Is speciation no accident?
Article Abstract:
New research has revived interest in the assertion that selection favours an increase in assortive mating in populations which have diverged genetically to the extent that the offspring of within-population matings are healthier than hybrid offspring. It has now been claimed that this process, known as reinforcement, takes place in European flycatchers. Reinforcement seems to be responsible for the fact that male pied flycatchers are brown, rather than black, in populations which have overlapping ranges in central and eastern Europe, with the collared males having extended areas of white. This makes the two forms very distinct.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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Speciation without isolation
Article Abstract:
The barrier preventing sympatric speciation in sexual populations is that mating between divergent ecotypes continually scrambles gene combinations creating intermediate phenotypes in organism. Assortative mating prevents this mixing, but recombination is a barrier to assortative mating. Kondrashov and Kondrashov have presented a model with two variants where mating probability relies on similar market traits, or the match between male trait and female preferences. Dieckmann and Doebeli's model determines mating probability by either ecological trait or a marker trait.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
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The complete genome sequence of the Gram-positive bacterium Bacillus subtilis
Article Abstract:
The complete genome sequence of the Gram-positive bacterium Bacillus subtilis consists of 4,214,810 base pairs and 4,100 protein-coding genes. The genetic sequence is illustrated, together with a distribution of A and T-rich islands and coding nucleotides. Much of the dinucleotide bias has been observed in previous prokaryote research. Further research into the evolutionary development of gram-positive and gram-negative bacteria is possible.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
User Contributions:
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