Canadian Scientists Retrieve DNA of Extinct Animals from Soil

Vials containing engineered DNA(Getty Images)
Vials containing engineered DNA(Getty Images)
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Canadian Scientists Retrieve DNA of Extinct Animals from Soil

Vials containing engineered DNA(Getty Images)
Vials containing engineered DNA(Getty Images)

Researchers at McMaster University have developed a new technique to tease ancient DNA from soil, pulling the genomes of hundreds of animals and thousands of plants which many of them are long extinct.

The DNA extraction method, outlined in the journal Quarternary Research, allows scientists to reconstruct the most advanced picture ever of environments that existed thousands of years ago.

According to a report published by the University of McMaster, this technique retrieves the ancient DNA by using the cells constantly shed by organisms throughout their lives.

"Organisms are constantly shedding cells throughout their lives. Humans, for example, shed some half a billion skin cells every day. Much of this genetic material is quickly degraded, but some small fraction is safeguarded for millennia through sedimentary mineral-binding and is out there waiting for us to recover and study it. Now, we can conduct some remarkable research by recovering an immense diversity of environmental DNA from very small amounts of sediment, and in the total absence of any surviving biological tissues," explained evolutionary geneticist Hendrik Poinar, a lead author on the paper.

The researchers used their technique to analyze soil samples from four sites in the Yukon region, each representing different points in the Pleistocene-Halocene transition, which occurred approximately 11,000 years ago.

This transition featured the extinction of a large number of animal species such as mammoths, mastodons and ground sloths, and the new process has yielded some surprising new information about the way events unfolded.

"In the Yukon samples, we found the genetic remnants of a vast array of animals, including mammoths, horses, bison, reindeer and thousands of varieties of plants. The scientists determined that woolly mammoths and horses were likely still present in the Yukon's Klondike region as recently as 9,700 years ago, thousands of years later than previous research using fossilized remains had suggested," Poinar said.



New Searches Underway in Portugal Near Where Madeleine McCann Disappeared in 2007

 A Portuguese official during a search operation in a vast area between the cities of Lagos and Praia da Luz for Madeleine McCann, in Lagos, Portugal, 03 June 2025. (EPA)
A Portuguese official during a search operation in a vast area between the cities of Lagos and Praia da Luz for Madeleine McCann, in Lagos, Portugal, 03 June 2025. (EPA)
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New Searches Underway in Portugal Near Where Madeleine McCann Disappeared in 2007

 A Portuguese official during a search operation in a vast area between the cities of Lagos and Praia da Luz for Madeleine McCann, in Lagos, Portugal, 03 June 2025. (EPA)
A Portuguese official during a search operation in a vast area between the cities of Lagos and Praia da Luz for Madeleine McCann, in Lagos, Portugal, 03 June 2025. (EPA)

Police investigating the disappearance of British toddler Madeleine McCann searched near an abandoned rural building in southern Portugal on Tuesday as they launched fresh probes near the holiday resort where she was last seen 18 years ago.

The case received worldwide interest for several years, with reports of sightings of McCann occurring as far away as Australia, while books and television documentaries were produced about her disappearance.

German investigators and Portuguese police officers and firefighters were searching in the countryside several miles from the Praia da Luz resort, where the 3-year-old disappeared from her bed while on vacation with her family on May 3, 2007.

The teams were seen using pickaxes, shovels and chainsaws to clear dense vegetation and dig near a derelict building. Firefighters pumped water out of a well.

Almost two decades on, investigators in the UK, Portugal and Germany are still piecing together what happened on the night the toddler disappeared. She was in the same room as her brother and sister — 2-year-old twins — while their parents, Kate and Gerry, had dinner with friends outside.

Portuguese police said Monday that detectives were acting on a request from a German public prosecutor as they carry out “a broad range” of searches this week in the area of Lagos, in southern Portugal.

The main suspect is a German national identified by media as Christian Brueckner, who is currently serving a seven-year prison sentence in Germany for raping a 72-year-old woman in Portugal in 2005.

He is under investigation on suspicion of murder in the McCann case but hasn’t been charged. He spent many years in Portugal, including in Praia da Luz, around the time of the child’s disappearance. Brueckner has denied any involvement.

The last time police resumed searches in the case was in 2023, when detectives from the three countries took part in an operation searching near a dam and a reservoir about 50 kilometers (30 miles) from the resort.

McCann's family marked the 18th anniversary of her disappearance last month, and expressed their determination to keep searching.