The plants that founded Western pharmacy, mapped then and now
What we stand to lose, and where to save it.
Dioscorides compiled De Materia Medica in the 1st century CE; it shaped European pharmacy for more than 1,500 years. Many of its plants still grow wild in Greece. We model where 32 of them live today, where they could survive in 2050, and where they could be cultivated instead.
- Species modelled
- 32
- Climate futures
- 2 scenarios × 3 climate models
- Lose wild habitat by 2050
- 11 of 32 · all 3 models agree
- Candidate farmland by 2050
- 16 plants · outside Natura 2000
- Historical identifications
- 115 claims since 1530
Which plant Dioscorides meant moves 5 of 32 plants in or out of the top 10
9 of our plants have disputed identifications. We modelled all 19 rival species that the cited scholarship names for them (another 16 have too few records in Greece to model) with the same data, models and climate futures, and re-ranked all 32 plants once per alternative. Depending on the identification, Stinging nettle enters the top 10 and St John's wort, Hyssop, Prickly juniper (eastern) and Cretan mountain tea drop out. For 4 of the 9 disputed plants, their own place in the top 10 depends on the identification. Modelled as Paeonia peregrina, Wild peonies of Greece would rank first, above dittany (published rank 5; that model rests on 69 records).
See every rival identification, with its sourceCretan dittany ranks first and has almost nowhere to be grown instead
Its identification is certain, it grows only in Greece, and under moderate emissions its climate range changes by −58% by 2050 (−24 to −81% across 3 climate models). Candidate farmland for it in 2050: 17 km² (0–210 km²). Its model only just beats a distance-only baseline (AUC 0.961 vs 0.959), so treat the map as a hypothesis.
For judges: a 60-second path
- 1. The findingWhich plant Dioscorides meant changes the ranking.
- 2. Cretan dittanyRank 1, its range, its single farmland cell.
- 3. IdentificationEvery rival species, re-ranked with sources.
- 4. MethodsData, validation, baseline, limits.
A split future, not a uniform decline
Under moderate emissions, 11 of 32 plants lose wild habitat by 2050 in every climate model we ran, while 21 keep or gain it (median change across all plants +16%). The losers are concentrated at the top of the risk ranking (10 of the top 10), and they include plants Greece is known for: Cretan dittany, Hyssop, Marsh mallow, Cretan mountain tea. Averages hide this, so we report each plant, with its spread across models.
Most at risk
Top 5 of 32 by combined risk score. Ranks are uncertain too; the interval comes from 1,000 random weightings.
- No. 1 (1–23)HighδίκταμνονCretan dittanyOriganum dictamnusCertainGreek endemic
- Risk score
- 0.62 (0.48–0.71)
- Range change, 2050 moderate
- −58% (−24 to −81%)
- No. 2 (1–3)ElevatedὕσσωποςHyssopHyssopus officinalisDisputedLow-confidence model
- Risk score
- 0.57 (0.52–0.59)
- Range change, 2050 moderate
- −69% (−57 to −74%)
- No. 3 (2–10)ElevatedἀλθαίαMarsh mallowAlthaea officinalisProbable
- Risk score
- 0.54 (0.51–0.56)
- Range change, 2050 moderate
- −62% (−55 to −68%)
- No. 4 (3–7)ElevatedσιδηρῖτιςCretan mountain tea / ironwortSideritis syriacaDisputedLow-confidence model
- Risk score
- 0.49 (0.42–0.50)
- Range change, 2050 moderate
- −50% (−32 to −52%)
- No. 5 (1–7)ElevatedγλυκυσίδηWild peonies of GreecePaeonia L.Disputed
- Risk score
- 0.44 (0.41–0.51)
- Range change, 2050 moderate
- −24% (−17 to −41%)
Cretan dittany, now and in 2050
Origanum dictamnus · projected range change under moderate emissions −58% (−24 to −81%)
Ways in
- Decide
Action plan
Which plants to protect, which to cultivate, and a grower finder that lists what a farmer could plant in any ~10 km cell by 2050.
Open action plan - Then
Names through time
115 dated identifications since 1530: who matched each Greek name to which modern plant, and where scholars still disagree.
Open names through time - Test us
Risk weight lab
A ranking is a value judgement. Re-weigh climate, endemism, status and harvest, and watch the ranking move live.
Open risk weight lab - Explore
Map explorer
Combined risk on a 10 km grid, cultivation hotspots and Natura 2000; select any area to list its plants.
Open map explorer
Thirty-two plants, from Dioscorides' text to a 2050 map
Sort by risk, filter by endemism or identification confidence, and open any plant for its source chapter, model and caveats.