Palaeo After Dark

The gang discusses two papers that look at the evolutionary changes occurring in early synapsids. The first paper suggests that some synapsids may have evolved a mammal-like walking gate and respiration earlier than we expected, and the other paper uses the inner ear of synapsids to infer body temperature. Meanwhile, James is adapting to a new environment, Amanda drinks some "tea", and Curt gives acronym advice.

Up-Goer Five (Curt Edition):

Our friends talk about two papers that look at animals which are not the animals today with hair and warm blood but are part of the group that is brother and sister to those animals. These animals were around a long long time ago. These papers show that some of the things we see in animals with hair and warm blood today also happened in some of these other animals too. The first paper looks at a hard part inside the chest of these other animals. Most of these other animals have a hard part that is very different from the one we see in the animals with hair and warm blood. However, on group of these other animals seems to have a hard part that looks a lot like the ones we see today in animals with hair. This hard part is important for how we breathe and also how we move. This means that this group may have walked and breathed like the animals who have hair today, even though animals with hair got this hard part much later.

The second paper looks at the ear to see how warm the blood is for these other animals that are not animals with hair but are part of the group. This paper uses the water stuff in the ear to try and figure out how warm these animals would be. They look at the ear for a lot of dead animals from this group, as well as animals around today that we can see how warm they are. When they use what they find today on the very old dead animals, they see that there is a point in the past of these animals where they start to really get warm. This is still earlier in the group than our animals we have around today with hair that are warm.

References:

Bendel, Eva-Maria, et al. "The earliest segmental sternum in a Permian synapsid and its implications for the evolution of mammalian locomotion and ventilation." Scientific Reports 12.1 (2022): 1-9.

Araújo, Ricardo, et al. "Inner ear biomechanics reveals a Late Triassic origin for mammalian endothermy." Nature (2022): 1-6.

The gang discusses two papers that look at the ecological impacts of major extinction events. The first paper looks at the ecological stability of marine communities before and after two mass extinction events, the late Ordovician and the end Permian. The second paper simulates an extinction event on modern bird populations to determine if this would most strongly impact functional diversity or phylogenetic diversity. Meanwhile, Amanda learns about something new to worry about, James shares dubious life advice, and Curt questions movie curses.

Up-Goer Five (Amanda Edition):

Today our friends look at two papers about things dying. The first paper wants to know if having more things that do all the same stuff will help keep the world better when everything else is dying. They look at an early time and then a later time that everyone knows is very, very, very bad. The earlier time is thought to be the second-most bad time for taking out things that do different things. But the paper shows that since, in that earlier time, there are more things doing the same thing, it's actually not so bad as the later time, when there are not so many things doing the same thing. More things are doing different things, so that the dying is worse.

The second paper is looking at animals that fly and don't have hair or hard skin. This paper is saying that some animals that fly and don't have hair or hard skin are dying more. However, these animals are not like brothers and sisters to each other, instead, they look like each other. This paper finds that animals that fly that do not have hair or hard skins that live in some places will start to look like each other more and more because some of the animals die out. That means that the remaining animals that fly but do not have hair or hard skin will be more like each other, and it means that things in these places might get bad, because there will be only a few things left that do one or two things.

References:

Dick, Daniel G., et al. "Does functional redundancy determine the ecological severity of a mass extinction event?." Proceedings of the Royal Society B 289.1979 (2022): 20220440.

Hughes, Emma C., David P. Edwards, and Gavin H. Thomas. "The homogenization of avian morphological and phylogenetic diversity under the global extinction crisis." Current Biology (2022).

The gang discusses two papers that analyze exceptional fossils using CT scanning. The first paper looks at an exceptionally preserved vampire squid, and the second paper looks at an exceptionally preserved early mammal. Meanwhile, Amanda follows medical advice, James is a consummate professional, and Curt learns about coleoids in real-time.

