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131.
MARTIN J. JONES MATTHEW S. SULLIVAN STUART J. MARSDEN MARK D. LINSLEY 《Biological journal of the Linnean Society. Linnean Society of London》2001,73(1):65-79
Size of distributional range, position in the range, body size and diet are some of the ecological traits that may correlate with local abundance. Evolutionary phenomena such as taxon cycles, acting over much greater time periods, may also influence abundance and promote species extinction. This paper assesses which of a wide range of ecological and historic traits best predict the variation in abundance of tropical forest birds on Sumba and Buru islands in Wallacea (Indonesia). In addition we seek to determine which traits predict species' ability to adapt to secondary or logged forest. The most important correlates of both abundance and ability to transfer were those related to the evolutionary history of the species within the Wallacean Archipelago and not the traits that were more directly related to species ecology. These relationships are maintained when allowance is made for phylogenetic relationships. Our interpretation of the results is that recent colonists to an island are initially rare in the indigenous forest habitat but concomitant with an adaptation to local conditions they gradually become more abundant and taxonomically distinct from other populations of the same species. These results apparently contradict the taxon cycle hypothesis but this may be a result of our focus on indigenous forest habitats rather than on a wider range dominated by anthropogenic ones. 相似文献
132.
Usdin K; Chevret P; Catzeflis FM; Verona R; Furano AV 《Molecular biology and evolution》1995,12(1):73-82
The single most difficult problem in phylogenetic analysis is deciding
whether a shared taxonomic character is due to common ancestry or one that
appeared independently due to convergence, parallelism, or reversion to an
ancestral state. Mammalian L1 retrotransposons undergo periodic
amplifications in which multiple copies of the elements are interspersed in
the genome. Because these elements apparently are transmitted only by
inheritance and are retained in the genome, a shared L1 amplification event
can only be an inherited ancestral character. We propose that L1
amplification events can be an excellent tool for analyzing mammalian
evolution and demonstrate here how we addressed several refractory problems
in rodent systematics using L1 DNA as a taxonomic character.
相似文献
133.
Use of lichen secondary metabolites as antifeedants to protect higher plants from damage caused by slug feeding 总被引:1,自引:0,他引:1
Extracts of 15 species of lichen were tested for antifeedant properties against the field slug Deroceras reticulation (Müller) (Mollusca: Pulmonata). All but three showed some activity and two of these were from endolithic species. The most effective extract was from Letharia vulpina. The major active compound from this species, vulpinic acid, was tested for dose response, applied as a foliar spray to turnip plants and as a dressing to wheat seeds in laboratory experiments. It provided effective protection against slug feeding under these conditions. 相似文献
134.
JENNY MARTIN 《Austral ecology》2005,30(1):128-129
135.
A partially sterile condition of the tomato Tiny Tim resultsin smaller-than-normal pollen, high pollen abortion, reducedfruit and seed set, and small seeds of low viability. Pollenabortion is initiated after break-up of the tetrads. In crosses.tothe fertile variety Atom, reduced fruit and seed set is partiallydominant, and apparently-multigenically controlled. Seed sizeis influenced by both cytoplasmic and genic factors. Such partialsterility is suspected to be common, and could result in disturbedsegregation ratios of genes. 相似文献
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