Silverados

I have been busy in the past couple of months getting out new books in paper and e-book format. No sooner did I get that done when Bill Gill asked for some help on the IGEES.ORG site. I ended up taking back the URL and the hosting for the site and rebuilding it, and producing yet more documents!

Today I finally finished with that and was able to get back to my fish room, camera in hand. 

My latest generation of Magentas have segregated into some new variations, like this Silverado.

Silverado

A silverado is a Moscow with the Mg (Metallic gold) gene and the magenta gene. This makes it different from a Flamenco Dancer, which is essentially a Moscow with the magenta gene, but NOT the Mg gene. 

I really like Silverados. The Magenta gene turns them into short-tailed guppies. I like the thick peduncle in combination with the short fins. I also like the mottled nature of the mutation. As a result of my microscope work, I know why the guppy has a mottled look. It is because the magenta gene turns yellow color cells into red color cells. The following picture shows this exactly.

Sibling of the Silverado

Notice that wherever you see yellow on the sibling you see red on the Silverado. Look at the base of the peduncle and the caudal fin of the sibling. There you see the typical expression of the Mg gene. It is yellow. The other thing you notice is that the fins are not short tail. They are full delta. 

What is particularly interesting is the shape of the dorsal fin on the Silverado. Why is it a long, rounded rectangle, rather then a ballooning sail like his brother?

Presumably the Magenta gene suppresses fin elongation. So the short tail version is the "default" or wild type fin shape.  This is very interesting because it means European short tail guppies are implicit in the delta tail (called triangle tail in Europe). Remove the fin elongating genes and you get a short tail. There are no special short tail genes...except the gene suppressing fin elongation. Once again the story of guppy color and fin genetics has to do with gene regulation...the regulation of one gene by another. 

I am not absolutely sure if the magenta causes elongation to fail because of its effect on yellow color cells. Perhaps the Magenta gene affects iridophores as well. But the two brothers in the picture above strongly suggest that it is the suppression of yellow color cells. Perhaps yellow color cells are the key to fin elongation. What you you think?