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).
The gang discusses two papers about interesting finds in the bones of fossil vertebrates. The first paper looks at the evolution of bony parts in early fishes, and the second paper shows a fascinating example of ontological change in a species of sauropod dinosaur. Meanwhile, Amanda’s best ideas are ignored, James has unconventional bread opinions, Curt offers some advice, and everyone spends their time just negging a baby.
Up-Goer Five (Curt Edition):
Our friends look at two papers that look at things with a back. The first paper looks at the hard parts that make up these early things that lived in the water. Many people think that some of these early things do not have inside hard parts that are the same as the inside hard parts of other things that are around today which move in the water. However, this paper looks at one of these early things and finds that it does have these inside hard parts. And it turns out, that things that appear after it then lost these inside hard parts. What we thought before was wrong; these inside hard parts seem to have appeared and disappeared in these early things that move through the water.
The next paper is about a baby that is not good to look at. The baby is of a very big animal with four legs and a long neck. This is the first time we have seen a baby of this animal and it looks very strange. The eyes of the baby are more forward than the eyes of the grown up, meaning that the eyes must move as the baby gets older. This is not something that anyone thought would happen before we found this baby. There is a lot to talk about with this baby, but our friends just talk about how weird it is.
References:
Kundrát, Martin, et al. "Specialized Craniofacial Anatomy of a Titanosaurian Embryo from Argentina." Current Biology (2020).
Brazeau, Martin D., et al. "Endochondral bone in an Early Devonian ‘placoderm’ from Mongolia." Nature: Ecology and Evolution (2020).
The gang discusses two papers that investigate niche partitioning and the ecological impacts on bird beak evolution. Honestly, this podcast is just a grab bag of different topics loosely connected together as an excuse for James to continue to espouse his beliefs on pies. The gang discusses one paper about a long necked reptile and another paper about beak morphological evolution in Aves. Meanwhile, Amanda is a Samurai Jack fan apparently, James likes his papers short, and Curt kills an old joke.
Up-Goer Five (Curt Edition):
Our friends look at two papers that look at faces. The first paper looks at this strange thing that lived in water and had a very long neck and small head. When people found these strange things, there was always a big one and a small one. Most people thought the small one was just a baby of the big one. This paper shows that the small ones were not babies, and in fact they actually lived in a different way from the big one. This means there was more than one of these strange things living in the same place at the same time, and the fact that they lived in different ways may be way they could have been able to stay so close without causing the other ones to die out from there not being enough food.
The second paper looks at the faces of animals that fly. These faces change a lot because the face is what they use to eat. Some of these animals that fly seem to have faces that look like they are that way because of the things they eat, but others of these animals do not seem to do this. This paper studies lots of these things that fly and looks at how they are brother and sister to each other. What they find is that groups that eat a few types of things have fast changing faces, while other groups do not have fast moving faces. In short, why some faces change and others do not seems to be something that does not have an easy answer and that is cool.
References:
Felice, Ryan N., et al. "Dietary niche and the evolution of cranial morphology in birds." Proceedings of the Royal Society B 286.1897 (2019): 20182677.
Spiekman, Stephan NF, et al. "Aquatic Habits and Niche Partitioning in the Extraordinarily Long-Necked Triassic Reptile Tanystropheus." Current Biology (2020).
The gang discusses two papers that look at the wealth of information left behind on fossil bones which can let us know about the many organisms which worked to break down and decay dead animals. These feeding traces give clues to the presence of animals that might not easily fossilize. Plus, this topic is an excuse for James to suggest two papers that involve dead dinosaurs. Meanwhile, Curt starts a business, Amanda goes prepper, and James wonders about the taphonomy of Shrek.
Up-Goer Five (Curt Edition):
Our friends talk about things that eat the dead. These two papers look at marks on the hard parts of dead angry animals that are caused by other animals eating the dead bodies. The first paper looks at lots of different marks from many different small animals. These marks let us know that these animals were living there, even when we don't have good bodies of those animals. We can learn a lot about the different types of animals from these marks. The second paper looks at marks that they think were made by small warm animals with hair.
