 spotting form and the mottled spotting form is the amount of white. The variegated spotting is an extended form of mottling. There is more white on the back and rump, allowing less color to show through. This can form a 'dalmatian' pattern. Often the tail tuft and the end of the tail is white or lacking pigment.
- Extreme White - The extreme white pattern is associated with any standard color except for white. Here the coat color is 90% white and barely any of the base coat color, or any pigment, is remaining. There have been health concerns circulating about extreme white gerbils. Head tilts, lack of good balance, and repetitive running and circling has been reported in these gerbils. It has been found that these health concerns mostly affect gerbils with unpigmented (light pink/not very opaque) ears.
There are other spotting "types". Any that don't conform to show standards are usually classed as patched.
Note: Although some US gerbil owners call some coat varieties "fox" i.e. yellow fox, the fox gene is not in gerbils and this is therefore incorrect.
Though not much is known about breeding in wild Mongolian gerbils, we know that they can have as many as 18 pups, compared to pet gerbils which can only have 14. The families make sure all young females in their groups leave before that can fall pregnant and kill the mothers' newer pups whilst still in the family unit. The father or older brothers will mate with younger females. These young females have the ability to carry sperm for up to 2 weeks until they are sexually mature (at 3-4 months) so that they can make a family of their own without the interference of another male who may kill the fathers pups. This is why it isn't recommended to keep an older male gerbil with a younger female as a cage mate for a prolonged amount of time.
- N. Batsaikhan & K. Tsytsulina (2008). "Meriones unguiculatus". IUCN Red List of Threatened Species. Version 2011.2. International Union for Conservation of Nature. Retrieved January 26, 2012.
- Schwentker, V. "The Gerbil. A new laboratory animal." Ill Vet 6: 5–9, 1963.
- Hazardous Substances and New Organisms Act 2003 - Schedule 2 Prohibited new organisms, New Zealand Government, retrieved 26 January 2012
- Schwentker, V. "The Gerbil. A new laboratory animal." Ill Vet 6: 5–9, 1963.
- American Gerbil Society Color Strips