Scientists identified bed bugs as the first plague of humans. Although not patients with diseases, 60,000 years later, we remain the main course of their menu.
Insects represent 90% of the planet’s animals – and there is a long time to call “pests” to many of them. But what was the first human plague?
A study this Wednesday in Biology Letters found that bugs It was the first species that “tasted” for humans.
60,000 years Then we remain the main course of your menu.
The investigators of Virginia Tech They have made this discovery after comparing the genomes of two distinct strain lines – one that is suspected of having caught a Neanderthal ride a thousands of years ago and another who remained true to his bat host.
It was found that while the population of insects that fed on bats has decreased over thousands of years, the bed bugs we know today evolved as humans evolved – Which puts them as our oldest known “pest”.
“Initially, with both populations, we watched a general decline that is consistent with the last maximum glacial. In turn, the bat lineage has never recovered and continues to decrease in size,” he told, Ao, Lindsay Milesmain author and researcher of the Department of Entomology at Virginia Tech.
“The really exciting part is that the line -associated lineage has recovered and its effective population has increased,” he added.
Resist 60,000 years ago
The approximately 90 arthropod species have always shared a stable symbiotic relationship with their hosts – until human ancestors began to form societies and live closely proximity.
It was then that the ordinary bugCimex lectularius) to Tuporo tropical (Cimex hemipterus) Forged a lasting path of survival.
“This makes sense because modern humans have left caves about 60,000 years ago,” he told Ne Warren Booth, an associate professor of entomology at Virginia Techin New Atlas.
“There were bugs to live in the caves with these humans, and when they left, they took a subset of the population, so there is less genetic diversity in this line -associated lineage,” he added.
Why are they so resistant?
The study also identified a genetic mutation that made the bed bugs so resistant to an previously effective insecticide: the DDT [dicloro-difenil-tricloroetano].
The bed bugs were very common in the ancient world, but when the DDT was introduced to pest control, the populations fell. It was thought that they had been essentially eradicated, but within five years they began to reappear and resist the pesticide.
However, the progressive elimination of the DDT, the increase in international travel and the growing urban population density, the number of bed bugs exploded. In 2006, Australian pest control professionals estimated that infestations increased 4,500% in a year.
“The moment and the magnitude of demographic patterns provide convincing evidence that the lineage associated with humans has closely followed the demographic history of modern humans and their movement to the first cities. As such, bed bugs can represent the first true species of urban pest insect“The investigators concluded.
