Seemingly identical animals on the outside may in fact be completely different species, according to scientists who have made a startling discovery that could have widespread implications for biology.
Researchers from the University of Gothenburg, Sweden, have discovered with DNA analysis that a common segmented worms is actually two different species. The two different species have been treated as one since they were first described. Called Lumbriculus variegates , or commonly known as blackworm, the worms inhabit freshwater environments in North America and Europe.
 The blackworm has always been considered one species, until recent DNA analysis showed it was two. Photo courtesy of: Biopix. |
“We could be talking about a large number of species that have existed undiscovered because they resemble other known species,” says Professor Christer Erséus, one of the authors of the study which appeared in the journal Molecular Phylogenetics and Evolution .
Erséus and his colleagues found that the two look-alike worms differed genetically by an incredible 17 percent, twice as much as humans differ from chimpanzees.
Blackworms have been used frequently for testing the effect of environmental toxins. But the discovery that the one species is actually two could shake-up any previous findings.
“Different species have different characteristics. If it emerged that these two species differ in terms of their tolerance towards certain toxins, then it could be difficult to make comparisons between different studies,” explains Erséus.
The implications of the discovery could also range far beyond the blackworm. Giving such DNA tests to other animals may overturn current ideas about biodiversity.
“There could be ten times as many species in total, compared with what we previously thought,” Erséus says.
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