Investigations into the evolutionary origin of navigation and learning

International Allelopathy Society has redefined Allelopathy as any process involving secondary metabolities produced by plants, algae, bacteria, fungi and viruses that influences the growth and development of agricultural and biological system; a study of the functions of secondary metabolities, their significance in biological organization, their evolutionary origin and elucidation of the mechanisms involving plant-plant, plant-microorganisms, plant-virus, plant-insect, plant-soil-plant interactions.

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The Origin of Workerless Parasites inLeptothorax(S. Str.) (Hymenoptera: Formicidae)

Psyche A Journal of Entomology ◽

10.1155/1995/69812 ◽

1995 ◽

Vol 102 (3-4) ◽

pp. 195-214 ◽

Cited By ~ 5

Author(s):

Jürgen Heinze

Keyword(s):

Chromosome Number ◽

Evolutionary Origin ◽

Social Parasites ◽

Leptothorax Acervorum ◽

Using Data

The evolutionary origin of workerless parasitic ants parasitizing colonies ofLeptothorax(s.str.) is investigated using data on morphology, chromosome number, and allozyme phenotype of both social parasites and their hosts. Of the three previously proposed pathways, the evolution of workerless parasites from guest ants or slave-makers is unlikely, at least according to a phenogram obtained by UPGMA clustering of Nei's similarities based on seven enzymes, lntraspecific evolution of the workerless parasitesDoronomyrmex goesswaldi, D. kutteri, andD. pacisfrom their common host,Leptothorax acervorumcannot be excluded with the present data. The workerless parasiteL. paraxenus, however, clearly differs from its host,L.cf.canadensis, in morphology and biochemistry, and most probably did not evolve from the latter species. It is proposed to synonymizeDoronomyrmexunderLeptothorax(s.str.).

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Selfish Genes, Pleiotropy and the Origin of Recombination

Genetics ◽

10.1093/genetics/149.4.2089 ◽

1998 ◽

Vol 149 (4) ◽

pp. 2089-2097 ◽

Cited By ~ 2

Author(s):

Jody Hey

Keyword(s):

Natural Selection ◽

Simple Model ◽

Computer Simulations ◽

Recombination Rate ◽

Evolutionary Origin ◽

Deleterious Mutations ◽

Beneficial Mutations ◽

Selfish Genes ◽

Simple Interaction

Abstract If multiple linked polymorphisms are under natural selection, then conflicts arise and the efficiency of natural selection is hindered relative to the case of no linkage. This simple interaction between linkage and natural selection creates an opportunity for mutations that raise the level of recombination to increase in frequency and have an enhanced chance of fixation. This important finding by S. Otto and N. Barton means that mutations that raise the recombination rate, but are otherwise neutral, will be selectively favored under fairly general circumstances of multilocus selection and linkage. The effect described by Otto and Barton, which was limited to neutral modifiers, can also be extended to include all modifiers of recombination, both beneficial and deleterious. Computer simulations show that beneficial mutations that also increase recombination have an increased chance of fixation. Similarly, deleterious mutations that also decrease recombination have an increased chance of fixation. The results suggest that a simple model of recombination modifiers, including both neutral and pleiotropic modifiers, is a necessary explanation for the evolutionary origin of recombination.

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