Fossil fern showcases ancient chromosomes

Near-perfect 180-million-year-old sample shows the plants haven't changed much

By Meghan Rosen, 13:18 PM March 20, 2014

After 180 million years buried in volcanic rock in the southern tip of Sweden, a recently discovered fern fossil looks almost as good as new.

The matchbox-sized fossil is among the best ever preserved: Thin slices viewed under a microscope reveal rounded cells jam-packed in the stem, like water balloons stuffed in a barrel. And inside the cells, within tiny dots of nuclei, the shadowy squiggles of chromosomes appear.

Such exquisite detail was probably preserved when minerals dissolved in hot sa...

Source URL: https://www.sciencenews.org/article/fossil-fern-showcases-ancient-chromosomes