Exp Appl Acarol. 2009 Jan;47(1):1-18. Epub 2008 Oct 18.
First divergence time estimate of spiders, scorpions, mites and ticks (subphylum: Chelicerata) inferred from mitochondrial phylogeny.
Jeyaprakash A, Hoy MA.
Department of Entomology and Nematology, University of Florida, Gainesville, FL 32611, USA. email@example.com
Spiders, scorpions, mites and ticks (chelicerates) form one of the most diverse groups of arthropods on land, but their origin and times of diversification are not yet established. We estimated, for the first time, the molecular divergence times for these chelicerates using complete mitochondrial sequences from 25 taxa. All mitochondrial genes were evaluated individually or after concatenation. Sequences belonging to three missing genes (ND3, 6, and tRNA-Asp) from three taxa, as well as the faster-evolving ribosomal RNAs (12S and 16S), tRNAs, and the third base of each codon from 11 protein-coding genes (PCGs) (COI-III, CYTB, ATP8, 6, ND1-2, 4L, and 4-5), were identified and removed. The remaining concatenated sequences from 11 PCGs produced a completely resolved phylogenetic tree and confirmed that all chelicerates are monophyletic. Removing the third base from each codon was essential to resolve the phylogeny, which allowed deep divergence times to be calculated using three nodes calibrated with upper and lower priors. Our estimates indicate that the orders and classes of spiders, scorpions, mites, and ticks diversified in the late Paleozoic, much earlier than previously reported from fossil date estimates.
The divergence time estimated for ticks suggests that their first land hosts could have been amphibians rather than reptiles. Using molecular data, we separated the spider-scorpion clades and estimated their divergence times at 397 +/- 23 million years ago. Algae, fungi, plants, and animals, including insects, were well established on land when these chelicerates diversified. Future analyses, involving mitochondrial sequences from additional chelicerate taxa and the inclusion of nuclear genes (or entire genomes) will provide a more complete picture of the evolution of the Chelicerata, the second most abundant group of animals on earth.
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15 milj v vanhasta punkista löydettiin merkkejä borreiabakteerin kaltaisesta bakteerista. Bakteerii löydettiin meripihkan sisällä olevasta punkista.
Fifteen Million-Year-Old Tick Found Carrying Disease Resembling Lyme Disease.
The Los Angeles Times (5/30, Morin) reports recent research published in Historical Biology found a tick trapped 15 million years ago in an amber droplet may have been infected with a bacteria resembling Lyme disease. The tick was found in the present-day Dominican Republic. Of four ticks found, only one appeared to carry the disease, “suggesting that it either inherited the bacteria from its mother or obtained it from an animal it had seized on for a blood meal.”
Science/ Science Now
Ticks may have carried Lyme disease for more than 15 million years
A 15- to 20-million-year-old tick encased in amber appears to have been infected with a bacteria similar to the one that causes Lyme disease in humans, a new study says. (George Poinar Jr.)
By Monte Morin contact the reporter
This article is related to: Diseases and Illnesses, Dominican Republic, Biology
Lyme disease may be much, much older than we previously thought
Tiny ticks may have carried Lyme disease bacteria for more than 15 million years
May 29, 2014, 4:09 PM
A tiny tick trapped in a droplet of amber more than 15 million years ago appears to have been infected with a bacteria similar to the one that causes Lyme disease in humans, according to new research..
In a paper published recently in the journal Historical Biology, one of the world's leading experts on amber-preserved specimens found a multitude of corkscrew-like bacteria in the belly of a young Ambylomma tick.
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The bacteria, according to study author George Poinar Jr., a professor emeritus in the Department of Integrative Biology at Oregon State University, appeared very similar to bacteria of the Borrelia genus, a species of which causes Lyme disease.
The larval tick was one of four that was trapped in drops of tree resin 15 to 20 million years ago in what is now the Dominican Republic, according to the author.
"The time of death of organisms in resin occurs immediately after entombment and tissue preservation begins instantly," Poinar wrote.
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Over time, the resin hardened into amber and was buried beneath successive layers of earth, as well as plant and animal matter. The specimens were discovered in the modern age by miners who tunnel for amber fossils.
Poinar said that only one of the four ticks appeared to be infected with the bacteria, suggesting that it either inherited the bacteria from its mother or obtained it from an animal it had seized on for a blood meal.
Although the tick's insides showed no signs of blood, Poinar said it was possible the animal knocked it away moments after it was infected.
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Lyme disease, which causes a variety of symptoms, including headaches, joint pain, fever and fatigue, has only been recognized by medical experts in the last few decades.
However, Poinar argues that ticks have been harboring a variety of bacteria that are harmful to humans and other hosts for millions of years.
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In another recent paper published in the journal Cretaceous Research, Poinar examined fossil ticks from Myanmar and observed microbes similar to Rickettsia bacteria, which cause Rocky Mountain spotted fever. That amber-encased tick was estimated to be between 97 and 110 million years old.
"It's likely that many ailments in human history for which doctors had no explanation have been caused by tick-borne disease," Poinar told OSU science writer David Stauth.
Scientists say the oldest case of tick-related disease belongs to Otzi the Tyrolean iceman. The ancient European died in the Alps about 5,300 years ago - under what appear to be a variety of trying circumstances - and his mummified remains were discovered by hikers in 1991.
"Before he was frozen in the glacier, the iceman was probably already in misery from Lyme disease," Poinar said.
soijuv Viestit: 2907Liittynyt: Ke Tammi 21, 2009 11:16
Tick Museum- http://cosm.georgiasouthern.edu/icps/co ... ion-usntc/
Proc Natl Acad Sci U S A. 2002 Feb 5;99(3):1410-3. Epub 2002 Jan 29.
