Howard Falcon-Lang, Royal Holloway University of London

World’s oldest pine tree fossil found in Canadian rock quarry

Scientists have found a 140-million-year-old pine tree fossil, the oldest known, in a Canadian rock quarry. The charred twig (seen above) has small divots where pine needle shoots once sprang forth, and analysis of the internal woody material has revealed ducts that once carried sticky resins. The fossil, just a half-a-centimeter in diameter, was found after researchers used acid to dissolve a rock sample from a gypsum quarry in Nova Scotia, Canada, they report this week in the journal Geology. Pine trees belong to the most widespread genus in the world, and scientists want to know how and when they evolved. The new find is as much as 11 million years older than the previous record holder, suggesting that pine trees came on to the scene even earlier than expected. Scientists weren’t surprised to find the fossil charred from a fire. At the time the pine tree was alive, the world was in a greenhouse, and oxygen levels and temperatures were high—prime conditions for fires. Pine trees, containing flammable resins, have evolved to aid and abet fires so that their pine cones can germinate on the charred forest floor, free of competitors.