Up-Goer Five (Curt Edition):

Our friends look at two papers that use an important way of looking at things through hard stuff to try and figure out what a lot of older animals actually looked like. The first paper looks at an animal with an arm, and an arm, and an arm, and an arm, and an arm, and an arm, and an arm, and an arm which looks like it could hurt you but really just spends its time eating dead things. There is only one of these animals around today, but this older animal is thought to be a part of this group. By using this way of looking through hard parts, we can say that this old animal is a part of this group. Also, we can see that there are some ways that it is not the same as the living one. It seems that the old animal may have eaten things that were living, which is very different from how the animal around today lives.

The second paper looks at an old animal from a group we are a part of that has hair and warm blood. As we have talked about before, figuring out when we have the first of this group of animals is very hard, and lots of changes happen early on that then go back again. This animal gives us some really cool ways to look at some of these changes early on in this group. By using this way of looking through hard parts, they can look inside the head and see the ear parts. Ear parts are an important part of being a part of this group. So seeing how the ear parts have changed is a good way to see how this group is changing over time.

References:

Wang, Hai-Bing, et al. "A new mammal from the Lower Cretaceous Jehol Biota and implications for eutherian evolution." Philosophical Transactions of the Royal Society B 377.1847 (2022): 20210042.

Rowe, Alison J., et al. "Exceptional soft-tissue preservation of Jurassic Vampyronassa rhodanica provides new insights on the evolution and palaeoecology of vampyroteuthids." Scientific reports 12.1 (2022): 1-9.

The gang discusses two papers that look at what past sharks might have eaten. The first paper uses nitrogen isotopes to determine the trophic level of species belonging to the extinct shark genus Otodus, and the second paper shows evidence of predation/scavenging of sperm whales by sharks in the late Miocene. Meanwhile, James has a couch to burn, Curt proposes an experiment to find the best animal, Amanda becomes shark Nietzsche.

Up-Goer Five (Curt Edition):

Our friends look at two papers that look at what big angry animals with big teeth who breathe water and lived in the past could have eaten. The first paper looks at the parts of these animals from the past and uses what those parts of made of to try and see what kind of things they might have eaten. This is the first time that this has been done using these parts of the animal, since most of these kinds of papers look at living animals and so they can get parts that do not last when the animals die. It had been said that these big angry animals in the past may have eaten big animals that eat small things, and that they might have died out when there was less big animals that eat small things. This paper finds that the parts that make up these animals show that maybe these animals were eating things that ate other bigger things, that these big animals were probably not just eating this one type of animal but may have gone for anything, as well as other animals that also eat pretty much everything. One animal that they mention these big angry animals that breathe water could have eaten is a big animal with warm blood and big teeth that lives in water.

The second paper looks at how the hard parts of big animals with warm blood and big teeth that live in water at this time have hurt marks on their hard parts that look like they were from the teeth of big angry animals that breathe water. These hurt marks are along a part of the head that has a lot of stuff in it which animals would like to eat. The hurt marks are all different, with some that look like the animal bit them right on the head, and others look like marks from teeth that were biting at the body when it was already dead. It seems like many different types of angry animals with big teeth who breathe water may have been eating these animals with warm blood and big teeth.

References:

Kast, Emma R., et al. "Cenozoic megatooth sharks occupied extremely high trophic positions." Science Advances 8.25 (2022): eabl6529.

Benites-Palomino, Aldo, et al. "Sperm whales (Physeteroidea) from the Pisco Formation, Peru, and their trophic role as fat sources for late Miocene sharks." Proceedings of the Royal Society B 289.1977 (2022): 20220774

