Palaeo After Dark

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

Podcast 284 - How Complete Is Your Shark 05/19/2024

Podcast 284 - How Complete Is Your Shark The gang discusses two papers that look at the shark fossil record. The first paper looks into the completeness of the record, and the second paper discusses the ecological implications of an exceptionally preserved specimen. Meanwhile, James has ideas of what is normal, Curt has a hard out, and Amanda shows her specific history interests. Up-Goer Five (Curt Edition): The friends talk about two papers that look at animals with lots of soft parts that move through the water and have lots and lots of teeth. The first paper is looking at how well we know these animals in the past, since most of the time we may only know them by their teeth. They do a lot of things to see how much of the animals we have at any time. What they find is that, most of the time, we do not have many parts of these animals. However, there are some times in the past when we do see more parts that are not just teeth, so there might be times in the past that were better and making sure the soft parts were able to stick around and be found later. But most of the time, we really only have teeth or a few other parts, and that this makes these animals different from most other animals that are close to them and that makes sense because the rest of these animals have hard parts where these animals have soft parts. The second paper looks at one of these animals with soft parts where those soft parts were found today. This is the first time this type of animal has been found with its soft parts. Most of the time, we just find the teeth, which look like they were good at breaking hard things. With the soft parts, we can get an idea of how it would move through the water and if it was slow or fast. We can also find out what its brothers and sisters were. What they find is that the soft parts show that this animal looked like a lot of the animals in this group we see today that are not breaking hard things but are catching fast moving food in the water. This is not something we would think would happen, because today animals that have teeth like the ones this animal had don't need to move very fast to catch their food. This shows that this animal was doing something that we don't see today. This might be because there were lots of animals with hard parts on the outside that were moving in the water really fast at that time, which this one animal would have tried to catch for food. References: Schnetz, Lisa, et al. "The skeletal completeness of the Palaeozoic chondrichthyan fossil record." Royal Society Open Science 11.1 (2024): 231451. Vullo, Romain, et al. "Exceptionally preserved shark fossils from Mexico elucidate the long-standing enigma of the Cretaceous elasmobranch Ptychodus." Proceedings of the Royal Society B 291.2021 (2024): 20240262. /episode/index/show/palaeoafterdark/id/31273912

Podcast 283 - Stolen Podcast 05/05/2024

Podcast 283 - Stolen Podcast The gang discusses two papers about an interesting locality in South America and the various body fossils and ichnofossils found in this locality. This podcast originally started as a patreon request to podcast about fossil procyonids… but it ended up like this… ooops! Meanwhile, James has a vocal doppelganger, Amanda deals with being human, Curt deals with scams, and everyone talks way too much about visuals on an audio podcast. Up-Goer Five: (Curt Edition) The friends talk about a place that has rocks from a long time ago that give us an idea of the types of animals that were around in the land areas under where the friends are today. The land where our friends are one used to not be touching the land that is under them like it is now. Once these two lands touched, then the animals from each land moved into the other lands. This place is from a time before these two lands had finished touching, so some animals moved over but others had not yet. The first paper looks at some parts of a type of animals that is brother/sister to animals that grab food out of our place we put food that we can not eat anymore. These animals had moved onto the land under the land our friends are on before the two lands had stopped touching. The place where these parts are found is interesting because it seems like it is under water for some time but there are some bits that are not under water. The first paper shows some marks in the ground that are interesting, but the second paper goes in on these marks to show that they are homes and marks from food searches from other animals. These marks show that the animals in this area were doing a lot of things to make homes and look for food under the ground. This shows that even before other animals moved from the other land, animals in this area were doing cool things in the ground. References: Soibelzon, Leopoldo H., et al. "First record of fossil procyonid (Mammalia, Carnivora) from Uruguay." Journal of South American Earth Sciences 92 (2019): 368-373. Varela, Luciano, et al. "Late Miocene mammalian burrows in the Camacho Formation of Uruguay reveal a complex community of ecosystem engineers." Evolving Earth 1 (2023): 100023. /episode/index/show/palaeoafterdark/id/31127078