References:
McHugh, Julia B., et al. "Decomposition of dinosaurian remains inferred by invertebrate traces on vertebrate bone reveal new insights into Late Jurassic ecology, decay, and climate in western Colorado." PeerJ 8 (2020): e9510.
Augustin, Felix J., et al. "The smallest eating the largest: the oldest mammalian feeding traces on dinosaur bone from the Late Jurassic of the Junggar Basin (northwestern China)." The Science of Nature 107.4 (2020): 1-5.
The gang discusses two papers that use the trace fossil record to give us a more detailed understanding of the impacts of mass extinctions. Meanwhile, Curt has a new CSI, Amanda has too many synapsids, and James “understands comedy”.
Up-Goer Five (Curt Edition):
Our friends talk about the marks that feet make on the ground and how these marks can tell us about things that died when really bad things happened. They look at two times in the past that a lot of stuff died all of a sudden. The first paper looks at when some big angry animals that are aunts and uncles to things with hair lived. This is from a place where there is a lot of dead things and also foot marks. The paper shows that the death of these big angry animals can be seen if you look for the dead parts or if you look at the feet marks.
The second paper looks at a time when a huge rock hit the ground and nearly killed everything. This paper looks at how foot marks and other marks in the ground changed before and after the rock hit at the place where the rock hit. What they find is that, the rock hitting caused there to not be a lot of marks because things were probably dead. But after a pretty short time, there were a lot or marks again and those marks were not just at the top but also showed that animals were moving up and down as well in the ground.
References:
Marchetti, Lorenzo, et al. "Permian-Triassic vertebrate footprints from South Africa: Ichnotaxonomy, producers and biostratigraphy through two major faunal crises." Gondwana Research 72 (2019): 139-168.
Rodríguez-Tovar, Francisco J., et al. "Rapid macrobenthic diversification and stabilization after the end-Cretaceous mass extinction event." Geology (2020).
The gang discusses two papers about the ecological data that we can learn from looking at trace fossils. The first paper looks at a unique ancient crocodilian behavior, and the second paper shows similar shore bird behaviors over the course of tens of millions of years. Meanwhile, James is full of bones, Amanda is honored, and Curt loves Hanna Barbera.
Up-Goer Five (Amanda Edition):
Today our friends talk about foot marks. They talk about the foot marks of two-legged animals with no hair and no teeth that can usually fly, and also the foot marks of two-legged animals that are usually four-legged, with big teeth and long faces and hard skin. The foot marks of two-legged animals with no hair or teeth that can fly are fun because they look at ones that have been known about for a very long time, but no one has ever done anything with them. They are not so old, and they look at them and some ones that are very very old, and find that they have the same sort of groups of foot marks, even though one is very old and very far away from the other one, which is much less old. They also say that you can see the same sort of groups of foot marks today, too. The other foot marks are from animals that are usually four-legged, but this one is two-legged. That is not so weird, because they were two-legged a long, long time ago. But this one is two-legged after we thought they all were four-legged. That's weird because at the same time there were very large angry animals with big teeth and no hair, which people thought maybe made it so these other usually four-legged animals with big teeth and long faces and hard skin couldn't be two-legged anymore. Maybe that isn't really the case, because it doesn't look like these foot marks were made by something that is only going two-legged for a short time.
References:
Lockley, Martin, et al. "Bird tracks from the Green River Formation (Eocene) of Utah: ichnotaxonomy, diversity, community structure and convergence." Historical Biology (2020): 1-18.
Kim, Kyung Soo, et al. "Trackway evidence for large bipedal crocodylomorphs from the Cretaceous of Korea." Scientific Reports 10.1 (2020): 1-13.
The gang discuss two papers that describe unique animal fossils which have been known but haven’t (until now) been formally described. The first is “Collins Monster”, a lobopod from the Cambrian, and the second is a fossil dolphin which is similar to an orca. Meanwhile, James rehabilitates some dolphins, Amanda saw a thing, and Curt witnesses true beauty.