The gang discusses two papers that look at the impact of the end Cretaceous mass extinction. The first paper looks at ecomorphospace changes in mosasaur communities prior to the extinction event, and the second paper discusses the importance of a large freshwater gar which lived through the recovery. Meanwhile, James has some new and interesting ecological theories, Curt is simpatico with his recording equipment, and Amanda acts as our resident "fish" expert. Up-Goer Five (Curt Edition): Our friends talk about two papers that look at a time when a big rock hit us a long long time ago. The first paper looks at how big angry animals in the water that you can not drink did before the big rock hit. There is a big question about if these big angry animals that live in water you can not drink were doing well before the big rock hit, or if they were already on their way out. This paper looks at how the heads of these animals changed over space and time by looking at a large number of these from lots of different places. What they find is that there is a lot going on before the big rock hit. Some places are having their big animals look like they are having real problems, but in other places there seems to be a lot of new change in these big animals. It seems that this time before the big rock was a time when these big animals were going through a lot of changes. The big rock may have hit at a very bad time because things were not calm because of all of these changing going on. The second paper looks at animals living in water you can drink after the big rock hit. This paper finds a very large animal that breathes water head. Since this is a group of animals that are still around today, they can use the head to figure out how big the animal would have been, and they find that it would have been pretty big and also would have eaten other animals. This animal lived pretty soon after the big rock hit. This might mean that animals living on land and in the water that you can drink may have been doing a lot better than things living in the water you can not drink. If an animal was able to get that big eating other animals, it seems that these places were doing well. One of the ways animals respond when things get bad and foot is short is that they get smaller. Since we do not see that happening in this place, it could mean that places like this were not hit that bad when the rock hit. References: MacLaren, Jamie A., et al. "Global ecomorphological restructuring of dominant marine reptiles prior to the Cretaceous–Palaeogene mass extinction." Proceedings of the Royal Society B 289.1975 (2022): 20220585. Brownstein, Chase Doran, and Tyler R. Lyson. "Giant gar from directly above the Cretaceous–Palaeogene boundary suggests healthy freshwater ecosystems existed within thousands of years of the asteroid impact." Biology Letters 18.6 (2022): 20220118.

The gang discusses two papers that look at how combining fossil and modern data can affect our understanding of evolution. The first paper looks at studying primate biogeography, and the second paper studies how human interactions have affected dog morphology and disparity. Meanwhile, James finds a song he likes, Amanda could use some skin, and Curt appreciates how timely we've always been.

Up-Goer Five (Curt Edition):

Our friends look at two papers that show how using stuff from today and stuff from the past together can give you a better idea of what is going on with living things. The first paper looks at how we study where animals who look a lot like us lived in the past and how they came to live where they live today. The paper looks at how we can use old animals along with the animals around today to get a better idea of how the animals today got to where they are. That said, they do find that you need to take some care with the old animals you put in the study. You want to make sure that you really know what these old animals actually are. If not, it can make your study give weird answers. But, in the end, they show that it is better to use both old and today animals when you can.

The second paper looks at old dogs. Dogs can look like a lot of different things today. So people wanted to know if dogs could always look like so many different things in the past. So they found old parts of dogs from old human remains that date back to before people started to really change how dogs looked. They ran a study to see how different those dogs were from each other, and from dogs we have today, and also other things that are not dogs but are close to dogs. They find that these old dogs could be very different from each other, but not as different as the dogs we see today. They were a lot different from the other dog like animals too. So it shows that dogs were able to be very different in the past, but people have made this change even bigger.

References:

Wisniewski, Anna L., Graeme T. Lloyd, and Graham J. Slater. "Extant species fail to estimate ancestral geographical ranges at older nodes in primate phylogeny." Proceedings of the Royal Society B 289.1975 (2022): 20212535.

Brassard, Colline, et al. "Unexpected morphological diversity in ancient dogs compared to modern relatives." Proceedings of the Royal Society B 289.1975 (2022): 20220147.

The gang discusses two papers that look at the co-evolution of plants and herbivores. The first paper finds the earliest evidence of a unique type of insect herbivory in the fossil record, and the second looks at the evolutionary impact of the extinction of large herbivores on palm trees. Meanwhile, Curt recovers from COVID round 2, Amanda is a static character, and James finds that getting what he wants is almost worse than not getting it at all.

