selective breeding

I made a little dolicho-brachycephalic flip-book animation for Kat:

Wolf-dog:               100,000 BCE
Spitz-type dog:         10,000 BCE
Bulldogge:                   1800 CE
Boston Terrier:            1960 CE

Happy animal husbandry day!

I basically just did a Boston Terrier drawing, then a wolf drawing, and then in-betweened them, so they’re not quite accurate in terms of timeline, but it’s a rough estimate

Today, thanks to this photo by Stephen Ausmus, we learned that carrots now come in nearly every color of the rainbow. We think that’s pretty awesome. This root vegetable rainbow is the result of a selective breeding program by researchers at the USDA’s Agricultural Research Service. Domestic carrots have been selectively bred over the centuries in order to improve their taste, texture and size, but we had no idea that so many different color varieties exist.

[via Twisted Sifter]


Morphs of Tiger (Panthera tigris)

  1. A snow, normal, golden tabby or strawberry, and white tiger lined up for a good comparison of the range of color. [x]
  2. A wild abundistic or pseudo melanistic tiger, with thicker and denser stripes than average. [x]
  3. A very strange and frankly exciting animal to me, a white abundistic tiger. The narrow stripes become very dense on it’s forehead and back half of it’s body, looking nearly solid in places, especially along it’s back and tail. Here is an article with a picture of this animal when it was a cub. [x]
  4. This beautiful golden tabby has dark orange stripes rather than black ones, and this color morph is associated with a softer coat.
  5. Not as extreme, this female golden tabby does retain dark stripes on her head and legs. Though probably due to the camera quality, she does seem to have a duller tan base color. [x]
  6. At first glance this white tiger appears to simply be dirty, and while it is a little scruffy, the areas with the light tan does look to be in the areas it would be in most “normal” tigers.[x]
  7. A white tiger, with orange remaining between it’s eyes. [x]
  8. This snow white tiger has stripes that are mostly light, the darkest on the head and limbs, the rest faintly visible. [x]
  9. A grumpy snow, it seems to have a bit more color in it’s coat, with pinkish tan stripes and muzzle. Here is the same cat.[x]
  10. Because of the high amount of inbreeding it takes to make white tigers, animals like Kenny are sometimes produced, but rarely displayed. His face is pug nosed, with misshapened teeth. Most don’t appear this extreme, but many do have serious underlying health issues, with cross eyes seeming to be the most common ailment. Reputable zoos or breeding programs interested in conservation will not intentionally produce tigers of any morph, and instead focus on breeding and maintaining subspecies purity. [x]

Part two on subspecies here.

Britney Spears invented dogs in 2002 through a process now referred to as “selective breeding”. She began in 1996 when she bred her two short-haired guinea pigs, Coco and Buddy. Year after year, Spears would breed the largest and most distinctive guinea pigs from each litter and eventually broke the world record for the largest guinea pig (Jimbo, 6.2 kg, 1999). Over the course of 6 years and 8 generations, a significant genetic mutation occurred and the first dog (Bit Bit) was born. Spears continues to breed dogs to this day and produces beloved pets for families all around the world.


Columbia livia domestica - Domestic pigeons

Think the breeding of show animals is exclusive to dogs and horses? No way. My eyes have been opened to the intensely competitive and diverse world of domestic pigeon keeping. Domestic pigeons (Columbia livia domestica) are derived from the rock dove (Columbia livia), similar to how domestic dogs (Canis lupus familiaris) are a subspecies of the grey wolf (Canis lupus). There are three different features or characteristics pigeons are selectively bred for: utility, fanciness, or flying. These traits aren’t so unlike the different characteristics for which dogs are bred (except for the flying part [maybe]). 

  • Kite Saddle Fantail - Fancy show breed; fantails have 2x-3x as many tail feathers as your average rock dove. 
  • Black English carrier: Fancy show breed, no longer used for message delivery.
  • Red Jacobin - The jacobins are able to hide the head entirely in a muff of feathers, which is raised and lowered at will. 
  • Blue barred spot swallow - The swallows are usually bred with the feathered toes known as “muffs" 

I half expect that jacobin to be wearing a monocle underneath its fancy collar. 

All of these beautiful examples were donated by breeders from the Chicago Pigeon Club.

From the "Results of Artificial Selection in Domestic Pigeons” case at The Field Museum.


