Palaeo After Dark (general)

The gang discusses two papers that use fossil evidence to determine the past ecology and niche-space of past organisms, specifically dodos and hyenas. How can we use information from bones to interpret diet, life cycle, and behaviors of long dead animals? Also, James decides to start Skynet on the grounds that they will let him become a weather controlling tiger-bot, while Amanda and Curt draw hard lines in the sand about Don Bluth cartoons. 

 

Up-Goer Five (James Edition):

The group looks at two papers that are interested in seeing how things lived. The first is cutting into the inside hard parts of animals with that should fly but could not fly and are in the same family as animals that can fly and live with people in cities. These animals died when people came to their rock in the big water that you can not drink with lots of bad friends. The people that came to the home of these animals did not care about them much, and so the words we have from them are not very good and often do not agree. The study looks at the hard parts and the words of the people to see how these animals lived. They show that the animals grew quickly and changed their clothes a lot over the year which is why different people thought they looked different, and that they laid their round baby boxes during the part of the year when there was not bad sky stuff.

The next study looks at the teeth of cats that want to be dogs that are today only found in the big place where the rains are down but in the past were found in many places that people lived. They want to see if these cats that want to be dogs eat the same thing at different points in time. They show that the cats that want to be dogs eat different things today than they used to, and that maybe this is because there are very big cats that are definitely cats in the big place where the rains are down that stop them getting other food.

 

References:

 DeSantis, Larisa RG, et al. "Assessing niche conservatism using a multiproxy approach: dietary ecology of extinct and extant spotted hyenas." Paleobiology 43.2 (2017): 286-303. 

 Angst, D., et al. "Bone histology sheds new light on the ecology of the dodo (Raphus cucullatus, Aves, Columbiformes)." Scientific Reports 7 (2017). 

Direct download: Podcast_121_-_Reconstructing_the_Niche.mp3
Category:general -- posted at: 3:00am EDT

The gang discusses two papers that deal with different examples of convergence. The first discusses how brood parasite female cuckoos mimic birds of prey, and the second paper discusses convergent morphological evolution in early tetrapodomorph fishes. What do these two papers have in common. you may ask? Both discussions have Amanda cheerfully yelling the word "Convergence!"

Meanwhile, Amanda narrowly avoids drunk Amazon shopping, James demands truth in advertising, Curt doesn't believe that these papers are remotely related in any way, and everybody gets very easily distracted by the prospect of fire-belching furnaces and knife-wielding murderbots. <EDITOR'S NOTE: The group start talking about science about 10 minutes in>

 

Up-Goer Five (Curt Edition): 

The group looks at two papers where the same things keep happening to many different animals. The first paper looks at an animal that can fly and is a bad mom that leaves the kids with some other flying mom so she does not have to raise them. This flying bad mom can pretend to be something else and kind of looks like something else that is big and angry. When the flying bad mom drops the kids at the home of the other flying mom, she pretends to be a very big and angry flying thing by screaming as she leaves the home of the other flying mom. People showed that the sound of the bad mom screaming sounds just like the big angry thing she is pretending to be, which makes the other flying moms scared so they do not know that the kids have been left at their home. The kids then eat the other flying moms out of house and home.

The other paper looks at animals that are in the water but could sometimes come out on the land from a long time ago. As time went on, more of these animals spent more time out on land than on the water, and they also changed how they looked. This made us think that the things spending more time on land changed in ways for them to spend more time on the land. But this new animal shows that those changes happened in things that didn't spend as much time on land, so maybe the changes aren't just because things were on the land so much.

 

References:

York, J. E., & Davies, N. B. (2017). Female cuckoo calls misdirect host defences towards the wrong enemy. Nature https://doi.org/10.1038/s41559-017-0279-3

Zhu, Min, et al. "A Devonian tetrapod-like fish reveals substantial parallelism in stem tetrapod evolution." Nature Ecology & Evolution (2017): 1.

Direct download: Podcast_120_-_Something_Something_Convergence.mp3
Category:general -- posted at: 3:00am EDT

The gang discusses two papers that look at the complex issues surrounding the identification of sexual dimorphism in archosaurs (e.g. birds, dinosaurs, and alligators/crocodiles). Meanwhile, James has very strong opinions about Fat Tire beer, Amanda becomes lost in independent research, and Curt accidentally tears the podcast apart.