Spirochete and protist symbionts of a termite (Mastotermes electrodominicus) in Miocene amber.
Wier A, Dolan M, Grimaldi D, Guerrero R, Wagensberg J, Margulis L.
Department of Geosciences, University of Massachusetts, Amherst, MA 01003, USA.
Extraordinary preservation in amber of the Miocene termite Mastotermes electrodominicus has led to the discovery of fossil symbiotic microbes. Spirochete bacteria and wood-digesting protists were identified in the intestinal tissue of the insect. Fossil wood (xylem: developing vessel-element cells, fibers, pit connections), protists (most likely xylophagic amitochondriates), an endospore (probably of the filamentous intestinal bacterium Arthromitus = Bacillus), and large spirochetes were seen in thin section by light and transmission electron microscopy. The intestinal microbiota of the living termite Mastotermes darwiniensis, a genus now restricted to northern Australia, markedly resembles that preserved in amber. This is a direct observation of a 20-million-year-old xylophagus termite fossil microbial community.
PMID: 11818534 [PubMed - indexed for MEDLINE]PMCID: PMC122204Free PMC Article
J of Infect Dis. 2005 Feb 15;191(4):607-11. Epub 2005 Jan 10.
Bartonella quintana in a 4000-year-old human tooth.
Drancourt M1, Tran-Hung L, Courtin J, Lumley Hd, Raoult D.
Bacteria of the genus Bartonella are transmitted by ectoparasites (lice, fleas, ticks) and have mammalian reservoirs in which they cause chronic, asymptomatic bacteremia. Humans are the reservoir of B. quintana, the louse-borne agent of trench fever. We detected DNA of B. quintana in the dental pulp of a person who died 4000 years ago.
PMID: 15655785 [PubMed - indexed for MEDLINE] Free full text
J Infect Dis. 1994 Oct;170(4):1027-32.
Detection of Borrelia burgdorferi DNA in museum specimens of Peromyscus leucopus.
Marshall WF 3rd1, Telford SR 3rd, Rys PN, Rutledge BJ, Mathiesen D, Malawista SE, Spielman A, Persing DH.
1Department of Tropical Public Health, Harvard School of Public Health, Boston, Massachusetts.
To determine whether Borrelia burgdorferi was enzootic within the United States at the beginning of the 20th century, ear skin samples taken from museum specimens of the white-footed mouse (Peromyscus leucopus) were examined for evidence of spirochetal DNA. In total, 280 samples from mice collected between 1870 and 1919 were analyzed by a nested polymerase chain reaction protocol. Of these, 2 specimens from the vicinity of Dennis, Massachusetts, during 1894 were reproducibly positive for B. burgdorferi OspA sequences. The remaining 278, representing both currently endemic and nonendemic sites, were negative for spirochetal DNA. These studies suggest that the agent of Lyme disease was present in a suitable reservoir host in the United States before the turn of the century and provide evidence against a hypothesis of recent introduction of this zoonotic agent to North America.
World's Oldest Tick Found in New Jersey
By Rose Palazzolo
What scientists believe to be the world's oldest known tick was found embedded in amber from a vacant lot in central New Jersey.
The 90-million-year-old tick is just one find from a bushel of amber located in the vacant lot in Sayerville which has yielded some of the world's most scientifically important amber specimens from the Cretaceous Period, according to David Grimaldi, chairman and curator, Entomology Department of the American Museum of Natural History. Grimaldi refers to the lot as the "amber mother lode."
He co-authored a report in the current Annals of Entomological Society of America with Ohio State University assistant professor of entomology Hans Klompen on the latest tick discovery. Eighty pounds of amber have been drawn out of deep mud in a complex of sites in central New Jersey.
90 Million-Year-Old Tick
The tick discovery is a significant find, says Grimaldi, because it will help scientists make inferences as to what dinosaurs and birds ate 90 million years ago. The find also pushes back the age of the order of parasitic mites (the order that ticks come from) by 50 million years.
"This specimen is the oldest tick fossil and is very similar to the modern genus," said Grimaldi.
Not only is the soft tick, named Carlos Jerseyi, the oldest known tick it's also the oldest representative of parasitic mites with one significant difference — it has a hairy back.
Hairs lining the tick's back were the most unusual aspect of this tick. Researchers suspect the hairs gave the tick extrasensory perception, but why that would be an advantage for the ancient tick is not known. One thing scientists do believe they understand is what the hairy tick may have been feeding on.
"There were feathers found in the amber in New Jersey from birds," said Grimaldi. "We know some dinosaurs had feathers and now we know that parasites fed on these birds and dinosaurs at a fairly early age. But we believe this tick was transported to New Jersey by a South American bird."
Researchers have theorized that ticks originated in South America. Dinosaurs, turtles, lizards, frogs and primitive birds, also dinosaurs, are believed to have roamed New Jersey 90 million years ago. Grimaldi says the find further indicates that parasites were around from the very beginning.
Tick — the Downfall of Dino?
"It's likely that dinosaurs carried ticks," Grimaldi said.
Researchers studying the ancient ticks are probing whether the creatures may have carried parasites that impaired ancient dinosaurs and perhaps even led to some of their extinction.
Other finds from the New Jersey lot include the oldest mushroom, the oldest flower in amber, the oldest ants, and the oldest feather from a terrestrial bird in North America. Other biting insects, like the tick, have also been found, making extraction of dinosaur DNA a possibility.
The discovery of the young tick came somewhat as a surprise to researchers. As Grimaldi was grinding and polishing the amber he thought he came upon a large mite. But then when he could see the distinct tick markings he knew it was a rare find.
"After I spotted the distinct mouth and legs I realized this was a tick," Grimaldi said. "A beautiful, juvenile tick."
The site was discovered about five years ago by Gerard Case, a fossil hunter.