Palaeo After Dark

The gang discusses two papers that look at evidence for past behavior in the fossil record using both fossil and modern data. The first looks at the evolution of vibration sensing organs in bird beaks, and the second paper looks at how shark teeth within the genus Otodus changed through time. Meanwhile, the gang spends the first 11 minutes arguing about bagels.

Up-Goer Five (James Edition):

The group look at two papers that look at how different types of face have come about in different groups in order to do or eat different things. The first paper looks at the hard face of animals that fly, especially some that have lots of little spaces inside the hard face that allow them to feel things without touching them. The paper shows that the flying animals that can feel things without touching them are not close family, but that when they do begin to feel things without touching them they end up doing it the same way every time. Also some of the earliest things that could fly could feel things without touching them, so all the different ones that feel things without feeling them may be able to do it because it is something that deep down they have because their oldest family did. The other paper looks at big angry animals that breathe water that are more big and angry. It looks at the teeth to see if as these animals got bigger their teeth changed so that they could eat bigger food. The study actually shows that the teeth did not get better at eating big food, but that the way the teeth change might be because they are growing for longer as the animal gets bigger, and that this same thing might explain why those around today eat such a wide type of foods.

References:

du Toit, C. J., A. Chinsamy, and S. J. Cunningham. "Cretaceous origins of the vibrotactile bill-tip organ in birds." Proceedings of the Royal Society B 287.1940 (2020): 20202322.

Ballell, Antonio, and Humberto G. Ferrón. "Biomechanical insights into the dentition of megatooth sharks (Lamniformes: Otodontidae)." Scientific reports 11.1 (2021): 1-9.

The gang discusses two papers that look at how competition, environment, and biogeography affect macroevolutionary patterns. The first paper looks at the evolution of bird beaks, and the second paper looks at patterns in horse evolution. Meanwhile, James has "some" gin, Amanda practices her "reviewer" skills, and Curt enjoys some last minute "honesty".

Up-Goer Five (James Edition):

Today the group look at two papers that are interested in what causes animals to change their form over time. The first paper looks at animals with hard noses that fly to see what causes the nose to change, especially whether close friends wanting to eat the same food makes them change. The paper studies many different groups of animals with hard noses that fly and found that while some groups do show some sign of changing because close friends want to eat the same food, it is not all parts of the animal that changes and most groups do not show any sign of changing because of it at all. The second paper looks at scared animals that run on one finger to see what caused their legs to change over time. It shows that the scared animals that run on one finger living on different big bits of land had different legs, and that their legs changed when they moved into new places so that they could walk across the different types of land they found.

References:

MacLaren, Jamie A. "Biogeography a key influence on distal forelimb variation in horses through the Cenozoic." Proceedings of the Royal Society B 288.1942 (2021): 20202465.

Chira, A. M., et al. "The signature of competition in ecomorphological traits across the avian radiation." Proceedings of the Royal Society B 287.1938 (2020): 20201585.

The gang discusses two papers that look at interesting new arthropod fossil finds. The first paper is the discovery of a new early arthropod which complicates our understanding of their evolution, and the second paper is a large deposit of trace fossils which could be caused by mass arthropod molting. Meanwhile, James has issues with formatting, Amanda's cat is a butt, and Curt has some important legal disclaimers to share.

Up-Goer Five (Curt Edition):

Our friends talk about some animals with many legs that lived in the water and lose their hard skin a long time ago. The first paper is talking about a new type of these animals from a very long time ago which has a lot of different parts on it which look like parts that are found in different animals from around that same time. It has really long arms and also five eyes. These very different parts that don't look like they go together means that it can tell us a lot about how these animals with many legs that lose their hard skin have changed over time. And then our friends run out of things to talk about.

The second paper looks at marks left in the broken up bits of rock. These marks were probably made by one of these animals with many legs that was in the middle of breaking out of its hard skin. The marks look the animals put their bottoms in the ground as they broke out of their skin. Also, the type of broken up bits of rock leads the people who wrote the paper to think that these animals might be moving to place that is not great to live in in order for them to be safe when they break out of their skin. They find lots of marks in the broken up its of rock all at the same time. This might mean that the animals that made these marks were able to move into these places just to break out of their skin.