 

Up-Goer Five (James Edition):

The group looks at two papers that want to see whether animals that lived a long time ago are boys or girls. The first paper is looking at lots of small animals that could fly and had hard mouths. We find them in small, not so small, and big, and it has been suggested that the big ones were boys, the not so small ones were girls, and the small ones were young. Some of them have big back ends, and it was thought that maybe those that had big back ends were boys and those that did not have big back ends were girls. The paper thinks that maybe both boys and girls had big back ends, because they find big back ends on the young ones. The group however have seen another paper that thinks that boys did have big back ends and girls did not have big back ends and the small ones were actually a different type of flying animal with hard mouths.

The second paper is looking at trying to tell if big angry animals without hair were boys or girls. To do this they look at big angry animals that are around today and animals with hard mouths that are too big to fly that are around today. They show that big angry animals and animals with hard mouths that can sometimes fly grow different, and if you did not know which ones were boys or girls it is very different to tell which of the big angry animals are boys and girls. They show that most big angry animals without hair from a long time ago grow like big angry animals today, and so we should wait for a lot of facts before deciding if they are boys or girls, and that when we have thought we have found different things between boys and girls in the past we may have been looking at grown ups and babies.

 

References: 

 Hone, David WE, and Jordan C. Mallon. "Protracted growth impedes the detection of sexual dimorphism in non‐avian dinosaurs." Palaeontology 60.4 (2017): 535-545. 

 Peters, Winfried S., and Dieter Stefan Peters. "Life history, sexual dimorphism and ‘ornamental’feathers in the Mesozoic bird Confuciusornis sanctus." Biology letters (2009): rsbl20090574. 

Direct download: Podcast_119_-_Dimorphic_Dinosaurs.mp3
Category:general -- posted at: 3:00am EDT

The gang discuss two papers that attempt to resolve the taxonomic placement of animals with complex or confusing morphologies. Also, they somehow go off on a tangent about careers in academia, publish or perish, and the various lengths people can go to try and maximize their research output. Meanwhile, Amanda has some issues with her light sockets, James tries to pass off "facts"about rats, Curt makes references to 90's cartoons, and everyone greets our new guest, the "Pony".

 

Up-Goer Five (James Edition): 

The group looks at two studies where animals that were thought to be one thing were shown to be another. The first paper looks at a very old animal known from three parts. One part was thought to be a soft animal that moved in the water and had the same thing for a mouth and a bottom, another part was thought to be an animal that hid in a hard house and grabbed food as it passed, and another was thought to be something that has a soft thing in it for sending news from end to end. The new study shows that these are all the same thing, and that is part of a big group of animals that can move in water or stick to rocks and attack things with small arms.
The other study is looking at big angry animals with no hair, especially one big angry animal that it is not known where it should go. The big angry animal is not that big and not that angry, and seems to be like both big angry animals with no hair that ate other animals and big angry animals with no hair that ate green things that do not move. The new study shows that it is part of one of the groups of big angry animals with no hair that eats green things that do not move, but the ones that have big heads and short necks. Parts of it look like big angry animals with no hair that eat other animals because it is an early part of the big angry animals with no hair that eat green things that do not move that have big heads and short necks even though we find it after we find some of its friends.

References:

Ou, Qiang, et al. "Three Cambrian fossils assembled into an extinct body plan of cnidarian affinity." Proceedings of the National Academy of Sciences(2017): 201701650. 

Baron, Matthew G. and Barrett, Paul M. "A dinosaur missing-link? Chilesaurus and the early evolution of ornithischian dinosaurs" Biology Letters(2017): https://dx.doi.org/10.6084/m9.

Direct download: Podcast_118_-_Dealing_with_Problematica.mp3
Category:general -- posted at: 3:00am EDT

The gang discuss two papers that study how the geographic ranges of turtles and frogs changed through time, and how these changes affected their ecology and evolution. Also, James drinks what he presumes is ground horse, Curt goes full Ian Malcolm, Amanda shares life lessons about furniture, and everyone imagines what turtle they are. [Editor's note: The actual science starts about 13 minutes in, I just didn't have the heart to cut it down.]

 

Up-Goer Five (Amanda and James Edition):

Today our friends talk about animals with hard backs and no hair, and also animals that jump and have little skin. The group looks at two studies that look to see whether where animals are and have been is important. We talk about how animals with hard backs and no hair used to live in many, many places. Today they live in less places. Maybe some day they will live in more places again if it gets warm because of people. But maybe not because some animals with hard backs and no hair do need it to be wet. And if it is not wet when it gets warm again then they will not be able to live in more places again. We don't know. Being wet does seem to matter a lot, though. With animals that jump and have little skin, maybe they changed in place or maybe they went all over the place and changed as they went. We read that people think that they did not change as they went, but rather changed in one place and then went to other places. 

