Quantifying muscle anatomy in elongate fishes

One of the best parts of working in the Tytell lab is that you will always be surrounded by kind, curious, and supportive people. The lab environment is perfect for individuals who want to practice thinking critically, are willing to learn new techniques and software, and want to have fun while doing cool science! The lab integrates approaches from several different disciplines including but not limited to: physiology, biomechanics, neurobiology, functional morphology, fluid dynamics, and engineering. We mostly answer questions about fish swimming, and we study fish swimming at multiple levels: inside of the fish (muscles, bones, sensory systems), the whole fish (fin and body kinematics), and the interaction of the fluid and the fish (fluid dynamics). We even use models such as flapping foils, soft robotics, or computer simulations to answer questions about fish swimming! 

Studying fish swimming is important for many reasons! Overall, fishes are great models for understanding evolutionary patterns as they are the most diverse vertebrates on the planet. We can assess how differences in muscles and muscle use, sensory systems, skeletal anatomy, body and fin shape, or behavior impact swimming performance, and why that matters for different groups of fishes. From an ecological standpoint, understanding how fishes swim sense their environment may tell us more about why they inhabit certain environments over others. It also allows us to predict how their dispersal may be affected by climate change and human-induced changes to their environments which has implications for conservation of ecologically and economically important species. Fishes are also common sources of bioinspiration for engineers aiming to improve the efficiency and maneuverability of autonomous underwater vehicles. Current designs of AUVs are far less efficient than fishes, so a better understanding of fish sensory systems and motor control is critical to inspire better technology. 

Some recent and ongoing research in the lab includes: 

• Understanding the role of the fins and body during turning, deceleration, and acceleration.
• Investigating caudal fin use during vertical swimming.
• Testing the use of vertical optomotor responses in fishes to induce vertical swimming.
• Understanding the role of vision and the lateral line in schooling behavior of different species of tropical fishes.
• Describing lateral line morphology in schooling fishes.
• Describing the skeletal and muscular morphology of the caudal fins in elongate fishes.
• Understanding the role of the caudal fin shape on passive bending and thrust generation of elongate foils.
• Investigating how the flexibility of fish bodies influences swimming performance. 

The proposed summer project is to study functional role of the caudal fin (the tail) in fishes, particularly in elongate (eel-like) fishes. Nearly all fishes have tails, and for many fishes, the tail plays an important role in steady swimming and unsteady maneuvers such as turning. In elongate fishes, the role of the tail during swimming and its anatomy is not well-understood as most fins are small and therefore commonly understudied. We will use representatives from a group of elongate fishes that live in different habitats in the Pacific North-west to compare muscle presence, shape, and attachment to predict active vs passive use of the tail during swimming.