Saving Holly
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Shantavira, Wikimedia Commons
A rare specimen of the King's Holly clone, growing in the Hobart Botanical Garden. Photo by Shantavira, Wikimedia Commons

When Neanderthals were mating with humans, when mammoth herds ruled the plains, giant lions prowled in proto-Britain and meter-tall hominids thrived on an isolated island Indonesian island – this plant was already alive. And now at the age of nearly 44,000 years, it is dying, a victim not of age but of root rot. Australian scientists still hope to save the species, however, by piggybacking it onto a similar plant with stronger roots.

At least, if not this plant, the genetically identical clone from which it propagated was alive. And now scientists are struggling to save the life of the magnificently unusual so-called "King's Holly," which isn't a holly at all, it's an asexual shrub from the family Proteaceae.

Lomatia tasmanica is special in having three sets of chromosomes, which renders it effectively sterile: there are no male and female forms, just the one. It reproduces by auto-cutting, meaning that when a piece falls off, it may take root and presto, you get a new plant – that is perfectly identical to the original one.

So technically, the plant scientists are striving to save doesn't have the same root set as the one 43,000 years ago, but it's the same plant. Once a lomatia starts growing, it can last about 300 years (which is pretty impressive in itself), but fossil evidence dates the surviving clones to at least 43,600 years and possibly three times as much.

One problem is that all surviving members of the breed still existing in the wild, in just one spot, are perfect clones. They are genetically identical, which means none have potentially better resistance to the revolting rot eating their roots alive.

As they all live in a small area of Tasmania, there's always the fear that wildfire will wipe them out, too.

One might think it trivial to break off pieces of one of the shrubs – they aren't that small – stick them in pots, and start growing them. But the plant turns out to hate that and grow very badly, if at all, and 20 years of trying haven't done much good.

"It doesn't like root disturbance so every time we pot it, we're losing plants, unfortunately," Natalie Tapson of the University of Tasmania's plant sciences school explained.

She and her colleagues are trying a new approach, to save this rare wonder from extinction: to graft bits of this doddering plant onto other – though similar – plants that have stronger roots.

The world crop of man's favorite bananas, the Cavendish, has a similar problem, by the way. Bananas also propagate asexually and the world crop is almost completely genetically identical - and is also under threat from a deadly fungus, albeit a different one. It is entirely possible that soon, man will have to make do with a less popular banana species.