 

References:

Waterson, Amy M., et al. "Modelling the climatic niche of turtles: a deep-time perspective." Proc. R. Soc. B. Vol. 283. No. 1839. The Royal Society, 2016. 

Chan, Kin Onn, and Rafe M. Brown. "Did true frogs ‘dispersify’?." Biology Letters 13.8 (2017): 20170299. 

Direct download: Podcast_117_-_Hero_Terrapins_and_Fighting_Frogs.mp3
Category:general -- posted at: 3:00am EDT

The gang discuss two papers that offer new evidence which re-contextualizes our understanding of the evolutionary history of two important Mesozoic groups, dinosaurs and marsupials. Meanwhile, Amanda comes up with a terrible/great new idea for liquor consumption, Curt consistently offers bad advice to his friends, and James cracks open a bottle of sangria and then everything gets a bit fuzzy. Can you guess that this was the fourth podcast recorded in a single week? Can you hear the life drain from James? (Editor's Note: The "science" starts 13 minutes in. Apologies, we will be better in the future. [Editor's Editor's Note: Probably not.])

 

Up-Goer Five (Amanda Edition): 

Today our friends talk about very large animals with no hair that everyone loves but our friends don't care about, and also funny animals with hair that are not like us because they do not have big babies. It turns out the very large animals with no hair that everyone loves are all brothers and sisters in a very funny way, not like we used to think at all. The very large animals with no hair that everyone loves have three kinds: long necks that eat leaves, ones that eat other animals, and ones that eat leaves but do not have long necks. We thought that the ones that had long necks and the ones that eat other animals were close brothers and sisters. But it turns out they might not be. The ones with long necks might be the oldest brothers and sisters, then the ones that ate leaves but did not have long necks, and then the ones that ate other animals. With the funny animals with hair that are not like us because they have small babies, they were thought to have started in places other than where our friends live. But it turns out that maybe they actually started where our friends live, and not where other people live across the big waters. 

 

References:

 Baron, Matthew G., David B. Norman, and Paul M. Barrett. "A new hypothesis of dinosaur relationships and early dinosaur evolution." Nature 543.7646 (2017): 501-506. 

 Wilson, Gregory P., et al. "A large carnivorous mammal from the Late Cretaceous and the North American origin of marsupials." Nature Communications 7 (2016). 

Direct download: Podcast_116_-_Changing_Relationships_Dinosaurs_and_Marsupials.mp3
Category:general -- posted at: 3:00am EDT

The gang discuss two papers that discuss the methods we use to determine how different things are from each (i.e. disparity). In particular, do variations in parts of an animal give us a good sample of the morphological variability of the total animal? Meanwhile, Amanda wants a whale, James has strong opinions about vertebrae, and Curt tries to narrow in on what Amanda views as "cute".

 

Up-Goer Five (James Edition):

The group looks at two studies that want to see if we can say how different animals are. There are many ways that we can try to see how animals are different from each other. The first paper looks at two ways of seeing if animals are different, one by looking at how points on the animals change between them and another by looking at what parts the animals have. The paper shows that the both types of study give the same answer, which is good news.

The second paper wants to see if we get the same answer for how animals are different from each other when we look at only one part of the animal instead of looking at the whole animal. This study also shows that when you look at part of an animal, you get the same answer as when you look at the whole animal. This is also good news! There's lots of good news, let's have a party.

 

References:

Hetherington, Alexander J., et al. "Do cladistic and morphometric data capture common patterns of morphological disparity?." Palaeontology 58.3 (2015): 393-399. 

 Hopkins, Melanie J. "How well does a part represent the whole? A comparison of cranidial shape evolution with exoskeletal character evolution in the trilobite family Pterocephaliidae." Palaeontology 60.3 (2017): 309-318. 

Direct download: Podcast_115_-_Amanda_Now_Wants_Tiny_Whales_to_be_a_Thing.mp3
Category:general -- posted at: 3:00am EDT

The gang discuss two papers that describe the life strategies of trilobites, a diverse and charismatic group of extinct arthropods. Specifically, they look at two papers that look at enrollment and movement of trilobites. Meanwhile, Amanda educates James on the nature of pain, James envisions Curt's inevitable end, and Curt invents a hockey/extinct arthropod family film.

