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Sex and the Single Guppy

Intro | Discovery | Hypotheses | Simulation 1 | Analysis 1 | Simulation 2 | Analysis 2 | Conclusion | Gallery


Guppy Gallery | Common Guppy Predators | Trinidad Guppy Habitat

Here are some images of typical guppy habitats on Trinidad, an island off the coast of Venezuela. Guppies usually occupy the entire length of a stream, from the trickling headwaters to the much wider and deeper mouth. Dams like the ones seen here often restrict the upstream movement of some of the more voracious predators, confining them to the lowermost sections of a stream.


A section of stream like this deep pool on Trinidad's Aripo River would not only contain guppies, but also hungry predators.


Dams such as the one seen here restrict predatory fish movements. A guppy population above the dam would enjoy little to no predation pressure.


Dams no bigger than this often keep some predators from moving upstream. Guppies in the pools just above would face moderate predation levels.

shallow pool

Only the smallest and least-effective guppy predators would likely find their way into this shallow pool.


Even trickles like this tributary of the Quare River in Trinidad can sustain guppy populations, so long as they contain water year-round.

Intro | Discovery | Hypotheses | Simulation 1 | Analysis 1 | Simulation 2 | Analysis 2 | Conclusion | Gallery

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