WHAT IS A SPECIES?
June 11, 2008
To this day, scientists struggle with determining what a species is. A better definition can influence which animals make the endangered list, says science essayist Carl Zimmer.
- Formal taxonomic systems first identified species based on visual traits, such as fins or fur.
- Later, the species concept changed, specifying that two organisms should be capable of breeding.
- Today biological diversity can be ascertained by sampling DNA and tracking how a species descended from a common ancestor.
The debate over species definition is far from over and is more than a mere academic spat; proper classification is essential for designating the endangered list, says Zimmer. Defining species can have a huge effect on whether an endangered group gets protected, and whether a habitat is saved or lost.
- The U.S. red wolf known as Canis rufus has been the subject of an enormous project to save it from extinction.
- Meanwhile, Canadian scientists argue that Canis rufus is just an isolated southern population of Canis lycaon, a Canadian wolf that is not endangered.
Source: Carl Zimmer, "What Is A Species?" Scientific American, June 2008.
Browse more articles on Environment Issues