Palaeo After Dark

The gang discusses two papers that look at the ecology of the ancient shark Megalodon. One paper uses our knowledge of modern sharks to fill in the missing data on what Megalodon could have looked like, and the other looks for evidence of Megalodon nurseries in the fossil record. Meanwhile, Amanda cares too much, James spreads “facts”, and Curt would really like to find a segue.

 

Up-Goer Five (Curt Edition):

Our friends talk about two papers that are about a really big angry animal with large teeth that moved through the water and is known by a lot of people. This animal with big teeth lived a long time ago and would have eaten other really big animals. But because most of this animal is made of soft parts, we do not know a lot about what it would have looked like. So the first paper uses other animals which are very close to this big animal (but not as big) and see how they all look to see if bigger things look the same. They find that they can guess what parts of these animals should look like just by looking at their teeth, which is cool! They then use this to guess what this really big old animal could have looked like.

The second paper looks at how these big animals would have raised their babies. Some places where we get teeth from these big animals do not have a lot of big teeth, while other places do not have a lot of small teeth. This paper looks at these places to see if the change in how big the teeth are is important. They find that some areas really do have more small than big teeth. Some areas also have more teeth that are between being big or small. It seems that smaller animals (babies) lived in some areas, and then when they get bigger they move out.

 

References:

Herraiz, Jose L., et al. "Use of nursery areas by the extinct megatooth shark Otodus megalodon (Chondrichthyes: Lamniformes)." Biology letters 16.11 (2020): 20200746.

Cooper, Jack A., et al. "Body dimensions of the extinct giant shark Otodus megalodon: a 2D reconstruction." Scientific reports 10.1 (2020): 1-9.

Direct download: Podcast_210_-_Mega_Shark_Doot_Do_Do_Do.mp3
Category:general -- posted at: 3:00am EST

The gang discusses two papers that look at how animals take up space in a community. The first paper looks at ancient reef systems and uses spatial analysis to infer ecological interactions between corals. The second paper looks at the impact that lions have on other predators in South African reserves. Meanwhile, Amanda loves a number, James is an adult, and Curt has some strange ideas about pizza.

 

Up-Goer Five (Amanda Edition):

Today our friends talk about space. Not the cool space, with stars, but the space between animals. The first paper looks at tiny animals that form big groups that look like rocks. There are two kinds of tiny animals that formed big groups that look like rocks from a long time ago. In the first paper, it turns out that some of the tiny animals that formed big groups that look like rocks settle in a space and then make it better for other types of tiny animals that formed big groups that look like rocks. Sometimes we would think that these animals would fight and would not want to help each other, but it turns out that actually they might really need each other to live in a place. This paper uses new ways of doing things, so their stuff is really cool, but is also really new; it's never been done on tiny animals that formed big groups that look like rocks before, only on big tall green trees. So more stuff needs to be done with this new way of doing things. The second paper looks at large animals where boys have lots of hair around their heads and necks and the girls do all the work. The short of it is that when these large animals where boys have lots of hair around their heads are around, there aren't as many smaller things that eat other animals. But there seem to be more kinds of smaller things that eat other animals when large animals where boys have lots of hair around their heads and necks are around. So it is kind of weird.

 

References:

Dhungana, Alavya, and Emily Mitchell. "Facilitating corals in an early Silurian deep-water assemblage." (2020).

Curveira-Santos, Gonçalo, et al. "Mesocarnivore community structuring in the presence of Africa's apex predator." Proceedings of the Royal Society B 288.1946 (2021): 20202379.

Direct download: Podcast_209_-_Spacing_Out.mp3
Category:general -- posted at: 3:00am EST

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