Podcast 178a - "Paradise Falling" Part 1

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The gang celebrates the end of the year by taking another break to play Fiasco, a crime/noir storytelling game by Bully Pit Games. This campaign will be broken into two parts.

The afternoon sun cast long, hazy blades of light across the linoleum floor of the Blue Label Diner in downtown Paradise Falls. Bill Larsen took a moment to stretch his aching back before hunching again to buff the counter with his cleaning rag. With weary eyes, he turned his attention back to the out-of-towner who was furtively sipping her coffee. She pulled out a notebook and pen from her jacket pocket and set them expectantly on the counter, waiting for Bill to speak.

“Do ya want some apple pie? Best in town.” No other restaurant in Paradise Falls sold apple pie, and Bill knew that.

The woman shook her head, “Mr Larsen, I’m just here to learn the facts about what happened in your town. So please…. from the beginning…”

“How did it all happen? Well that’s a long story.” He paused and gave a winking smirk “Ya sure ya don’t need somethin’ more to eat?”

The woman tapped on her notebook.

“Let’s see, well to understand any of it ya have to go back to the beginning. Ya see, first came the storm. Terrible winds ripped through our poor town like the gates of hell just opened up. Thank God most of the town was spared. Well…. except for the Tully farm. Such a waste really. Beautiful property that farm, and been with the family for generations. Pity Miss Tully had to sell. But in the long run, sad as it is to say, and I do feel just awful sayin’ it, but in the long run I think ya gonna see that sellin’ that farm was the best thing that ever happened to this town.”

The door to the Blue Label Diner swung open as another patron entered. With him came billowing black smoke from the outside, some of the thick soot that was beginning to blanket the entire downtown; a new daily ritual for Paradise Falls. The sunlight through the windows began to wane as the world outside became consumed in an ever thickening dark cloud of chemicals. But inside the diner there was coffee and pie.

"Paradise Falling" is a surreal tale of paranoia, failure, and cold hard capitalism.

"Andreas Theme" Kevin MacLeod (incompetech.com) 
Licensed under Creative Commons: By Attribution 3.0
http://creativecommons.org/licenses/by/3.0/

Podcast 177 - Grow a Spine

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The gang discusses two papers that look at how the morphology of tetrapods (animals with four limbs and a backbone) has changed over time. One paper looks at how dinosaur jaws are related to diet preferences, and the other paper looks at how spines have changed as tetrapods diversified through time. Meanwhile, James talks Star Trek, Curt gives some consumer advice, and Amanda would rather not talk about cowboys.

Up-Goer Five (James Edition):

This week the group look at two papers that are looking at different ways that animals get more different. The first paper is looking at the mouths of big angry animals with no hair. The big angry animals with no hair that eat other animals and get big have the least different mouths from each other, but those that are small and eat other animals have very different mouths from one another, and those that eat living things that make their own food or both other animals and living things that make their own food have the most different mouths from one another. We see the same thing no matter how we decide how different mouths are.

The other paper is looking at the line of hard bits in the back of animals that do have hair to see if they get more different over time and do different things along the same line of hard bits. We find out that the line of hard bits do get more different over time, and that the reason they get more different may be because the animals with hair start to breathe more air.

References:

 Jones, Katrina E., Kenneth D. Angielczyk, and Stephanie E. Pierce. "Stepwise shifts underlie evolutionary trends in morphological complexity of the mammalian vertebral column." Nature communications 10 (2019). 

 Schaeffer, Joep, et al. "Morphological disparity in theropod jaws: comparing discrete characters and geometric morphometrics." Palaeontology (2019). 

Podcast 176 - Much Ado About Teeth

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The gang discusses two papers that look at changes in teeth through time. The first paper looks at the earliest example of heterodont teeth in tetrapods, and the second paper looks at how different mammal groups build sabre tooth morphologies. Meanwhile, James has unique ideas for building worker morale, Amanda accidentally makes a pie faux pas, and Curt is friend to gelfling.

