Sex and the Single Guppy Simulation

1. If being flashy and colorful attracts predators, why do you think guppies are so colorful?
Being flashy and colorful also helps the guppies attract mates, so if they can survive while being colorful, the guppies will mate and pass on those survival traits.


2. After viewing the guppy gallery, pick the fish you find most interesting. What is the fish’s scientific name, origin and average size? Describe the coloration of the fish you chose.

I particularly liked the poecilia reticulata, a 1.4" male from Brazil. It's a very interesting combination of colors, including black, yellow, green, white, and red. The colors are splotched throughout the fish.

3. After viewing the predator gallery, pick the fish you find most interesting. What is the fish’s common name, scientific name, and origin?

I liked the fat sleeper, also known as dormitator maculatus, from Southern North America, Bahamas, and Latin America.

4. View the guppy’s habitats, what habitat conditions would affect the predator populations?

Shallow pools would be very hard for predators to get into, and the only ones that would make it there would be weak predators. Small dams prevent many predators from going upstream, and large dams stop almost all predators. A section of a stream, however, allows both guppies and predators to move freely. Finally, small trickling streams could prevent larger predators from moving in.

5. Who is John Endler? What did he study and where did he study it?
John Endler was an evolutionary biologist who studied wild guppies in Trinidad streams.

6. For each of the three stream areas, describe the guppy coloration:

Pool 1: Many spots, bright, multi-colored

Pool 2: Medium spots, medium coloring

Pool 3: Drab colors, few spots, spots concentrated around tail


7. Develop your own hypothesis about guppy coloration. The hypothesis should answer the questions: Why do guppies in different areas of the stream have difference in coloration? (You can choose from the list on the simulation, or make up your own)

Guppies in different areas of the stream have different coloration because their different numbers or kinds of predators influences their coloring differently.

Trial 1
Guppy: Mostly Bright
Predators: 30 Rivulus, 30 Acara, 30 Cichlid

0% of Brightest Guppies (10 generations)
2% of Bright Guppies(10 generations)
4% of Drab Guppies(10 generations)
94% of Drabbest Guppies(10 generations)

FROM CHART:

Trial 2
Guppy: Even Mix
Predators: 30 Rivulus

60% of Brightest Guppies (10 generations)
9% of Bright Guppies(10 generations)
18% of Drab Guppies(10 generations)
13% of Drabbest Guppies(10 generations)

Trial 3
Guppy: Even Mix
Predators: 30 Rivulus, 30 Acara

8% of Brightest Guppies (10 generations)
70% of Bright Guppies(10 generations)
22% of Drab Guppies(10 generations)
0% of Drabbest Guppies(10 generations)

Trial 4
Guppy: Even Mix
Predators: 30 Rivulus, 30 Acara, 30 Cichlid

2% of Brightest Guppies (10 generations)
0% of Bright Guppies(10 generations)
9% of Drab Guppies(10 generations)
90% of Drabbest Guppies(10 generations)

Trial 5
Guppy: Mostly Bright
Predators: 30 Rivulus

75% of Brightest Guppies (10 generations)
20% of Bright Guppies(10 generations)
4% of Drab Guppies(10 generations)
1% of Drabbest Guppies(10 generations)

Trial 6
Guppy: Mostly Drab
Predators: 30 Rivulus, 30 Acara, 30 Cichlid

0% of Brightest Guppies (10 generations)
4% of Bright Guppies(10 generations)
12% of Drab Guppies(10 generations)
84% of Drabbest Guppies(10 generations)

8. Describe how predators influence guppy coloration.

The more predators there are, the less brightly colored guppies because the guppies don't want to attract attention.

9. Was your hypothesis correct, use your data to justify your answer.

My hypothesis was correct, because more predators made the number of brighter guppies drop, while drabber guppies became less prominent when there were few predators.
10. What does it mean that “male guppies live in a crossfire between their enemies and their would be mates”?

Male guppies can be harmed either direction they go color-wise. Bright colors attract mates and predators, while drab colors attract neither.

11. Why do you think guppies in different areas of the stream have different coloration?

Different areas of the stream have different predator numbers, affecting the coloring of the guppies.

12. What would happen to mostly drab guppies that were placed in a stream with very few predators?

Mostly drab guppies placed in a stream with few predators would become very flashy in time because of the low threat.

13. What would happen to brightly colored guppies that were placed in a stream with many predators?

Brightly colored guppies placed in a stream with many predators would eventually become drab due to the danger of having attention drawn to them.