 The gang discusses two papers about unique adaptations in the fossil record, the first is a paper about pterosaurs that have opposable thumbs and the second paper talks about burrowing synapsids. Meanwhile, Discord is silencing James, Amanda fact checks, and Curt messes everything up…. like EVERYTHING.   Up-Goer Five (Amanda Edition): Today our friends look at some things that make very old animals that are not close to other animals look like those other animals. First our friends talk about an animal that had a very long ring finger with long skin on it and could fly. This is a pretty early animal that had a very long ring finger with long skin on it. People have thought that maybe animals that had a very long ring finger with long skin on it lived in trees. A new animal was found that had a first finger that can move across from the others, like people have on their hands. This means that this animal that had a very long ring finger with long skin on it could grab onto trees and hold them, which means they probably did live in trees. The second paper our friends look at looked at very old animals that had hair. Some of these are not even really animals that have hair like the ones that live today, because the three hard pieces inside the ear are not all the way in there yet. But these animals that had hair had some things that are like each other, because they had very big hands with heavy hard pieces in them that means they move in the ground. They push the ground around and are found under it. These are the oldest kinds of animals with hair that do this, and they also do some strange things with their hard bits that make up their back. This might be a thing that animals with hair living under the ground just do.   References: Zhou, Xuanyu, et al. "A new darwinopteran pterosaur reveals arborealism and an opposed thumb." Current Biology (2021). Mao, Fangyuan, et al. "Fossoriality and evolutionary development in two Cretaceous mammaliamorphs." Nature (2021): 1-6.

Palaeo After Dark

Podcast 213 - Bringing our C Game

 The gang discusses two papers that talk about T-Rex, and also the interesting way that these papers were discussed in popular culture. The first paper looks at the walking speed of T-Rex, and the second paper estimates how many T-Rex could have lived on Earth at any given time. Meanwhile, James is so very tired, Amanda loves soap, and Curt picks the worst transitions.   Up-Goer Five (Curt Edition): The friends talk about a big angry animal that a lot of people know about. The first paper looks at how quickly that big angry animal could walk. Most animals with four legs / arms all walk about as fast as each other, even if the animals are big or small. Early work had made it seem that the big angry animal may have walked faster than the animals today. These early papers were looking at the foot falls of these big angry animals. This new paper looks at the big long part that comes off the end of these angry animals. The paper says that these big angry animals walked about as fast as any animal today even though they were big and angry and walked in a funny way. The second paper tries to use the parts of these big angry animals that have turned into rocks to try and figure out how many of these big angry animals may have been living at any given time. It looks at how many animals we see around today to do this, and sees that the number of animals may be controlled by how much food the animals need to keep eating. Some animals burn a lot of food which means there can not be as many of them in an area. This means you can use how much food an animal burns to try and figure out how many animals could have been living in an area at any time. So they use this and some other numbers to try and figure out how many of these big animals were around in the past. This also allows them to figure out how many of the big angry animals may have been covered in ground and have their parts turned to rocks and how many were not.   References: Marshall, Charles R., et al. "Absolute abundance and preservation rate of Tyrannosaurus rex." Science 372.6539 (2021): 284-287. van Bijlert, Pasha A., AJ ‘Knoek van  Soest, and Anne S. Schulp. "Natural Frequency Method: estimating the  preferred walking speed of Tyrannosaurus rex based on tail natural  frequency." Royal Society Open Science 8.4 (2021): 201441.

Podcast 212 - Ruining T-Rex

 The gang talks about two papers that look at changes in ecological interactions through deep time. The first paper looks at how ecological networks changed from the Permian into the Triassic, and the second paper looks at how echinoid diversity patterns compare to echinoid predation patterns. Meanwhile, James has some choice words about Elon Musk, Amanda’s stream is torn “into pieces”, and Curt once again would really like to start the second half of the podcast…   Up-Goer Five (Curt Edition): Our friends talk about how animals and things that are not animals can build a place to live together, and how that changes over time. The first paper looks at how the places these animals and not animals build can change when things get really bad. It looks at two places in the past and uses numbers to see how these places change by getting more busy or less busy. They find that before most of the times when lots of stuff died, the places built by these animals and not animals were getting easy to fall to pieces. This is not true for this one time where things go really bad though, which is interesting and means that what was happening when things got really bad must be different. The second paper looks at how a round animal in the water with hard hurt causing parts have changed over time and tries to see if being eaten caused some change. The paper finds that there are some changes that happen when we see these things get eaten, but also a lot of the changes are happening before we see these things get eaten.   References: Petsios, Elizabeth, et al. "An  asynchronous Mesozoic marine revolution: the Cenozoic intensification of  predation on echinoids." Proceedings of the Royal Society B 288.1947 (2021): 20210400. Huang, Yuangeng, et al. "Ecological  dynamics of terrestrial and freshwater ecosystems across three  mid-Phanerozoic mass extinctions from northwest China." Proceedings of the Royal Society B 288.1947 (2021): 20210148.