Up-Goer Five (Amanda Edition):

Today our friends talk about teeth. Wow, teeth is one of the ten hundred most used words. Cool. So some things have teeth that are all the same kind. Most of the very early things with four feet that go on long have teeth of all the same kind. But there is an early thing with four feet that goes on land that we have known about for a long time that was never really looked at too close and now we see that it has teeth that are big and round and teeth that are small and pointed. It was probably eating things that were very hard and needed to be broken up before it could eat them. What is cool is that there are lots of animals from the same place at the same time that also show this kind of eating thing, where they must have been eating things that were very hard like rock and had to be broken up before they could be eaten. Our friends also talk about animals with hair that had very very long pointed teeth in the front of the mouth. It turns out that these teeth grow in a very different way. Animals with hair only grow teeth two times, and the back teeth only grow in one time. Usually the back teeth grow in last. But these animals had their very very long pointed front teeth grow in last. And they grow in funny. They grow in along the inside of the old teeth, until they are as much as the old teeth, then the old teeth fall out. This might mean that these teeth show up in different animals with hair totally on their own over and over and over again many times, which is cool.


References:

Clack, Jennifer A., et al. "Acherontiscus caledoniae: the earliest heterodont and durophagous tetrapod." Royal Society open science 6.5 (2019): 182087. 

 Wysocki, Matthew Aleksander. "Fossil evidence of evolutionary convergence in juvenile dental morphology and upper canine replacement in sabertooth carnivores." Ecology and Evolution (2019). 

Podcast 175 - Big Data Studies

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The gang discusses two papers that use large data sets to look at big picture patterns in evolution and ecology. Specifically, they look at one paper that explores brachiopod shell thickness in relationship to environmental preferences during the Late Ordovician mass extinction, and another paper that looks at the evolution of using the tail as a weapon in vertebrates. Meanwhile, James is eternally “young”, Curt invents unique ecological roles for Stegosaurus, and Amanda enables the worst type of ASMR (for those who cannot handle food sounds in microphones, skip 47:57-48:54).

Up-Goer Five (Curt Edition):

Our friends talk about two papers that bring together a lot of facts about things to say something about how living things have changed over time. The first one looks at hard rock like things that take food out of the water. This paper looks at how thick the hard parts of these things were and it focuses on a time when these things went through a real bad time and a lot of them died. While the paper finds a lot of interesting things, one of the big things they find is that some of the animals that pull food out of the water all made really thicker hard parts than the other types of animals that pull food out of the water. These animals that made really thick hard parts were also the ones that were hurt when a real bad time happened.

The second paper looks at animals that have a long part coming off their bottom. This paper looks at animals which use the long part on their bottom to hit things. There are lots of different ways animals with long parts coming off their bottom can use that long part to hit things, and this paper looks to see what parts need to be in place in order to have these animals be able to hit things. It turns out that there have been many times that life has found a way to hit things with a long part coming out of the bottom.

References:

 Arbour, Victoria M., and Lindsay E. Zanno. "The evolution of tail weaponization in amniotes." Proceedings of the Royal Society B: Biological Sciences 285.1871 (2018): 20172299. 

 Balthasar, Uwe, et al. "Brachiopod shell thickness links environment and evolution." Palaeontology (2019). 

Podcast 174 - Feeling Drained; Parasites in the Fossil Record

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The gang talks about two papers that look at potential examples of parasitism in the fossil record. One paper finds possible parasites attaching to ancient ostracods, and another paper details potential parasitic isopods on electric ray fossils. Meanwhile, James practices his spidey sense, Curt is suspicious that things are going too well, and Amanda’s internet has amazing timing.

Up-Goer Five (Amanda and James Edition):

 Today our friends talk about animals that eat other animals without killing them. First our friends talk about a paper that talks about an animal that has big teeth but no hard inside parts even though it is in a group that has hard inside parts and lives in the water. This animal has a number of smaller animals that have sort of hard outer parts, that may have been living on its skin by sticking its head inside its skin and living there. It is very hard to tell if this thing had its head in the animal with big teeth and no inside hard parts when it lived, or if it was just maybe eating the animal after it was dead. It is very hard to tell if things ate other things while they were still living or if they were there after it died.

Our friends also talk little animals that have five arms that today live in animals without legs that breath water. The animals with five arms first became animals with five arms that ate other animals without killing before the animals without legs that breath water came to be, so we did not know what the animals with five arms used to eat. Now we know that they would eat animals with lots of legs and a hard head, and that they would eat the animals with lots of legs and a hard head from lots of places, not just inside like they eat the animals with no legs that breath water.

References:

 Siveter, David J., et al. "A 425-million-year-old Silurian pentastomid parasitic on ostracods." Current Biology 25.12 (2015): 1632-1637. 

 Robin, Ninon, et al. "Eocene isopods on electric rays: tracking ancient biological interactions from a complex fossil record." Palaeontology 62.2 (2019): 287-303. 

