Sun, 24 April 2022
The gang discusses two papers which discuss the fascinating information which can be gleaned from studying fossil trackways, particularly the taphonomy of fossil trackways. The first paper looks at how enigmatic elongate tracks may have formed, and the second paper uses tracks to infer paleo topology. Meanwhile, James is a latchkey kid, Amanda opens up the wrong folder, and Curt would like you to know that the joke is over now.
Up-Goer Five (Amanda Edition): Today our friends look at two papers that talk about foot marks. The first paper is looking at how the foot marks might get long. The ones made by big angry animals with big teeth and no hair are not supposed to be long in the back, but sometimes they are. This paper asks why they are. These big angry animals with big teeth and no hair usually walk on only the very front of their feet. Sometimes papers say it's because the whole foot is put on the ground. But this paper says that it is not because of that but instead that the whole foot goes deep into the ground. This makes the foot mark look very much longer than it should be. The second paper looks at how some big angry animals with big teeth and no hair walked along a place where the ground was not together and not straight. These animals were walking up and down along this not-straight ground. The tracks they left were not good but they can tell us how things did stuff and walked around and moved on the ground. It just shows that even bad tracks can tell us lots of good things.
References: Xing, Lida, et al. "Unusual dinosaur trackway preservation as clues to paleo-landscape and behavior from the Lower Cretaceous Luohe Formation, Shaanxi Province, China." Geoscience Frontiers 12.2 (2021): 737-745. Lallensack, Jens N., James O. Farlow, and Peter L. Falkingham. "A new solution to an old riddle: elongate dinosaur tracks explained as deep penetration of the foot, not plantigrade locomotion." Palaeontology 65.1 (2022): e12584. |
Sun, 10 April 2022
The gang discusses two sets of papers about how we study crocodylomorphs, with each of these topics being replies to previous studies. The first paper looks at the importance of total evidence approaches in determining the evolutionary placement of fossil pseudosuchians, and the second set of papers discusses the potential biases and issues associated with how we handle body size data in evolutionary studies. Meanwhile, Curt goes Camus, Amanda has some bizarre funeral plans, and James continues to have opinions about pies.
Up-Goer Five (Curt Edition): Our friends look at a lot of papers that were written to reply to another paper. All of these papers look at how we study big angry animals that spend a lot of time in water and jump out to eat things. This group of animals has been around for a long time and before today they used to do a lot of different things, even though now most of them spend a lot of time in water and jump out to eat things. These papers look at the older groups of these animals. The first paper looks at how we try and understand how these older groups go together. It shows that if you only look at how these things look, there are a lot of different ways these groups could go together. They say that things get better if we use both how they look and the changes in the small stuff that helps build up all life. This is important, because how these old groups go together will change how and when we think the groups of big angry animals we see today first came to be. The second group of papers looks at how big these angry animals were in the past. One of these papers looked at how big these animals got over time, but the reply shows that there are some problems with how that was done. If you just take how big these animals are without doing anything to those numbers, it means that something that is big getting slightly bigger is going to seem like more than something small getting bigger about the same. It is because the bigger thing starts with bigger numbers. You can fix this by doing some things to the numbers to make sure that you can better look at changes in both small and big animals. When you do that, it does change the story of the paper.
References: Darlim, Gustavo, et al. "The impact of molecular data on the phylogenetic position of the putative oldest crown crocodilian and the age of the clade." Biology Letters 18.2 (2022): 20210603. Stockdale, Maximilian T., and Michael J. Benton. "Environmental drivers of body size evolution in crocodile-line archosaurs." Communications biology 4.1 (2021): 1-11. Benson, Roger BJ, et al. "Reconstructed evolutionary patterns for crocodile-line archosaurs demonstrate impact of failure to log-transform body size data." Communications Biology 5.1 (2022): 1-4. Stockdale, Maximilian T., and Michael J. Benton. "Reply to:‘Reconstructed evolutionary patterns from crocodile-line archosaurs demonstrate the impact of failure to log-transform body size data’." Communications biology 5.1 (2022): 1-4. |