Podcast 282 - Early Fishies 04/21/2024

Podcast 281 - Climate and Extinction 04/07/2024

Podcast 281 - Climate and Extinction The gang discusses two papers that look at the correlation between climate change and extinction risk in the fossil record. The first paper uses climate modeling to simulate extinction risk during past periods of climate change, and the second paper uses new radiometric age dates to infer diachronous extinction between marine and terrestrial environments during the Permian mass extinction. Meanwhile, James orders food, Curt stirs the pot, and Amanda lives with her choices. Up-Goer Five (Curt Edition): The friends look at two papers that look at times when a lot of things died. The first paper uses computers and numbers to see how things could die during times when things get real hot or real cold. They look at real times in the past when lots of things die during these cold and hot times, and then they use their computers and numbers to make those things happen in the world of a computer to see if they can find out what may or may not make that happen. They find that lots of things can cause animals to die during these times when things get hot or cold, but how big the space animals live in and how many different types of places these animals can live in are big for knowing if they will or will not die. The second paper looks at a time in the past when almost everything died. This is a time when it got real hot. Things die on the land and in the water. A lot of what we study is in the water because those things are able to get covered in ground faster than the things that live on the land. But this paper finds some rocks from the land and does some work with the matter that makes up these rocks to see how old the rocks are. These rocks have animals in them that would die because of this big bad time when everything died. But the time that they found was after when everything in the water died. So this could mean that animals may have died first in the water and then died after on the land. This could be because the way the world changes when things get hot is going to be different in the water and on land. References: Malanoski, Cooper M., et al. "Climate change is an important predictor of extinction risk on macroevolutionary timescales." Science 383.6687 (2024): 1130-1134. Wu, Qiong, et al. "The terrestrial end-Permian mass extinction in the paleotropics postdates the marine extinction." Science Advances 10.5 (2024): eadi7284. /episode/index/show/palaeoafterdark/id/30710663

Podcast 280 - Just a Weird Little Guy 03/24/2024

Podcast 279 - Frogcast 03/10/2024

Podcast 279 - Frogcast The gang discusses two papers that look at the fossil frog record. The first paper identifies fossil frogs from Antarctica, and the second paper looks at some exceptional soft-tissue preservation. Meanwhile, James has ideas for expanding the brand, Amanda asks for clarification on an important topic, and Curt makes some executive decisions. Up-Goer Five (James Edition): The group looks at two papers that are interested in animals that are wrong and good at jumping and live in the water but some can walk on land and climb trees. The first paper is looking at one from the very cold land in the bottom of the round thing we live on, where we do not find any of them today because it is too cold. The animal is known by two small bits but we can tell what type of jumping thing it is and so we know it is part of a group that is found in two areas that do not touch today, but the place at the bottom of the round thing we live on is between them, so that makes sense! But it is very cold today, so that is strange, but the animal being there and the things we find with it seems to show that is must have been a little hotter then. The second paper is looking at one of the animals that is good at jumping that is found with lots of round things that become babies in it. This is very cool because the animal is also still soft in places in it that means it was not the most grown it could be and so was making babies when it was still young. There is also a thought that the animal may have died while trying to make babies which is interesting. References: Mörs, Thomas, Marcelo Reguero, and Davit Vasilyan. "First fossil frog from Antarctica: implications for Eocene high latitude climate conditions and Gondwanan cosmopolitanism of Australobatrachia." Scientific Reports 10.1 (2020): 5051. Du, Baoxia, et al. "A cretaceous frog with eggs from northwestern China provides fossil evidence for sexual maturity preceding skeletal maturity in anurans." Proceedings of the Royal Society B 291.2016 (2024): 20232320. /episode/index/show/palaeoafterdark/id/30302008