Podcast 211 - Fossil Ecological Networks

 The gang discusses two papers that look at the ecology of the ancient shark Megalodon. One paper uses our knowledge of modern sharks to fill in the missing data on what Megalodon could have looked like, and the other looks for evidence of Megalodon nurseries in the fossil record. Meanwhile, Amanda cares too much, James spreads “facts”, and Curt would really like to find a segue.   Up-Goer Five (Curt Edition): Our friends talk about two papers that are about a really big angry animal with large teeth that moved through the water and is known by a lot of people. This animal with big teeth lived a long time ago and would have eaten other really big animals. But because most of this animal is made of soft parts, we do not know a lot about what it would have looked like. So the first paper uses other animals which are very close to this big animal (but not as big) and see how they all look to see if bigger things look the same. They find that they can guess what parts of these animals should look like just by looking at their teeth, which is cool! They then use this to guess what this really big old animal could have looked like. The second paper looks at how these big animals would have raised their babies. Some places where we get teeth from these big animals do not have a lot of big teeth, while other places do not have a lot of small teeth. This paper looks at these places to see if the change in how big the teeth are is important. They find that some areas really do have more small than big teeth. Some areas also have more teeth that are between being big or small. It seems that smaller animals (babies) lived in some areas, and then when they get bigger they move out.   References: Herraiz, Jose L., et al. "Use of nursery areas by the extinct megatooth shark Otodus megalodon (Chondrichthyes: Lamniformes)." Biology letters 16.11 (2020): 20200746. Cooper, Jack A., et al. "Body dimensions of the extinct giant shark Otodus megalodon: a 2D reconstruction." Scientific reports 10.1 (2020): 1-9.

Podcast 210 - Mega Shark Doot Do Do Do

 The gang discusses two papers that look at how animals take up space in a community. The first paper looks at ancient reef systems and uses spatial analysis to infer ecological interactions between corals. The second paper looks at the impact that lions have on other predators in South African reserves. Meanwhile, Amanda loves a number, James is an adult, and Curt has some strange ideas about pizza.   Up-Goer Five (Amanda Edition): Today our friends talk about space. Not the cool space, with stars, but the space between animals. The first paper looks at tiny animals that form big groups that look like rocks. There are two kinds of tiny animals that formed big groups that look like rocks from a long time ago. In the first paper, it turns out that some of the tiny animals that formed big groups that look like rocks settle in a space and then make it better for other types of tiny animals that formed big groups that look like rocks. Sometimes we would think that these animals would fight and would not want to help each other, but it turns out that actually they might really need each other to live in a place. This paper uses new ways of doing things, so their stuff is really cool, but is also really new; it's never been done on tiny animals that formed big groups that look like rocks before, only on big tall green trees. So more stuff needs to be done with this new way of doing things. The second paper looks at large animals where boys have lots of hair around their heads and necks and the girls do all the work. The short of it is that when these large animals where boys have lots of hair around their heads are around, there aren't as many smaller things that eat other animals. But there seem to be more kinds of smaller things that eat other animals when large animals where boys have lots of hair around their heads and necks are around. So it is kind of weird.   References: Dhungana, Alavya, and Emily Mitchell. "Facilitating corals in an early Silurian deep-water assemblage." (2020). Curveira-Santos, Gonçalo, et al. "Mesocarnivore community structuring in the presence of Africa's apex predator." Proceedings of the Royal Society B 288.1946 (2021): 20202379.