Podcast 173 - Early Plants

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The gang discusses two papers that look into early plant evolution and ecology. The first paper looks at some evidence from fossil spores to determine where the earliest vascular plants on land may have evolved. The second paper looks at a unique Devonian forest ecology from China. Meanwhile, James accidentally hoists himself, Amanda is more heard than she thinks, Curt fails as acting like everything’s ok, and everyone has a good old time working around Amanda’s computer deciding to die.

Up-Goer Five (Curt Edition):

Our friends talk about old things that can make their own food from the sun. First, they talk about some of the oldest things that make their food from the sun which also have ways of moving water from the bottom of the thing to the top. Before this paper, it was thought that things which make their food and live on the land probably first started in the big piece of land that used to be made up of most of the other land pieces put together. With this paper, they found parts of these things which are used for making babies in the rocks of a different piece of land. This makes the people who wrote the paper think that, maybe, a lot of the changes in these early things on the land that make food may have actually happened in this other place.

The second paper looks at some very early trees. These trees are not the same as trees today, because they are not quite doing the same thing as trees today. But these early trees still act a bit like trees today. This paper finds a very interesting type of group of trees which seems to be in a place close to the big blue wet thing. This group of trees has the trees way more close together than we have seen before. It is a lot earlier than when we usually see trees that are grouped very close together. This means that trees got very close together with a lot of trees in one area very early on. This means that the big groups of trees we see a bit later on had their start earlier than we had first thought. This group of trees is also very cool is that the way the trees are grouped together is very different from what we see today, and even in the past. The trees are all the same type of tree and there are big, not so big but not so small, and small trees all grouped together. This means that lots of trees grouped together could really pull down some clear things in the air that control how hot the air is.

References:

 Wang, Deming, et al. "The Most Extensive Devonian Fossil Forest with Small Lycopsid Trees Bearing the Earliest Stigmarian Roots." Current Biology 29.16 (2019): 2604-2615. 

 Rubinstein, Claudia V., and Vivi Vajda. "Baltica cradle of early land plants? Oldest record of trilete spores and diverse cryptospore assemblages; evidence from Ordovician successions of Sweden." GFF (2019): 1-10. 

Podcast 172 - GSA 2019

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James, Brendan, Aly, Carlie, Anna, and Curt gather together at the 2019 Geological Society of America Meeting in Phoenix and discuss the various paleontology talks they saw at the event.

Day 1 (Anna, James, Curt, Brendan): 0:00 - 1:05

Day 2 (James, Aly, Carlie, Brendan, Curt): 1:05 - 2:37

Day 3 (James, Anna, Curt): 2:37 - 3:54

Day 4 (James, Carlie, Brendan): 3:54 - 5:17

Podcast 171 - Birds Get Swole in New Zealand

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The gang discusses some very interesting papers about bird fossils in New Zealand. These papers describe how many different types of birds ended up on New Zealand throughout the Cenozoic, and each time they experienced significant increases in their size. Sadly, since this was a very straightforward topic, no one could quite manage to focus on anything. So meanwhile, Curt remembers childhood animations that no one cares about, James makes it “fun” for himself and no one else, Amanda drinks the unholy combination of bourbon and rye (brye?), and everything just kind of gets way too 2019 near the end (EDITOR’S NOTE: Apologies for the inconsistent audio on this episode. The wrong inputs were used for some of the audio due to some last minute changes, but this should not happen in the future).

Up-Goer Five (Amanda Edition):

Today our friends talk about things with no teeth that can fly that can't actually fly and live on land that has water all around it. One of these things with no teeth that can fly but can't actually fly does sort of fly, but under the water instead of in the air. The other is a very large thing with no teeth that can fly but can't fly that people will have as an animal in their house a lot of the time. These things with no teeth that can fly that people keep in their house yell a lot and can also learn to talk. The one our friends talk about is just a leg, but it was very large and probably as big as a small child. The whole animal was that big, not the leg. The other thing with no teeth that can fly but can't fly but does sort of fly under the water is very big and very old and maybe is one of the oldest ones of these things with no teeth that can't fly anymore. It seems like maybe this land with water all around it was a good place for these early things with no teeth that can fly but now can't fly but sort of fly under water, because there are many of them there at this time. And they are very old, some of the oldest ones, and very big, so maybe being big is an old thing that this group of animals does.

References:

 Worthy, Trevor H., et al. "Evidence for a giant parrot from the Early Miocene of New Zealand." Biology letters 15.8 (2019): 20190467. 