Podcast 278 - The Wrong Shapes 02/25/2024

Podcast 277 - Bird Tracks For Fun and Profit 02/11/2024

Podcast 277 - Bird Tracks For Fun and Profit The gang discusses two papers that look at Mesozoic tracks that may or may not have been made by an avian archosaur. Meanwhile, Curt becomes activated, Amanda has to deal with harsh truths, James gets creative with taxon names, and everyone get distracted very quickly. (Editor’s Note: If you want to just “get to the science” skip to 11 minutes in. We hadn’t talked in 2 months and it shows. I just didn’t have the heart to cut all of it) Up-Goer Five (Curt Edition): The friends look at two papers that look at foot falls in the ground from a very very long time ago which may or may not be made by animals that can fly through the sky, or may have been made by big angry animals. The problem is that big angry animals and the animals that can fly are very close to each other, and their foot falls can look a lot like each other. The first paper looks at some very old foot falls and some of these foot falls do look like they were made by animals that can fly, but that would be very very strange because it would need a lot of other things to be true if that were true. They say that there was something moving like these animals today that can fly but were probably not those types of animals, but it shows how hard it can be to see if these foot falls were made by these animals that can fly. The second paper uses numbers to try and see if we can really see if some of these foot falls were made by animals that fly. What they find is that we have used how big these foot falls are as a reason why we think some are from big angry animals and some are from animals that can fly. This is maybe a problem because we know there are small big angry animals, and that today there are some big animals that are from the group that can fly. If you use numbers to take how big they are out of the running, it seem like some of these foot falls could be from big animals part of the group that can fly. References: Abrahams, Miengah, and Emese M. Bordy. "The oldest fossil bird-like footprints from the upper Triassic of southern Africa." Plos one 18.11 (2023): e0293021. Hong, Sung-Yoon, et al. "The discovery of Wupus agilis in South Korea and a new quantitative analysis of intermediate ichnospecies between non-avian theropods and birds." Cretaceous Research 155 (2024): 105785. /episode/index/show/palaeoafterdark/id/29886513

Podcast 276c - In the Woods Somewhere Part 3 01/28/2024

Podcast 276b - In the Woods Somewhere Part 2 01/14/2024

Podcast 276a - In the Woods Somewhere Part 1 12/31/2023

Podcast 275 - Big N Wormy 12/17/2023

Podcast 274 - Cause and Effect and Cause 12/03/2023

Podcast 274 - Cause and Effect and Cause The gang discusses two papers about taphonomy and its influence on our understanding of the fossil record. The first paper looks at how taphonomic processes can blur our understanding of cause and effect, while the second paper looks at the impacts of collector and size biases on our understanding of the ecology of an ancient plant. Meanwhile, James deals with spirits, Curt gets philosophical, and Amanda smartly ignores things. Up-Goer Five (Curt): The friends talk about two papers that look at the ways in which the things we know can be changed because of other problems that we do not always know are there to make things look like one thing but actually be another thing. The first paper looks at how not getting things to be saved over time could mean that you might not see the reason something happens until it looks like it is after that thing has happened. The paper uses a time in the past when it got very cold and looks at what could have made this happen. There are lots of talk about the growing of big things that make their own food from the sun on land, but this paper shows that what we can see might not be the real time when big things started really doing well. While it sounds strange, it might be best to look at something that we see in the rocks after the time that it gets cold, since the thing that changed probably changed before we can see it in the rocks. The second paper looks at another thing that makes its own food from the sun. This old thing could have lived in a lot of different ways and there are lots of people who think one way or another. Some think these things need to burn as part of their life, and some people think that these things would live near water and might get burned only sometimes. The people who wrote this paper looked at how people found these things, if they picked up ones that were big or small, and also went out to find more of these things. What they find is that some of the reasons people have not known how these things lived is because we grab big parts to save but most of the things are found as small parts that have burned. This means that it seems that burning was an important part of the lives of these things. References: Blanco‐Moreno, Candela, Hugo Martín‐Abad, and Ángela D. Buscalioni. "Quantitative plant taphonomy: the cosmopolitan Mesozoic fern Weichselia reticulata as a case study." Palaeontology 65.6 (2022): e12627. D'Antonio, Michael P., Daniel E. Ibarra, and C. Kevin Boyce. "The preservation of cause and effect in the rock record." Paleobiology 49.2 (2023): 204-214. /episode/index/show/palaeoafterdark/id/28893463

