Wednesday, October 27, 2010

Sex and the Single Guppy

1. Even though bright colors attract predators, the coloration of the guppies depend on where they are in the stream. It varies with each stream or river, and through different parts of the stream. Bright colors also attract mates. A scientist, Endler, wanted to test these discoveries, finding this as his results.

2. After viewing the fish gallery, I think that the Poecilia reticulata is my favorite fish. The origin of this fish is Brazil. It's average size is about 3.5 centimeters. It is a male, so it has many bright colors. It is probably the brightest of the gallery of fish. It is mostly dark blue on the top side of the fish, but towards the bottom, it has splotches of yellow and green. The tail is green and the dorsal fin is orangish.

3. After viewing the predator gallery, I think the Fat Sleeper, or the Dormitator maculatus, is the most interesting of the predators. It has distributed to Southern North America, Bahamas, and Latin America.

4. The size of the body of water and the size of the predator fish will affect the predator population.

5. John Endler is an evolutionary biologist who began studying wild guppies in the 1970s. He studied it in various streams and found that the coloration of the guppy depends on where the guppies are.

6. Pool 1: Brightly Multi Colored with large spots.
Pool 2: Medium coloration on body and tail, with medium sized spots.
Pool 3: Drab coloration, very small spots concentrated near tail.

7. I think in different parts of the stream, the coloration of the guppies vary depending on the amount of predators and females in that particular part of the stream. I think that bright guppies will last the longest, because they attract mates, and the rest depends on the amount of predators in the area.

% of Brightest Guppies
(10 generations)

% of Bright Guppies
(10 generations)
% of Drab Guppies
(10 generations)
% of DrabbestGuppies
(10 generations)

Trial 1

Guppy: Even Mix
Predators
: 30 Rivulus

57% 25% 14% 5%

Trial 2

Guppy: Even Mix
Predators
: 30 Rivulus, 30 Acara

4%61% 35% 0%

Trial 3

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

0% 11% 7%82%

Trial 4

Guppy: Mostly Bright
Predators
: 30 Rivulus

64% 30% 5% 2%

Trial 5

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

0% 0% 0% 100%


8. Predators influence guppy coloration because they can spot the brightly colored ones ore easily than the drab ones. So depending on the amount of predators in the area, there with be more/less brightly colored ones.

9. My hypothesis was not correct because depending on the variables, there were more drab guppies than bright guppies.

10. I think it means that male guppies health depends on reproducing, and not being eaten. Male guppies depend on others to stay healthy.

11. In different areas of the stream, there are more or less predators, and depending on the amount of predators, there is a greater population of guppies.

12. If mostly drab guppies were placed in a stream with very few predators, they would probably overrun the predators because drab guppies are harder for the predators to spot, so eventually the predators would die out.

13. If brightly colored guppies were placed in a stream with many predators, the predators would overrun because the bright colored guppies are easier to spot, and eventually would die out since there are so many predators.

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