Episode 71 is all about Leaellynasaura, a polar ornithischian that may have burrowed to keep warm.

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In this episode, we discuss:

• The dinosaur of the day: Leaellynasaura
• Name means “Leaellyn’s lizard”
• “saura” ending is feminine (like Maiasaura)
• Small, herbivorous ornithischian
• Described in 1989, and named after Leaellyn Rich, the daughter of the two paleontologists (Tom Rich and Patricia Vickers-Rich) who found the fossils
• Found in Dinosaur Cove, Australia
• Lived in the Cretaceous
• Type species is Leaellynasaura amicagraphica
• The name amicagraphica means “friend writing” and is in honor of the Friends of the Museum of Victoria and the National Geographic Society
• Found two nearly complete skeletons and two fragmentary skulls and some teeth
• The holotype is of a juvenile
• It was a polar dinosaur that lived in the Antarctic Circle (at the time Victoria, Australia was in the Antarctic Circle)
• Much warmer in the Cretaceous than today, though there were long days and long nights depending on the time of year
• Dinosaur Cove is a fossil bed that was named in 1980. Other dinosaurs found there were specimens of Atlascopcosaurus and an unnamed dinosaur related to Allosaurus
• In 2015 the land next to Dinosaur Cove was put up for sale. Greg Denney, an amateur dinosaur fossil hunter, his family has owned the property for decades but he said someone else needs to take it to the next level and build a museum (with a couple million dollars)
• Leaellyn was 12 years old when they named the dinosaur
• In an open letter to Ranger Rick magazine, Leaellyn Rich wrote, “When I was two, I had a book called My Little Dinosaur. It was about a boy who found a live dinosaur in a cave near his house. I started wanting a dinosaur too. My dad worked with dinosaurs in a museum…so I asked him to get me one. [You] can just imagine how I felt when I first saw the fossils of my very own dinosaur. Thanks Mum and Dad!
• Her father said, “I never promised her a living one. But she got one, even though she had to wait for it” (waited 10 years)
• Tom and Patricia have been married and partners in science for 50 years
• They also discovered another dinosaur, Timimus, named after their son Tim
• Leaellynasaura was about 6.5 to 10 ft (2-3 m) long and 2 ft (60 cm) tall at the hips
• Bipedal, warm-blooded
• Lived in temperatures between 21 and 50 degrees F
• Grew quickly during first 3 years, then grew more slowly after (based on histological studies of femurs found in 1999, after the initial discovery)
• May have grown first in early years to more easily regulate body temperature and then once it was large enough, didn’t need to grow during tough times
• Probably had skin and hair-like filaments
• Leaellynasaura had a really long tail (more than 70 vertebrae in its tail and some scientists think it was 75 percent of its body length); possibly used the tail for display though it’s unclear
• Has the proprotionately longest tail of all known ornithischians
• Flexible tail
• Tail may have been fluffy (wrap around body for warmth)
• May have burrowed, since three fossilized burrows were found in Dinosaur Cove in the late 2000s (maybe to help stay warm)
• Leaellynasaura may have lived for weeks or months (up to 4 months) at a time in the dark
• Still got light from aurora (snow reflecting light displays) and the moon
• Probably didn’t hibernate, though don’t know for sure. Scientists used to think that because the “growth rings” in its bones changed in thickness it slowed its metabolism down in the winter to hibernate, but scientists have since found similar growth ring fluctations in dinosaurs that lived in tropical areas (wouldn’t have had to hibernate), so it’s unclear whether or not Leaellynasaura hibernated
• It had large eyes and large optic lobes, though that may be attributed to a juvenile, not adapting to low-light conditions
• Lived among many streams and rivers and forests of conifers and ginkgoes
• Ate low-lying plants like ferns and horsetails
• May have traveled in small herds
• Leaellynsaura is on 5,000 collector coins as part of Perth Mint’s Australian Age of Dinosaurs series
• Can see Leaellynasaura in a Dinosaur Petting Zoo in Australia (features dinosaur puppets that kids can touch as they learn about the dinosaurs)
• From July 27 2015 until July 2016, there is an exhibition called Wildlife of Gondwana at the National Wool Museum in Geelong that shows a lot of polar dinosaurs, including Leaellynasaura (exhibition based on the research of Tom and Patricia)
• Has been described as a hypsilophodontid, an iguanodontian, and an ornithischian
• Unclear where in Ornithopoda Leaellynasaura belongs
• Ornithopods are ornithischians that started small and became larger and populous, especially in the Cretaceous
• Ornithopoda means “bird feet”
• They had three-toed feet (early ones had four toes), and a beak
• They lived on all 7 continents
• They had still tails to help balance, and later ornithopods grazed on all fours and semi-quadrupedal
• They were great at chewing, like a modern cow
• Fun Fact: Claws can tell you a lot. According to an article by Stephan Lautenschlager published in the Proceedings of the Royal Society titled “Morphological and functional diversity in therizinosaur claws and the implications for theropod claw evolution,” different therizinosaurs likely used for claws for different purposes. He looked at three different uses of a claw: scratching and digging, hooking and pulling, and piercing.Basically it boiled down to shorter/wider claws being good for pretty much all three activities. But longer/thinner claws probably couldn’t have been used for scratch-digging. So we can get a little bit of an idea about their behavior just by looking at their claw shape.