The gang discusses two papers from a new locality of early fishes that give a lot of new insights into fish evolution. Meanwhile, Curt loves new Discord features, James shares some fun stories, and Amanda know how best/worst to keep everyone on track.

Up-Goer Five (Curt Edition):

Our friends look at two papers from a group of papers that just came out about a place where you can get really good parts from very very old things that live in the water and have hard parts on the inside and would be great great great great mom and dad to a lot of things that have hard parts inside and live on land. One paper looks at these animals that do not have a hard part in the place where they eat and looks at how they have really cool ways to move through water that gives us ideas about how these things that help move through water have changed over time. The other paper looks at a lot of different types of these animals that live in water and shows that they were doing a lot of different things very early on.

References:

Zhu, You-an, et al. "The oldest complete jawed vertebrates from the early Silurian of China." Nature 609.7929 (2022): 954-958.

Gai, Zhikun, et al. "Galeaspid anatomy and the origin of vertebrate paired appendages." Nature 609.7929 (2022): 959-963.

The gang discusses two papers that look at two papers that discuss the origin and evolution of a sessile filter feeding life habit. The first paper discusses how a new tommotiid fossil helps us better understand lophophorate evolution, and the second paper looks at the genetic pathways that barnacles and molluscs use to generate their shells. Meanwhile, James makes a sound, Amanda gets a surprise, and Curt shares totally real facts.

Up-Goer Five (Curt Edition):

Our friends look at how animals that make hard parts and do not do much moving around first started. The first looks at one type of animal that could be the start of one of these groups of animals that do not move much. These early animals are usually hard to find because they have parts that do not stick around for along time. However, this animal that was found had a lot of soft parts that showed what these animals would have looked like. It seems that these animals started out as being able to move a lot more, even though the animals that would come later would stop moving.

The second paper looks at two other groups of animals that make hard parts and do not move. It looks at how these animals make their hard parts. Even though these two groups are not close to each other, they both use a lot of the same ways of making their hard parts, with things that are not the same making sense because of how these animals need to stick to other things.

References:

Guo, Jin, et al. "A Cambrian tommotiid preserving soft tissues reveals the metameric ancestry of lophophorates." Current Biology (2022).

Yuan, Jianbo, et al. "Convergent  evolution of barnacles and molluscs sheds lights in origin and  diversification of calcareous shell and sessile lifestyle." Proceedings of the Royal Society B 289.1982 (2022): 20221535.