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Cover-Alien Invaders

TPW Magazine, January 2010
If you don't have a copy of the TPW magazine, you may print a copy of Alien Invaders!

Definitions and Context

Adaptation: traits developed over time that help organisms meet their basic needs and survive.
Context: The adaptation of thorns discourages animals from munching on juicy cactus.

Ballast water: water carried in the bottom of a boat for stability
Context: When ballast water is collected from a natural body of water it can carry plants and animals to new homes.

Banned: forbidden by law
Context: Apple snails are banned in Texas; no person may import, possess, sell, or place them into water of this state except as authorized by rule or permit.

Exotic: a species that is not native to a certain region
Context: Ringtail cat are native to Texas, but exotic to England.

Generalist: organisms that can use a wide variety of food, water sources and living spaces
Context: Invasives are often generalists, finding ways to survive in new surroundings.

Habitat: place where an animal or plant naturally lives or grows, eats, drinks, and finds the shelter it needs
Context: The golden-cheeked warbler finds its habitat in the oak cedar woodlands of central Texas.

Invasive: a species that grows or reproduces quickly, spreads and lives over time
Context: Giant salvinia is an invasive plant because it grows so quickly and chokes out other plants in its habitat.

Native: a species that originated in a certain region
Context: Bluebonnets are native to central Texas.

Population: the number of a particular species in a defined area.
Context: The population of Gulf Coast Toads in this watershed may be affected by the use of pesticides upstream.

Preserve: an area that is set aside to protect and preserve natural resources
Context: Students worked to clear invasives from a preserve.

Specialist: organisms that have very specific requirements for food, water sources or living spaces. They often utilize a very specialized food source or living space and are very successful as long as the food or space is available.
Context: Endangered species are often specialists that have lost their unique food or homes.

Species: a population that are more or less alike and that are able to breed and produce fertile offspring under natural conditions; a category of biological classification immediately below the genus or subgenus.
Context: Black-capped vireo and golden-cheeked warbler are two different bird species that depend on central Texas habitat to survive.

Survive: stay alive
Context: All living things need habitat; food, water, shelter, and space in a proper arrangement to survive.