Up-Goer Five (Curt Edition):

Our friends talk about things that live in the ground and make their own food but are not able to move (like a tree and other things) and also the animals that eat these things. Some small animals eat the parts of trees that catch the sun but have this stuff that is supposed to get these small animals stuck if they try and eat these parts of the tree. The way that these small animals do this is either by cutting off the stuff that would get them stuck and then eating the rest of these parts that grab sun. We know that trees and other things like trees started to use this stuff a long time ago. This paper finds the first time that we know of in which these small animals were able to cut off the stuff that would get them stuck. They used the same ideas in the past that they use today, and it happened pretty close to when trees and other things like them started to use this stuff. This means that the trees and the small animals that eat them were changing with each other.

The second paper looks at how a type of tree that is not a real tree changed when the large animals that could have eaten it were not there. The people who wrote this paper had ideas about what changes could have happened when these not trees didn't have large animals around to eat them, but it turns out to have been a little different from what they might have thought. These not trees stopped making parts that would stop animals from eating them, but they didn't stop making big food. This might mean that big food is not just something that big animals can use, and that maybe small animals were eating the food and that would help the not tree to move its babies around.

References:

Onstein, Renske E., W. Daniel Kissling, and H. Peter Linder. "The megaherbivore gap after the non-avian dinosaur extinctions modified trait evolution and diversification of tropical palms." Proceedings of the Royal Society B 289.1972 (2022): 20212633.

McCoy, Victoria E., et al. "Oldest fossil evidence of latex sabotaging behavior by herbivorous insects." Review of Palaeobotany and Palynology 300 (2022): 104631.

The gang discusses two papers which use morphology to infer behavior in the fossil record. The first paper looks at the origins of the "killer whale" type morphology in fossil cetaceans, and the second paper describes the earliest example of a diurnal owl in the fossil record. Meanwhile, James proposes an unconventional workforce, Curt imagines the sea mammal revolution, and Amanda cuts the crap… out of her basement.

Up-Goer Five (Curt Edition):

Our friends talk about two papers that look at how things look and how we can use that to tell how animals might have lived in the past. The first paper looks at a group of animals with hair that breathe air but live their whole lives in water and do not have legs. There are lots of different types of these animals but one of these animals is named after being someone that kills. However, there is another group of these animals that look a lot like these animals that are named after killing but are not the same. This paper finds a really old one of these animals that looks like but is not one of these killing animals. These animals have things that make them eat in different ways than most of the animals with hair that live in water. This older animal may be the first time that these animals with hair who live in water were eating in this way. It also shows that this type of body that looks like these animals that are named for killing really did appear many times within the group.

The second paper looks at animals who fly that are usually out at night and kill very quietly. They find a very old one of these animals that is very complete and allows them to see lots of parts of the animal we usually do not get. These parts show that this animal may have actually been moving around during the day instead of at night, like most of the other animals in this group. They show that moving around in the day is something that a few of these animals today do and that it has appeared many times in the past. This animal might be the oldest one of these animals that lived in the day, and shows that, even though most of these animals today are out at night, the group has a lot more going on with whether or not these animals were out in the day or at night.

References:

Li, Zhiheng, et al. "Early evolution of diurnal habits in owls (Aves, Strigiformes) documented by a new and exquisitely preserved Miocene owl fossil from China." Proceedings of the National Academy of Sciences 119.15 (2022): e2119217119.

Bianucci, Giovanni, et al. "The origins of the killer whale ecomorph." Current Biology (2022).

