Metal-Absorbing Plants Could Make Mining Greener | A Tiny Fern's Gigantic Genome

Episode 792,   Jun 12, 08:00 PM

Plants called “hyperaccumulators” have evolved to absorb high levels of metals. Scientists want to harness them for greener metal mining. And, a little fern from New Caledonia is just a few inches tall, but its genome has 160.45 billion base pairs—50 times more DNA than a human.

How Metal-Absorbing Plants Could Make Mining Greener

Scientists are exploring a somewhat unusual green energy solution: mining metals from the earth using plants.

Typically, if soil has high levels of metal, plants will either die or do everything they can to avoid it. But, one group has taken a different path: evolve to be able to safely absorb large amounts of the metals. These special plants are called hyperaccumulators. And their ability to suck metals like nickel from the earth is called phytomining.

The Department of Energy’s Advanced Research Projects Agency-Energy announced in March up to $10 million in funding for phytomining research.

Ira talks with Dr. David McNear, professor of plant and soil sciences at the University of Kentucky, about these fascinating flora and their promise as a greener option to metal mining.

A Tiny Fern Has The Largest Genome Ever Discovered

Scientists just discovered the largest genome of any living thing on Earth, and it belongs to a small, unassuming fern called Tmesipteris oblanceolata. If you were to split open one of its cells and unwind the DNA that’s coiled up in the nucleus, it would stretch out more than 300 feet—taller than the Statue of Liberty.

Scientists reported the finding last week in the journal iScience. The fern is only a few inches tall and is found on the island of New Caledonia in the Southwest Pacific. Its DNA is made up of 160.45 billion base pairs—50 times more than the human genome.

This finding has left scientists scratching their heads, wondering how and why a fern ended up with so much DNA. Ira Flatow talks with co-lead author of this study Dr. Jaume Pellicer, evolutionary biologist at the Botanical Institute of Barcelona, about this research and why this fern’s DNA is so puzzling.

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