Podcast 273 - The Hunt for Red Plankton 11/19/2023

Podcast 273 - The Hunt for Red Plankton The gang discusses two papers that look at plankton through time. The first paper looks at some Cambrian acritarch fossils and shows that they are likely colonial algae, and the second paper looks at how shifting temperature affected plankton distribution across the Cenozoic. Meanwhile, everyone stays completely on task with the stated goals of this podcast: a detailed (and wrong) discussion on the events of the movie “The Hunt for Red October”. Yes, it is going to be “one of those” podcasts. Up-Goer Five (Curt Edition): The friends talk about two papers that look at things that live in the water without having to move parts to stay in the water and maybe they are single cells and maybe they are groups of cells. The first paper looks very very old things that live in the water. These old things are so old and hard to figure out that people are not always sure what they are. These things are often thought to be all single cells. This paper shows that some of these things that are very old might be groups of cells that are living together. The way that these cells group together does look like some things that live in the water today that make food from the sun. This paper shows that this type of cell or something like it might have been around a very very long time ago. The second paper looks at how where things living in the water but not moving and maybe they are single cells and maybe they are groups of cells, could have lived when things got cold in the past. They see that there are changes in the types of these things over time and where the live. They show that the way things are today is because it was getting colder. It also shows that, when things warm up, we might see some big changes in where these things are. References: Woodhouse, Adam, et al. "Late Cenozoic cooling restructured global marine plankton communities." Nature 614.7949 (2023): 713-718. Harvey, Thomas HP. "Colonial green algae in the Cambrian plankton." Proceedings of the Royal Society B 290.2009 (2023): 20231882. /episode/index/show/palaeoafterdark/id/28702328

Podcast 272 - The Tardigrade Cast 11/05/2023

Podcast 271 - Feel It In My Guts 10/22/2023

Podcast 271 - Feel It In My Guts The gang discusses two papers that look at the gut contents and traces of ancient animals. The first paper reconstructs gut traces (or lack thereof) for Ediacarans and then the second paper looks at the detailed gut contents and 3d track of a lichid trilobite. Meanwhile, Amanda’s cat is changing careers, James is feeling “motivated”, and Curt has some house improvement recommendations. Up-Goer Five (Curt Edition): The friends talk about the insides of different animals from a long long time ago. The first paper looks at animals from a long long time ago that do not look much like things we see today. There is a lot of talk about how these animal would eat and where the food would go when they did eat. This paper looks at the parts that remain and looks over the things that are left behind to see if they can find out what the insides of these things were like. What they find is that the things we think are more like things we see today all have insides where the food goes. The one really strange thing does not and could have had food move into it along its outside. The second paper looks at a small animal with many parts that makes a hard home. This paper finds the food that it ate in its insides and can use it to see what the insides look like. This is a great way for us to see the insides where the food goes in a group that is not around anymore. Also, the food in the insides lets us know how this animal ate things and the way it ate is strange when we look at things today. This thing ate hard things but it did it in a way that is not like what we see today. Also, this animal may have been getting ready to grow but did not make it. References: Kraft, Petr, et al. "Uniquely preserved gut contents illuminate trilobite palaeophysiology." Nature (2023): 1-7. Bobrovskiy, Ilya, et al. "Guts, gut contents, and feeding strategies of Ediacaran animals." Current Biology 32.24 (2022): 5382-5389. /episode/index/show/palaeoafterdark/id/28381247

