlesDarwin
#happybirthdaydarwin
#evolution
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At the premier of Jurassic Park 25 years ago today, my wife and I sat next to Michael Crichton and his wife. The premier was a fundraiser for the Children’s Defense Fund. The theater was filled with dignitaries. Sitting in the seat in front of me was Muhammad Ali...
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Gryposaurus skeleton collected at the Redding Field Station, on display at the Depot Museum, Rudyard, MT
#FossilFriday
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I’ve never had any desire to study dinosaur footprints but a trackway sure is fun to look at, especially those in the Connecticut River Valley. It doesn’t even really matter which dinosaur made them, it’s just the thought... imagining back to that very moment... being with them.
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Mold of a toromorph Triceratops parietal shield (dorsal side) showing massive blood supply.
#FossilFriday
#dinosaurs
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It’s amazing how time flies! 25 years ago talking to Stan Winston, Jerry Molen, and Steven Spielberg about dinosaurs...
#JurassicPark
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Pachycephalosaurs have some truly weird cranial bone histology, often locally packed with fibers of various origins.
#FossilFriday
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An articulated skeleton in a hard sandstone concretion provides intriguing, vexatious, protracted excitement! Hell Creek Formation, Dawson County, MT
#FossilFriday
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I get a kick out of the catch all explanation that dinosaur tail pathologies are the result of tyrannosaur predation. How about some other possibilities... Fallen trees, intercourse, aggressive displays, other dino’s tripping over one sleeping? 🙂
#FossilFriday
#dinosaursarecool
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Looking at the vertebrate fossils in the Venice Museum of Natural History from Niger, and thinking about the Aptian-Albian fauna’s of North Africa, I was struck by the thought that there must not have been much to eat on land, and the fish must have been exceedingly delectable!
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Troodon chasing Orodromeus Curiously when my Princeton University crew discovered Egg Mountain we were puzzled as to what these two species ate. Some teeth of Orodromeus look like those of Troodon, and visa versa.. we wondered if both could have been omnivorous.
#FossilFriday
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On our trip to Italy last week it was cool to finally see two extraordinary fossils I’d either written or lectured about but not ever seen... the skeleton of Ouranosaurus in Venice and the pygmy elephant skeleton from Sicily, in Rome.
#fossilsaresocool
#dinosaurs
#elephants
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Interesting how long it was that us paleo-peeps argued about whether the nasal horn of a Triceratops was a separate bone or not, the disagreement originating from the fact that juvenile and subadult individuals were virtually lacking from collections until recently.
#FossilFriday
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As the election nears it seems appropriate to make our wishes with a T. rex furcula! 🦖
#FossilFriday
#Trex
#wishfulthinking
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For National Fossil Day, a collage of armored dinosaur osteohistology images. Metaplastic tissues from scutes, tail club, and tail “handle” of nodosaurs and ankylosaurs.
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1979, in the prep lab at Princeton University, reconstructing the skeleton of a nestling Maiasaura peebesorum collected from Montana in 1978. How time flies when you’re having 40 some years of nothing but fun!
#FossilFriday
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Jurassic World, the Exhibition, opening in Paris/Saint-Denis this weekend.
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Thanks to all the fans who attended
#JP25
, especially Saturday evening when I was there to witness the whole affair! Great fun getting together with
@PhilTippett
@LauraDern
@LeDoctor
and our host
@colintrevorrow
Special thanks to Molly and
@UniversalPics
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It’s good to take a few steps backward once in a while to reconsider our basic assumptions about tooth morphologies, function and selective forces.. the straight, fluted teeth of spinosaurs make sense but not the tiny, laterally compressed, slightly recurved teeth of Carnotarus..
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Natural cast of the “second brain” of hadrosaurid Edmontosaurus. Enlarged ganglion, glycogen body, or true second brain, this enlarged area of the dinosaur spinal column located in the sacrum deserves serious, dissertation level research. MOR fossils MOR research
#FossilFriday
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Lutheran minister, and amateur paleontologist, Ken Olson collecting the plesiosaur holotype of Edgarosaurus muddi from the early middle Cretaceous Thermopolis Shale in Montana. Amateur collectors who collect for museums are one of a museums greatest assets!
#FossilFriday
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