|Appears in Collections:||Biological and Environmental Sciences Journal Articles|
|Peer Review Status:||Refereed|
|Title:||Determination of larval melanization in the moth, Mamestra brassicae, and the role of melanin in thermoregulation|
|Publisher:||Nature Publishing Group|
|Citation:||Goulson D (1994) Determination of larval melanization in the moth, Mamestra brassicae, and the role of melanin in thermoregulation, Heredity, 73 (5), pp. 471-479.|
|Abstract:||Variability in the colour of lepidopteran larvae has been recorded in a broad range of species, yet little is known of its evolutionary significance, or whether it has a genetic basis. I assess the role of genes and environment in determining the degree of larval melanization in the moth, Mamestra brassicae, and examine functional aspects of larval pigmentation. In particular, whether melanization is of importance in thermoregulation, and whether larvae differing in melanization exhibit concurrent differences in size, rate of development, and fecundity. In the fourth and fifth instars, larval M. brassicae exhibit a continuous range of colour from pale green to black: a classification scheme is described to quantify this variation. Heritability (h2) was measured using regression of brood means against mid-parent values for 36 broods (2339 offspring), and was estimated to be 0.237 0.07 (SD) for fourth instar larvae and 0.421 0.10 (SD) for fifth instar larvae. However, environmental factors mediated development of larval colour: larvae were darker when reared at low temperature (12°C) compared to high (24°C). Direct measurement of larval temperatures using thermocouples inserted into the alimentary canal indicated that dark larvae absorbed more radiant heat, and thus under illumination consistently maintained a higher body temperature than pale larvae. Hence dark larvae are presumed to be at a selective advantage at low ambient temperatures, and increased melanization of larvae reared at low temperatures may be adaptive. I suggest that variation within natural populations may be maintained by fluctuating weather conditions. Dark larvae were found to be smaller, but developed more quickly than light larvae so that weight at pupation, time to pupation, and fecundity (measured by the number of fertile eggs produced) did not differ according to colour. Further studies are suggested to examine the influence of larval colour on thermoregulation, growth rates and predation in the fiel|
|Rights:||The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author. You can only request a copy if you wish to use this work for your own research or private study.|
|Affiliation:||Biological and Environmental Sciences|
|Goulson_Determination_of_larval_1994.pdf||320.47 kB||Adobe PDF||Under Embargo until 31/12/2999 Request a copy|
Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependant on the depositor still being contactable at their original email address.
This item is protected by original copyright
Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
If you believe that any material held in STORRE infringes copyright, please contact email@example.com providing details and we will remove the Work from public display in STORRE and investigate your claim.