The Royal Botanic Garden Sydney's Daniel Solander Library is crammed full of fascinating artefacts. In the first instalment of a new series, librarian Miguel Garcia dips into its storied collection.
Some fungi are delicious, others are downright unpleasant and it pays to give them a wide berth. If I told you the Garden is home to a century-old ‘zombie fungi’, you might assume it falls into the latter category. You’d be dead wrong.
‘Zombie fungi’ are part of two fascinating – albeit slightly macabre – taxonomic groups called Cordyceps and Ophiocordyceps. And they, or something similar, have been found in trace fossils as early as 48 million years ago. In more recent times they’ve been depicted, often horrifically, in cinema, television, novels and even computer games.
Fortunately, despite the dramatic embellishments by the arts, these parasitic fungi do not trouble humans or indeed any warm-blooded species. Their hosts are generally invertebrates especially insect larvae. Their life cycle begins with spores, scattered in the soil. Upon contact with larvae, the spores release mycelia – a network of very fine threads that spreads throughout the host, eventually intruding into its nervous system and brain. This is where the ‘zombie’ emerges.
Instead of remaining safely below the surface, the larva is compelled to burrow towards the surface, in a vertical position with head oriented upwards. At this point it dies and from its head a ‘fruiting body’, the spore producing structure, bursts out as a stalk, emerging from the soil to spread more spores, completing the zombie’s life cycle. These zombie fungi are not just fuel for our nightmares.
One species, Ophiocordyceps sinensis is classified as medicinal, and it has a long history in traditional Chinese, Nepalese and Tibetan medicine, with the fungusaffected larva highly valued for treatment of many maladies and as an aphrodisiac. In traditional Chinese medicine the fungus is called the “insect plant” and is regarded as having an excellent balance of yin and yang as it is thought to be a combination of both animal and vegetable.
Today, the zombie fungus is collected by hand and the mycelia cultured in grain or liquid mediums. The active medicinal component is Cordycepin and scientific investigation suggests it has uses in treating cancers, depression, diabetes and heart disease. At least one clinical trial as a leukemia treatment has also been conducted since 2015.
And in Australia, a local species, Cordyceps gunnii, has been known to fetch as much as $4,000 per 100 grams. The Garden’s own zombie – a Cordyceps gunnii most likely collected by Scottish propagator Alexander Grant back in the 1890s – resides in a spirit jar in the Daniel Solander Library.
Grant served his apprenticeship in the gardens of the Earl of Seafield, Cullen House, Banffshire and later at the Royal Botanic Gardens, Edinburgh. He left for Australia and arrived in Sydney in 1878.
From 1882 Grant was employed in the Botanic Gardens, Sydney as a propagator. He specialised in fungi and was employed as a mycologist by the Department of Agriculture. He was vice-president of the Horticulture Association from its foundation.
In 1899, Grant added some 120 glass jars of fungi in spirits to what was then the Garden’s Botanical Museum Collection. If you’d like to take a look, don’t be afraid to ask. Just be sure to book an appointment – we’re open Tuesday– Thursday, 10am–4pm.
This article was written for the Foundation & Friends of the Botanic Gardens Magazine as seen in the Winter Issue here.