References:

Mángano, M. Gabriela, et al. "Paleoecologic and paleoenvironmental implications of a new trace fossil recording infaunal molting in Devonian marginal-marine settings." Palaeogeography, Palaeoclimatology, Palaeoecology 561 (2021): 110043.

Zeng, Han, et al. "An early Cambrian euarthropod with radiodont-like raptorial appendages." Nature 588.7836 (2020): 101-105.

The gang celebrates the end of the year by taking another break to play Fiasco, a crime/noir storytelling game by Bully Pit Games.

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The gang celebrates the end of the year by taking another break to play Fiasco, a crime/noir storytelling game by Bully Pit Games.

Congratulations, your application to relocate to the Mars Incorporated Colony has been approved! Mars Incorporated is the premiere future forward, ever-expanding, corporate city state in the Milky Way Galaxy. We only employ experts whose work is on the cutting edge of future technologies. And we pride ourselves on always pushing against the outer limits of the possible, and we are excited to have you joining our team. When you arrive, a sophisticated group of artificial intelligence units and computationally intensive algorithms will assign you to the position best suited for your skills. Then you will enjoy the true splendor and standard of living that is only possible because of Mars Incorporated.

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"Mars Inc." is a story of greed, chaos, and unlikely revolutionaries.

Music from Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0/

This year, we're peeling back to curtain to give everyone a peak at how we build our holiday fiasco episode. Join us as Curt, James, Amanda, Aly, Brendan, and Antony build up the characters and start forming the main conflicts for our holiday episode, "Mars Incorporated".

The gang discusses two papers that examine the roles of competition, biogeography, and niche evolution in macroevolution. The first paper looks at the expansion of angiosperms and correlates it with the extinction of gymnosperms, and the second paper looks at the complex ways the Great American Interchange affected niches in South America. Meanwhile, Amanda goes for the eyes, James has a device, and Curt gives sound penguin "facts".

Up-Goer Five (Amanda Edition):

Today our friends talk about two papers that talk about how things can act on other things but maybe not really. The first paper looks at green things that don't move. There are two sorts of green things that don't move, pointed ones and paper-like ones. Pointed ones today live in the UP or other high places like big tall places or cold places, or places with bad ground. Paper-like ones live all places and are even the stuff you need to cut in the summer. People think the paper-like ones were better at making it than the pointed ones, so they beat the pointed ones after the time of the big angry animals with no hair and big teeth and so now live in all places. This paper shows that maybe that is part of it, but also maybe it is very hard to see and might be from lots of different things, even things like the world getting cold. (But the paper has a story and says it is maybe most that they were better at making it, which might not be true.) The second paper looks at a time when the high places and low places in the "new half" of the world came together and different things moved high while others moved low. It was thought that maybe things from the high places were better at making it, but looking at the types of green things that the moving things were eating shows that even before the two places came together, the green things were already changing and things could change with them.

References:

Reeves, Jane C., et al. "Evolution of ecospace occupancy by Mesozoic marine tetrapods." Palaeontology (2020).

Lautenschlager, Stephan, et al. "Morphological convergence obscures functional diversity in sabre-toothed carnivores." Proceedings of the Royal Society B 287.1935 (2020): 20201818.

The gang discusses two papers about things with legs…. and the word snake is their name. Honestly, we've had flimsier excuses for a podcast, just go with it. The first paper looks at a specimen of a legged snake, and the second paper discusses potential evolutionary pathways for convergent evolution in a group of penguin like animals closely related to snake birds (Plotopterids). Meanwhile, Amanda's computer is doing just fine, James is otter-ly amazing, and Curt knows when to end on top.

Up-Goer Five (Curt Edition):

Our friends talk about two papers which look at animals with legs. The first is an animal that today doesn't have legs but a long time ago animals like it did have legs, very tiny and weird legs. This first paper talks about a dead body of one of these animals with tiny weird legs from a long time ago which has more parts than most. Most other dead bodies we find do not have much of a head, which is really important for deciding how much these old things from a long time ago are the same as the animals that don't have legs today. This dead body has a head, which is cool. It seems that animals without legs first had heads that look like they are today and then lost their legs.

