Now, the first genetic study of the diversity of clinging jellyfish populations around the globe has discovered some surprising links among distant communities of jellies and also revealed there may be more than one species of the infamous stinger.
The new study shows that the story is much more complex than previously thought. The researchers uncovered a genetic match between populations of clinging jellyfish in the Vladivostok, Russia-area — specifically the area well known to cause severe sting reactions — and those found along the U.S. East Coast in the Northwest Atlantic.
“We know the two regions share one genetic variant or haplotype,” Govindarajan says. “In the Northwest Atlantic, this variant was actually most frequently found in eastern Long Island Sound. The details about how and when an invasion, or possibly multiple invasions, occurred aren’t clear. Interestingly, we also found evidence that both regions may contain native forms.”
“In the past, some people have suggested that the Atlantic and the Pacific jellies were different forms,” Govindarajan says. “Others have suggested that jellies in the Atlantic were introduced from the Pacific. But what we found doesn’t correspond exactly to either hypothesis. And it could be that what we have in the Northwest Atlantic and Northwest Pacific is not Gonionemus ‘vertens’ at all, as it has been called, but some other species of Gonionemus.”
“The study documents what we suspected, that there are different types of Gonionemus jellies and some of these types co-occur in New England,” says coauthor Carman. “Some types seem to have a toxic sting to people and some do not.” Understanding the relationship between the genetic variants and toxicity is something the researchers would like to pursue in the future. “It could very well be that the toxicity is a function of both genetics and the environment, perhaps something in the environment is triggering the toxicity,” Govindarajan says.Paper. (public access) – Annette F. Govindarajan, Mary R. Carman, Marat R. Khaidarov, Alexander Semenchenko, John P. Wares. Mitochondrial diversity in Gonionemus (Trachylina:Hydrozoa) and its implications for understanding the origins of clinging jellyfish in the Northwest Atlantic Ocean. PeerJ, 2017; 5: e3205 DOI: 10.7717/peerj.3205 More.
It “could very well be” that the entire concept of speciation is a mess. There is no rigorous approach to what a species even is.
Reality check: The obsessive hunt for the few and rare species that can be shown to be produced by explicitly Darwinian means (natural selection acting on random mutation) sidetracks reform. The light more rigorous approaches can shed will tend to make Darwinism even less plausible.
See also: Researchers: Jellyfish cousin devolves to parasite “The finding represents the first case of extreme evolutionary degeneration of an animal body.”
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