 Mayr, Gerald, et al. "Leg bones of a new penguin species from the Waipara Greensand add to the diversity of very large-sized Sphenisciformes in the Paleocene of New Zealand." Alcheringa: An Australasian Journal of Palaeontology (2019): 1-18. 

Podcast 170 - The Impact of Taphonomy; On Conodonts and Dinosaur Nesting Sites

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The gang discusses two very different papers that are sort of united together based upon the importance of taphonomy. First, they look at a paper about how the ways in which conodont elements are preserved can affect our understanding of their evolution. Second, they talk about the recent finding of exceptionally preserved therizinosaur dinosaur nesting sites. Meanwhile, Amanda finds herself dealing with a failing webcam, Curt enjoys burying the lede, and James is never wrong unless he wants to be.

Up-Goer Five (Curt Edition):

Our friends talk about how the ways that things wear down can really change how we understand our past. First, they look at these things that are like teeth but are not and are part of this very old group of animals that are aunt or uncle to a lot of animals that have hard parts in their backs which live today. Some of these old animals that have not teeth have changes through time in their not teeth. The bottom of these not teeth appears to disappear in the animals we find which are closer to today. However, this paper finds new animals that show maybe the bottom of these teeth have not actually disappeared, but instead it turns out that this bottom part is very easy to break off. This is important because it means that the not teeth may still have some deep relationship to how actual teeth teeth form.

Next, our friends look at the places where big angry animals would lay bag like things that hold babies, here after we will call them sit places. A big question has been if these big angry animals liked to find sit places close to each other or far away. It is hard to tell this in the past because we can't always be sure all of the sit places were used at the same time. This paper find a single red line that runs across all of the sit places, which allows the people who wrote the paper to say that all of the sit places were probably used at the same time. Also, the number of babies that didn't die is a lot like the number of babies that don't die in animals who also find sit places together today. So it looks like these big angry animals probably shared sit places.

References:

Tanaka, Kohei, et al. "Exceptional preservation of a Late Cretaceous dinosaur nesting site from Mongolia reveals colonial nesting behavior in a non-avian theropod." Geology(2019). 

 Souquet, Louise, and Nicolas Goudemand. "Exceptional basal-body preservation in some Early Triassic conodont elements from Oman." Palaeogeography, Palaeoclimatology, Palaeoecology (2019). 

Podcast 169 - Learning about Agnostids

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The gang takes some time to discuss two papers about agnostids, a strange group of trilobite-like arthropods whose evolutionary history has been the subject of considerable debate. First, we discuss a short paper summarizing the history of the agnostid debate, and then we discuss a brand new paper using new material and Bayesian phylogenetics to offer a fresh new hypothesis. Also, James channels frustration into fun, Amanda nearly has her house destroyed by cats, and Curt asks the Star Wars questions no one wanted answered.

Up-Goer Five (Amanda Edition):

Today our friends talk about small animals that have no eyes that might be sisters of animals that live in the water that have three parts and big eyes, many legs, and can make themselves into a ball. The first paper talks about the small animals with no eyes and how hard it is to make one of these animals for people to look at. They talk about the past of the animal and where it lived, and who it might be close sisters to. They say that a very cool area where we find these animals lets us see the legs and that they are different, also that they have a different mouth, and that maybe they actually do have eyes but they are on the mouth? They are weird animals. The second paper also talks about these animals, but does not focus on making the animals for people to look at. It looks at these animals from a different very cool area and shows their legs are sort of like the legs of animals that live in the water that have three parts and big eyes, many legs, and can make themselves into a ball. The paper is different from others, though, because it says that these animals are really either part of or sister to animals that live in the water that have three parts and big eyes, many legs, and can make themselves into a ball. But that is the only part of the tree that really is strong, so maybe who knows still? Our cat friend is writing this and did not really know what was going on that day, and does not know much about these cool animals with maybe no eyes that might really be animals that live in the water that have three parts and big eyes, many legs, and can make themselves into a ball.

References:

Eriksson, Mats E., and Esben Horn. "Agnostus pisiformis—a half a billion-year old pea-shaped enigma." Earth-Science Reviews 173 (2017): 65-76. 

 Moysiuk, J., and J-B. Caron. "Burgess Shale fossils shed light on the agnostid problem." Proceedings of the Royal Society B286.1894 (2019): 20182314.

Podcast 168 - Alligator Teeth and Too Small Cats

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The gang discusses two papers that look at the diets of past and present crocodylomorphs using patterns in teeth shape and enamel. It turns out, past relatives of crocodiles were likely a lot more experimental in the types of feeding strategies they implemented than we might expect. Meanwhile, Curt comes up with a great name for a Lamsdell lab bowling league, Amanda loves possums, and James has some very strong opinions about the “Cats” trailer.

