- Graph-based pan-genome reveals structural variations associated with agronomic traits in mung bean. Pan-genome captures extensive structural variation missed by a single reference genome, providing new targets for mung bean improvement.
- Wild genes to the rescue: high-throughput genomics reveals the wild source of broomrape resistance in sunflower. Combining high-throughput root phenotyping with genomics identifies wild introgressions underlying broomrape resistance in sunflower and exposes valuable adaptive variation for breeding.
- Genomic insights into the local adaptation of spontaneous olive trees in the Mediterranean Basin highlight the need for conservation planning in the face of global change. Genomics of wild West Mediterranean olive trees reveals patterns of local adaptation across temperature and rainfall gradients that it will be important to conserve as climates change.
- Genetic regulation of major immunogenic protein accumulation in peanut seeds. Genomics provides targets for breeding peanuts with reduced allergenicity.
- Genomic elucidation of hybridization between Liberica and excelsa coffee and its implications for coffee crop development. Genomics confirms that Liberica and excelsa coffee readily hybridize and produce fertile, genetically diverse offspring with intermediate agronomic traits, a possible source of diversity to broaden coffee’s climate resilience.
- Simple sequence repeat (SSR) marker-based genetic diversity and population structure of large-leaf tea germplasm across four major tea-producing regions of Yunnan, China. Genomics of Yunnan’s large-leaf tea germplasm finds substantial genetic diversity but remarkably little regional differentiation, showing that seed propagation, natural crossing and human movement have maintained genetic connectivity across tea-growing regions.
- Measuring maternal line selection driven by differential survival in ex situ collections for plant conservation. A new method distinguishes random mortality from selection among maternal lines in ex situ collections, offering conservationists a way to detect whether plant deaths are systematically eroding the genetic variation they are trying to preserve. And no genomics involved.
A Babel of agrobiodiversity
“The rise and fall of language diversity through the Holocene” by Blasi, Hamilton, Gray & Bowern, published in Science last month, does something I really love. It complicates a standard narrative.
The received story of language diversity is that it has been declining steadily for centuries, largely driven by colonialism and globalization. But direct evidence is scarce and recent: writing only reliably takes us back about 6,000 years. So the team combined ethnographic data from 171 hunter-gatherer and fisher societies, paleodemographic estimates of global population, and statistical and social-computational modelling to reconstruct plausible trajectories of global language diversity over the 12,000 years of the Holocene, which began after the last major ice age, triggering the birth of agriculture.
At the beginning of this period, they estimate there were roughly 4,500–6,200 languages. That’s actually fewer than the roughly 7,500 languages spoken today. Language diversity then increased through most of the Holocene, driven by the population growth engendered by agriculture, reaching a peak between about 1,000 and 3,000 years ago, when the models suggest that tens of thousands of languages may have existed. That’s an order of magnitude more than today.
Then came a major collapse. The authors argue that the decline in linguistic diversity began with the expansion of large states and empires, long before European colonialism. Expanding populations and their languages, cultures and institutions displaced smaller ones. Today’s languages are therefore “survivors of a massive and highly selective historical bottleneck.” They persist because the populations speaking them expanded. Extinction, the authors argue, has shaped linguistic and cultural diversity far more — and for longer — than we have appreciated.
Now, there are obvious caveats. The authors are modelling linguistic diversity, not measuring it. Their estimates depend on heroic assumptions about early ethnolinguistic group sizes, global population and the relationship between population and language number. Regional histories could have been very different, and the model can’t reconstruct individual episodes of extinction caused by war, disease or environmental change.
But the paper provides a provocative template for thinking about diversity more generally. It suggests that population growth can initially generate diversity; but expanding societies can subsequently erase it through homogenization.
And that makes me wonder about agricultural biodiversity. You saw that coming, I’m sure.
I’m not suggesting that crop diversity followed the same pattern as language diversity through the Holocene. We simply don’t have the evidence to say that, though it’s an intriguing thought. But could we borrow the methodology? Could we reconstruct plausible trajectories of crop or agricultural-system diversity from fragmentary archaeological, ethnobotanical, genetic and demographic evidence?
Rather than assuming that agricultural diversity was vast and stable in the distant past, happy in its Vavilovian centres, and has been declining recently, perhaps we might end up complicating the familiar genetic erosion narrative too. That would be worthwhile. And fun.
