Almost airborne
Article Abstract:
Modern stoneflies offer possible evidence of the evolution of insect wings from the articulated gills of water-dwelling ancestors. Stoneflies of the genus Leuctra are observed to use a form of locomotion that is mechanically halfway between skimming and flying. They are sometimes found to be able to ascend above the water surface and actually fly at an air temperature of 12 degrees centigrade. The stoneflies' different forms of surface locomotion suggest the occurrence of gradual improvements in aerodynamic locomotion while aquatic organisms evolved into flying insects.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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Programmed to stay together
Article Abstract:
Sciara coprophila undergoes programmed chromosome losses that are the basis of its sex determination. The sperm contributes two X chromosomes because of nondisjunction while the oocyte contributes another. This also results in the removal of L chromosomes. Maternal factors control the elimination of the X chromosomes. Sister chromatids fail to separate because the eliminated chromosomes may modulate ubiquitin-mediated proteolysis, topoisomerase II activity or phosphatase activity required during the process of chromatid-separation.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1996
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Chironomid egg masses in Vibrio cholerae
Article Abstract:
Research describing the relationship between cholera and the non-biting midge, Chironomus sp., is presented. In particular it is shown that the egg masses of the midge harbour the bacterium vibrio cholerae.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2001
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