Peter’s Guppy Inheritance Science Fair Project tested to find out if a black male guppy and yellow/green female mated… would it result in black male and yellow/green female offspring.
The guppy (Poecilia reticulata) is a very popular freshwater fish for aquariums. The guppy can range in size from 2.5 to 6 centimeters long. The gestation period of a guppy is approximately 21-30 days long. The telltale sign of a pregnant female is a dark spot by its anus. It can take the female up to an hour to give birth to its brood of 5 to 30 fry (baby fish). After giving birth the female guppy is ready to be re-impregnated in around three hours. Fry take three months to acquire color. These facts make the guppy the perfect choice for my Biology Project.
I hypothesize that when a black male guppy and yellow/green female mate it will result in black male and yellow/green female offspring. Also when a orange male guppy and yellow/green female mate it will result in grey male and yellow/green female offspring.
- Buy four 20 long fish tanks and stands.
- Fill them with water to check for leaks.
- Empty tanks and fill them with an inch of gravel.
- Plant plants for baby guppies to hide in.
- Fill the tanks with water.
- Set up heater and filter systems.
- Buy two pair of identically colored female guppies.
- Buy two male guppies.
- Place a male in two tanks.
- Place the females in one tank and wait a month to make sure they aren’t pregnant.
- Put two females per one male in the tanks.
- Take pictures.
- Wait until all females are pregnant then remove the males and put them in the third tank.
- Wait two months for the females to give birth.
- Remove the females and place them in the third tank.
- Take pictures.
- Wait until all baby guppies are fully grown and develop body color.
- Record data and take pictures.
- Analysis results.
In addition it was noted that:
- In actuality I had started with 8 females and 4 males but 4 females and 2 males died.
- Since female guppies tend to be cannibalistic they may have eaten some of their young before being removed from the tank.
- Since the baby guppies are too small to count at birth some may have died during the period of growth before they were countable.
- Female guppies can retain sperm from previous mating and the males I breed them with may not be the fathers.
- At the time of writing this report only one group of babies is fully developed.
In conclusion my hypothesis was negated and supported by the data collected. In tank 5 I bred a black male with a yellow/green female. Their male offspring are all the same pattern of neon yellow/green with a broad midnight blue stripe. All the female offspring were a transparent green to yellow green. In tank 6 I bred an orange male with a yellow/green female. Their male offspring were all a dark blue with metallic red stripe on top. All the female offspring were yellow/green.
1. A Step by Step Book About Guppies by Jack C. Harris