The second paper looks at animals that usually fly but these animals move through water. Some animals move through the water with their arms, but others use their legs to push them through the water. The ones that use their legs seem to drop into the water from above, while others of these animal that can not fly use their arms to move in the water. However, some older animals use their legs to move in the water and did not fly, so this is hard to say for sure. There are also animals in the past who looked like the animals that do not fly, but they seem to move in the water with their legs, not their arms.

References:

Garberoglio, Fernando F., et al. "New skulls and skeletons of the Cretaceous legged snake Najash, and the evolution of the modern snake body plan." Science advances 5.11 (2019): eaax5833.

Mayr, Gerald, et al. "Comparative osteology of the penguin‐like mid‐Cenozoic Plotopteridae and the earliest true fossil penguins, with comments on the origins of wing‐propelled diving." Journal of Zoological Systematics and Evolutionary Research (2020).

The gang celebrates hitting the milestone of 200 podcast episodes by returning to a topic related to their first episode, sharks. The first paper looks at how shark size has changed through time, and the second paper looks at the different ways whirl-toothed sharks were able to eat their food. Meanwhile, James has ideas about the success of Disney movies, Amanda comes back at the wrong time, Curt quotes the good batman movies, and everyone has real troubles just starting the damn podcast (Podcast officially starts getting on topic at 18:15).

Up-Goer Five (James Edition):

This week the group recognize their two hundred shout sound by looking at some papers that cover an idea that is close to an idea they talked about when they did their first real shout sound (which is not the first actual shout sound). The first paper is looking at how big animals that live in the water and have big teeth get large. It gets lots of teeth and looks at animals that live in the water and have big teeth today as well as some animals that live in the water and have big teeth that lived in the past and are known from their whole bodies in order to work out how big they got from just their teeth. It then asks why they got big, and suggests a number of reasons such as that maybe the need to have big babies made them get big, which made them have bigger babies and made them get bigger still. The other paper looks at some weird animals that live in the water with big teeth that have teeth running down the middle of the mouth rather than around it. It looks at both the teeth and also the rest of the head in a couple of animals and shows that they eaten in different ways, and that some would have used their strange teeth to pull animals with many arms from their hard homes, while others would break the homes of the animals with many arms to eat them.

References:

Tapanila, Leif, et al. "Saws, scissors, and sharks: Late Paleozoic experimentation with symphyseal dentition." The Anatomical Record 303.2 (2020): 363-376.

Shimada, Kenshu, Martin A. Becker, and Michael L. Griffiths. "Body, jaw, and dentition lengths of macrophagous lamniform sharks, and body size evolution in Lamniformes with special reference to 'off-the-scale'gigantism of the megatooth shark, Otodus megalodon." Historical Biology (2020): 1-17.

The gang discusses two papers that look in detail at examples of convergence in the fossil record. The first paper uses multivariate statistics to create an "eco-space" in order to study how ecological roles of marine tetrapods changed over the Mesozoic. The second paper looks at the evolutionary history and functional morphology of sabre-teeth in mammals. Meanwhile, James tries a new flavor, Amanda is bathed in soft focus, and Curt details Superman's side hustle.

Up-Goer Five (Curt Edition):

Our friends talk about two papers that look at how animals change and are changed by the world around them. The first paper looks at the jobs that animals do and how those jobs have changed over time. They look at animals with a hard part in their back and four legs which go back into the water and use some number work to see what job each animal has, and how those jobs change over time. They find that there are many things that can happen in these four legged animals that go back to the water. One cool thing is that when one animal goes away for all time, a new animal can come in that does the old animal's job. But this new animal doesn't do exactly the same job as the old one.

The second paper looks at cats and other animals with long teeth. These cats have usually been put into two big groups because of how these long teeth look and thought that these big groups came about because these cats ate different things. This paper looks at all of these cats and not cat things with long teeth and finds that even inside these two big groups, cats are eating other things a probably doing a lot of different jobs. They find that these long teeth may not be used in the way that we thought they were used, and that cats may have been able to use these long teeth for many different jobs. This is important because getting long teeth is a thing that is older than just cats.

References:

Lautenschlager, Stephan, et al. "Morphological convergence obscures functional diversity in sabre-toothed carnivores." Proceedings of the Royal Society B 287.1935 (2020): 20201818.

Reeves, Jane C., et al. "Evolution of ecospace occupancy by Mesozoic marine tetrapods." Palaeontology (2020).