Guardian: Climate Change Killed off Ancient Rome’s Herbal Viagra

Essay by Eric Worrall

New Hampshire professors claim the ancient Silphium herb herb died from climate change, not because greedy Romans picked every last plant.

Caesar’s favourite herb was the Viagra of ancient Rome. Until climate change killed it off

Perfume, tonic – even love potion – silphium was prized by the ancient Romans, but in its success lay the seeds of its own downfall

James Tapper Sun 15 May 2022 19.00 AEST

Of all the mysteries of ancient Rome, silphium is among the most intriguing. Romans loved the herb as much as we love chocolate. They used silphium as perfume, as medicine, as an aphrodisiac and turned it into a condiment, called laser, that they poured on to almost every dish. It was so valuable that Julius Caesar stashed more than half a tonne in his treasury.

Yet it became extinct less than a century later, by the time of Nero, and for nearly 2,000 years people have puzzled over the cause.

Researchers now believe it was the first victim of man-made climate change – and warn that we should heed the lesson of silphium or risk losing plants that are the basis of many modern flavours.

Paul Pollaro and Paul Robertson of the University of New Hampshire say their research, published in Frontiers in Conservation Science, shows that urban growth and accompanying deforestation changed the local microclimate where silphium grew.

“You’ll often see the narrative that it [became extinct] because of a mix of over-harvesting and also over-grazing – sheep were very fond of it and it made the meat more valuable,” Pollaro said. “Our argument is that regardless of how much was harvested, if the climate was changing, silphium was going to go extinct anyway.”

Read more: https://www.theguardian.com/world/2022/may/15/caesars-favourite-herb-was-the-viagra-of-ancient-rome-until-climate-change-killed-it-off

The abstract of the study;

Reassessing the Role of Anthropogenic Climate Change in the Extinction of Silphium

Paul Pollaro1* and Paul Robertson2

1College of Life Sciences and Agriculture, University of New Hampshire, Durham, NH, United States

2College of Liberal Arts, University of New Hampshire, Durham, NH, United States

The famed ancient herb, known to the Romans as silphium (Greek silphion), is widely regarded as the first recorded instance of human-induced species extinction. Modern scholars have largely credited direct exploitation (e.g., over-harvesting; over-grazing) as the primary cause of silphium’s extinction, due to an overwhelming demand for the plant in ancient times. Recent research has revealed strict cold-stratification requirements for the germination of silphium’s closest living relatives, revealing the likelihood that silphium shared these same germination requirements. Documented environmental changes in ancient Cyrenaica (e.g., widespread deforestation; cropland expansion) likely resulted in accelerated rates of desertification throughout the region as well as the direct disturbance of silphium’s habitat, effectively eliminating the necessary conditions for silphium’s successful germination and growth within its native range. Contrary to previous conclusions, this evidence suggests that anthropogenic environmental change was instead the dominant factor in silphium’s extinction, marking silphium as the first recorded instance of human-induced climate-based extinction.

Read more: https://www.frontiersin.org/articles/10.3389/fcosc.2021.785962/full

The study dismisses the idea that non-anthropogenic factors were a concern;

… On a related note, the clear lack of evidence for non-anthropogenic ecological drivers of extinction in the ancient literary record is elevated in its significance by our knowledge of silphium’s immense value; that is to say such factors (predatory, pathogenic, or otherwise) would have been highly notable to our ancient sources and thus the absence of related evidence strongly suggests that none were of any major concern. …

Read more: Same link as above

But one thing surprisingly not delved into was the Northern African drying. There is strong evidence that Northern Africa and the Arabian Peninsula experiences alternating wet and dry periods.

Green Sahara: African Humid Periods Paced by Earth’s Orbital Changes

By: Peter B. deMenocal & Jessica E. Tierney © 2012 Nature Education 

Citation: deMenocal, P. B. & Tierney, J. E. (2012) Green Sahara: African Humid Periods Paced by Earth’s Orbital Changes. Nature Education Knowledge3(10):12

Paleoclimate and archaeological evidence tells us that, 11,000-5,000 years ago, the Earth’s slow orbital ‘wobble’ transformed today’s Sahara desert to a land covered with vegetation and lakes.

Although the African paleoclimate records shown in Figures 2 and 3 document a continental-wide pervasiveness of the African Humid Period, the transitions into and out of the AHP may not have been synchronous across all of North Africa (Hoelzmann et al., 2002; Kuper and Kröpelin, 2006), nor were they likely uniformly abrupt (e.g. Figure 3d and e) everywhere. For example, a pollen record of paleovegetation change in the eastern Sahara, extracted from a sediment core from Lake Yoa in northern Chad, documents a gradual end of humid conditions between 5–3 ka BP (Kröpelin et al., 2008). Also, transects of paleohydrological and paleoecological data from the eastern Sahara indicate that the transition out of the humid period was time-transgressive, with dry conditions established earlier in the north (Egypt) and later in the south (Sudan and East Africa; Hoelzmann et al., 2002; Kuper and Kröpelin, 2006). 

Read more: https://www.nature.com/scitable/knowledge/library/green-sahara-african-humid-periods-paced-by-82884405/

Libya, where the Silphium herb grew, was very much a part of the great drying.

I’m not denying that deforestation played a part, and over harvesting of this valuable herb would have played a big part in the eventual extinction – over harvesting could have masked scarcity, leading to Roman writers of the time overlooking the rapidly growing risk of extinction.

But dumping the blame on anthropogenic causes without giving significant weight to the much larger natural regional forcing, which must have brought plants which rely on damp conditions to the very brink of survival, seems to be ignoring the obvious.

via Watts Up With That?

https://ift.tt/QL8AheZ

May 16, 2022 at 12:55AM

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s