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Origin of Species

Introduction | Storm | Pollenpeepers' New Homes | Windsor Island | Warwick Archipelago | Gallery

   Windsor Island    Warwick Archipelago

Description

A small island approximately five miles off the mainland coast.

A chain of four variously sized islands approximately 600 miles northeast of the mainland.

Habitat

Wetter, more lush, and more diverse than the mainland.

High diversity relative to the mainland. Individual islands are very different from one another, each boasting a wide range of habitat types, rainfall, and elevation.

Niches

Very few available niches, due to the large numbers and high diversity of bird species in and around the pollenpeepers' habitat.

Many niches available upon pollenpeepers' arrival, due to the island chain's distance from the mainland.

As you begin to investigate the evolution through time of the pollenpeepers on their new island homes, consider some important factors that drive evolution.

Habitat:
Habitat strongly directs the path of evolution. Change the habitat, or drop an organism into a new habitat, and you can expect evolutionary change -- usually rapid change in a very specific direction. Often, new habitats are ripe with opportunity because they've not had millions of years to become occupied by a diverse range of creatures. Niches remain open and free for the taking to any species able to use them.

Food:
Food is arguably the most important piece of a creature's habitat, driving the process of evolution, especially when its availability changes. Where food sources are diverse and plentiful, species can afford to be generalists, eating a wide variety of foods. A reduction in food availability, however, exerts intense pressure on a population, which collectively must find new food resources. Individuals best adapted for utilizing the resources that are available gain an advantage over others in the population. (Graphic illustrates food availability, not necessarily food consumption.)

Competition:
Competition may lead to divergence. Populations often diverge physically or behaviorally in ways that allow them to exploit different resources. This happens because individuals that differ sufficiently from their competitors in behavior or morphology can exploit different sets of resources better and thereby survive and reproduce better than individuals that have more in common with their competitors. Over generations, coexisting populations diverge in their patterns of resource, use and competition is reduced.

Predators:
Predators place limitations on their prey by restricting their movements and forcing populations to evolve defense strategies. When you take away predation pressures, you eliminate many limitations on how a species can evolve. In the absence of predators, novel traits can develop freely and persist, if they offer advantages to their owners. For example, flashy coloration may allow an individual to be more conspicuous to a potential mate. The result: a more widely diverse assemblage of organisms in predator-free environments than would otherwise be possible.

-> Explore pollenpeeper evolution on Windsor Island

Introduction | Storm | Pollenpeepers' New Homes | Windsor Island | Warwick Archipelago | Gallery

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