 

Up-Goer Five (James Edition):

The group looks at two papers that look at old animals with many legs that live in the bad drink water place and are made out of rock. These animals are all over the place and are good to study much like small animals with hair and big ears are used today. One paper makes pictures of the old animal with many legs on the computer to see how they turn into a ball. This paper is very easy to understand and shows that these animals can turn into a ball in a number of different ways and that they started doing these different ways a number of different times. However, once they have made this change they seem to stick with it. The second paper is not very easy to understand. It looks at where these old animals with many legs form lines and tries to work out whether they are forming lines so it is easier for them to walk. A lot of numbers are used to work out how easy it is for them to walk, but it is not clear what the numbers say. They suggest the lines these animals with many legs make are the same as ones people that ride things with two round moving things instead of legs make, but this just makes things more confusing.

 

References: 

Trenchard, Hugh, Carlton E. Brett, and Matjaž Perc. "Trilobite ‘pelotons’: possible hydrodynamic drag effects between leading and following trilobites in trilobite queues." Palaeontology (2017). 

 Esteve, Jorge, et al. "Modelling enrolment in Cambrian trilobites." Palaeontology 60.3 (2017): 423-432. 

Direct download: Podcast_114_-_Trilobites_Mice_of_the_Paleozoic.mp3
Category:general -- posted at: 3:00am EDT

The gang discuss the concept of the body plan, or "bauplan", and what it means for our understanding of evolution. When in the evolutionary history of a group do the morphological characteristics we associate with that group become fixed? Meanwhile, Amanda details the exploits of mischievous crows, Curt explains our free-to-play academic futures, and James educates America on British society. Also, we start talking about science about 9 minutes in.... it's one of those podcasts.

If you want to support the podcast, you can go to www.patreon.com/palaeoafterdark to find out more.

 

Up-Goer Five (Curt Edition):

Our friends talk about body plans. Yes, we can say body plan in this. Some animals and not animals are almost the same, and people wonder if it is because those animals and not animals are brothers and sisters but bigger. Also, people wonder when these animals and not animals first became the same, because they started out not the same and became more same over time. Does it matter that these animals and not animals are the same? Why are they the same? It turns out that some animals that are small with weird mouths were more different in the past than we thought, and they got their weird mouth before they became really same. Also big animals that were brother and sister but bigger to animals that would walk and maybe fly some day were very different in the past.

 

References: 

Aria, Cédric, and Jean-Bernard Caron. "Burgess Shale fossils illustrate the origin of the mandibulate body plan." Nature 545.7652 (2017): 89-92. 

 Nesbitt, Sterling J., et al. "The earliest bird-line archosaurs and the assembly of the dinosaur body plan." Nature 544.7651 (2017): 484-487. 

 

"Brightly Friendly" Kevin MacLeod (incompetech.com)

Licensed by Creative Commons: By Attribution 3.0

http://creativecommons.org/licenses/by/3.0/

Direct download: Podcast_113_-_Whats_In_a_Bauplan.mp3
Category:general -- posted at: 3:00am EDT

The gang discuss two papers that use biogeochemical evidence to determine the diets of two specialist species. Just how restricted are the diets of these species? Meanwhile, Amanda finds a new pet she desperately needs, James copes with a changing environment, and Curt  gives James some advice on social situations.

If you want to support the podcast, you can go to www.patreon.com/palaeoafterdark to find out more.

 

Up-Goer Five (Amanda Edition):

Today our friends talk about animals that can only do one thing or animals that can do many things. Most people think that animals that can only do one thing are not very good and will die fast. They also think that animals that can do many different things are good and will live a long time and have lots of babies. One paper our friends read actually says that sometimes animals look like they can do only one thing, but really they just really, really like to do that one thing, and if they have to they will do something else so that they can live. The other paper says that big stupid black and white animals that are not good are really not good and have been not good for a long time. A long time ago, there were even very small big stupid black and white animals that were not good, and even then they were not good. 

 

References: 

 Terry, Rebecca C., Megan E. Guerre, and David S. Taylor. "How specialized is a diet specialist? Niche flexibility and local persistence through time of the Chisel‐toothed Kangaroo Rat." Functional Ecology. 

 Stacklyn, Shannon, et al. "Carbon and oxygen isotopic evidence for diets, environments and niche differentiation of early Pleistocene pandas and associated mammals in South China." Palaeogeography, Palaeoclimatology, Palaeoecology 468 (2017): 351-361. 

 

"Scheming Weasel slower" Kevin MacLeod (incompetech.com)

Licensed by Creative Commons: By Attribution 3.0

http://creativecommons.org/licenses/by/3.0/

Direct download: Podcast_112_-_How_Specialized_Are_Specialists_.mp3
Category:general -- posted at: 3:00am EDT