Plant size, latitude, and phylogeny explain within-population variability in herbivory.

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.

Incidence of Sitophilus oryzae and other stored-product pests on cowpea in local markets in Accra: management strategies employed by retailers.

In recent times, the unusual presence of Sitophilus on cowpea has become an issue in Ghana as it constitutes a threat to food sufficiency and food security; this, by extension, necessitated the execution of this survey to establish the specific identity of the insect and its incidence, on stored cowpea in Ghana and consequently assess the level of awareness of traders and the management strategies employed. Using internal morphological identification techniques, the insect was identified as Sitophilus oryzae with an incidence rate of 12, 22 and 20% as against 50, 41 and 42% incidence rate of Callosobruchus maculatus after 30, 60 and 90 days respectively, of undisturbed storage of cowpea within the marketing systems in Accra, Ghana. Relatively low number of retailers (35.44%, N = 79) was aware of this occurrence, with 91.14% of this employing the energy-demanding and time-consuming sieving techniques as their main control strategies. This paper draws attention to the possible worsening of food insecurity already eminent in Africa for insects are no respecters of international or geo-political boundaries as they can spread to other countries, should this observation be left unchecked.