Axolotl (Ambystoma mexicanum)

  1. A gorgeous dark grey wild type, the speckling and colors of wild types can vary greatly from animal to animal, enough to warrant a separate post later on. [x]
  2. This melanoid is a velvety black animal with blue-grey undersides, it has none of the iridescence (iridophores) found in most other morphs. [x]
  3. Unfortunately, this unique copper never made it to adulthood. Like all coppers, it lacks black coloration. This variety does come in many shades, and I find this one’s light yellow base with golden flecks particularly stunning, along with the fact that it is also possibly piebald. The light and translucent skin around it’s limbs and neck probably would have become more solid with age, though we’ll never know. [x]
  4. A trio of morphs. The bright yellow hued golden albino, what looks like two melanophore (black pigment) and xanthophore (yellowish pigment) deficient white albinos, and the ever popular pink gilled and darked eyed leucistic that most people are familiar with.[x]
  5. Leucistic axolotls can have black markings, this particular one has a solid black mask and freckled back. [x]
  6. Half wild type and have leucistic, this chimera is a flashy whoopsie made by two embryos fusing into one animal early on in it’s development. [x]
  7. I can’t find much info on this gorgeous enigma. It seems to have characteristics of the melanoids in it’s dark base color, with patches of golden flakes standing out against it. The gills are pink, and the undersides appear to be a translucent white.[x]
  8. A wild type axolotl with the eyeless mutation, this trait is said to render the animal sterile. [x]
  9. My personal favorite, an eyeless animal with an unknown skin mutation. The skin is a shade of orange-red I’ve never seen in other examples, with thick looking patches of white that appear to be some sort of fungus, though is just a strange build up of pigmentation. [x]
  10. Normally neotenous and able to reproduce in it’s larval looking stage, axolotls will rarely metamorph into the terrestrial “adult” form naturally like this one. They are built very much like the other mole salamanders in their genus. You can force the change by using hormones, though by all accounts it cuts the lifespan much shorter and is considered cruel to do. Here are a few examples of different varieties artificially morphed.[x]

So the Pug from 1880 is a Pug they caught in the wild or what?

 Behold the rare Canis Pugaris, untouched by humanity until 1880 when brave Victorian men went on the hunt for these mysterious canines in the forests of China! Come and see this vicious beasts from the orient! You won’t believe your eyes! This creature is brought to you straight from the Asian wilderness where it devoured the wildlife and even the Chinese with its horrifying underbite!

Bitch please…


Egg color in domestic chickens (Gallus gallus domesticus)

  1. A color wheel of the different hues chickens can produce. All egg shells start off as while before they pass through the oviduct. Browns are caused by pigmentation called porphyrins that is added towards the end of the laying process, and the amount of porphyrins differs from breed to breed. The blue coloration is made during an earlier stage,  is created by oocyanin from the bile. Since blue is added earlier, the inside of a blue egg will be blue, compared to the white inside this brown egg [x]
  2. Leghorn: white [x]
  3. Plymouth rocks: light pinkish [x]
  4. Buff orpingtons: light tan [x]
  5. Cochin: brown, similar to light terracotta [x]
  6. Welsummer: brown and usually speckled [x]
  7. Maran: deep, chocolate brown. One speckled from a cuckoo maran, the lightest from another brown layer for comparison. [x]
  8. Araucana: light blue [x]
  9. Easter eggers (araucana crossed with a brown layer): shades of pink, blue, light minty green, light mossy green [x]
  10. Olive eggers (araucana crosses with dark brown layers): olive green [x]

Happy Easter (or happy Sunday)!


Varieties of Tortiseshell Cat (Felis silvestris catus)

This is a really huge set, since I didn’t feel like splitting it up, so I’m not going to be as wordy as usual. Also forgive my crap fake photoset lines.

  1. Tortoiseshell is a sex linked coat of black and orange blended together usually female cats carry, though tortie males with Klinefelter syndrome (XXY rather than XY) pop up rarely. Tortoiseshell & white has some amounts of white in the coat, and the markings can be a little more solid. Calico is a tortie with higher amounts of white, and the three colors in the coat tend to have well defined borders, like patchwork. Side note, his term is mostly used in the US. [x][x][x]
  2. Blue (dilute black) : tortie, calico Scottish fold, van munchkin [x][x][x]
  3. Chocolate: tortie American curl, tortie & white ragdoll, calico oriental [x][x][x]
  4. Lilac (dilute chocolate): tortie British shorthair, calico ragdoll, tortie point Birman [x][x][x]
  5. Cinnamon: tortie , tortie & white, and van British shorthairs [x][x][x]
  6. Fawn (dilute cinnamon):calico and calico van British shorthairs [x]
  7. Torbie is the combination of tortie and any of the tabby patterns. Ticked, classic, mackerel, spotted. [x][x][x][x]

“Gradually, by selective breeding, the congenital differences between rulers
and ruled will increase until they become almost different species. A revolt of the plebs would become as unthinkable as an organized insurrection of
sheep against the practice of eating mutton.”
*- Bertrand Russell, “The Impact of Science on Society”, 1953, pg 49-50*