Podcast 209 - Spacing Out

 The gang discuss two papers that look at community structure in fossil and modern biota. The first paper looks at the size distribution of dinosaur communities and finds an interesting lack of mid-sized predators. The second paper looks at a modern kelp forest community to determine if fishing refugia results in ecological cascades in this system. Meanwhile, James is a magician, Amanda would rather be playing D&D, and Curt remembers Dino Riders.   Up-Goer Five (Curt Edition): Our friends look at two papers that look at how animals live together in a place. The first looks at some very old and angry animals. When people look at how big these old angry animals are, they find something weird. If we look at all the angry things, we have a lot of big things, some small things, but not that much in the middle. When we look at that only eat things that get their food from the sun and see how they are different from the things that eat other animals, they find that this missing middle is because there are no middle animals in the things that eat other animals. One thought for why this could be is that some of the real big animals that eat other animals might have kids that fill the middle when they start to grow up. The second paper looks at these places in the water that you can't drink where there are things that move through the water, things that move on the ground and have big hard things on them that come to points, and things that make food from the sun which are big and green. In a lot of places like this, if there are not some animals that eat a lot, the things with the points can eat all of the big green things. This place doesn't have one of those animals that eats a lot, but it was a place where people can not go in and grab some of the animals that move in the water. Since there are still big green things here, the people who wrote this paper wanted to see if the animals in the water were good at eating the animals with points. It seems that, while the animals in the water are doing better, so are the animals with points. This means that other things must be going on to let the big green things still be there.   References: Malakhoff, Katrina D., and Robert J. Miller. "After 15 years, no evidence for trophic cascades in marine protected areas." Proceedings of the Royal Society B 288.1945 (2021): 20203061. Schroeder, Katlin, S. Kathleen Lyons,  and Felisa A. Smith. "The influence of juvenile dinosaurs on community  structure and diversity." Science 371.6532 (2021): 941-944.

Podcast 208 - Stable States

 The gang discusses two papers that look at snake evolution and ecology. The first paper looks at the evolutionary steps required for venom spitting behavior in cobras, and the second paper looks at how snake populations in the tropics are being impacted by mass amphibian die offs. Meanwhile, James likes the Resident Evil Lady, Curt meets big Bowser, and Amanda has a BIIIIG beer.   Up-Goer Fiver (Curt Edition): Our friends talk about long animals with no legs. Some of these long animals have bad stuff that they can put into your body. The long animals that can make the bad stuff and also make their neck really wide are a group of long animals that have some animals that can push the bad stuff out of their body a great way away from their body. The first paper our friends talk about is trying to find out how these long animals that can push bad stuff a far way out of their body were able to do this. Did they get it from their moms and dads a long long time ago. The paper looks at what the bad stuff is made of, and finds that the things that are close family with the long things that can push bad stuff far away have bad stuff that looks the same. But there is one part of the bad stuff that there is more of in the things that push bad stuff far away that isn't in all of the long animals. The cool thing is, the moms and dads of these animals had this other bad stuff even though they do not push bad stuff far away from their bodies. This means that the other bad stuff changed first, and then the long animals started pushing bad stuff far away from their bodies. The second paper looks at how long animals are hurt when their food goes away. Another group of animals that breathe through their skin has been having a real hard time because they keep getting sick. This paper looks at how the sick animals that breathe through the skin are causing some of the long animals to die because they can no longer get as much food (from the animals that breathe through their skin). Some long animals are doing really well, but most of the long animals are not doing well. This means that something that hurts one group of animals can and will hurt a lot of other animals over time.   References: Zipkin, Elise F., et al. "Tropical snake diversity collapses after widespread amphibian loss." Science 367.6479 (2020): 814-816. Kazandjian, Taline D., et al. "Convergent evolution of pain-inducing defensive venom components in spitting cobras." Science 371.6527 (2021): 386-390. 

Podcast 207 - Sneks and the Toad Wars

 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.

Podcast 206 - In The Face

 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.

Podcast 205 - Horse Couture

 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.

Podcast 204 - Cool Arthropod Bro

 The gang celebrates the end of the year by taking another break to play Fiasco, a crime/noir storytelling game by Bully Pit Games.   Thank you for subscribing to our Mars Inc. weekly newsletter. We value your continued engagement with the Mars Inc. brand. Currently, Mars Inc. is undergoing an aggressive restructuring campaign that will improve efficiency and ensure larger shares for our top job creators. While we are unfortunately still in the planning process, we look forward to sharing our future for the company at our next shareholders meeting next month.   “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/

Podcast 203c - Mars Inc. Part 2

 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. Welcome to Mars Inc., where the future is now!™   “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/

Podcast 203b - Mars Inc. Part 1

 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”.

Podcast 203a - Planning the Fiasco

 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.

Podcast 202 - The Great Plant American Interchange

 The gang discusses two papers are things with legs…. and the word snake is their name. Honestly, we’ve had flimsier excuses for a podcast, jut 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).

Podcast 201 - It's Got Legs!

A group of fresh faced scientists have biweekly informal discussions about evolutionary biology and palaeontology... over beer.

hubhopper

Palaeo After Dark

hubhopper