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Full-Text Articles in Life Sciences
Enzymological And Radiotracer Studies Of Lipid Metabolism In The Flight-Capable And Flightless Morphs Of The Wing-Polymorphic Cricket, Gryllus Firmus, Z. Zhao, Anthony J. Zera
Enzymological And Radiotracer Studies Of Lipid Metabolism In The Flight-Capable And Flightless Morphs Of The Wing-Polymorphic Cricket, Gryllus Firmus, Z. Zhao, Anthony J. Zera
Anthony Zera Publications
The flight-capable morph of the wing-polymorphic cricket, Gryllus firmus, exhibited significantly higher activities of each of five lipogenic enzymes compared with the obligately flightless morph on a standard and a high-carbohydrate diet during early adulthood. Similarly, the rate of incorporation of [14C]-acetate into total lipid was higher in the flight-capable morph during this time. By contrast, activities of lipogenic enzymes and rates of lipid biosynthesis, in general, did not differ between morphs on a low nutrient diet during early adulthood. Differences in lipid biosynthesis account for previously documented differences in lipid reserves between morphs on some, but …
The Metabolic Basis Of Life History Variation: Genetic And Phenotypic Differences In Lipid Reserves Among Life History Morphs Of The Wing-Polymorphic Cricket, Gryllus Firmus, Anthony J. Zera, A. Larsen
The Metabolic Basis Of Life History Variation: Genetic And Phenotypic Differences In Lipid Reserves Among Life History Morphs Of The Wing-Polymorphic Cricket, Gryllus Firmus, Anthony J. Zera, A. Larsen
Anthony Zera Publications
The flight-capable morph of the wing-polymorphic cricket, Gryllus firmus, accumulated a substantially greater quantity of total lipid and triglyceride, compared with the obligately flightless morph, during the first five days of adulthood. Increased lipid accumulation in the flight-capable morph was genetically based, and was produced when ovarian growth is substantially reduced in that morph. Temporal changes in lipid levels suggest that the higher triglyceride reserves in the flight-capable morph fed a high-nutrient diet were produced by elevated lipid biosynthesis. By contrast, on a low-nutrient or high carbohydrate diet, increased lipid levels in the flight-capable morph appeared to result primarily …
The Physiology Of Life History Trade-Offs In Animals, Anthony J. Zera, Lawrence G. Harshman
The Physiology Of Life History Trade-Offs In Animals, Anthony J. Zera, Lawrence G. Harshman
Anthony Zera Publications
The functional causes of life history trade-offs have been a topic of interest to evolutionary biologists for over six decades. Our review of life history trade-offs discusses conceptual issues associated with physiological aspects of trade-offs, and it describes recent advances on this topic. We focus on studies of four model systems: wing polymorphic insects, Drosophila, lizards, and birds. The most significant recent advances have been: (a) incorporation of genetics in physiological studies of trade-offs, (b) integration of investigations of nutrient input with nutrient allocation, (c) development of more sophisticated models of resource acquisition and allocation, (d) a shift to more …
Genetic And Diurnal Variation In The Juvenile Hormone Titer In A Wing-Polymorphic Cricket: Implications For The Evolution Of Life Histories And Dispersal, Anthony J. Zera, Gretchen Cisper
Genetic And Diurnal Variation In The Juvenile Hormone Titer In A Wing-Polymorphic Cricket: Implications For The Evolution Of Life Histories And Dispersal, Anthony J. Zera, Gretchen Cisper
Anthony Zera Publications
The wing-polymorphic cricket, Gryllus firmus, contains (1) a flight-capable morph (LWf) with long wings and functional flight muscles, (2) a flightless morph with reduced wings and underdeveloped flight muscles (SW), and (3) a flightless morph with histolyzed flight muscles but with fully developed wings (LWh). The LWf morph differed genetically from the SW morph and phenotypically from the LWh morph in the size of flight muscles, ovarian growth during the first week of adulthood, and the hemolymph titer of juvenile hormone (JH). This is the first study to document that phenotypes that differ …
The Endocrine-Genetic Basis Of Life-History Variation: The Relationship Between The Ecdysteroid Titer And Morph-Specific Reproduction In The Wing-Polymorphic Cricket Gryllus Firmus, Anthony J. Zera, Justin Bottsford
The Endocrine-Genetic Basis Of Life-History Variation: The Relationship Between The Ecdysteroid Titer And Morph-Specific Reproduction In The Wing-Polymorphic Cricket Gryllus Firmus, Anthony J. Zera, Justin Bottsford
Anthony Zera Publications
The hormonal basis of variation in life-history traits is a poorly studied topic in life-history evolution. An important step in identifying the endocrine-genetic causes of life-history variation is documenting statistical and functional associations between hormone titers and genotypes/phenotypes that vary in life-history traits. To this end, we compared the blood ecdysteroid titer and the mass of the ovaries during the first week of adulthood among a flight-capable morph and two fl ightless morphs of the wing-polymorphic cricket Gryllus firmus. Ecdysteroids are a group of structurally related hormones that regulate many important aspects of reproduction in insects. Both the ecdysteroid …