4. The keel lateral line canal (pink color) is quite strange: neuromasts are surrounded by modified scales (shown in blue), and keels have an odd set of elongated skeletal elements posteriorly. Tuna keels are clearly mechanosensory.

3. Now, a team led by @juliachaumel.bsky.social and published in iScience @cp-iscience.bsky.social shows that tuna keels have a sensory function too! Each keel has a peculiar lateral line canal with small tubules that extend to the upper and lower keel surfaces (www.cell.com/iscience/ful...

2. And here’s a view of the caudal fin and keels from behind during #tuna locomotion. Our previous work has shown that the keels decrease power requirements during swimming, likely by reducing lateral forces and yaw torques. But wait, there's more!

1. #Tuna have well-developed bilateral keels extending to the right and left sides at the caudal peduncle area just in front of the tail. This movie shows the keel area during locomotion in yellowfin tuna. What is the function of keels in #tuna? A🧵 and new hypothesis.

We propose that the ray tail acts like a “hydrodynamic antenna” providing detailed information to the ray on water movement behind the body. This video shows the effect of moving water near the tail of a cownose ray as it passes by.

There are paired lateral line canals along both sides of the entire length of the tail with a remarkable branched structure that ends at the tail surface with clusters of pores. Each canal has a continuous neuromast that extends the entire tail length!

What is the significance of the tremendous diversity of #shark skin #denticles? Presenting our experimental approach to understanding this at the Atlanta #SICB2025 meetings. Come to the session for all things shark skin!

Why do #fish swim in #schools? A🧵and new hypothesis. Schooling could help fish avoid predators, navigate, communicate, find mates and food, and save energy. Here we propose and test a new hypothesis: https://tinyurl.com/yc764d74

Do #fish swimming in a #school actually save energy? A🧵on this as our paper in @eLife https://elifesciences.org/articles/90352 by @TheYangfanZHANG addresses this question. This is a challenging issue to study: energy use by a school should be compared to solitary locomotion

We showed that fish tune their tail beat to the foil, intercept vortices, slightly alter body motion, and tune phase based on their distance from the foil. Due to how the head intercepts the foil wake we propose that fish can reduce swimming costs even in a thrust wake.

@rthandiackal and I conducted experiments to simplify the in-line swimming condition and allow a fish to swim in a thrust wake generated by a flapping foil (the @eLife link makes it easy to see the videos embedded into the main text): https://elifesciences.org/articles/81392