The gang discusses two papers that show examples of exceptional preservation. The first paper looks at melanosome patterns in pterosaur barbules, and the second paper looks at a pathway for exceptional preservation in fossil spiders. Meanwhile, Curt (and his audio apparently) recover from COVID, James shares a story about renting, and Amanda tries to pronounce French. Up-Goer Five (Curt Edition): Our friends talk about two papers that look at animal parts that have held up really well for a long time. The first paper looks at soft things on the skin of angry flying animals that are not the same as flying animals that often can make happy sounds but are old brothers and sisters. The soft things on the skin of this animal have small things that make the soft things either light or dark. These small things look different from the other small things on the skin. We find this in big angry animals which are more close to the flying animals that make happy sounds. This might mean that the way these small things are put together on the animal might have appeared a lot more in the past than we thought. The second paper looks at small things with many legs that are usually really hard to find in rocks. However, we start seeing a lot more of them at a point. The ones that we do find look weird, and so this paper looked into how these small things that usually don't hold up in rocks managed to stay together in the rocks. They find that these small things with many legs fell into water that had a lot of other even smaller things made up of one part. These really small animals push out stuff that makes it easier for these really small animals to live there. This stuff changed the bodies of the small animals with many legs into something that wouldn't break down so easily. This is the first time this has been found in rocks, and it might be something that has happened more often than we know. References: Olcott, Alison N., et al. "The exceptional preservation of Aix-en-Provence spider fossils could have been facilitated by diatoms." Communications Earth & Environment 3.1 (2022): 1-10. Cincotta, Aude, et al. "Pterosaur melanosomes support signalling functions for early feathers." Nature (2022): 1-5.

The gang discusses two papers that look at the function of the ceratopsian frill. One paper looks at forensic evidence to understand the cause of an injury, and the other paper looks for clues to the adaptive origins of the Protoceratops frill. Meanwhile, Curt ruins the Muppets, James counts our cancellations, and Amanda is being silenced… by Discord.

EDITOR'S NOTE: To head off any discussions about food science crimes committed by this podcast, we have been made aware by reviewers of an early draft of this podcast (i.e. patreon members) that a discussion on rice may have implied that glutinous rice had "gluten" in it. This is completely incorrect. Glutinous rice is just named that way because it is sticky. As an eater of many types of glutinous rice who is married to a registered dietician, your humble editor was deeply ashamed that such horrible misinformation had made it into a draft of this podcast. The ethical decision would be to remove this discussion to prevent the spread of misinformation. However, that would take work... so instead he decided not to bother. What is the context of the conversation? When in the podcast does this conversation happen? Who implied this food crime? Did this conversation actually happen at all or is the person on the patreon just pulling the editor's leg? All of these questions would require just a modest amount of work to investigate and so they will remain forever unanswered. Was this important enough to warrant such a long note? Probably not, but your humble editor is recovering from COVID and so is filling the boredom by extending this rather minor correction into an overblown bit. If you would like to see early drafts of this podcast, go to www.patreon.com/palaeoafterdark.

Up-Goer Five (Curt Edition):

Our friends talk about a group of big angry animals that everyone likes with a fun thing on their heads. Both of these papers look at different types of these animals but at the end of the day, the papers are all trying to figure out how these animals used that fun thing on their heads. The first paper looks at an animal that had a small part missing in the fun thing on its head. The paper tries to find out why this animals is missing this small part. Some people have said that the small parts could go away when the animal gets bigger, but we have already shown in another one of these shows that this does not happen. So it seems that instead this animal probably got hurt. It seems that the animal was hit with something long from the back. This is different from a lot of the ways people have said this animal would usually get hurt with the fun thing on its head.

The second paper looks at another animal from this group that is far older and tries to see if they can figure out what the animals could have used their fun things on their head. They have an idea that it could be used to get other animals to love them. In order to see if that is the case, they come up with other things they should see if this was true. They look at a lot of these animals and find that some of these things are true but other things are not. So it seems that they really could have used these fun things on their head for finding love, but they also say that it might be for other things. The point is, it seems like a pretty good case could be made that they used it for love.

References:

Knapp, A., R. J. Knell, and D. W. E. Hone. "Three-dimensional geometric morphometric analysis of the skull of Protoceratops andrewsi supports a socio-sexual signalling role for the ceratopsian frill." Proceedings of the Royal Society B 288.1944 (2021): 20202938.

D'Anastasio, Ruggero, et al. "Histological and chemical diagnosis of a combat lesion in Triceratops." Scientific reports 12.1 (2022): 1-8.