Up-Goer Five (Curt Edition):

The friends talk about two papers that look at the teeth of these big angry animals that hide and eat a lot of animals. It turns out that lots of these big angry animals are sons and daughters of older big angry animals which may have ate other things besides animals. These two papers look at the teeth of the living big angry animals and the older big angry animals to see what we can learn about what they may have ate. The first paper looks at the hardest bits that cover the teeth. In living big angry animals, they find that the teeth furthest back in the mouth have more hard parts covering them than the teeth near the front. This makes sense, because these teeth in the back hold on to animals and so need to be more covered. What they also find is that these big angry animals have way less hard parts covering their teeth than other other animals which are warm, but who do not grow new teeth every time they lose one. The hard parts are the same as some other big angry animals from the past, though some of the big angry animals that might have ate more than just animals have the parts where their teeth are hard being different.

The second paper looks at the ways the teeth look. There is a number that can be looked at which shows if the teeth are simple or if they are very different. Simple teeth usually means that the animal eats other animals. But the more different the teeth are, the more the animal may eat both animals and not animals, or just not eat animals at all. They use this number to study what past big angry animals would eat. What they find is that past big angry animals probably ate way more different things than we see today. While most big angry animals today eat only animals, it seems that not eating animals at all, or eating both animals and not animals, happened way more often in these past big angry animals. It means that maybe these big angry animals have been a lot more different in the past, and our living big angry animals are maybe more "weird" than we think.

References:

 Sellers, K. C., A. B. Schmiegelow, and C. M. Holliday. "The significance of enamel thickness in the teeth of Alligator mississippiensis and its diversity among crocodyliforms." Journal of Zoology

 Melstrom, Keegan M., and Randall B. Irmis. "Repeated Evolution of Herbivorous Crocodyliforms during the Age of Dinosaurs." Current Biology (2019). 

Podcast 167 - Jet Lagged Pterosaur Eggs

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[TRIGGER WARNER: Some dead baby jokes because we were in a very weird mental place, and also way too much rambling conversations about Star Wars]

The gang celebrates their cross continental trip to the 2019 North American Paleontology Convention by immediately getting on microphone the next day to talk about fossil Pterosaur eggs and what they can tell us about Pterosaur reproductive strategies. As expected, this may not have gone well. Witness the horror as barely conscious minds try and keep on topic for more than about 5 minutes! Apologies to the authors of these quite nice papers. [Editor’s note: The scientific discussion on this podcast “starts” around the 10 minute mark]

Up-Goer Five (Amanda Edition):

Today our friends talk about animals with skin arms. We are really talking about the baby animals with skin arms when they live in a small house with a hard outer part. One paper talks about the house of a baby animal with skin arms that is very round and good. You can see all the small bits of this house with a hard outer part. In fact, this house with a hard outer part is very much the same as some of the flying animals with no hair today. That might mean that these animals with skin arms were living like the flying animals with no hair that are around today. We already think they ate the same way, so now we think they might have lived and made their baby small houses in the same way too. The second paper is looking at baby animals with skin arms while they are still living in their house. Different parts of the inside hard pieces of these baby animals with skin arms get hard at different times as they get bigger, but they are still in their small house with a hard outer part, except that not all of the houses really have a hard outer part but that is a story for another time. Anyway some of the babies are still soft but some are very hard and that makes people think that maybe when these baby animals with skin arms come out of their small houses with either hard or soft outer parts they are able to leave the big home right away and go fly away. This is different than almost all living animals that fly and do not have hair except for one group which is big and strange and look kind of like the large big animals that fly (but these ones do not fly) that do not have hair and are good to eat and very stupid, but they do not are not part of that group. So these baby animals with skin arms are very different (maybe) than what is still living today.

References:

Unwin, David Michael, and D. Charles Deeming. "Prenatal development in pterosaurs and its implications for their postnatal locomotory ability." Proceedings of the Royal Society B 286.1904 (2019): 20190409. 

 Grellet-Tinner, Gerald, et al. "The first pterosaur 3-D egg: Implications for Pterodaustro guinazui nesting strategies, an Albian filter feeder pterosaur from central Argentina." Geoscience Frontiers5.6 (2014): 759-765. 

