My amazing fishy senses

Hi everyone! Thanks for coming back to my blog! Today I want to talk a little about fish sensory systems. Don’t worry, I’ll focus more in depth on each sense later!

Let’s see… where should I begin? Well did you know that I can see, hear, smell, and taste – just like you! My eyes work pretty similar to yours. Light is focused by a crystalline lens onto the retina. Like most fishes, I actually have really good color vision – that comes in handy when you’re really colorful like me. These bright colors can mean different things. My bright yellow coloring shows that I’m a dominant male defending a territory. Some of my friends are bright blue instead of yellow, but they’re also guarding a territory. Sometimes I have a dark bar across my eye. This is a sign of aggression, but sometimes it just means I’m stressed. I can also turn on and off a red patch on my body that I use during reproduction.

I can hear sounds too! Even though I don’t have an external ear that you can see, I have an inner ear that can detect sound vibrations (so please stop running those loud boats so close to my home!). I use sounds for a variety of things, but one of the most important is for courtship. I make this grunting noise during my mating dance – the ladies love it!

I can also taste and smell. The researchers also use the word ‘gustation’ for taste and ‘olfaction’ for the sense of smell, and these senses together are called ‘chemosensory’.  I have a nose, which is actually paired openings on either side of my head (or naris) that lead to my olfactory epithelium. Just like you, this olfactory epithelium has olfactory receptor neurons for detecting odorants. And I have taste buds not just inside my mouth, but on my lips and even on my body! These, along with solitary chemosensory cells, allow me to detect chemicals in the water I’m swimming in. It’s kind of like I’m a giant swimming tongue! These chemosensory cues help with identifying fish around me (if they’re a friend or enemy), food, predators, and other things I should either be attracted to or avoid.

I can also feel things. Not only do I have a somatosensory system that lets me feel touch, I also have a mechanosensory system called the lateral line. This allows me to feel water movements. It’s made of these little hairs like those found in the inner ear. They’re located in structures called neuromasts on the surface of my body or in little canals in my skin. So I can feel the water movements generated by fish that swim nearby. I can use this for schooling behaviors (aka hangin’ with my friends), finding food, or even social communication!

So as you can tell, I have some pretty nifty sensory structures, and they’re not that dissimilar from yours. The major difference is that mine function in water while yours are in air. I can use information detected from these different sensory systems for a variety of things, like finding food, avoiding danger, and even getting the ladies. Once detected, information is sent to my brain where it helps me figure out what the appropriate behavioral response is, like fight, flee, eat, or mate. After all, I don’t want to try to mate with some guy trying to steal my territory!

Stay tuned for the next post to learn more about how I use hearing and auditory communication.