Up-Goer Five (Amanda Version):
Today our friends talk about a strange animal with cute legs and big parts that go to a point, and a really big animal that used to have hair that looks like an animal with no legs but actually does have legs. Both of these things have been known about for a long time, but no one gave them a name. They were used to figure out the family tree of animals, but never had a name. These papers give them a name, which is a very important thing. The strange animal with cute legs and big parts that go to a point is very close to other strange animals with cute legs that we have talked about before. The paper does put them in a different box than we are used to seeing, which we talk about a little and find maybe a little strange. The big animal that used to have hair and looks like an animal that has no legs but it actually has legs looks like it is close to one animal that had hair and looks like it has no legs, which shows that these things show up many times as time goes on. They also show some family trees, but only one is in the paper, the rest are in the other stuff on the space where people store all their stuff today.
References:
Caron, Jean‐Bernard, and Cédric Aria. "The Collins’ monster, a spinous suspension‐feeding lobopodian from the Cambrian Burgess Shale of British Columbia." Palaeontology (2020).
Boessenecker, Robert W., et al. "Convergent Evolution of Swimming Adaptations in Modern Whales Revealed by a Large Macrophagous Dolphin from the Oligocene of South Carolina." Current Biology (2020).
Hey now, you’re an all-star, get the game on, go play. Hey now, you’re a rock star, get the show on, get paid! All that glitters is a long discussion about Mesozoic eggs. One of the papers we discuss suggests that the evolution of hard calcification in dinosaur eggs might have evolved independently multiple times. The second paper tries to determine the origins of a cryptic large soft-shelled egg. Meanwhile, James vents on his victims, Curt ruins the fun of Shrek, and Amanda has an egg guy.
Up-Goer Five (Curt Edition):
Our friends talk about two papers that look at the things that small baby animals pop out of. Both papers are from a time when there were big angry animals that some people and all children really love. The first paper asks whether or not the things that these babies pop out of were soft or hard. While most of the things which babies pop out of from these angry animals are hard, hard things are also more able to become rocks than soft things. Also, each of the different types of angry animals seem to make their hard things in different ways. This paper looks at the things that babies pop out of from angry animals that are much earlier than the things we usually see. These angry animals all seem to be popping out of soft things, and since they are not close brothers and sisters, this means that angry animals each came up with different ways to make that things babies pop out of hard.
The second paper finds a very large soft thing that babies pop out of. Given how big this thing is, they have problems finding out what could have made this thing. They don't have a perfect answer, but they think that maybe it could be from an angry thing that lived in the water. The problem here is that the babies may have died if they were in the water while in the thing. However, it is possible to still have the thing that the babies pop out of be a real thing even if the babies then stay in the mom before they pop out.
References:
Legendre, Lucas J., et al. "A giant soft-shelled egg from the Late Cretaceous of Antarctica." Nature (2020): 1-4.
Norell, Mark A., et al. "The first dinosaur egg was soft." Nature (2020): 1-5.
The gang discusses two papers that look at important points in the evolutionary history of land plants. The first paper is a review of the available data for the first time plants moved onto land in the Ordovician, and the second paper looks at the impact that the evolution of herbivory had on plant diversity. Meanwhile, James invents a new insect, Amanda reaches out and touches someone, and Curt is impressed by a brief moment of professionalism.
Up-Goer Five (Curt Edition)
Our friends talk about very old green things that grow in the ground and use the sun. The first paper looks at this very old time when green things move from water to the ground. This was a very very very long time ago, and most of what we have that lets us know about these green things are actually the small bits that the green things let go of. This paper looks at what we know about these first green things move onto land, and says that maybe as these green things go to the ground they may have changed the air. Also, the time that these things move onto land is the same time that things in the water become more different.
The second paper looks at when animals started to first eat these green things. The paper looks at changes in the animals that eat these green things, and tries to see if these animals can change how many green things there are. Big animals eat lots of different types of green things, while small animals often eat just a few types of green things. How big the animals appears to change the number of different green things. This means that animals that eat green things can have a strong control on the number of different types of green things.
