5/4/2023 0 Comments Parallel evolutionDevelopment of annuals at different elevations in East India, Northern Southeast Asia and West China was enhanced by alternating periods of drought and variations in temperature during Neo-thermal age about 10,000–15,000 years ago ( Whyte, 1972). Domestication of wild rices probably started about 9000 years ago. All these wild relatives of rices cross with cultivated rice under natural conditions in rice growing countries, which might have produced the hybrid swarms in the field. In monsoonal Asia, the perennial types grow in deep swamps, which retain moisture throughout the year while the annual types occur in temporary marshes, which are parched in dry season. In other words, the perennial types may have higher out-crossing rates than annual types and also have lower seed productivity. ![]() rufipogon is distributed from Pakistan to China and then to Indonesia and its populations vary between perennial and annual types of rice, which may differ markedly in life history traits ( Oka, 1988). ![]() breviligulata, which in turn evolved from perennial O. glaberrima was domesticated for annual O. Annual types, also given a specific name of O. rufipogon (Asian common wild rice), which shows a range of variation from perennial to annual types. glaberrima are thought to be an example of parallel evolution in crop plants. Swarnam, in Biodiversity and Climate Change Adaptation in Tropical Islands, 2018 6.1 Wild Progenitors of Cultivated Rice The reduction of the swim bladder is more widespread, reduced in some members of three families and totally lost in two families. ![]() Somewhat more widespread is scale loss in some species of four families of teleost fish. The clear paedomorphosis seen in the Urodele amphibia and the pseudophysogastry of beetles of the subfamilies Catopocerinae and Cholevinae of the family Leiodidae, and the subfamily Trechinae of the family Carabidae ( Fig. Another taxonomically limited troglomorphy is the development of a ridge on the ventral surface of the thorax in the tribe Leptodirini of the beetle family Leiodidae. Many troglomorphic changes are limited to one order or even to one or a few families, including the foot modifications seen in Collembola ( Fig. Troglomorphic changes vary in their generality. Convergent pseudophysogastry in different lineages of cave beetles: (A) Trechinae, Aphaenops pluto (after Vandel, 1964) (B) Cholevinae, Glacicavicola bathysciodes (courtesy Stewart Peck) (C) Bathysciinae, Antroherpon scutulatum (courtesy Pier Mauro Giachino) and (D) Bathsciinae, Leptodirus hohenwarti.
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