Podcast 270 - Rafting Away 10/08/2023

Podcast 269 - Baba Yaga's Whale Facts As Written By ChatGPT 09/24/2023

Podcast 268 - Tooth Hurts 09/10/2023

Podcast 267 - The Blender Episode 08/27/2023

Podcast 266 - Tooth and Jaw 08/13/2023

Podcast 266 - Tooth and Jaw The gang discusses two papers that looks at mammal jaws and teeth. The first paper uses many different analyses to study how the mammal jaw evolved, and the second paper looks at a unique set of teeth in a fossil whale group. Meanwhile, Curt gets ideas from Mortal Kombat, James has discusses farming practices, and Amanda finds any excuse to be fabulous. Up-Goer Five (Curt Edition): The friends talk about two papers that look at how mouths for animals with hair have changed over time. The first paper looks at the bottom hard part of the mouth to see how it first started and how it has changed and why it changed. Lots of people have ideas about this, but this paper is the first attempt to really look at this problem for a lot of different ways of handling it. They do a lot of things that are very number heavy to look at how these hard parts are able to move, and they look at a lot of parts from living and long dead things. What they find is that the bottom mouth parts of animals with hair are not as good as we thought. They are hard so they do not break, but other animals have bottom mouth parts that are easier to use and quicker. Because animals with hair make their bottom mouth from just one hard part, it may have made it easier for them to get many different teeth in the mouth. This is a story that has a lot more parts than just, "animals with hair had better everything so that is why there are now a lot of them" and instead shows that some changes were not "better" but may have opened doors to other ways to use a mouth (like many different teeth in the same mouth). The second paper looks at one animal with hair that moves through the water and has some very weird teeth that push out the front of the mouth. But first, the paper needs to see if these are really teeth. Some long teeth like things are found in other animals with hair, but these long things do not have all the parts to be teeth. When they look at this animal, they see that these are actually really long teeth. This is interesting because teeth can be more hurt by things than the long teeth like things. So if these are teeth, what did they do with them? They do not have breaks and they would not be good for moving through the ground looking for food, so the people who wrote the paper think they might be used to cut food. References: Tseng, Z. Jack, et al. "A switch in jaw form–function coupling during the evolution of mammals." Philosophical Transactions of the Royal Society B 378.1880 (2023): 20220091. Coste, Ambre, R. Ewan Fordyce, and Carolina Loch. "A new dolphin with tusk-like teeth from the late Oligocene of New Zealand indicates evolution of novel feeding strategies." Proceedings of the Royal Society B 290.2000 (2023): 20230873. /episode/index/show/palaeoafterdark/id/27685335

Podcast 265 - Big Boy Season 07/30/2023

Podcast 264 - Old Elvis Taxon 07/16/2023

Podcast 264 - Old Elvis Taxon The gang discusses two papers that look at the ecomorphology of Mesozoic swimming reptiles. The first paper investigates swimming strategies in various marine swimming reptile groups, and the second paper looks at changes in the skull of mosasaurs compared to stem whales. Meanwhile, James has a meal, Amanda “makes” animals, and Curt needs more insight. Up-Goer Five (Curt Edition): The friends look at two papers that look at how big angry animals that move through the water lived a long time ago. The first paper looks at how these big animals moved through the water, because there are many ways that an animal can move through water. They use numbers to look at how these animals look, and they also use some animals from today that move through water to see if the way they look is like the ones from the past. They find that there are some ways that animals look with their bodies that change how they move through the water. This shows a lot of cool things. Some groups start moving through water in one way and over time move to a different way. This shows that there was a lot of different ways these groups of big angry animals were able to move through the water. The second paper looks at the heads of one group of big angry animals from the past that move through water and also an old group of big animals with hair that move through water that are still around today. The paper wants to see if both of these groups do the same things with their heads since they are both moving into moving through water. They find that a few of the heads kind of look like each other between these two groups, which could be that they were trying to eat the same things. However, most of the time these two groups are not looking the same in the head. This is because these two groups come from different things and so they are not able to change their head in the same way. References: Gutarra, Susana, et al. "The locomotor ecomorphology of Mesozoic marine reptiles." Palaeontology 66.2 (2023): e12645. Bennion, Rebecca F., et al. "Convergence and constraint in the cranial evolution of mosasaurid reptiles and early cetaceans." Paleobiology 49.2 (2023): 215-231. /episode/index/show/palaeoafterdark/id/27466254

