Fleas are Members of Scorpionflies Family, New Study Finds

AP Photo In this Sept. 21, 2005, file picture a flea pulls a little cart at a flea circus performing at the Munich Oktoberfest beer festival. AP.
AP Photo In this Sept. 21, 2005, file picture a flea pulls a little cart at a flea circus performing at the Munich Oktoberfest beer festival. AP.
TT
20

Fleas are Members of Scorpionflies Family, New Study Finds

AP Photo In this Sept. 21, 2005, file picture a flea pulls a little cart at a flea circus performing at the Munich Oktoberfest beer festival. AP.
AP Photo In this Sept. 21, 2005, file picture a flea pulls a little cart at a flea circus performing at the Munich Oktoberfest beer festival. AP.

A study of more than 1,400 protein-coding genes of fleas has resolved one of the longest-standing mysteries by reordering the insect's placement in the tree of life.

The University of Bristol study, published in the journal Palaeoentomology, drew on the largest insect molecular dataset available. The dataset was analyzed using new statistical methods, including more sophisticated algorithms, to test all historically proposed hypotheses about the placement of fleas on the insect tree of life and search for new potential relationships.

The findings overturn previously held theories about fleas, the unusual anatomy of which has meant that they eluded classification in evolutionary terms. According to the authors of the study, fleas are technically scorpionflies, which evolved when they started feeding on the blood of vertebrates sometime between the Permian and Jurassic eras, between 290 and 165 million years ago.

The closest living relatives of fleas are the members of the scorpionfly family Nannochoristidae, a rare group with only seven species native to the southern hemisphere. Unlike the blood-thirsty fleas, adult nannochoristid scorpionflies lead a peaceful existence feeding on nectar. "Despite their medical significance as the cause of the deadliest pandemic in the recorded history of humankind, the placement of fleas on the tree of life represents one of the most persistent enigmas in the evolution of insects, and we can say that we successfully solved it," says lead author Erik Tihelka from the School of Earth Sciences in a report published on the university's website.

The Black Death, caused by a flea-transmitted bacterium, was the deadliest pandemic in the recorded history of humankind; it claimed the lives of possibly up to 200 million people in the 14th century. It used to be thought that all blood-feeding parasitic insects began life as either predators or by living alongside vertebrate hosts in their nests.

Explaining the link between scorpionflies' nectar feeding and fleas' blood feeding, Tihelka said "It seems that the elongate mouthparts that are specialized for nectar feeding from flowers can become co-opted during the course evolution to enable sucking blood."



Record Cold Grips Argentina, Chile and Uruguay

The three South American countries have all recorded sharply below-zero temperatures as the polar air originated from Antarctica and swept across the region. SEBASTIAN LOSADA / AFP
The three South American countries have all recorded sharply below-zero temperatures as the polar air originated from Antarctica and swept across the region. SEBASTIAN LOSADA / AFP
TT
20

Record Cold Grips Argentina, Chile and Uruguay

The three South American countries have all recorded sharply below-zero temperatures as the polar air originated from Antarctica and swept across the region. SEBASTIAN LOSADA / AFP
The three South American countries have all recorded sharply below-zero temperatures as the polar air originated from Antarctica and swept across the region. SEBASTIAN LOSADA / AFP

A polar air mass has brought record low temperatures to Argentina, Chile and Uruguay, causing at least 15 deaths and forcing governments to restrict gas supplies and activate emergency shelters.

The three South American countries have all recorded sharply below-zero temperatures as the polar air originated from Antarctica and swept across the region, said AFP.

In Argentina, at least nine homeless people have died from the cold this winter, according to NGO Proyecto 7.

The capital Buenos Aires recorded its lowest temperature since 1991 at -1.9 degrees Celcius (28.6 Fahrenheit) on Wednesday, while the coastal city of Miramar saw snow for the first time in 34 years. Further south, the town of Maquinchao recorded -18C on Tuesday.

Electricity demand caused cuts across Buenos Aires, leaving thousands without power for over 24 hours in some areas.

The government suspended gas supplies to industries and petrol stations Wednesday to ensure household supplies, and removed price controls on gas cylinders Thursday.

Desert snow

Uruguay declared a nationwide "red alert" after six people died, allowing President Yamandu Orsi's government to forcibly move homeless people to shelters.

Montevideo recorded its lowest maximum temperature since 1967 at 5.8C on June 30, according to meteorologist Mario Bidegain.

Chile also activated homeless shelter plans during the coldest days. The city of Chillan, 400 kilometers (250 miles) south of Santiago, hit -9.3C, according to the Chilean Meteorological Directorate.

"What happened this week in Chile and the Southern Cone in general is a cold wave caused by an escape of a polar air mass from Antarctica," climatologist Raul Cordero from the University of Santiago told AFP.

Snow even fell in parts of the Atacama Desert, the world's driest, for the first time in a decade.

"It is not so common for these cold air masses to extend so far north, so we cannot rule out that this is also caused by climate change," meteorologist Arnaldo Zuniga told AFP.

The region expects relief in the coming days, with Buenos Aires reaching 12C on Thursday, Montevideo 14C and Santiago 24.7C.

"I was quite surprised by the change from cold to hot -- the change was very drastic," student Dafne Naranjo, 18, said in Santiago.

Climatologist Cordero said heatwaves have become more frequent than cold spells in recent years.

"The frequency of heatwaves has tripled, whether in summer or winter, not only in the Southern Cone but throughout the world," he said.