The gang discusses two papers that look at some exceptionally preserved juvenile fossil specimens and the interesting clues these fossils give to the ontogeny of extinct groups. The first paper is the current oldest preserved tadpole, and the second paper is an exceptionally preserved mummified sabre-toothed cat. Meanwhile, Amanda becomes light, James is visited, and Curt is left in the dust and the filth.

Content warning: This episode contains covers some potentially dark material given that these fossils are juveniles. The following time stamps represent some of the more sensitive moments in which the group make morbid jokes about the subject matter.

6 min 3 sec to 6 min 39 secs.

58 min 13 seconds to 58 min 29 secs

Up-Goer Five (Curt Edition):

The friends talk about two papers that show some kids from animals groups that are no longer around. These papers are cool because they show how animals from a long time ago changed as they got older. The first paper looks at the kid of an animal group that changes a lot from a thing that moves through water to a thing that jumps on the ground. This kid is somewhere in the middle of jumping and moving through water. This is the oldest of this type of kid we have found so far. The group today is different because they go through this really big change. This paper shows that they were going through this really big change a long long time ago and shows that this change probably happened early on in their time line.

The second paper looks at a kid that is from a group of animals with hair and long teeth. This kid was in ice and so we have a lot of things that we would not get that are soft. This is the first time we have seen the soft parts for this age of this animal and it shows us that lots of things we see in the grown animals were also there when they were kids.

References:

Chuliver, Mariana, et al. "The oldest tadpole reveals evolutionary stability of the anuran life cycle." Nature (2024): 1-5.

Lopatin, A. V., et al. "Mummy of a juvenile sabre-toothed cat Homotherium latidens from the Upper Pleistocene of Siberia." Scientific Reports 14.1 (2024): 28016.

The gang discusses two papers that look at the evolution of photosynthesis in different groups. The first paper looks at what might be the first fossil evidence of thylakoids, and the second paper finds evidence for photosynthesizing symbiotes in Devonian fossil corals. Meanwhile, Amanda is making a lasagna, James has a lot of opinions about lasagna (~10 minutes until we actually get to the paper), and Curt is all about those sponges.

Up-Goer Five (Curt Edition):

The friends talk about two papers that look at how some types of living things can make food from the sun. The first paper looks at these very very old things that are very very very small. Inside these things they find very very very small parts of things that are used today by some living things to help make food from the sun. This might be the oldest one of these things that we have ever found, and it makes it so that we can see how things might have gotten better at making food from the sun over time.

The second paper looks at old animals that live in the big blue wet thing that all live close together and make big hard parts that make walls in the water. These old animals are like the ones we see today but they are a group that is not around anymore. Groups today have friends that help make food from the sun for them. This paper looks to see if the old animals had those friends (or friends like them) too. They find that animals today keep some bits of things they do not usually want so that their friends can eat them. This can be seen in the hard parts they make. When they looked at the hard parts of the old group of animals, they saw that they were doing this too. This means that these animals were keeping food for friends just like that animals we see today.

References:

Demoulin, Catherine F., et al. "Oldest thylakoids in fossil cells directly evidence oxygenic photosynthesis." Nature 625.7995 (2024): 529-534.

Jung, Jonathan, et al. "Coral photosymbiosis on Mid-Devonian reefs." Nature (2024): 1-7.

Sausage, Biscuits, Eggey, and Crankshaft make their way into the big mansion. Will they be able to pull off the heist of the century and deliver a perfect Christmas for the raccoons of the junkyard, or will they all go down in a blaze of glory?

"Sergio's Magic Dustbin" and “Silent Night” from Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0/

Check out “Raccoon Sky Pirates” on itch,io https://hecticelectron.itch.io/raccoon-sky-pirates

Sausage, Biscuits, Eggey, and Crankshaft board the Dumpster Fire and prepare for a holiday adventure... despite the wishes of an unsuspecting populace.

"Sergio's Magic Dustbin" from Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0/

Check out “Raccoon Sky Pirates” on itch,io https://hecticelectron.itch.io/raccoon-sky-pirates

James, Amanda, Curt, and Ants all get together to plan a holiday raccoon heist. What could possibly go wrong?

"Sergio's Magic Dustbin" from Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0/

Check out “Raccoon Sky Pirates” on itch,io https://hecticelectron.itch.io/raccoon-sky-pirates

The gang discusses two papers that look at patterns of mosaic evolution, one paper looking at cat evolution and the other paper looking at bird ecomorphy. Which means the gang talks about Amanda’s two favorite taxonomic groups. Meanwhile, Curt enjoys some realistic bird calls, Amanda remains a threat, and James provides relevant “facts”.

Up-Goer Five (Curt Edition):

The friends take a look at how animals change over time and how the parts of the animals might change in different ways at different times. The first paper looks at cats and things that are like cats, and they look at the parts of cats and how they have changed. What they find is that the different parts are changing in different ways across different groups of cats and cat like things.

The second paper looks at the neck of animals that move in the air. The paper is looking to see if the reason why these necks change the way they do are because of how they are trying to get food, which is what people thought might be true but no one has looked to see if it is true. A lot of work is done and it does seem that the necks change in a lot of ways that are different for different groups, but it does seem that a lot of these changes are because of how the animals try and look for food.

References:

Barrett, Paul Z., and Samantha SB Hopkins. "Mosaic evolution underlies feliform morphological disparity." Proceedings of the Royal Society B 291.2028 (2024): 20240756.

Marek, Ryan D., and Ryan N. Felice. "The neck as a keystone structure in avian macroevolution and mosaicism." BMC biology 21.1 (2023): 216.