Podcast 263 - In the Presence of ALAN 07/02/2023

Podcast 263 - In the Presence of ALAN The gang discusses two papers that look at the impact of humans on bird populations. The first paper looks at the history of a condor nesting site in the Andes, and the second paper looks at the impact of artificial light on the circadian rhythms of urban bird populations. Meanwhile, James is highly engaged, Curt tries to sell some property, Amanda finds something slightly more horrifying, and everyone is in the presence of ALAN. Up-Goer Five (Curt Edition): The friends look at how people have made life different for small animals that fly in the air and some of them make sweet sounds. The first paper looks at the home for one type of these animals that is pretty big and eats things that are dead. These animals have been using this home for a really long time, and we can look at their shit (yes this is the only word I can use) to see what they ate in the past and also see how long they have been there. A long time ago, their shit shows that they ate a lot of things from the big blue wet thing, probably lots of big animals that have hair and move through the water. When people started to kill these big animals, these animals that fly started to eat less of them. We can even see when these animals started to eat things that people from across a different big blue wet thing brought with them to eat. This shows that these homes are used for very long time, and so making sure that these animals can get to these homes and that the homes are safe is important to keeping them living. The second paper looks at how some small animals that fly sleep and if being in a city makes these animals sleep at different times or for longer or shorter. The idea is that the city has a lot more light than the woods and can make it harder to get to sleep. The paper looks at these animals living in the woods and animals living in the city. It first looks at their homes to see how much time they spend in their homes. They find that both groups of animals spend about the same time in their homes. City animals get out of their homes earlier in the day, but that seems to be that they are also setting up their home earlier in the year and need to get out to get stuff for the home. They then take these animals and they put them in a dark room to see how much they move with no change in light. They find the woods animals start moving less right away, but the city animals take longer before they start moving less. This could be because the room has low light and the animals from the city are more used to that, or it could be that the animals from the city are more used to being in bad spots. Either way, it shows that these animals are showing changes to work around the light from the city. References: Duda, Matthew P., et al. "A 2200-year record of Andean Condor diet and nest site usage reflects natural and anthropogenic stressors." Proceedings of the Royal Society B 290.1998 (2023): 20230106. Tomotani, Barbara M., Fabian Timpen, and Kamiel Spoelstra. "Ingrained city rhythms: flexible activity timing but more persistent circadian pace in urban birds." Proceedings of the Royal Society B 290.1999 (2023): 20222605. /episode/index/show/palaeoafterdark/id/27279225

Podcast 262 - Take It To The Mat 06/18/2023

Podcast 262 - Take It To The Mat The gang discusses two papers that study the paleoecology of the Ediacaran fauna. The first paper looks at environmental information that can be gleaned from the microbial mats these organisms lived on, and the second paper studies how different Ediacaran fossils are distributed on this microbial mat. Meanwhile, James is having a week, Curt is unsure about chips, and Amanda is comfortable being very on brand. Up-Goer Five (Curt Edition): The friends look at two papers that study some very old animals that lived a long long time ago and lived on these beds of tiny tiny tiny animals and not animals. In fact, these two papers are also interested in the beds these things lived on and how they lived on the bed. The first paper looks at these parts of the beds and how you can find them in different beds made of tiny tiny tiny animals and not animals. There are these lines in the beds that are found in some beds but not all of the beds. They think that the way water moves over the beds may cause these lines to form. The other cool thing they find is that the animals are found when there are these lines, and are not found when there are not these lines. This means that the way the water moves might be important for these animals to live. The second paper looks at how these animals lived in space with each other. Did they want to live close to each other or did they want to be far from each other, or do they not really care? Some earlier papers had said they wanted to be far from each other, which is weird when we look at animals in the big blue wet thing today which want to stay close to each other. So they run a lot of studies on three different animals that can show if they are close to each other because they all need the same thing (and that thing is in small parts around the ground) or if they seem to want to be very close to each other because they either use each other or they can not move far from each other. They show that these animals all show that they are close to each other, but two of the animals are close because they all want something that is in just a few places. One animal shows a really strong need to be close, which could mean that this is something about the animal that makes new babies be closer to the father/mother. This shows we can learn things about how these animals lived and why they lived where they did, even for things that are very very very old. References: Boan, Phillip C., et al. "Spatial distributions of Tribrachidium, Rugoconites, and Obamus from the Ediacara Member (Rawnsley Quartzite), South Australia." Paleobiology (2023): 1-20. Tarhan, Lidya G., Mary L. Droser, and James G. Gehling. "Picking out the warp and weft of the Ediacaran seafloor: Paleoenvironment and paleoecology of an Ediacara textured organic surface." Precambrian Research 369 (2022): 106539. /episode/index/show/palaeoafterdark/id/27084558