References:
Brocklehurst, Neil, Christian F. Kammerer, and Roger J. Benson. "The origin of tetrapod herbivory: effects on local plant diversity." Proceedings of the Royal Society B 287.1928 (2020): 20200124.
Servais, Thomas, et al. "Revisiting the Great Ordovician Diversification of land plants: Recent data and perspectives." Palaeogeography, Palaeoclimatology, Palaeoecology (2019): 109280.
The gang discusses two papers about arthropod evolution and development. One paper focuses on the evolution of arthropod segmentation, and the other summarizes research on the development of the insect wing. Meanwhile, Amanda has a beer with no unintended consequences, Curt makes a shocking discovery about marketing, and James goes from 0 to professional in milliseconds.
As we did last time, here are some organizations you can donate to:
https://blacklivesmatter.com/
https://bailproject.org/
https://www.aclu.org/
Up-Goer Five (Amanda Edition):
Today our friends look at small things with many legs and many body parts. The first paper is looking at how these small things with many legs and many body parts first grew the parts they needed to fly. The paper says lots of words about this, but there are two big ideas, saying that these body parts that the body parts these animals needed to fly grew from either the up on the side or down on the side. It turns out that maybe the truth is somewhere in the middle. No, really, they probably grew from both up and down on the side, there was another paper that came out while this one was being worked on that says that, and they talk about it in this paper. The second paper looks at how these animals came to have many body parts, and says how it is important that we look at the things that are very very very dead, as well as the very very very very tiny bits of living things that carry the things our bodies need to know to make stuff.
References:
Chipman, Ariel D., and Gregory D. Edgecombe. "Developing an integrated understanding of the evolution of arthropod segmentation using fossils and evo-devo." Proceedings of the Royal Society B 286.1912 (2019): 20191881.
Clark-Hachtel, Courtney M., and Yoshinori Tomoyasu. "Exploring the origin of insect wings from an evo-devo perspective." Current opinion in insect science 13 (2016): 77-85.
(Editor’s Note: This episode was recorded a month ago. Everyone at Palaeo After Dark stands with the protesters fighting for justice. Black Lives Matter!)
The gang discuss two papers about large mammal-like animals. The first is a Triassic synapsid the size of an elephant, and the second is a mammaliaform from the late Cretaceous of Madagascar. Meanwhile, James has a new technology to discuss, Amanda’s cats get involved in some unique business ventures, and Curt appreciates some choice scale-bar decisions.
https://blacklivesmatter.com/
https://action.aclu.org/give/now
Up-Goer Five (Curt Edition)
Our friends talk about big boys. These big boys are great great great great great great brothers and sisters to things that have hair and are warm. The first of these big boys is the oldest and it lived a long time ago when big angry animals were just starting to show up. This big boy is a REALLY big boy. This big boy shows that not just the angry animals, but a lot of other animals, were getting big at this time. This means that maybe something was happening that made it so getting big was a thing lots of different animals could do.
Our second big boy was living just before a rock killed the big angry animals. The second big boy is not nearly as big as the first big boy, but we look at the others boys with hair it was pretty big. This big boy also has lots of weird things in its hard parts that we usually do not see in animals with hair at this time. This big boy lived in a place that was not a part of all the other land and was surrounded by water. This second big boy is another animal that got big when it came to this place. This place has been away from the land for a very very very long time, and so the animals at this place have been different for a long time.
References:
Sulej, Tomasz, and Grzegorz Niedźwiedzki. "An elephant-sized Late Triassic synapsid with erect limbs." Science 363.6422 (2019): 78-80.
Krause, David W., et al. "Skeleton of a Cretaceous mammal from Madagascar reflects long-term insularity." Nature (2020): 1-7.
Palaeo After Dark is a free biweekly podcast about evolutionary biology and paleontology... over beer. Hosts James Lamsdell, Amanda Falk, and Curtis Congreve engage in long, informal conversations about natural history.