The gang discusses two papers that detail interesting findings about the soft tissues of extinct arthropods. The first paper does a detailed study of the limbs attached to the trilobite head. The second paper describes the newly discovered head of the ancient myriapod Arthropluera, and discusses the larger implications this fossil has for the evolution of millipedes. Meanwhile, Curt explores new advertising ventures, Amanda unpacks automotive anxiety, and James has no ethical complications to report concerning this podcast.

Up-Goer Five (Curt Edition):

The friends look at two papers that look at parts of dead animals that have lots of parts that repeat over and over again and take off their skin every time they get bigger. The first paper looks at a group of these dead animals that are no longer around but are found a lot in the past. This paper shows that the number of legs in the head is different than we thought it was. They show that there are five legs in the head, and that it was hard to see in a lot of these animals because of the ways that we get these animals in the rocks makes it harder to see.

The second paper looks at an animal that we think is a lot like animals we see today with long bodies and two legs on each part. But we never actually found the head of these animals. This paper finds the head and it helps to show us a lot of cool things about not just these animals in the past, but also how these animals have changed over time. This helps us understand why the groups we have today are the way that they are.

References:

Lhéritier, Mickaël, et al. "Head anatomy and phylogenomics show the Carboniferous giant Arthropleura belonged to a millipede-centipede group." Science Advances 10.41 (2024): eadp6362.

Hou, Jin‐bo, and Melanie J. Hopkins. "New evidence for five cephalic appendages in trilobites and implications for segmentation of the trilobite head." Palaeontology 67.5 (2024): e12723.

The gang discusses two papers that look at examples of soft tissue preservation during the Cambrian. The first paper is a deep dive into the sedimentology and paleoenvironment of the Emu Bay Shale. The second paper makes some interesting claims about soft tissue preservation in a marginal marine environment. Meanwhile, James needs some shortcuts, Curt is locked up, and Amanda should be blamed for everything that happened here.

Up-Goer Five (Curt Edition):

The friends look at two papers that look at animals from a long long time ago that lived in the water and were soft but were able to be found in rocks. The first paper looks at a place where there are a lot of animals found in rocks but the types of animals are different from other places around the same time. This paper looks at what the place was like at that time and they see that this was a place where a long line of water that you can drink made its way into the big water that you can not drink. The second paper made us all sad.

References:

Naimark, E. B., A. V. Sizov, and V. B. Khubanov. "Kimiltei Is a New Late Cambrian Lagerstätte with the Faunistic Complex of Arthropods (Euthycarcinoidae, Synziphosurina, and Chasmataspidida) in the Irkutsk Region." Doklady Earth Sciences. Vol. 512. No. 1. Moscow: Pleiades Publishing, 2023.

Gaines, Robert R., et al. "The Emu Bay Shale: A unique early Cambrian Lagerstätte from a tectonically active basin." Science advances 10.30 (2024): eadp2650.

The gang discusses two papers that look at two Lagerstätten (fossil localities of exceptional preservation). The first Lagerstätte is a unique complex early Triassic community found near the equator, and the second Lagerstätte is a collection of exceptional trace fossils from the Pennsylvanian. Meanwhile, James is convinced in the existence of a town that doesn’t exist, Amanda takes an unexpected break, and Curt once again needs to be redacted.

Up-Goer Fiver: (Curt Edition)

The friends talk about two papers that look at times when there was a lot of things in the rocks that we do not get in the rocks during most times, and these times can let us know that there were a lot more things were living at this time. The first paper talks about rocks during a time when usually there is not a lot going on because it was just after a time that most things died. Most rocks at this time do not show a lot of things living. These rocks are cool because they are just after the time almost everything died and they show the things that we know lived through that, and that they are all together in a way that looks like the groups of animals we see in rocks way later. The second paper looks at changes in rocks that are because animals move through or on the ground and that gets in the rocks. This area has a lot of these rocks with the bits of animals moving which lets us know a lot about what things were doing on land a long time ago.

References:

Dai, Xu, et al. "A Mesozoic fossil lagerstätte from 250.8 million years ago shows a modern-type marine ecosystem." Science 379.6632 (2023): 567-572.

Knecht, Richard J., et al. "Early Pennsylvanian Lagerstätte reveals a diverse ecosystem on a subhumid, alluvial fan." Nature Communications 15.1 (2024): 7876.

The gang looks at two papers that compare similar structures in unrelated animals to see if there might be evidence of convergence. The first paper compares Spinosaurus to phytosaurs and the second paper compares the hyoid bone of ichthyosaurs and toothed whales. Meanwhile, Curt will try it, James waits for something that never happens, and Amanda has a surprise.

Up-Goer Five (Curt Edition):

The friends talk about two papers that look to see if animals that are not close are the same in ways because of what they do. The first paper looks at too old and dead big angry animals. Both of these animals look like angry animals today that move in water, and so this paper is looking to see if maybe they were both doing the same thing as what we see today. The paper doesn't come to a strong end, but it looks like maybe these things are doing things that maybe are not always the same as the things that live today that they look like.

The second paper looks at two animals that need air but move in the water all the time, one group that is living today and one that has been dead for a very very long time. There is a hard part in them that in the groups that are living today they can use to suck in water to get food to them. People had thought that the old group could have done this too. They looked at this hard part that lets things suck, and they found that the hard part in this old dead group would not let them suck. So these old dead animals would have to get food in a different way than the group living today.

References:

Yun, Chan-gyu. "SPINOSAURS AS PHYTOSAUR MIMICS: A CASE OF CONVERGENT EVOLUTION BETWEEN TWO EXTINCT ARCHOSAURIFORM CLADES." Acta Palaeontologica Romaniae 20.1 (2024).

Delsett, Lene Liebe, et al. "Is the hyoid a constraint on innovation? A study in convergence driving feeding in fish-shaped marine tetrapods." Paleobiology 49.4 (2023): 684-699.