Podcast 261 - Bad Coping Strategies 06/04/2023

Podcast 261 - Bad Coping Strategies The gang discusses two papers about inferring life habit and ecology from extinct animals. The first paper summarizes the data for ichthyosaur birth to see if they really do preferentially come out tail first, and the second paper investigates a fossil that could complicate the narrative for the origins of a European sabretooth cat group. Meanwhile, James has opinions about browsers, Amanda is camouflaged, Curt needs a drink, and everyone is surprised by a paper for the first time in a long time. Up-Goer Five (Curt Edition): The friends talk about two papers that looks at how animals did things and where they lived in the past. The first paper looks at a group of animals that lived in the water and had their kids inside them. This group used to be on land before they went into the water for all time. Lots of people say that when a group of animals goes from being on land to being on water, they need to change the way the babies come out of them, with the head coming out last so that they do not breathe in water. This paper looks into this to see if this is true. It turns out that lots of things today that used to be on land but are now in the water and have kids inside them usually have the kids come out with the head last. However, this is not always what happens. And, when the kids come out head first it is fine and they do not die and the mom also does not die. When we look at the parts of the dead animals from a long time ago that live in the water, we also see that, even in the groups that everyone says they go out head second, there are some that show they come out head first. It seems like, instead of being a change that is always true, these animals went from being most of the time head first, to being half and half head first, to being most of the time head second but sometimes head first. The second paper looks at a group of angry animals with hair and long teeth. This group is found all over the world in the past and this paper is looking at one group that is most of the time found in one place but may have also had some groups close to it from other places. This paper names a new type of these animals and says that it is the first of this group, but also the study they do says that it isn't so that is weird. They also do another study to show that this group went through most of its big changes in this new place, but the study they do also seems to say that it is a third different place where a lot of important things happen but they do not talk about it. This paper is weird. References: Jiangzuo, Qigao, et al. "Origin of adaptations to open environments and social behaviour in sabretoothed cats from the northeastern border of the Tibetan Plateau." Proceedings of the Royal Society B 290.1997 (2023): 20230019. Miedema, Feiko, et al. "Heads or tails first? Evolution of fetal orientation in ichthyosaurs, with a scrutiny of the prevailing hypothesis." BMC Ecology and Evolution 23.1 (2023): 1-13. /episode/index/show/palaeoafterdark/id/27035067

Podcast 260 - Making Due With What You Have 05/21/2023

Podcast 260 - Making Due With What You Have The gang discusses two functional morphology papers. The first paper looks at eye placement and skull morphology in Thylacosmilus and the second paper looks at the ungals of maniraptoran theropods. Meanwhile, James has milk filled “vegan” food, Amanda is replaced by alternate universe goatee Amanda, and Curt looks to rebrand. Up-Goer Five (Curt Edition): The friends talk about two papers that look at animals who have very strange parts and how they may or may not have used those parts. The first paper looks at a group of animals with long teeth that eats other animals but is not close to the animal group with long teeth that we all know. This group got long teeth on their own and through a different way. This paper looks at their heads and shows that the way they got long teeth changes how their eyes are put into the head. Most animals that eat other animals have eyes that face forward, this helps them see how close things are in front of them. The long teeth of this animal pushed the eyes to the side, which makes it look very different from other animals that eat animals. The paper shows that there are other changes in the head that make it so the eyes can focus better even though they are not in the "right" place. This shows that there are other ways for animals to get good sight to eat other animals even if their eyes are not facing forward. The second paper looks at the hands of a group of big angry animals from a long time ago. One part of this group gets really long fingers, and another part of this group get very short fingers (some only a few fingers). This paper looks at many ways to see how these animals could have used their really long or really short fingers. What they find is that the fingers get more strange as the groups go on. Earlier animals from these groups seem to be able to use their fingers for lots of things, but as the animals get more strange fingers they seem to only be used for a few things. The short fingers might be used to move ground out of the way. The long fingers are so strange that we are not sure what they were used for. References: Qin, Zichuan, et al. "Functional space analyses reveal the function and evolution of the most bizarre theropod manual unguals." Communications Biology 6.1 (2023): 181. Gaillard, Charlène, Ross DE MacPhee, and Analía M. Forasiepi. "Seeing through the eyes of the sabertooth Thylacosmilus atrox (Metatheria, Sparassodonta)." Communications Biology 6.1 (2023): 257. /episode/index/show/palaeoafterdark/id/26890185

