But looked at another way, don't we humans ourselves have many of the characteristics of weedy species?
Characteristics of weeds and weedy species (as we humans have defined them):
- They interfere with activities we value, such as the way we want our gardens to look, the production of crops and livestock at least cost, other economic activities, or our use of the environment.
- They crowd out other species we would prefer to have at that site.
- They crowd out native species already growing there.
- They are directly toxic or otherwise bothersome to us (think of poison ivy).
- They are costly or difficult to prevent or remove.
- They tend to reproduce prolifically and occupy vacant or disrupted environments.
- They are often versatile in terms of habitat, nutrition, and interaction with other species--flexible and adaptable.
- Examples are rats and mice, or other species when introduced in new environments without their natural predators (dogs, prickly pear cactus in Australia)
Those Pesky Humans!
- They have invaded virtually every habitat on Earth except underwater zones (and will probably find a way to colonize Mars).
- They can out-compete any other species that occupies territory they want or that threatens them.
- They can reproduce rapidly when constraints of disease are removed by their technology.
- They have become one of the dominant species on the planet in just a few thousand generations.