From species to cultivar and backwards

Species in Biology - Novitates Theriologicae ◽

10.53452/nt1231 ◽

2021 ◽

pp. 196-202

Author(s):

Andrey Yena

Keyword(s):

Natural Selection ◽

Selective Breeding ◽

Cultural Objects

When one describes some plants, there are cases when natural selection produces cultivars, and the products of selective breeding appear to be species. The majority of specialists in fundamental and applied botany do not pay respective attention to this problem. Meanwhile, despite the formal following of the rules of respective Codes, there is a disregard to fundamental tenets of philosophy and mixing of natural and cultural objects. There is need to develop mechanisms that would prevent the conversion of species into cultivars and vice versa. The issue is considered on nomenclatural examples of taxa and culta of the genus Hedera.

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The effect of the environment on phenotypic variability

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1958.0062 ◽

1958 ◽

Vol 149 (935) ◽

pp. 192-203 ◽

Cited By ~ 7

Keyword(s):

Body Weight ◽

Natural Selection ◽

Phenotypic Variation ◽

Selective Breeding ◽

Environmental Influence ◽

Phenotypic Variability ◽

Biometrical Genetics ◽

Hot Environment

Mice were raised from birth to 4 weeks of age in three climatic chambers maintained at temperatures of 28 °C (‘hot’), 21 °C (‘temperate’) and 5 °C (‘cold’). Their individual weights were recorded at weeks 1, 2, 3 and 4, and analyzed for the sexes separately. Our object was to test the hypothesis of ‘environmental destabilization’, according to which the mice raised in the extreme climates would be expected to be more variable than those raised in the temperate conditions to which the species has been adapted by natural selection. In overall variability the mice raised in the extreme climates greatly exceeded the temperate level. This was partly due to an exacerbation, particularly in the cold, of the normal tendency for body weight to vary inversely with the number of mice in the litter. But it was in part due to an increase of variability among litter-mates: this effect, which we take to be a genuine example of ‘destabilization’, was more pronounced in the hot environment than in the cold. Members of large litters varied more among themselves than members of small litters. All the effects described above were, in general, more pronounced in the female than in the male The possibility, suggested by this work, that phenotypic variation may be affected by the level of a uniformly acting environmental influence during development has implications for biometrical genetics, selective breeding and evolution.

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