- A global overview of cassava genetic diversity. The African germplasm is different from the Latin American, but not by that much.
- Genetic variability in landraces populations and the risk to lose genetic variation. The example of landrace ‘Kyperounda’ and its implications for ex situ conservation. Better genetically to conserve landraces as sub-lines. But financially?
- Impact of merging commercial breeding lines on the genetic diversity of Landrace pigs. Above goes for pigs too.
- Selection and Molecular Characterization of Soybeans with High Oleic Acid from Plant Germplasm of Genebank. 3 accessions have interesting variants in the relevant gene.
- Origin and domestication of Cucurbitaceae crops: insights from phylogenies, genomics and archaeology. Lots of different paths to domestication, but all involve loss of flesh bitterness, one way or another.
- Changing Carrot Color: Insertions in DcMYB7 Alter the Regulation of Anthocyanin Biosynthesis and Modification. How the carrot lost its purple.
- A 3,000-year-old Egyptian emmer wheat genome reveals dispersal and domestication history. Most closely resembles modern material from Turkey, Oman and India.
- TeoNAM: A Nested Association Mapping Population for Domestication and Agronomic Trait Analysis in Maize. With added teosinte goodness.
- Adaptive phenotypic divergence in an annual grass differs across biotic contexts. The rhizosphere affects adaptation of teosinte along an altitudinal gradient. We’ll need a Nested Association Mapping Population for that too now, no doubt.
- Population genetics assessment model reveals priority protection of genetic resources in native pig breeds in China. Most breeds have low diversity; Tibetan pigs are an exception.
- A brief history of the forty-five years of the E’AppleBP apple breeding program in Brazil. 27 new varieties seems like pretty good going.
- Testing the Various Pathways Linking Forest Cover to Dietary Diversity in Tropical Landscapes. Sometimes there’s a direct pathway (e.g., consumption of forest food), sometimes an income pathway (income from forest products used to purchase food from markets), and sometimes an agroecological pathway (forests and trees sustaining farm production). And sometimes there isn’t.
- Evolutionary diversity is associated with wood productivity in Amazonian forests. “…greater phylogenetic diversity translates into higher levels of ecosystem function.” No word on its effect on diets.
- Anatomy and resilience of the global production ecosystem. Plenty of words on its effect on diets.
Wood productivity in Amazonian forests
This complex analysis troubles me. It notes that the: “… variation in wood density being the most important variable in controlling patterns of biomass in these forests”.
The clear implication is that, in some way unspecified, wood density in diverse ecosystems enhances ecosystem functioning. To me, this collates two different evolutionary pathways. One the authors recognise: “Host ranges of most tree pests and pathogens show a clear phylogenetic signal, with co-occurring, closely related plant lineages being more vulnerable to similar natural enemies than distant relatives.” That we already know – going back at least to Gillett, J.B. (1962) Pest pressure, an underestimated factor in evolution. Systematics Association Publications 4, 37-46. [Gillet was once my boss in the East African Herbarium]. Taxonomic diversity is a disease-escape mechanism in an otherwise benign environment (warm, wet, whatever) but has no obvious evolutionary relation to ecosystem function in vegetation.
The second evolutionary pathway is also simply Darwinian, evinced at the level of individual species. Masses of diverse woody Dicot species in a warm, wet environment have the same problem: how to stop their dead biomass (heartwood) – needed for supporting the canopy – from rotting. The otherwise benign environment for growth is exactly non-benign for dead wood – the main component of tropical dicot trees.
The common evolutionary response – recognised by anyone using tropical wood – is to pack the dead wood with anti-rot chemicals. This gives us all those rosewoods, ebonies, purplehearts and the rest coveted by cabinetmakers. Thus the resultant high wood density is a direct evolutionary response of many separate species to rot, rather than the response of the ecosystem to try to function in somehow `better’.
(The recognition of the rottability of Dicot wood also allows us to explain buttresses – which are living sapwood and therefore far less rottable than heartwood. Monocots – palms, bamboos – are all `sapwood’ and therefore less in danger; some dicot mangroves, living in very threatening conditions, produce spare parts in the form of renewable living prop-roots).
The review (70+ authors) concludes that: “In particular, this study provides evidence that evolutionary diversity is weakly, but significantly, related to ecosystem functioning at large scales in natural ecosystems.”
Far simpler to say that in species-diverse wet tropical forests woody species must protect themselves from rot by packing their dense, dead, hardwood with anti-rot chemicals. This has very little (or nothing) to do with the relation between taxonomic diversity and ecosystem functioning.