47: Common Shiner

I write to you from Arapahoe, Ute, and Cheyenne land. I am interested in learning about the different animals that live in the place where I was born. I want to mention that biological classification as taught by western science has its roots in racism, sexism, and transphobia – here’s a good explainer about why.

I follow a twitter account called @YearonEarth which has been tweeting throughout 2020 as if it was the history of the planet compressed into a single year. Today, on December 3, 2020, we made it to Perderpes, the first terrestrial tetrapod, who lived 359–345 million years ago in the Carboniferous period. Prior to that, the account had been moving rapidly through the development of fish, culminating in lobe-finned fish Tiktaalik, who lived about 375 million years ago, and is homo sapiens’ first long dead ancestor to crawl up onto land and take a look around. Twitter’s response, naturally, has been to blame Tiktaalik for being the cause of all of humanity’s problems, notably, that since this guy crawled up onto dry land now I have to go to work. I say all this as a preamble to, I’ve been thinking about fish a lot lately.

Today’s animal is the Common Shiner (Luxilus cornutus), a freshwater fish found across eastern and central North America.

In Colorado, they live in isolated locations, notably in the northeastern and north central part of the state around the St. Vrain and Poudre rivers. They are native to the South Platte. They actually prefer a type of habitat that is not really found in Colorado, notably, shaded, gravel-bottomed waterways. In Colorado most streams are silty and sediment-filled rather than gravel-bottomed. During mating season, males are territorial, and will actually move a few pieces of gravel around to create a nicer spawning site. They are vegetarian in the spring and carnivorous in the summer and winter.

They’re not threatened, and they are part of the Cyprinidae family that includes carps and minnows, the largest and most diverse fish family, not to mention the largest vertebrate animal family – containing over 3000 species, of which 1270 are still living today. Think about a fish – stop thinking about Finding Nemo, this is a freshwater fish – just the most generic fish you can think of – and I bet you are picturing something like the Common Shiner.

Fish are defined as gill-bearing animals whose limbs lack digits, and the Common Shiner definitely fulfils that. But fish are also our distant ancestors, a type of life that has been going strong on planet Earth much longer than any life that looks like ours – and for that matter, that dominates an ecosystem much, much larger than ours. I was trying to think of something interesting to say about the Common Shiner but really, what could be more interesting than contemplating the vast temporal and geographical dominion of the Fish?