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This paper reviews the ongoing failure of hybrid transgenic Bt (Bacillus thuringiensis) cotton unique to India. The underlying cause for this failure is the high cost of hybrid seed that imposes a suboptimal long-season low plant density system that limits yield potential and has associated elevated levels of late-season pests. Indian hybrid Bt cotton production is further complicated by the development of resistance to Bt toxins in the key pest, the native pink bollworm (Pectinophora gossypiella Saunders, PBW), resulting in increased insecticide use that induces ecological disruption and outbreaks of highly destructive secondary pests. Rainfed cotton production uncertainty is further exacerbated by the variable monsoon rains. While hybrid cotton produces fertile seed, the resulting plant phenotypes are highly variable preventing farmers from replanting saved seed, forcing them to buy seed yearly (i.e., market capture), and effectively protecting industry Intellectual Property Rights (IPRs). The lessons gained from the ongoing market failure of hybrid Bt cotton in India are of utmost importance to its proposed introduction to Africa where, similar to India, cotton is grown mainly in poor rainfed smallholder family farms, and hence similar private–corporate conflicts of interest will occur. Holistic field agroecological studies and weather-driven mechanistic analyses are suggested to help foresee ecological and economic challenges in cotton production in Africa. High-density short-season (HD-SS) non-hybrid non-genetically modified irrigated and rainfed cottons are viable alternatives for India that can potentially produce double the yields of the current low-density hybrid system. [ABSTRACT FROM AUTHOR]

Aim: During the Plio‐Pleistocene, glacial cycles shaped Northern Hemisphere species' distributions causing range contractions followed by interglacial expansions. In migratory bird species, climatic changes could result in a rapid reshaping of their ranges and/or migratory behaviour, given their dispersal capacity. In this context, it has been suggested that long‐distance North American migratory species could have lost their migratory condition during cold glacial periods, regaining it later in warmer periods. Here, we explored this hypothesis for extant Eurasian‐African migratory bird species. Location: Eurasia and Africa. Taxon: Migratory birds. Methods: We used Species Distribution Models (SDMs) to infer the present and Last Glacial Maximum (LGM) potential distribution of 81 Trans‐Saharan migratory bird species, and reviewed the available bird fossil record for the Plio‐Pleistocene covering Eurasia and Africa. Results: SDMs predicted a reduction of the northern edges of the breeding ranges during the LGM compared to the present. However, the current wintering ranges were somewhat similar in the Pleistocene, with the Saharan desert belt gap being always present through time, not overlapping with their breeding ranges. The fossil record also supports the persistence of migration during the Pleistocene. Main conclusions: The palaeo‐distributions and absence of medullary bone in Pleistocene fossils from wintering Euro‐African migratory species confirm that they were migratory, providing independent support for our models. The hypothesis of the loss of migratory behaviour in these species during the Pleistocene is not supported. Furthermore, the differences in migratory species from Eurasia‐Africa and the Americas can be influenced by geographical differences, the persistence of the Mediterranean basin as climatically suitable area during glaciations and the existence of the Saharan belt. [ABSTRACT FROM AUTHOR]