Podcast 259 - Niche Evolution or Conservatism 05/07/2023

Podcast 259 - Niche Evolution or Conservatism The gang discusses two papers that look at patterns of niche conservatism or niche evolution in the fossil record. The first paper looks at the pollen records of trees in Portugal to test if changing climate can explain modern tree distributions, and the second paper looks at the impact of Late Devonian extinction pulses/invasions on brachiopod communities. Meanwhile, Curt summarizes the podcast, James has brachiopod facts, and Amanda cannot control her cats. Up-Goer Five (Curt Edition): Our friends talk about two papers that look at where animals live and what they do in the world, and also if that stays the same or changes over time. The first paper looks at tall living things that make their own food and lose a part of themselves every fall. This looks at one place that has just a few of these types of living things but in the past there were different types there. Also, back then it was not as warm and the rain was different. This paper wants to see why the tall living things we have in this part of the world are where they are right now. What they saw was that, some of the changes in the tall things seem to be tall things following where they want to live; when things get warmer or colder they move to follow the change. But some things seem to be moving into places that are very different from where they started, so they are changing what types of places they like to live in. The second paper looks at animals that live on the bottom of the big blue wet thing and take food out of the water and were found all over the world a long time ago. It looks at a time when a big change killed a lot of living things. This paper looks at how this changed the types of these animals over time. What they find is that, a lot of the animals that die because of the change have another animal from somewhere else doing the same thing move in and take that animal's place. The things that do not die just keep on doing their own thing. It does not look like there is much change in what the animals are doing either from the big change that happened, or from the new animals moving in. References: Vieira, Manuel, et al. "Niche evolution versus niche conservatism and habitat loss determine persistence and extirpation in late Neogene European Fagaceae." Quaternary Science Reviews 300 (2023): 107896. Brisson, Sarah K., et al. "Niche conservatism and ecological change during the Late Devonian mass extinction." Proceedings of the Royal Society B 290.1996 (2023): 20222524. /episode/index/show/palaeoafterdark/id/26763618

Podcast 258 - Problematica or Not? 04/23/2023

Podcast 258 - Problematica or Not? The gang discusses two papers that look at some Cambrian problematic fossils and find new clues that allow us to determine what groups they might belong to. One paper finds new evidence that some of these tube fossils in the Cambrian may be cnidarians and the other paper identifies potential gastropod radula in Cambrian rocks with adaptations for grazing. Meanwhile, James is not at all tired, Amanda will totally clean out her garage, and Curt is in the loop about what is going on. Up-Goer Five (Curt Edition): The friends talk about two papers that look at some things from a long time ago that are very hard to see what is going on with them but these new finds give us a better idea of what they might be. The first paper looks at these long and soft things. We used to think they were long and soft things that live in the ground today. However, this paper finds that there are little arms on one side and that they have these parts that we see in a very different group of animals that instead has one way in that it uses to eat and shit and has lots of these small arms. They show this for one of these types of animals but it could be that a lot of the long soft animals we find that we are not sure about could all be parts of this group. The second paper looks at these small bits that people find when they take rocks and break them down into bits. These small things look like the mouth parts of animals that are soft and some of them carry their home with them. Not just mouth parts, but mouth parts that can eat green things that make their own food. This could be the first time we see animals that just eat these kinds of green things in the past. References: Zhang, Guangxu, et al. "Exceptional soft tissue preservation reveals a cnidarian affinity for a Cambrian phosphatic tubicolous enigma." Proceedings of the Royal Society B 289.1986 (2022): 20221623. Slater, Ben J. "Cambrian ‘sap-sucking’molluscan radulae among small carbonaceous fossils (SCFs)." Proceedings of the Royal Society B 290.1995 (2023): 20230257. /episode/index/show/palaeoafterdark/id/26621148

Podcast 257 - Slow Fliers 04/09/2023

Palaeo After Dark

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