Guppy Genetics

Revision of 2020 Guppy Genetics Article

I revised my 2020 article ‘Guppy Breeding: Genetic Pitfalls and Successes‘.  Revision containsapril-18_2018-1 same basic material, but I simplified article.  I spent more time discussing popular mutations that can perplex beginners.  And I down-sized a complicated discussion on the genetics of swordtail guppies.   It was not that relevant in successfully outcrossing my beautiful delta-tail females (Photo) with male swordtail guppies.   These outcrosses were wildly successful and I had no trouble breeding out the swordtail trait.

Guppy Longevity

Older Female

Older Male

My latest article Guppy Longevity (39 pages and 97 scientific references) discusses the genetics of longevity and answers the question of why fancy guppies don’t live that long.   Article  delves into the many factors (inbreeding, outcrossing, heterosis, purging, outbreeding depression, evolution, and disease) that are associated with  longevity.  It puts much of the blame for guppy fragility onto the all too common practice of using only young adults as breeders.     I have tried to make the science understandable, educational, and interesting.   Photo shows a 15 month old male and female.   Still room for improvement, but this is progress.   (Two years ago, my guppies were dying of old age or “what-not” at 5-8 months.)

Small-Scale Guppy Breeding

How to breed nice guppies in just 8 planted tanks

I revised my 2018 article Small Scale Guppy Breeding on how I keep and breed fancy guppies in just eight planted tanks.  You won’t see anything about fish rooms, drilled tanks, automatic water changers, etc.  It explains how I overcame the modern guppy’s fragility and disease susceptibility.

Guppy Genetics 101

Genetics of breeding fancy guppies for fitness, disease resistance, and beauty


Breeding Guppies: Genetic Pitfalls and Successes (10 page article) describes my experiences with crossing various guppy strains–Metalheads, Blue Grass, pet shop guppies, swordtail guppies, etc.  Avoid the genetic problems I encountered as a beginning breeder.  Follow the story, which includes basic genetic explanations, to a happy ending–the creation of novel and beautiful phenotypes.  (Article revised June 2021)