The Domestication Syndrome Genes Responsible for the Major Changes in Plant Form in the Triticeae Crops

The process of crop domestication began 10,000 years ago in the transition of early humans from hunter/gatherers to pastoralists/farmers. Recent research has revealed the identity of some of the main genes responsible for domestication. Two of the major domestication events in barley were (i) the failure of the spike to disarticulate and (ii) the six-rowed spike. The former mutation increased grain yield by preventing grain loss after maturity, while the latter resulted in an up to 3-fold increase in yield potential. Here we provide an overview of the disarticulation systems and inflorescence characteristics, along with the genes underlying these traits, occurring in the Triticeae tribe

Identifying ancient water availability through phytolith analysis: An experimental approach.

Water management was critical to the development of complex societies but such systems are often difficult, if not impossible, to recognise in the archaeological record, particularly in prehistoric communities when water management began. This is because early irrigation systems are likely to have been ephemeral and as such would no longer be visible in the archaeological record. We conducted a three year crop growing experiment in Jordan to test the hypothesis that phytoliths (opaline silica bodies formed in plants) can be used to detect the level of past water availability and hence be used as a source of information for inferring past water management. Over a three year period we grew native land races of six-row barley (Hordeum vulgare) and durum wheat (Triticum durum) at three crop growing stations in Jordan with the crops being subjected to different irrigation regimes. Seeds were sown in the autumn and the crops harvested in the spring. The plants were then exported to the University of Reading for phytolith processing. Our results show that while there were unknown factors that influenced phytolith production between years, at the higher levels, the ratio of ‘fixed’ form phytoliths (those formed as a result of genetically determined Silicon uptake) to ‘sensitive’ form phytoliths (those whose Silicon uptake is environmentally controlled) can be used to assess past water availability. Our study is the first large scale experimental project to test this method and take into account multiple variables that can affect phytolith production such as soil composition and chemistry, location, climate and evapotranspiration rates. Results from the cereals grown at two of the crop growing stations, Deir ‘Alla and Ramtha, which received between 100 millimetres and 250 millimetres rainfall per annum, demonstrate that if the ratio of fixed to sensitive phytolith forms is >1, the level of past water availability can be predicted with 80% confidence. Results from the crops grown at the other growing station, Kherbet as-Samra, which received less than 100 millimetres of rainfall per year show that if the ratio of fixed to sensitive forms is >0.5, the level of past water availability can be predicted with 99% confidence. This demonstrates that phytolith analysis can be used as a method to identify past water availability

Population Density of Free-Roaming Cats in Relation to Feeding Stations on Hayden Island

Free-roaming cats have a devastating impact on wildlife populations with stray/feral cats being the most problematic. In some areas, community members provide these cats with food, water, and shelter often in conjunction with a trap, neuter, return (TNR) program. Regardless of TNR, some studies suggest that feeding stray cats allows them to live longer which increases their impact on local wildlife populations. In contrast, we documented that a constantly available food source correlated to a higher density of cats in urban areas with less wildlife value and where they can be integrated into a TNR program. The Hayden Island Cat Project has utilized TNR, cat adoption, and outreach to humanely reduce the free-roaming cat population since 2014. Many residents on the island provide feeding stations for the cats and actively participate in the TNR program. To determine how feeding might affect cat spatial distribution, camera traps were placed at 20 different stations in urban and natural areas on Hayden island. Additional data from the annual road cat count was used to compare cat density relative to feeding stations utilizing ArcGIS. Coordinates of feeding stations based on a resident survey were overlaid onto the cat location coordinates and a clear density correlation appeared. Camera traps reinforced these findings whereby only a single cat was photographed in the natural area. These results demonstrate that feeding free-roaming cats combined with management actions aimed at humanely reducing cat populations, may lessen the impact on wildlife and be ethically acceptable to local residents

Density of Free-Roaming Cats Related to Feeding Stations on Hayden Island, Oregon

Free-roaming cats have a devastating impact on wildlife populations with stray/feral cats being the most problematic. In some areas, community members provide these cats with food, water, and shelter often in conjunction with a trap, neuter, return (TNR) program. Hayden Island located north of Portland, Oregon is home to a managed colony of feral and stray cats. Some island residents provide feeding stations for the cats and actively participate in population management. To determine how feeding stations might affect cat spatial distribution, camera traps were placed at 19 different stations in urban and natural areas on Hayden island. Additional annual road cat count data was used to compare cat density relative to feeding stations utilizing ArcGIS. When individual cat locations were overlapped with the heat map for feeding stations, greater cat densities in proximity to feeding stations were observed. These results were supported by a density analysis of cats and feeding stations as well as the camera trap results as only a single cat was photographed in the natural area. We documented that a reliable food source was connected to a higher density of cats in urban areas with less wildlife value and where they can be more easily monitored

Preferences of Cavity Nesting Bees in Portland

Little is known about the diverse life histories of our many native bee species, although many are threatened by habitat loss through urbanization. For example, few studies have examined the role of nest height or cavity size in attracting our lesser known native cavity-nesting bees. To remedy this paucity of data, we set up cavity nest boxes across fourteen locations in the greater Portland area and erected wooden posts with nest blocks at 3 different heights (0.5, 1.5, and 2.3 meters). To accommodate a diversity of bee species, cavity diameters ranged in size from 3.0 to 10.0 mm. From these nests, we collected data to determine nest occupancy, nest diameter size preferences, and percent bee and wasp occurrence rates. The overall nest height occupancy rates greatly varied amongst the fourteen locations, but overall the 2.3 m height had the greatest percent occupancy. Although the bees and wasps from the nests collected in 2019 have not yet emerged we estimate that the nests will yield about 68% bees and 32% wasps. Lastly, the greatest occupancy rates were observed in the two smallest cavity diameters, 3.0 and 4.5 mm. Nesting preference data will be used to better inform residents of greater Portland how best to provide nesting habitat for cavity nesting bees, and the solitary wasps that use similar nesting sites

Barley grain with adhering hulls is controlled by an ERF family transcription factor gene regulating a lipid biosynthesis pathway

In contrast to other cereals, typical barley cultivars have caryopses with adhering hulls at maturity, known as covered (hulled) barley. However, a few barley cultivars are a free-threshing variant called naked (hulless) barley. The covered/naked caryopsis is controlled by a single locus (nud) on chromosome arm 7HL. On the basis of positional cloning, we concluded that an ethylene response factor (ERF) family transcription factor gene controls the covered/naked caryopsis phenotype. This conclusion was validated by (i) fixation of the 17-kb deletion harboring the ERF gene among all 100 naked cultivars studied; (ii) two x-ray-induced nud alleles with a DNA lesion at a different site, each affecting the putative functional motif; and (iii) gene expression strictly localized to the testa. Available results indicate the monophyletic origin of naked barley. The Nud gene has homology to the Arabidopsis WIN1/SHN1 transcription factor gene, whose deduced function is control of a lipid biosynthesis pathway. Staining with a lipophilic dye (Sudan black B) detected a lipid layer on the pericarp epidermis only in covered barley. We infer that, in covered barley, the contact of the caryopsis surface, overlaid with lipids to the inner side of the hull, generates organ adhesion