Podcast 166 - NAPC 2019

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We all just got back from the 2019 North American Paleontological Conference at UC Riverside with an extra long (over 5 hours) episode. Join James, Carlie, Curt, and Brendan as they discuss the talks they saw each day of the conference. Time stamps for each day: Day 2 talks ~ 54 min.; Day 4 talks ~2 hr, 36 min; Day 5 talks ~3 hr, 49 min.

Video versions of the discussion:

Podcast 165 - Sharks for St. Crispin's Day

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The gang have a “Shark Week” and discuss two papers about the ecology of modern tiger sharks. The first paper talks about a unique feeding strategy for some tiger sharks in which they can consume a fairly large amount of song birds. The second paper discusses how tiger shark populations are distributed around the islands of Hawaii, a place known for fairly high concentrations of tiger sharks. Meanwhile, James informs us of an important holiday, Curt imagines the ultimate battle of goose and shark, and Amanda decides to take charge of the podcast.

Up-Goer Five (Curt Edition):

Our friends talk about two papers that look at how these big animals with teeth that move through the water live. The first paper looks at what these big animals in the water are eating. People have been catching these big animals in the water and seeing what is inside of them. During some times in the year, usually the fall, these big animals in the water somehow eat a whole hell of a lot of these very small animals that talk a lot and move through the air. Turns out that most of the big animals in the water eating these small animals from the air that talk a lot are young but not babies. This shows a very interesting case where food comes from the land into the water. Often, food moves from the water into the land but this is the other way around.

The other paper looks at where these big animals live, focusing on a place where a lot of these big animals have had attacks with people. This paper showed that this one place seems to get a lot of these big animals because they like to make babies there. There is a lot of stuff this paper goes through, but the big important point is that this is a place where people play and move in water, and it is also important for these big animals, so this means that people and these big animals are going to come together at some point and the people should be told about this. Another cool thing is that the number of big animals in the area and the number of attacks are not the same, meaning that more of these big animals does not mean more attacks. It shows that making sure people know about these big animals is probably more important, and that scared attempts to kill these big animals do not make the problem better, and ends up very bad for the world.

References:

Meyer, Carl G., et al. "Habitat geography around Hawaii’s oceanic islands influences tiger shark (Galeocerdo cuvier) spatial behaviour and shark bite risk at ocean recreation sites." Scientific reports 8.1 (2018): 4945. 

 Drymon, J. M., et al. "Tiger sharks eat songbirds: scavenging a windfall of nutrients from the sky." Ecology

Podcast 164 - Rails and Snails

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The gang talks about two papers that are interested in iterative evolution, the repeated evolution of the same or similar morphological characteristics within or among species. Specifically, they are focused on iterative evolution in species on islands. The first paper they discuss looks at how being flightless might have evolved multiple times on the same island within the same species of rails. The second paper looks at repeated changes in developmental timing associated with climatic changes on an island. Also, James is an expert, Curt comes up with the best new Blue Sky series for the USA network “Rails and Snails”, and Amanda changes the podcast’s format.

Up-Goer Five (Curt Edition):

Our friends talks about two times that weird things happen when animals get on an piece of land that is surrounded on all sides by water. The first paper looks at small light flying things. When these flying things get onto a piece of land surrounded by water, they seem to stop flying. However, they find these remains of these light flying things on this one piece of land so they can see how the way these remains look change, because the way these remains look will tell us if these light flying things had decided to stop flying. The cool thing is that many different flying groups of this same flying thing landed on this pieces of land surrounded by water and all decided to stop flying on their own. So the story for these light flying things is that they land on this piece of land surrounded by water, they stop flying, and then they die from breathing water when the land goes under, and then when the land is above the water, they repeat.

The second paper looks at how these things that sit there, have a rock around them, and pull food out of water change over time. What the paper finds is that these little things with a rock around them look very different when the water goes up and down. The paper says that this is because of changes in how these little animals with a rock around them grow up. Do they take longer to grow up, do they look more like grown ups or do they look more like babies? The changes they see in how these things grow up happen at the same time as changes in where the water is, as well as how hot or cold it is.

References:

Hume, Julian P., and David Martill. "Repeated evolution of flightlessness in Dryolimnas rails (Aves: Rallidae) after extinction and recolonization on Aldabra." Zoological Journal of the Linnean Society (2019). 

 Hearty, Paul J., and Storrs L. Olson. "Environmental Stress and Iterative Paedomorphism in Shells of Poecilozonites (Gastropoda: Gastrodontidae) from Bermuda." Palaios 34.1 (2019): 32-42.