Palaeo After Dark

The gang discusses two papers that look at how trace fossils can give important clues to ancient ecological interactions. The first paper identifies a unique behavior using trace fossils, and the second paper uses bite marks on bone to infer ontogenetic ecological shifts in a large caiman species. Meanwhile, Curt investigates, Amanda collects, and James fixates.

 

Up-Goer Five (Amanda Edition):

This week our friends talk about animals that roll in wet tiny pieces of rock that are really very tiny tiny. We also talk about a very big very slow animal with hair that got bit by a very large animal with no hair but hard skin and lots of big teeth that has a very long face. The animal with hair that rolled in wet tiny very very tiny pieces of rock shows that these animals did this thing a very long time ago; it shows that these animals with hair and two fingers on each leg were in this place at this time, along with animals with stuff that wasn't hair but made of the same stuff as hair and could fly, too. The second paper looks at how we can talk about a hard part of a very big very slow animal with hair could have gotten grabbed by a small one of a very, very, very big animal with no hair but hard skin and lots of big teeth with a very long face. It tells us that these very big animals with no hair but hard skin and lots of big teeth ate different things when they were small than when they were very, very, very big.

 

References:

Abbassi, Nasrollah, et al. "Vertebrate  footprints and a mammal mud-bath trace fossil (Laspichnia) from the  Mukdadiya Formation (Late Miocene–Pliocene), Chamchamal Area, Kurdistan  Region, Northeast Iraq." Ichnos 28.1 (2021): 72-83.

Pujos, François, and Rodolfo  Salas-Gismondi. "Predation of the giant Miocene caiman Purussaurus on a  mylodontid ground sloth in the wetlands of proto-Amazonia." Biology Letters 16.8 (2020): 20200239.

Direct download: Podcast_225_-_Columbo_Meets_the_Caiman.mp3
Category:general -- posted at: 3:00am EST

Random computer glitches are unable to stop the gang from delivering another podcast! This week, they focus on two papers that look at the importance history for understanding trends in our modern biosphere. The first paper discusses how speciation trends are important for planning future conservation efforts, and the second paper looks at the importance of exaptive traits (characters evolved for one purpose but used for another) in the evolutionary history of sea snakes. Meanwhile, Amanda cuts deep, Curt has done this before, and James waits for his time to tell his very good joke.

 

Up-Goer Five (Curt Edition):

Our friends talk about how the past is important. And this is funny because they already did this before but the big boxes with bits that will shock your hand if you touch them lost the talk they did about the past being important so they are doing it again. The first paper they look at is short. It is about how animals living in places that are high up but in warm places make new types of animals that stay at the same high up place, not higher or lower. This means new animals will more often be living the same types of places as the older animals they came from, and this means that as places change we need to make sure the types of places where these animals live can stay open.

The second paper looks at how long animals without legs moved into the water. There are many groups of animals without legs that moved into water, and this paper wants to know the types of places they were in before they moved into water and also if the things they all have that make it easier to be in water were things that appeared before they moved into water (letting them move in there) or after they moved into water (making it better to be in water). They find that most of these groups started in areas with trees before moving into water. They also find that the things which make it easier to be in water appeared in older groups well before these animals moved into water. This means that the things that made it easy to go in water appeared first, and then this made it so these animals could then move into water.

 

References:

Linck, Ethan B., et al. "Evolutionary conservatism will limit responses to climate change in the tropics." Biology Letters 17.10 (2021): 20210363.

Gearty, William, Elsie Carrillo, and  Jonathan L. Payne. "Ecological filtering and exaptation in the evolution  of marine snakes." The American Naturalist 198.4 (2021): 506-521.

Direct download: Podcast_224_-_Second_Times_the_Charm.mp3
Category:general -- posted at: 2:00am EST

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