New Definition of 'Species' Could Aid Species Identification

Aug 24, 2006

Scientists at Texas Tech University argue that defining mammalian species based on genetics will result in the recognition of many more species than previously thought present. This has profound implications for our knowledge of biodiversity and issues based on it, such as conservation, ecology, and understanding evolution. Their study is published in the latest Journal of Mammalogy.

The classical definition of species was proposed by Ernst Mayr in 1942, defining it as reproductively isolated groups of organisms. According to this study, the problem with applying this concept is that it is hard to observe mating and to know whether there is interbreeding between populations and thus creation of hybrid species. Traditionally, species have been recognized based on physical characteristics, although it has been assumed that species differences are inherited and thereby reflect genetic differences.

Study researchers Robert Baker and Robert Bradley define “species” based on genetic data. The new definition distinguishes species that are genetically isolated from one another. Baker and Bradley’s genetic species concept also differs from the phylogenetic species concept proposed by Joel Cracraft in 1989 by emphasizing genetic isolation and protection of the integrity of the gene pool.

New molecular techniques for sequencing genes provide far greater resolution than was previously available. They also allow researchers to quantify problems in understanding the process of speciation. Using genetic data, it is now possible to distinguish species that are morphologically similar—those known as cryptic species. It is also possible to identify species that hybridize but have gene pools that are protected from one another.

The result of using genetic data is that species can be identified that cannot be distinguished using other methods. Baker and Bradley point out that this means there are doubtless many more species than previously thought. They hypothesize that there are 2,000 more mammalian species than are currently recognized.

According to the authors, this means that we will need to rethink the nature of speciation in mammals, barriers that evolve to produce genetic isolation between species, and how diverse mammals are, as well as other species-based issues such as those relating to conservation and zoonoses, communicable diseases from animals to humans.

To read the entire study, click here.

Source: Alliance Communications Group

Explore further: The inside story: MRI imaging shows how plants can inspire new engineering materials

Related Stories

Recommended for you

Can pollution help trees fight infection?

4 hours ago

Trees that can tolerate soil pollution are also better at defending themselves against pests and pathogens. "It looks like the very act of tolerating chemical pollution may give trees an advantage from biological ...

Improving rice flour to aid food poverty

4 hours ago

A new, high-quality rice flour could help towards aiding global food poverty. "This rice flour serves not only as an alternative to wheat flour for those with wheat intolerance, but could also help to overcome ...

Stink bugs have strong taste for ripe fruit

6 hours ago

The brown marmorated stink bug has a bad reputation. And for good reason: every summer, this pest attacks crops and invades homes, causing both sizable economic losses and a messy, smelly nuisance—especially ...

Researchers discover how petunias know when to smell good

8 hours ago

Good timing is a matter of skill. You would certainly dress up for an afternoon business meeting, but not an evening session of binge-watching Netflix. If you were just a few hours off in your wardrobe timing, ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.