Palaeo After Dark

The gang discusses two papers about archosaurs. The first paper looks at the trends in brain size relative to body size in birds over their entire evolutionary history. The second paper revisits the dinosaur Spinosaurus and adds more information to the debate over whether this animal had a semi-aquatic lifestyle. Meanwhile, James has some villagers he needs to “un-person”, Curt gives alternative definitions to slang, and Amanda just disappears (I’m sure she’ll be fine).

 

Up-Goer Five (Curt Edition):

Our friends talk about thinks they fly and something that moved through the water. The first paper looks at the brains of things that fly. As the body gets bigger, the brain usually gets bigger as well. But sometimes the way in which the brain gets bigger can change. Sometimes the brain gets bigger faster than the body and sometimes it gets bigger slower than the body. When looking at very old things that fly, what they find is that when the body gets smaller, the brain stays larger. This is something that big angry things which are brother and sister to the things that fly did as well. But later things that fly start changing how the brain gets bigger, with some things having their brains get way bigger faster than the body. This is often found in things that fly which are able to talk and use things which can make stuff work.

The second paper looks at an angry animal that some people think may move through the water and other people think those people are wrong. This paper finds more parts of the animal (the part at the end which can be moved up and down or side to side), which can help us better understand what this angry animal might have done. They find that the part at the end can shake to the side really well, which is something we see in animals that can move well through water. They use this to say that this adds more facts that say this thing may have moved through water.

 

References:

 Ibrahim, Nizar, et al. "Tail-propelled aquatic locomotion in a theropod dinosaur." Nature (2020): 1-4. 

 Ksepka, Daniel T., et al. "Tempo and Pattern of Avian Brain Size Evolution." Current Biology (2020). 

Direct download: Podcast_188_-_Bird_Brains_and_Propeller_Tails.mp3
Category:general -- posted at: 3:00am EDT

The gang discusses two papers about unique taphonomic conditions. One paper describes how these strange “train wrecks” of crinoid columnals might have formed, and the other paper models how bone jams in Dinosaur National Park could have formed. Meanwhile, James’s computer has a flux capacitor, Amanda mishears the best new BBC crime drama, and Curt enjoys the chance to talk about Nathan Fillion vehicles.

 

Up-Goer Five (Amanda Edition):

 Today our friends talk about animals with hard parts on their insides. Some of these animals have long arms with lots of parts and look like they sit on sticks. Others have many inside hard parts in place along their backs, and that is where they get their names. The animals with the long arms with lots of parts sometimes break into small pieces when they die. Usually they break into lots of little single round things, or they are very quickly covered up and are found all put together. But sometimes they break into big pieces that look like a train ran into another train. This paper talks about why they do that. They have long, strong bits of stuff like what is found on your knee. This stuff does not break down so easy and sometimes that is why you get these bigger pieces. The other paper looks at animals with hard parts inside their bodies put in a place along their backs, and what happens when these animals die and their hard parts come together in a moving water place. This paper does this by making tiny ones of the hard parts and putting them in a not-real moving water place. They find that these hard parts easily stick together and it explains why some of the these hard parts look the different ways they do once the animals are dead.  

 

References:

 Donovan, Stephen K. "Train crash crinoids revisited." Lethaia

 Carpenter, Kenneth. "Use of scaled dinosaur bones in taphonomic water flume experiments." Die Naturwissenschaften 107.3 (2020): 15-15. 

Direct download: Podcast_187_-_Taphonomy_Train_Wreck.mp3
Category:general -- posted at: 3:00am EDT

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