Newsletter of the Biological Survey of Canada (Terrestrial Arthropods)

Volume 19 No. 1, Spring 2000


 

Project update: Seasonal adaptations in insects

 

General information and editorial notes

News and Notes

Activities at the Entomological Societies' Meeting
Summary of the Scientific Committee Meeting
Symposium on Biodiversity
Yukon book well received

Project Update: seasonal adaptations in insects

The Quiz Page

Jumping Spiders of Canada

Selected Future Conferences

Answers to Faunal Quiz

Quips and Quotes

List of Requests for Material or Information required for Studies of the Canadian Fauna 2000

Cooperation Offered

List of Addresses

Index to Taxa

 

 

 

 

 

 

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Seasonality is a dominant feature of Canadian environments. The Survey’s long-standing project on seasonal adaptations in insects addresses various topics in conjunction with the roles of seasonal constraints in determining the fauna of the country, especially in northern regions. In northern Canada, conditions are so severe that many species cannot meet the resulting environmental challenges. Some consideration of seasonal adaptations therefore is included in various predominantly faunal publications of the Survey on Canadian, arctic, boreal, and Yukon regions.

More specific Survey studies and reviews have addressed a range of seasonal themes, such as cold hardiness and dormancy / diapause, as well as seasonal control and other aspects of life cycles more generally. These approaches have yielded several key findings. For cold hardiness, they include the importance of habitat choice as well as physiological and biochemical mechanisms of cold hardiness, and the need to integrate many elements – such as timing and energy use as well as just seasonally cold temperatures – into understanding cold hardiness. Recent work on cold hardiness focusses on the parallels between desiccation protection and cryoprotection, especially the role of trehalose; and on adaptations of species from harsh environments such as the high arctic moth Gynaephora groenlandica (cf. Arctic Insect News 10: 7-10, 1999) including a recent NSERC grant for cooperative work that includes the genetic control of some elements of the response.

A recent analysis of dehydration in dormant insects considers many features linked to both cold hardiness and dormancy. For dormancy, a major conclusion from the Survey’s project is the need to view dormancies as developmental pathways that are an alternative to direct development. In this view, life cycles comprise a series of successive developmental choices rather than the action of a simple on-off switch. Such a conclusion, and more general consideration of the diversity and evolution of insect life cycles, emphasizes the breadth of trade-offs that must be understood to evaluate any particular life cycle. Recent work in this field includes several attempts to identify key patterns in the responses and fruitful ways to study them. These discussions again reinforce the value (in contrast to piecemeal studies prevalent in the past) of studying multiple facets of adaptation simultaneously in single species, preferably those that are relatively well known taxonomically (to avoid unpleasant surprises about the identity of the material) and for which there is adequate ecological information (so that key habitats and ecological pressures are already known).

The Survey’s project continues with other reviews in progress on the themes of cold hardiness, dormancies and life cycles.

 Selected references

BSC Newsletter. 1988. Canadian perspectives: Arthropod cold-hardiness. Newsletter of the Biological Survey of Canada (Terrestrial Arthropods) 7(2): 42-44.

BSC Newsletter. 1992. Activities at the 1991 Entomological Societies meeting - Cold-hardiness symposium. Newsletter of the Biological Survey of Canada (Terrestrial Arthropods) 11(1): 11.

Danks, H.V. 1979. Characteristic modes of adaptation in the Canadian insect fauna. pp. 548-566 in H.V. Danks (Ed.), Canada and its insect fauna. Mem. ent. Soc. Can. 108. 573 pp.

Danks, H.V. 1980. Arthropods of Polar Bear Pass, Bathurst Island, Arctic Canada. Syllogeus 25. 68 pp.

Danks, H.V. 1981. Arctic Arthropods. A review of systematics and ecology with particular reference to North American fauna. Entomological Society of Canada, Ottawa. 608 pp.

Danks, H.V. 1987. Insect dormancy: an ecological perspective. Biological Survey of Canada (Terrestrial Arthropods), Ottawa. 439 pp.

Danks, H.V. 1987. Insect-plant interactions in arctic regions. Rev. Ent. Quebec. 31: 52-75.

Danks, H.V. 1990. Arctic insects: instructive diversity. pp. 444-470, Vol. II in C.R. Harington (Ed.), Canada’s missing dimension: Science and history in the Canadian arctic islands. Canadian Museum of Nature, Ottawa. 2 vols, 855 pp.

Danks, H.V. 1991. Winter habitats and ecological adaptations for winter survival. pp. 231-259 in R.E. Lee and D.L. Denlinger (Eds), Insects at Low Temperature. Chapman and Hall, New York and London. 513 pp.

Danks, H.V. 1991. Life-cycle pathways and the analysis of complex life cycles in insects. Can. Ent. 123: 23-40.

Danks, H.V. 1992.  Long life cycles in insects. Can. Ent. 124: 167-187.

Danks, H.V. 1993. [Seasonal adaptations in insects from the high arctic.] pp. 54-66 in M. Takeda and S. Tanaka (Eds.), [Seasonal adaptation and diapause in insects]. Bun-ichi-Sogo Publ., Ltd., Tokyo. 447 pp. (In Japanese).

Danks, H.V. (Ed.) 1994. Insect life-cycle polymorphism: theory, evolution and ecological consequences for seasonality and diapause control. Kluwer Academic Publishers, Dordrecht, Netherlands. Series Entomologica 52. 376 pp.

Danks, H.V. 1994. Diversity and integration of life-cycle controls in insects. pp. 5–40 in H.V. Danks (Ed.), 1994.

Danks, H.V. 1994. Insect life-cycle polymorphism: current ideas and future prospects. pp. 349–365 in H.V. Danks (Ed.), 1994.

Danks, H.V. 1996. The wider integration of studies on insect cold-hardiness. European Journal of Entomology 93: 383-403.

Danks, H.V. 1999. Life cycles in polar arthropods – flexible or programmed? European Journal of Entomology 96: 83-102.

Danks, H.V. 1999. La dormance et les cycles biologiques. Antennae 6: 5-8.

Danks, H.V. 1999. The diversity and evolution of insect life cycles. Entomological Science 2: 651-660.

Danks, H.V. 2000. Dehydration in dormant insects. Journal of Insect Physiology, in press.

Danks, H.V., J.A. Downes, D.J. Larson and G.G.E. Scudder. 1997. Insects of the Yukon: characteristics and history. pp. 963-1013 in H.V. Danks and J.A. Downes (Eds.). Insects of the Yukon. Biological Survey of Canada (Terrestrial Arthropods), Ottawa. 1034 pp.

Danks, H.V. and R.G. Foottit. 1989. Insects of the boreal zone of Canada. Can. Ent. 121: 626-677.

Danks, H.V., O. Kukal and R.A. Ring. 1994. Insect cold-hardiness: insights from the Arctic. Arctic 47: 391-404.

Ring, R.A. and H.V. Danks. 1994. Desiccation and cryoprotection: overlapping adaptations. Cryo-Letters 15: 181-190.

Ring, R.A. and H.V. Danks. 1998. The role of trehalose in cold-hardiness and desiccation. Cryo-Letters 19: 275-282. 

  

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