Brainfood: Avocado history, Brazil commuity seedbanks, Citizen science, Agroecology double, Indigenous knowledge, Turkish seeds, Swiss biodiversity
- Ethnobotanical and genetic assessments of Central American avocado landraces reveal novel sources of biodiversity and ancient migration patterns. DNA from landraces, and interviews with farmers, show that people transported and cultivated avocados across the Americas long before European contact, with landraces from lowland Nicaragua and Honduras in particular showing evidence of ancient migration from South America.
- The Circle of Seeds: An Ethnography of Seed Guardianship and the Making of Agroecological Futures in Paraná, Brazil. Community seed banks depend on relationships of care, reciprocity and collective labour, especially among women farmers, and not just on knowing how to store seeds properly. Though that helps, clearly.
- iNaturalist as a Tool to Improve Agroecological Biodiversity Knowledge: An Ecuadorian Case Study. A citizen science platform can strengthen agroecological biodiversity knowledge, but more efforts are needed to engage farmers.
- Are agroecological practices pro-poor? Evidence from smallholder farms in Zimbabwe. Farmers using agroecological practices were generally wealthier and their farms were more diverse in crop and livestock species, but the association between the use of improved practices and diet outcomes was inconsistent.
- Regenerative agriculture for dietary diversity and food security in Zambia. Agroecological practices were positively correlated with improved dietary quality and food security, including (though not exclusively) through farm production diversity. No word on the wealth of the farmers involved.
- Indigenous Peoples’ knowledge systems and practices for climate survival. Indigenous knowledge systems, including of farmers, offer tested approaches to climate adaptation and resilience that warrant a central place in responses to environmental change.
- Guardians of Agricultural Biodiversity: Farmer Perceptions and Sustainability of Local Seed Varieties in Turkish Highlands. Farmers continue to maintain local seed varieties, driven as much by social, cultural and market considerations as by agronomic performance. But they need support.
- Religion, spirituality and faith of Swiss farmers in relation to biodiversity-linked farming behaviour. Farmers’ religious and spiritual values can shape biodiversity-friendly management decisions, showing personal belief systems are important in conservation. Even in Switzerland.
Nibbles: Museum of Cider, Aport apple, Rattan genebank, Sri Lanka rice, Saudi coffee landscapes
- In the UK, Herefordshire’s Museum of Cider is picking up national recognition for its genebank of heritage apple trees. The BBC’s canonical autumnal apple story comes a little early this year.
- Speaking of iconic apples, Kazakhstan is scaling up efforts to bring back the Aport, the giant heirloom that once made Almaty famous. No word of museums, though. Or cider.
- Over in the Philippines, Department of Environment and Natural Resources is beefing up its rattan genebank to keep pace with demand, with forest stewards in Bukidnon planting seedlings to match. Furniture makers need genebanks as much as cider makers.
- Sri Lanka’s pre-Green Revolution heirloom rice varieties, purana haal, are being eyed for their resilience and disease-management potential. Good thing they’re in the national genebank.
- Saudi Arabia’s Jazan terraced coffee farms are turning into rural and ecotourism hotspots, proving not all agrobiodiversity needs to be in a genebank to survive. But it helps.
Nibbles: Tigray grapes, Latin American opportunity crops, Hawaii & Cayman coconuts, North Macedonian collecting, South Korea seed vault, Eswatini seed hub, Expensive healthy diets
- A North Macedonian professor’s 15-year rescue mission for landraces and crops surviving only in remote villages. Why bother? Stay tuned…
- Ancient grapevines in Tigray represent a unique genetic lineage with potential value for breeding varieties adapted to dryland conditions.
- Hawai’i Public Radio checks in on Maui’s coconut genebank. Useful to breed varieties adapted to really wet conditions, presumably.
- The Cayman Islands are also hoarding coconuts, along with lots of tasty fruits.
- A USD 400,000 boost from Taiwan for the Eswatini national genebank. Indigenous vegetables get much-needed love.
- A regional survey of 25 orphan crops across 13 Latin American countries finds quinoa and amaranth well-catalogued, but characterization budgets are the real bottleneck. Collecting and conserving in genebanks is great, but not enough.
- South Korea puts 330,000 seed accessions under “double lock”, hedging against both climate change and war. Conserving in one place is not enough.
- FAO warns that nearly a third of the world can’t afford the USD 4.28 a day that a healthy diet costs — nearly three billion people, and rising. That’s why we need al the above, I guess.